Mineral resources of Alaska : report on progress of investigations in 1910

Brooks, Alfred H. (Alfred Hulse) · 1911 · Historical

Mineral resources of Alaska : report on progress of investigations in 1910 by Brooks, Alfred H. (Alfred Hulse) (1911). Full text and reference in the…

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DEPARTMEST OK THE INTEBIOU UNITED STATES flEOLCXilCAL SiritVEY

QEOEUtE OTIS SMITH. DiRRnoft BULLKTIN- 480

MINERAL RESOIiRCKS OF ALASKA

EEPOKT OX OK INVESTKiATIONS IN

Alfrki) H. Axi) Otiteks

Washington

a O V B It N M E N T P H I X T 1 X ( 1 K K I C K

t.

Contents.

Page.

Administrative report, by A. H. Brooks 5

Report on progress of surveys of public lands in Alaska during 1910, by A. H.

Brooks 15

The mining industry in 1910, by A. H. Brooks. 21

Geologic features of Alaskan metalliferous lodes, by A. H. Brooks 43

fining in southeastern Alaska, by Adolph Knopf 94

The Eagle River region, by Adolph Knopf 103

The upper Susitna and Chistochina districts, by F. H. Mofl5t 112

Preliminary report on a detailed survey of part of the Matanuska coal fields,

byG. C.Martin 128

A reconnaissance of the Willow Creek gold region, by F. J. Katz 139

Placer mining in the Yukon-Tanana region, by C. E. Ellsworth and G. L.

Parker 153

Water supply of the Yukon-Tanana region, 1910, by C. E. Ellsworth and G. L.

Parker 173

Mineral resources of the Bonnifield region, by S. R. Capps 218

Gold placer mining developments in the Innoko-ldi tared region, by A. G.

Maddren 236

The Shungnak region, Kobuk Valley, by P. S. Smith and H. M. Eakin 271

The Squirrel River placers, by P. S. Smith 306

Index 32 1

Illustrations,

Page. Plate I. Map of Alaska showing known distribution of metalliferous deposits In pocket.

II. Geologic reconnaissance map of southeastern Alaska, showing relation of ore deposits to intrusive rocks 46

III. Geologic sketch map of central Alaska 48

IV. Geologic sketch map of Yukon-Tanana region 52

y. Geologic map of Mountain region, southeastern Alaska,

showing relation of copper deposits to intrusive rocks 74

VI. Geologic sketch map of Kotsina-Chitina copper belt 82

VII. Sketch map of upper Susitna and Chistochina River basins 114

VIII. Preliminary geologic map of part of the Matanuska coal field 130

IX. Structure sections in the Matanuska Valley 136

X. Sketch map of Bonnifield region 220

XI. Map of southwestern Alaska, showing location of Innoko and

Iditarod placer districts 236

XII. Geologic sketch map of Shungnak region 274

}C1II. Sketch map of southeastern part of Squirrel River basin 306

4 Illustbatioxs.

FifiLHE 1. I*riifilo section fnim nmiith fif Sheep <*reek to Sheep Ifauntain,

Juiit-aii ili.-irit t. r-hnwin Iim-uj* of aurifeiuiii minermliiatioa tt

2. tiviiiTali/iNi f-rirvM --fIiln nf Silver Queen and Glscier niinei>,

Jwiiiiiu <ii-irii fl

.-k<'iih map of UkIcp in Fairbanks district C4

4. Ihau'raiiiinatir H-('ti>>ii nf I'Xixicure in canyon of Skwentna River,

illuiraiiiii; iniiii*rali/ation in batAlt along contact off granite

r>. PiaLTaniniarir ulon Krn.*:in):Uin tunnel, Bemen Bay,

t>. .-kf'iih nf nnrihwcrst of Duuglai* Island 68

7. (iniiiii:i<- >kt'i4-h map ami ri'tinn of Ophir Creek region, Seward J'ciiiiiMila. .''howimr diitribuiion of and of mineralization ill n'latin to tin* Iimfstono-i<"liiM fontart 72

5. niau'Rimmaiir MTtinn nf 4hi.<t, Bluff rion, Seward

I'rnin'ula 73

!). riaii and ri-i-tinn of Amlrcw mine workings, Ketchikan

dir'trit-t. of tin* b'>dii*s 76

10. Skcirh ]ilan ami Hf-ti'n of at Rush dc Brown mine,

>hiwitiir ore hiNlifs ami ri.*laiioii of minonilization to contact iM'twt'cii ;;raitiMlinriti' ami con'lonieratc 77

11. H'ctimi mrir ('oitonwcNNl Bay. Iliamna region, show-

imr mimTjIi/atioii ai roinart zoiu' of limestone and diabase. ... 78

12. (ii*oli''ic .<k<'trli ma] of Niklai Cix-ek, i'opjMT River region, show-

ing n'latioii of (oppiT IihIi*.*: to Liu It zone ami to limestone-green-

Mom* S4

Sk't<'h ma J) of i1m* vicinity of tlu* Hoiianza mine, Copper River

ri7;ioii, relation of cnppcT (l4>]>o.xitj to limestone-green-

Htim' coiitaft 85

II. .'kj'tch map of wi'M iMul of Si'wanl showing

rrlalioii if till fl(])oits to intnisivo nK-k." 89

15. Hki'Nh map of ilu' virginity of VaMi'z TriM'k 117

Id. Sketch map of ]ar1 of Valdoz (ri'fk, howin;: pUuor-mining camps. 120 17. nhowinj? ndalion of the Monuhan tunnel to

Valdi'Z Croi'k 121

IK, tii'oliiric <'h map of Willow nijioii 143

Sk'lrli map of of iioriliw<'stTn Alaska, showing,' hnnitiun of

iShungnuk and Squirrtd KiviT rt'ions 272

- .

Investigation Of The Mineral-Resources

Of Alaska In 1910;>.-

By Alfred H. Brooks and others.

Administrative Report.

By Alfred H. Brooks.

Preface.

This volume is the seventh of the series issued annually by the Geological Survey, each of which summarizes for the year both the conditioBte of the mining industry and the most important results obtained by the investigations of the mineral wealth. The purpose of these reports is to furnish a convenient handbook for those interested in the mining industry of Alaska and to make available the more important economic results of the year's surveys in advance of the publication of complete reports, which usually require at least six months for office preparation by the author and then, because each must await its turn, from two or three months to a year for publication. In a region like Alaska, where developments are going on rapidly, such a delay after the completion of the field work may seriously impair the value of the publication to the prospector. On the other hand, the publication of the advance statements in these progress reports implies hasty preparation and in some cases the presentation of conclusions which may be changed by the more exhaustive office study. Therefore those interested in any particular district are urged to procure a copy of the more complete report as soon as it is issued.

The same arrangement will be maintained in this volume as in those previously issued. First will be presented papers of a general character, followed by those referring to special districts, wliich will be Aranged geographically from south to north. This' bulletin contains 15 papers by 11 authors, of which 2 deal with administrative

1 Report on progress of investigation of the mineral resources of Alaska, 1904: Bull. U. 8. Geol. Survey No. 2SB, 1905; Idem, 1905: Bull. 284. 190G; Idem. 190G: Bull. 314, 1907; Idem, 1907: Bull. 345, 19U8; Idem, 1908: BulL 379, 1909; Idem, 1909: BuU. 442, 1910.

6 Mineral Resources Of Alaska, 1910.

matters, 3 are summaries of Qome features of the mining industry, and the remainder deal mprpWifically with problems of economic

In the preparatiQi>.of-tRe summaries of the mining industries the writer, as in grew's years, has in part been dependent on information various sources, for it is impossible with the small jEofce'\available to have a representative of the Survey visit each, ©f'kd* many Alaska mining districts. These summaries could UQt'b prepared were it not for the cordial cooperation of the residents /l.\oirthe Territory, including mine operators. Federal officials, officers of banks and of transportation and commercial companies, mining engineers, and many prospectors. It would be impossible to enumerate all those who have contributed information, but special acknowledgment should be made to the following: The Director of the Mint; S. Irvine Stone, of Kodiak; Melvin Dempsey, of Dempsey; H. S. Ferris and H. P. Gallagher, of Susitna; W. M. Harrison, of Cache Creek; E. R. Stivers, of Fortymile; J. J. Hillard, of Eagle; Ralph Donaldson, of Rampart; Benjamin F. Baker and Joseph H. Eglar, of Tofty; WiUiam A. Fitzpatrick, of Chena; D. H. Boyer, Alaska Pacific Express Co., First National Bank, and Washington, Alaska & Fairbanks Banking Co., of Fairbanks; F. J. Marsh, of Caro; John A. Dexter, of Chenik; C. W. Thornton, of Solomon; and J. W. J. Reed, of Nome.

During the season of 1910, 12 parties were engaged in Alaskan surveys for varying lengths of time between April 1 and October 17. In addition to these the geologist in charge did some field work. The personnel of these parties included 12 geologists, 4 topographers, 2 engineers, and 27 packers, cooks, etc. In addition to these some gage readers were employed who gave only part of their time to the work. Four of the parties were engaged in geologic work, two in both geologic and topographic surveys, four in topographic surveys, and two in investigating water resources.

The areas covered by geologic reconnaissance surveys, on a scale of 1 : 250,000 (4 miles to the inch), amount to 8,635 square miles; by detailed geologic surveys, on a scale of 1 : 62,500 (1 mile to the inch), 32 1 square miles. Much of the time of the geologists was devoted to the investigation of special field problems in the important mining districts, the results of which can not be presented areally. Some 13,815 square miles of topographic reconnaissance surveys, on a scale of 1 : 250,000 (4 miles to the inch), and 36 square miles of detailed topographic surveys, on a scale of 1 : 62,500 (1 mile to the inch), were completed.

In 1910, 54 gaging stations were maintained in the Yukon-Tanana region for an average of 143 weeks each, furnishing data on the water resources of about 4,700 square miles. Fifteen gaging stations

Administbative Report. 7

were also maintained for 170 weeks in iSeward Peninsula, yielding data on the run-off of some 1,800 square miles.

To state the work geographical', two parties were in southeastern Alaska, three in the Copper River and Susitna basins, one in the Matanuska Valley, three in the upper Yukon basin, two in the Innoko-Iditarod region, and one in the Kobuk region.

Among the important results of the year were the completion of the detailed survey of that part of the Juneau gold belt which lies between Salmon Creek and Berners Bay and of the part of the Matanuska coal field lying west of Chickaloon River and the completion of the geologic and topographic reconnaissance mapping of the Bonnifield district, the Valdez Creek region, and the most important part of the Innoko and Iditarod region. The accumulation of data on the water resources of the Yukon-Tanana region and of Seward Peninsula is yielding results of importance to the placer-mining industry.

The following table shows the allotment, including both field and oflTice expenses, of the total appropriation of 890,000 to the districts investigated :

Allotment to Alaskan surveys ami investigations in 1910.

Southeastern Alaska $5, 100

Copper River region 27, 000

Matanuska region 9, 600

Upper Yukon basin 23, 800

Innoko-Iditarod region 14, 100

Northwestern Alaska, including Seward Peninsula 10, 400

90,000

In the following table the approximate amount of money devoted to each class of investigations and surveys is indicated. It is not possible always to give the exact figures, as in some cases the same party or even the same man has carried on two different kinds of work, but this statement will help to elucidate a later table which will summarize the complete areal surveys.

Approximate allotments to different kinds of surveys arid investigations in 1910.

Geologic reconnaissance surveys $26, 500

Detailed geologic surveys 11, 500

Special geologic investigations 2, 500

Topographic reconnaissance siu-veys 32, 000

Detailed topographic surveys 1, 600

Investigation of water resources 4, 600

Collection of statistics of mineral production 1, 100

Miscellaneous, including clerical salaries, administration, inspection, instruments, office supplies, and equipment 10, 200

90,000

8 Mineral Besources Of Alaska, 1910.

Allolmena for taUtriu andJUld txpenta, 1910.

Scientific and UirhDical salttriea $29, 330

Field expenses 51, 765

Clericftl and other office sJariea 8, 906

90,000

The following table exhibits the progress of the Alaskan investigations and the annual grant of funds since systematic surveys were begun in 1898. It should be noted that a varying amount b expended each year on special investigations, yielding resultswiiicli can not be expressed areally.

Progrtu eftwveyt in Alasia, ISSfi-HtlO."

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it 1'

w.uoo.oo

sS

SU.DDbOO W, 000.00 go, 009.00

9u!oou!oo

I'm'

e!ooo

si 000 3.O10

8,.m.

B,Iw)

8,330

8."i96'

5B

iO.

"o'.Tbo s,§ao lu.iuo

t.ioo

a

2,830

e.Aoo s.eas

"'ssii' m

'mm

0,48D 4,880

13, an

uo

18D

3U

2ca

"i4

a

'S

'.71, 189. 80

"o™

00, .s i.m

ir.BsoiM.sss

vs

m

7S

la thbi table dLITerAomewbat Trom (hosr pr [n pnri lo Ihc inlH-TlfloiUon of Ihe work and Ld ptict lo the lt

f In ailillllan lo lY ubove the Inlfmatlonal Bouadary Surrey a madt sun'tys ol parts of Alaska.

Geographic Distribution Of Investigations.

Oenesal Work.

The writer was engaged in olfice work at Washington until August 3, when he proceeded to Alaska, reaching Valdez on August 15. A day wtis spent in visiting the Cliff mine, and the journey was continued to Seward and then to Knik, two days being spent en route in studying the geology' in the vicinity of Kem Creek. From Knik

Administrative Bepobt. 9

the writer proceeded to Mr. Martin's camp, which was reached on August 23. The following two weeks were spent in studying the geology of the Matanuska coal field, and then the writer returned to Seward. A day at Knik and several days at Seward were utilized in collecting data to be used for planning subdivisional surveys in this general region. (See pp. 16-20.) Returning, the writer reached Washington on September 30.

Of the time spent in the office the geologist in charge has devoted about 30 days to the completion of the Mount McKinley report (Professional Paper 70), about 50 days to the progress report, 15 days to subdivisional surveys (see pp. 15-20), and the rest to routine miscellaneous matters.

R. H. Sargent continued the general supervision of the topographic surveys and map compilation, as in the previous year, but since July 1 his time has been largely devoted to the subdivisional surveys of Alaska public lands.

E. M. Aten continued as office assistant to the geologist in charge and supervised the office work during the writer's absence in the field. He also continued to assist in the collection of statistics of production of precious metals in Alaska.

. The office study of the problems relating to the stratigraphy of Alaskan Tertiary coal measures was continued by W. W. Atwood during such time as he could spare from his college work. As the correlating of the coal measures of different parts of the Territory depends on the determination of their fossil plants, Arthur Hollick was employed for a part of the year on a systematic study of the large amount of paleobotanic material already collected.

SOTJTHEASTEBN ALASSLAl.

Adolph Kjiopf was employed from June 3 to September 7 in completing the detailed geologic mapping and study of the mineral resources of the Eagle River region. In this time he covered an area of 125 square miles. He then devoted 11 days to studying special mining problems near Juneau, 5 days to the Sitka mining district, and 11 days to collecting data on the mining developments in other parts of southeastern Alaska. (See pp. 94-110.)

J. W. Bagley, assisted by C. E. Giffin, spent the time from May 6 to Jime 6 in detailed topographic mapping of an area of 36 square miles in the vicinity of Mendenhall River, thus completing the surveying of the Eagle River district.

C. W. Wright was employed from July 6 to September 17 in continuing the work of preparing a report on the geology and mineral resources of Kasaan Peninsula and Hetta Inlet ron. Unfortunately, he was called back to his professional work in Sardinia before he could complete his report, but he has promised an early completion.

10 Mineral Resources Of Alaska, 1910.

Copper Biveb Ani> Susitna Begion.

D. C. Witherspoon and C. E. Gillin began a topographic rec*onnaissance survey in the upper Chistochina region on July 1 and carried it westward into the Susitna basin, includuig the Valdez Ceek placer district. The party was divided into two sections and continued work until September 12, covering an area of 4,980 square miles.

F. H. Moilit, assisted by B. L. Johnson, made a geologic rei*onnaissance survey of the southern front of the Alaska Range between the Fairbanks trail and Valdez Creek. He also made a reexamination of the Clustochina placer district, which had previously been mapped by W. C. Mendenhall. The Moilit party began work July 8 and continued until September 3. A geologic reconnaissance maj) of about 1,000 square miles was completed, in addition to wliich the topographic surveys and geologic notes furnished by the Witherspoon party furnished a general knowledge of the areal distribution of the principal formations over some 2,000 square miles. A preliminary statement of Mr. Mofht's results is presented on pages 112-126.

PRINCE WILLIAM SOUND AND H:e:NAI PENINSULA.

No field work was done in the Prince William Sound and Kenai Peninsula regions other than that accomplished by the geologist in charge (p. 8). U. S. Grant has continued, so far as his collegiate duties permitted, the work of writing a on the eastern part of the Kenai Peninsula.

matanusblal valley.

G. C. Martin, assisted F. J. Katz and Theodore Cliapin, made a detailed geologic survey of that part of the Matanuska coal field lying between Moose Creek on the west and Chickaloon River on the east. An area of 196 square was surveyed during tlie period extending from June 3 to September 8. (See pp. 1 2S-1 38. ) At the close of the season Mr. Katz, assisted by Mr. Chapin, spent about a week in studying the mineral resources of the Willow Creek region. (See pp. 139-151.)

Uppeb Yukon Basin.

No geologic field work was done in the Yukon-Tanana region, but L. M. Prindle spent nine months of the year in preparing a detailed report on the region adjacent to Fairbanks and a more general report on the Fairbanks quadrangle. C. E. Ellsworth and G. L. Parker continued the study of the water resources of the Yukon- Tanana region which was begun in 1907. They began field work at Fairbanks on April 1 and then extended it into the Birch Creek district. Mr. Parker continued stream gaging in the Fairbanks

Administrative Report. 11

and Birch Creek districts until September 1, when he went to Nome (p. 12). After organizing the work in these two districts, Mr. Ellsworth went to Eagle, which he reached on June 11, and began a systematic study of the water supply of the Fortymile region. This work was continued until September 19. A summary of the results of these investigations is presented on pages 173-217 of this volume. J. W. Bagley, topographer, and S. R. Capps, geologist, carried a topographic and geologic reconnaissance survey from the upper Nenana Valley eastward to Delta River. The area surveyed includes 3,135 square miles and is bounded on the south by the crest of the Alaska Range and on the north by the lowlands of the Tanana Valley. These surveys were begun on June 26 and completed on September 13. The area surveyed includes the Bonnifield placer district and the larger part of the Nenana coal field. (See pp. 218-235.)

Innoko-Lditabod Region.

The continued interest in the placer-gold deposits of the Innoko basin, including the newly discovered Iditarod placers, led to extending the work previously done in this field. G. C. Anderson made a topographic reconnaissance survey of an area of 3,200 square miles, extending southward from Ruby Creek, on the Yukon, across the upper Irinoko Valley, and including much of the Iditarod basin. A. G. Maddren, assisted by H. E. Birkner, made a geologic reconnaissance survey of about 2,000 square miles of the most important part of the same region, besides investigating the placers of the Innoko and Iditarod districts. (See pp. 236-270.) The work was begun on June 19 and continued until September 16.

NOBTHWESTEBN ALASSLAl.

P. S. Smith and H. M. Eakin carried a geologic and topographic reconnaissance survey from the to Kobuk River. The party landed near the mouth of Hogatza River on June 22 and traveled overland to Dahl Creek, on the Kobuk. (See pp. 271-305.) A contract had been made to have suppUes delivered at this point, but an accident had prevented delivery and the party was therefore forced to abandon the original plan of extending the survey southwest to Seward Peninsula and made its way down the Kobuk by small boat. This, however, gave opportunity to pay a hasty visit to the newly discovered Squirrel River placer district (see pp. 306-319), where the field work was ended on August 21. In spite of the season's work being curtailed by loss of suppUes, an area of 2,500 square miles was covered by geologic and topographic reconnaissance surveys.

Systematic investigations of the water supply of Seward Peninsula have been carried on each year since 1906. The need of investigation

12 Mineral Besoubces Of Alaska, 1910.

in other parts of Alaska made it impossible to detail an engineer to continue this work in 1910. Through the cooperation of a number of mine operators it has been possible to keep up some gaging stations during the open season of 1910. In addition to the data thus obtained, G. L. Parker spent from September 15 to October 18 in Seward Peninsula in collecting the gage readings furnished by individuals and in making stream measurements. All these data are now being used in the preparation of a summary report on the water resources of Seward Peninsula.

Collection Of Statistics.

As in previous years, the statistics of the gold, silver, and copper production of Alaska were collected by the writer, assisted by members of the field force and by Mr. Aten. Every year a larger percentage of the operators show their interest in this work by furnishing data of production. There are, unfortunately, still a rather large number of placer-mine operators who neglect to make returns of production, though the schedules are mailed to them each year. Such action, by decreasing the accuracy of the pubUshed totals for each district, injures the mining industry. It is believed that a large part of those who fail to report their production ignore the request sent by schedule because of the rush of work during the short open mining season. There may be some, however, who dislike to reveal their gold production, even to the Geological Survey. Those operators who have hesitated to furnish the desired information for fear it might be used to their disadvantage are reminded of the fact that the Geological Survey has received confidential information from practically every mining corporation in the States for many years and has never been charged with betraying a confidence. The figures furnished are used only to make up totals of districts, and every precaution is taken to prevent their being published in any way to indicate the output of individuals or corporations unless permission has been explicitly granted in writing.

The attention of all those interested in the advancement of the mining industry of Alaska is directed to the fact that it will be greatly to the advantage of this industry if accurate figures of the gold output of each district are published. If funds were available for sending a representative into each district to collect the required information in person, complete and reliable figures could undoubtedly be had. As it is, the work is still largely done by correspondence, and the address list of operators is by no means complete. It is expected, however, that soon every operator in the Territory will report his production, so that accurate totals for each district can be published. Until this is done the figures of production can be only approximate. Fortunately, there are other though less exact sources of information.

Abminibtbative Bepobt. 13

The statement of placer-gold production as presented is, then, based in part on the returns from operators and in part on data furnished by bankers, express companies. Federal officials, and other residents of Alaska.

Publications Issued Or In Preparation.

During 1910 the Survey published five bulletins relating to Alaska. Three bulletins, one professional paper, and two maps are in press. The authors' work on two other reports, to appear as bulletins, has been completed, and illustrations for these are being prepared. The office work on eight other reports is sufficiently advanced to make it reasonably certain that they will be ready to submit for publication on or before the 1st of July, 1911. Six other reports will probably be submitted during the year 1911. The reports in press or in preparation include 14 new topographic maps, to be published on scales of 1 : 500,000, 1 : 250,000, or 1 : 62,500.

Reports Issued.

The Innoko gold-placer district, Alaska, with accounts of the central Kuskokwim

Valley and the Ruby Creek and Gold Hill placers, by A. G. Maddren. Bulletin

Mineral resources of the Nabesna-White River district, Alaska, by F. H. Moffit and

Adolph Knopf; with a section on the Quaternary, by S. R. Capps. Bulletin 417 . Geology and mineral resources of the Solomon and Casadepaga quadrangles, Seward

Peninsula, Alaska, by Philip S. Smith. Bulletin 433. Mineral resources of Alaska in 1909, by A. H. Brooks and others. Bulletin 442. ReconnaiBsance of the geology and mineral resources of Prince William Sound, Alaska,

by U. S. Grant and D. F. Iliggins. Bulletin 443.

Reports In Press.

The Mount McKinley region, Alaska, by A. H. with descriptions of the

igneous rocks and of the Bonnifield and Kantishna districte, by L. M. Prindle.

Professional Paper 70. Geolcy and mineral resources of the Bcmers Bay region, by Adolph Knopf. Bulletin

446. [Issued February 16, 1911.] Geology and mineral resources of the Nizina region, Alaska, by F. H. Moffit and

S. R. Capps. Bulletin 448. Geologic reconnaissance in southeastern Seward Peninsula and Norton Bay-Nulato

region, Alaska, by P. S. Smith and H. M. Eakin. Bulletin 449. [Issued June

17, 1911.]

Reports In Preparation.

The Yakutat Bay earthquake of September, 1899, by R. S. Tarr and Lawrence Martin.

Professional Paper 69. Geology and mineral resources of parts of the Alaska Peninsula, by W. W. Atwood;

including geologic and topographic reconnaissance maps. Bulletin 467. Geologic reconnaissance of the Iliamna region, Alaska, by G. C. Martin and F. J.

Katz, including geologic and topographic reconnaissance maps. Bulletin 485. Greology and ore deposits of Kasaan Peninsula and the Copper Mountain region, Prince

of Wales Island, by 0. W. Wright; including detailed geologic and topographic

maps.

14 Mineral Resources Of Alaska, 1910.

Geology of Glacier Bay and Lituya region, by F. E. Wright and C. W. Wright, including geologic reconnaissance maps. Geology and mineral resources of the Eagle River region, by Adolph Knopf; including

detailed geologic and topographic maps. Preliminary report on mineral deposits of Sitka region, by Adolph Knopf. The headwater region of the Gulkana and Susitna rivers, with an account of the

Chistochina and Valdez Creek placers, by F. H. Moffit, including geologic and

topographic reconnaissance maps. Geology and mineral resources of the southern part of Kenai Peninsula, by U. S.

Grant and D. F. Higgins, including geologic reconnaissance maps. The coal fields of the lower Matanuska Valley, by G. C. Martin. Geology and mineral resources of the Fairbanks district, by L. M. Prindle and F. J.

Katz; including detailed topographic and geologic maps. The Fairbanks quadrangle, by L. M. Prindle; including geologic and topographic

reconnaissance maps. The Bonnifield region of the Tanana Valley, by S. R. Capps; including geologic and

topographic reconnaissance maps. The Koyukuk-Chandalar gold region, by A. G. Maddren; including geologic and

topographic reconnaissance maps. The Iditarod-lnnoko region, by A. G. Maddren; including geologic and topographic

reconnaissance maps. Geology of the Nome and Grand Central quadrangles, by F. II. Moffit and Philip S.

Smith; including detailed geologic map. The water supply of Seward Peninsula, by F. F. Uenshaw and P. S. Smith; including

topographic reconnaissance map.

Report On Progress Of Surveys Of Public Lands

In Alaska During 1910.

By Alfred H. Brooks.

Introduction.

An item in the sundry civil act approved June 25, 1910, provided "for the survey of the lands in the United States in the District of Alaska, $100,000/' In accordance with instructions, the Director of the Geological Survey, on June 25, 1910, submitted plans for the surveys authorized by this item to the Secretary through the Commissioner of the General Land OflBce. These were approved by the Commissioner and by the Secretary on June 29. In a letter dated June 29 the Director instructed the geologist in charge of the division of Alaskan mineral resources to put the plans into execution.

Otjtijine Op Plans.

The approved plans authorized the following surveys:

1. The astronomic determination of the latitude, longitude, and azimuth in the vicinity of the initial point of the proposed surveys near Fairbanks.

2. Time permitting, the astronomic determination of latitude, longitude, and azimuth at another point near the mouth of Tanana River which might be used as a reference point for future land surveys in this district.

3. Tlie inauguration of a triangulation system in the vicinity of Fairbanks by which the accurate location of land Unes and corners could be determined and which could also be developed so as to permit extensions into other areas where subdivisional surveys are needed.

4. The extension of a base and meridian from the initial point near Fairbanks.

5. The surveying of such township exteriors as were deemed advisable.

6. Time permitting, the subdivision of these townships.

7. The making of reconnaissances in the Copper River, Seward, and Matanuska regions for the sake of obtaining information on which to plan surveys in these provinces,

16 Mineral Resources Op Alaska, 1910.

Methods Of Survey.

The surveys provided for three classes of work — astronomic determination of positions, trianulation, and linear measurement.

The astronomic work was performed by the Coast and (Geodetic Survey in accordance with its long-established standards and methods.

The triangulation, including measurement of base, was executed in accordance with the standards and methods of the Geological Survey.

The approved plans authorized the making of linear measurements either by stadia or with steel tape, depending on the physical character of the country to be surveyed. In either method the standard set for accuracy was to be maintained. In practice it was found that the lines actually run could be best measured by steel tape. There is no doubt, however, that under favorable conditions the stadia is applicable and advisable.

Tlie plans approved also provided that the township comers should be tied to triangulation points so far as practical, thus giving an entirely inde[>endent check on the line work. It is worthy of note that this is the first time that any subdivisional surveys made by the United States Government have been checked by triangulation. The United States is the only country in the world which does not use geodetic methods in making its land surveys.

Soon after reaching the field the engineers satisfied themselves that in this latitude and under existing climatic conditions the old method of controlling tlie azimuth of linear surveys by means of solar transit was not for the following reasons:

1 . Observations on Polaris tJirough the small telescopes of the transits are impracticable before tjio 10th of August.

2. The altitude of Polaris, about 65° in this latitude, increases the difficulty of acciu*ate observations.

3. The sun's path in tliis higli latitude is such that solar observations for a good part of the day arc very unreliable.

4. During tlie season of 1910, owing to climatic conditions, the sim was visible for solar observations onlv about one-fifth of the time.

Accordingly the lines were run as plain transit lines on the basis of the azimuth determination made at the astronomic station and transferred to the different lines by the triangulation system. This not only saved time but yielded results of a higher degree of accuracy than could be obtained in this latitude by the old method.

Personnel.

As provided for in tlie plans submitted, the Superintendent of the Coast and Geodetic Survey detailed the necessary engineers to make the latitude, longitude, and azimuth determinations at Fairbanka and at the mouth of the Tanaua*

Triangulation party: 1 engineer in charge. 1 axman. 1 packer. l*cook. 1 recorder.

Surveys Of Public Lands During 1910. 17

R. H. Sargent, topographer, was put in charge of the field parties at Fairbanks. C. L. Nelson, W. N. Vance, and S. G. Lunde, topographers, were detailed to assist Mr. Sargent. In addition to these four engineers, who were detailed from the permanent staff of the Geological Survey, four chainmen and one recorder accompanied the party from Seattle. At Fairbanks 21 other men were engaged as rodmen, amen, packers, cooks, etc.

The personnel of the two line parties and the triangulation party were as follows :

Line parties:

1 engineer in charge. 4 chainmen.

2 flagmen.

3 amen. 1 cook. 1 teamster.

Mr. Salient was directed, after inaugurating the work at Fairbanks, to proceed by trail to Valdez and make the necessary investigations along tliis route to procure information needed for planning future work in tliis field.

Mr. Brooks undertook similar investigations in the northeastern part of Kenai Peninsula and in the Matanuska region.

Distribution Op Time Of Field Parties.

To attain eflBcient and economic administration, the Fairbanks parties should have gone inland over the winter trail; and had this been done, some field work might have been begun by the 1st of May. As a matter of fact, the money was not available until July 1 , and therefore the parties could not leave for the field until that date. Mr. Sargent, Mr. Nelson, and Mr. Lunde, with four chainmen and one recorder, sailed from Seattle on July 5 and arrived at Fairbanks, by way of the Wliite Pass route, on July 22. The field parties were at once organized and the measurement of a base line was begun the following day. Mr. Vance, whose departure from Seattle had been unavoidably delayed, reached Fairbanks on August 8. On August 9 line work was begun by two parties and continued until about October 7. Meanwhile the third party had been engaged in triangulation. Topograpliic surveys along the surveyed lines was begun about October 10 and continued until about October 20, when stormy weather necessitated the disbanding of the field parties.

Mr. Sargent organized the work at Fairbanks and continued with the parties until September 15. Ho then spent 14 days in investigating conditions which would affect future surveys in tlie region traversed by the Valdez-Fairbanks trail.

Mr. Brooks was detained in Wasliington by office duties until August 3. He sailed from Seattle on August 8 and arrived at Seward 8319— BuU. 480—11 2

18 Mineral. Be80Urce8 Op Alaska, 1910.

on August 18. Continuing his journey, he arrived at Knik on August 20. From August 21 until September 9 he spent in the Knik Arm and Matanuska region. Returning, he sailed from Seward for Seattle on September 17.

The combined time of Mr. Vance and Mr. Lunde, chiefs of the line parties, from the dates of their leaving the office to their return, was 281 days, a detailed account of which follows:

Days.

Travel to field and return 113

Measuring triangulation base line and couHtructing astronomic

stations 14

Line work 85

Topographic surveying 21

Field computations and office work 5

Outfitting 3

Stormy weather 14i

Moving camp 12i

Days observed as Sundays 13

Upon Mr. Sargent's departure, Mr. Nelson was left in charge of the field work and thereafter devoted the larger part of his time to administrative duties. He was employed 43 days on field work in connection with the triangulation, 48 days on supervision and computation, 60 days in traveling, and 10 days in outfitting.

Results.

Astronomic determinations. — An astronomic determination of latitude, longitude, and azimuth was made at a station near Fairbanks by the Coast and Geodetic Survey. A similar determination was made at Tanana, a settlement on the west bank of tlie Yukon, at the mouth of Tanana River. This was in accordance with the approved plans and an agreement made between the Secretary of tlie Interior and the Secretary of Commerce and Labor under date of July 5, 1910. The Superintendent of the Coast and Geodetic Survey transmitted the results of the final computations of these observations on February 6, 1911.

Triangulatian. — A base line was measured and a system of triangulation inaugurated, tlie geodetic position of which was based on the astronomic observations. Tliis triangulation not only checked the line surveys but can also be extended into adjacent parts of the Tanana Valley to provide points from which land surveys of important areas may be executed in the future. By this means the projecticm of long standard parallels and guide meridians tlirough areas of no commercial importance will be avoided.

The primary triangulation stations are marked by bronze tablets, furnished by the General Land Office, firmly set in concrete or solid

Subvets Op Pubuo Lands Dubino 1910. 19

rock. Preparatory to the future expansion of the triangulation system six signals have been constructed on prominent hills in the Tanana Vallev.

SumTnary of triangulation.

Base line measured feet. . 13, 876. 674

Primary stations occupied 12

Secondary stations occupied 15

Points intersected 3

Signals constructed 6

Line work. — The Une work consisted chiefly of extending base and meridian lines and the survey of township exteriors. Some section Unes and a few meanders were also run. The geodetic position of the initial point was determined by triangulation. It seemed desirable not to attempt the sectionizing of the townships until the matter of the rights of the homesteaders had been settled.

Summary of line surveys.

Miles.

Principal meridians 23. 7

Base line 18

Township exteriors 43. 7

Section lines 11. 8

Meanders 11.7

It was impossible to ship iron posts to Fairbanks in time to make them available for the season's work. Wooden posts were therefore set, properly inscribed and witnessed in accordance with the regulations of the General Land Office.

The number of corners set was as follows:

Initial point 1

Township comers 7

Standard town?hip comers 3

Closing township comers 3

Section comers. . .' 76

Quarter comers 88

Meander comers 8

Witness comers 8

Cost Of Surveys.

The expenditures for public-land surveys in Alaska to and including May 15, 1911, were as follows:

Geological Survey $32. 59 1 . 02

Coast and Geodetic Survey 2,013.06

The estimated liabiUties are $528.19. The total cost of these surveys is therefore $35,132.27.

Office Work.

Mr. Nelson was furloughed on January 12, thus leaving Messrs. Sargent, Vance, and Lunde to work upon the notes and plats.

20 Mineral. Resources Of Alaska, 1910.

The following data were transmitted to the Commissioner of the General Land Office on May 15, 1911: Notes and plats of land lines; results of astronomic observations; notes and results of triangulation base measurements, all corrections being computed ; notes and results of the triangulation with least-square adjustment applied.

Recommendation For Continuation Op Surveys.

If the policy established last year of surveying the arable lands, especially those which are now being taken up as homesteads, is to be continued, there are tliree general provinces in wliich work should be done — the Tanana Valley, the Cook Inlet region, and the Copper River valley.

In the Tanana Valley the subdivision of townships whose exteriors have already been surveyed should be completed and the surveys should be extended by means of the triangulation system into adjacent areas wliere homesteads luive been taken up.

In the Copper River region the positions of the base and meridian lines already surveyed should be astronomically determined, so that the township sui'veys in tliis field can be accurately tied to other Alaskan surveys. To obtain an accurate datum for elevations, a line of primary levels should be nm from Cordova to Fairbanks. A triangulation should bo carried up the Cliitina Valley, so as to provide a tie point for subdivisional sui'veys, whicli will soon be needed in this field because of the demands of settlers now being attracted by the railway that is under construction. Plans should be made to subdivide the arable lands in the Chitina Valley.

In the Cook Inlet region it seems desirable to subdivide the flats and floors of tributary valleys adjacent to Rasurrecticm Bay. These survey should bo tied to triangulation of the Coast and Geodetic Survey. It is also desirable to begin townsliip surveys at Knik and at Seward, <'.covering the arable lands of the vicinity. These surveys should also be tied to the Coast and Oeodetic Survey triangulation.

If the coal fields are to be subdivided, work should be begun in the Bering River, Matanuska, and Nenana fields. The surveys in the Bering River field should be tied by triangulation to points of known position on the coast. The Matanuska surveys should be tied by triangulation to Coast Survey points on Knik Arm. The Nenana field can readily be reached by extending the Fairbanks triangulation southward.

It is furthermore recommended that authority be obtained, by lislation if necessary, to permit the boundaries of bona fide homesteads to stand as recorded. All the members of the Geological Survey who are conversant with the conditions are agreed that if the rights to lands as recorded by homesteaders are not recognized grave injustice may be done.

The Mining Industry In 1910.

By Alfred H. Brooks.

Introduction.

The gold and copper lode-mining industry of Alaska made considerable progress in 1910, not so much in output as in the amount of dead work accomplished. On the other hand, there was a falling oflf in the production of the placer mines and an absolute stagnation in all enterprises depending on the opening of the coal fields.

As in previous years, the lack of cheap fuel is the one great hindrance to the advancement of the mining industry in Alaska. So long as the Pacific seaboard of Alaska and the adjacent portions of the inland region have to depend on expensive coal brought from British Columbia, Japan, and Washington, so long will the industries of the Territory suffer. With coal at $8 to $20 a ton along the Pacific seaboard of Alaska, even mines located at tidewater are at great economic disadvantage. Under such conditions only the richest and largest ore bodies can be mined at a profit. Moreover, railway construction will be active only when there is an assured tonnage from the coal fields and when cheap fuel for operating is available.

The inadequacy of the mineral-land laws wliich to placer claims continues to hamper the mining industry by discouraging the bona fide miner and prospector. This condition, while ever present, is emphasized when a new district is discovered and a few men, often mere speculators and not miners, can preempt large tracts of land and hold tliem for a year and sometimes nearly two years without doing any development work.

In spite of the decreased gold production and the handicap because of the delay in opening the coal fields, considerable advance was made in the mining industry. Copper mining was prosperous and much development work was done on the copper deposits. More has been accomplished than in any previous year in the development of auriferous lodes. Much work was also done toward installing large mining plants for working low-grade placer deposits. The decrease

MtKJS£tAL &£gOURC£S OlP ALASKA, 1610.

In the value of the gold production is entirely chargeable to the falling off in the output from the placer mines of Fairbanks, Seward Peninsula, and some of the smaller placer districts. Except in these camps and the coal fields, the output from all the mining districts increased.

The value of the total mineral production in 1910 is estimated at $16,925,178; in 1909 it was $21,141,019. In the following table the sources of this wealth, as well as a comparison with the previous year, are presented. The statistics for gold and silver output are not yet completed and may be subject to change, but the figures for the other mineral products are presented with more confidence as to their accuracy.

It sliould be noted that the apparent increase in silver production in 1910 as compared 1909 is due largely to the fact that in the past tlie silver content of the placer gold has been estimated too low. This is due to the fact that the placer-gold producers make no returns of the silver content of their gold output. The placer silver, which occurs as an impurity in the gold, can be arrived at only by a computation based on the purity of the gold. The accumulation of data on the composition of the placer gold from the several districts during the last six years has made it possible to compute the silver percentage more accurately and has shown that in the statistics |)ublished in the past the estimate for placer silver is too low.

In the table the outputs of marble, tin, gqsum, etc., are combined because a separate listing migjit reveal the production of individual properties.

Mineral production of Alaska, 1909-10.

OoW ounces. ,

Silver do...

Copper pounds. .

Coal. short tons. .

Marble, psum. tin, mineral water, and lead

Quantity.

147,9,'iO.OU 4,124,700.00 2,800.00

Value.

1910 a

Increase ( f ) or decrease (— ).

Quantity. Value.

120,411,710

70,U;i4

103,858

781.83J1.7')

109,418.00

1,400.00

$10,102,000

538.09.') 13,000

119,398

Quantity

—205. 5S0. 01 + 110.984.00 — 1.400.00

Value.

—$4,249,710 +- 14.551 4- 2.484

+ 1,300

15. Wo

21,141,019

10.925,178

4.215.841

a Preliminary est linats.

Note.— In the above table copper is valued at 13 cents a poimd for 1909 and 12.7 cents for 1910; silver at 52 cents an ounce for 1909 and 54 cents for 1910.

Mining began in Alaska in 1S80, but for many years no very accurate records of mineral output wore kept. Since 1905, however, fairly reliable statistics of mineral production are available. Tliese data are summarized in the following table, both by years and by substances:

THE MINING INDUSTBY IN 1910. Valtu of total mineral produetioa of Abuia, 1880-1910.

Hjyeaa.

Uy tubdiances.

Usd-Imo U

is

S86,S7S

Im

IMS IMft 1907— - IMS 190B

.. I.oo7.a66

S,M,Bb3

.. bmTsu .. 9.m.m

.. IB,iM,l .. 33,3TS,0ae .. ai.MT.QSS .. 30.142,37!

::-i6;ia,<i78

Oold

.. 178,;St.171

Iw,31I,3T0

Im, 311,370

Transportation.

The nondevelopment of the coal fields has put the railways at a double disadvantage. In the first place, those of the Pacific slope ron are paying $11 to $12 a ton for coal used in operating, when high-grade coal Hhould cost them only from $2.50 to $3.50. Moreover, the imported coal is of an inferior quality compared with the native fuels. In the second place, the coal tonnage needed to help support the railways is nonexistent. In spite of these handicaps, the backers of some of the railway projects have shown commendable enterprise in either continuing construction work or preparing for it.

The most important event of the year in the development of transportation routes was the extension of the River & Northwestern Eailway to about mile 150. As tliis report goes to press telraphic dispatches announce that this railway has been completed to Kennicott, a distance of 195 miles from the coast at Cordova. This affords an outlet for the copper ores of the Kotsina- Chitina district and renders the Nizina placer district readily accessible. It also both shortens the winter sled route to Fairbanks and does away with the nece.'wity of crossing the high coastal barrier. It will also decrease the cost of transportation to the Valdez Creek and Chbtochina placer districts and render the copper belt of upper Nabesna and White rivers more accessible. With the changing of the trail from Chitina to Fairbanks into a wagon road, which is now being accomplished by the Alaska Road Commission as fast as funds available permit, an overland summer route to the Tanana camps will be opened. Take it all in all, this is the most important advance made in the history of Alaska trans])ortation since steamboat service was established on the Yukon about half a century ago.

The Alaska Nortliern Railway did no new construction work of the coal-land situation, but it maintained communication over ita 71 miles of track which connects Seward, the coastal terminal, with the head of Tumagain Arm. By the use of small launches a route

24 Mineral. Resources Of Alaska, 1910.

of communication with Knik and points on Susitna River was thus estabUshed, wliich is competitive with the older route from Cook Inlet. Some location surveys were also made beyond the end of the road. This railway, when completed, will lead to the development of the Matanuska coal field and the Willow Creek lode district, as well as other mining districts of the Susitna basin, besides making accessible extensive areas of arable land.

Most of the other railway projects appear to have lain dormant awaiting the settlement of the coal-land question. The completed railways, such as the Wliite Pass, Tanana Valley, and Seward Peninsula, were operated but need no special mention. At the close of 1910 the aggregate length of all Alaska railways was about 420 miles, compared with 371.4 miles at the close of 1909. Tliis mileage is distributed among nine different railways, from 5 to 196 miles in length.

Among the important work accomplished by the Alaska Road Commission, in addition to the continuation of work on the Valdez- Fairbanks wagon road, already referred to, was the preparation for the estabUshment of a winter trail from the inland terminus of the Alaska Northern Railway to the Innoko-Iditarod region. This serve the placer miners of the Susitna basin, the Kuskokwim, and the Innoko-Iditarod and will shorten the winter mail route from the Pacific seaboard to Nome by about 300 miles. The commission also built or improved many other roads and trails in different parts of the Territory.

Metal Mining. Introdxjction.

In 19l0 about one-quarter of the gold production came from lode mines and three-quarters from ].laccrs. It is a significant fact that in 1909 only one-fifth of the gold came from lode mines. The ratio of lode production to placer production has varied considerably during the 30 years that mining has been carried on. In the first two or tliree years the gold output was almost all from placers. With the opening of the lode mines of the Juneau belt the lode production became larger than the placer, the ratio in 1894 being about 2 to 1. Five years later, when the Nome placers were developed, the ratio of lode to placer output decreased to about 1 to 3. After this the percentage of lode production gradually decreased until 1910, when it began to rise. A further increase in the ratio of gold lode to placer output is to be expected. In the following table, which is based on the preliminary estimates, the metal production has been distributed as to source :

The Mining Indobtbt In 1910.

urea of gold, rilver, and copper in Ahtia, 1910.

Gold.

8,1

C0„„.

V-u..

Pounds.

Value.

199,686.26

sm.xd.to

U,\2t.(m 12,000:000

tii!n8

116,983

241, 889

781,836.76

100,118

538,686

In the following table the production of gold, silver, and copper is given by years. The fluctuations in the gold output are chaiseable to the discovery of bonanza placer deposits, which at different times in the past have yielded laie (niantities of gold. This form of mining, while still continuing, will probably in the future contribute a decreasing percentage of the gold production, and as a result there will be lees marked Suctuations in the annual output.

Produrtion o/gold, tilcer, and copper in Alaita, 1380-1910.

Oolii.

sn

.r.

rapper.

Yau.

Qimitlly

QtaDlily (flue

i-alSe.

tJuantUy (pounds).

imi

M;,wa

si.m

30! 882 43,638

Ii2,M2

iH

271). B97 M6,U3a 336. 3M

m.-m

75Iu01

i.flOfi.rHO uw.ow

130 oon

10,320 2,320

m'.xo

'Ie

92,oon

is

i4T!a6u

..1,14..

e!o7i

7,920

7,000 a,STo

90! 087 m!s76 46! 494

Is

M!i8a

a,B33

3Ik

m

2,3b 3! 481

Km. Kxa

8,883

is

tin

lit m

4:8ti5;23n

4. IM. 706 4. 241. Hi)

I78,7W

2,130,199

1.2i.B78

33.;M,108

n.KH.Tin

In the following table the total gold production is distributed according to districts, so far as the information at hand will |>ermit. The error in distribution is believed to be less V't ictv.,

Mineral Besoubces Of Alaska, 1910.

and it is hoped in future statements to eliminate it altogether. The production from the Pacmc coast belt is for the most part from the lode mines of southeastern Alaska but includes also a small placer output, as well as the production from a lode mine on Unga Island. The gold credited to the Cook Inlet and Copper River region is, aside from the output of some small quartz mines in the Susitna basin and on Kenai Peninsula, all from placers and includes the yield of the Nizina, Cliistochina, Sunrise, Yentna, and Valdez Creek districts.

The gold output of Seward Peninsula and the Yukon basin is nearly all from placers, though there was a small output from the lode prospects of the Fairbanks districts, at least one of which can be classed as a mine.

Value of gold production of Alaska, unih approximale distribtUionf 1S80-1910.

Year.

1880 S20,000

1 881 40, 000

1882 150.000

1883 300.000

18W 200.000

1Sr5

1886 4ir.. OCX)

18.S7 (>J5. c<:o

1888 8ir).0H)

1889 MiO. WK)

1890 712.

1891 800. Oth)

1892 970. (Xk)

1893 h:. (xm

1894 882. 0()

1895 1 . 5<)J. 500

1896 1.041. ("00

1897 1 . 799. .'(X)

1898 1. S:)2. (Xx)

1899 2, 152. (Xh)

1900 2. 000

1901 2. 072. 000

1902 2. (W

1903 2. S43.

1904 ' 3. 105. Soo

lOa*) ' 3. l.-JO. 000

1906 I 3. 454. 704

1907 2. S91 . 743

190S 3. 448, 318

190) ; 4. 264. 710

1910 1 4, 2.37. 000

coa.st

belt.

Copper River and Cook Inlet

region.

150. Iso. (Xx) 375. (Xx) 375.

(Kx) .332, (Xx) 401,500

Yukon basin.

52.261.971 4.358.500

$1,000

.So. 000

100. (Kx>

110. (Xx)

200. (Xx)

400. (Xx)

Soo. (Xx)

450. (Xx)

400, (Xx)

(V50.

5.50. 000

1, (Xx). 000

1.. 300. 000

10, 7.')0. (Xx)

9,

10. 32.3.

all, 580.000

a 8. 04.5, 000

Seward

and northwestern Alaska.

Total.

$15,000 75. OCX) 2. SOO. 000 4.750.000 4.1.30.700 4, .561. 800 4.405.(i00 4.164,600 4.800.000 7.500.<XX) 7.000.000 5, 4.302 000 3.5.30.000

57.214.700

$20,000

900,000

900,000

1,080.000

1,033.000

1,282,000

2,328.500

2,861.000

2,439,500

2,517,000

5.602,000

8,166,000

6.932,700

8.283.400

8, 683, 600

9, 160, 400

15.630,000

22,036,704

19,349.743

19.292.818

20,411,716

16.162,000

178,797,171

a Includes a small from the Kaskokwim.

Lodes.

Development And Production.

The total gold production from the auriferous lode mines of Alaska which have been productive since 1882 is estimated to he 2,346,635 fine ounces, valued at $48,602,775. These mines have also produced 1,001,241 fine ounces of silver, with a commercial value of $611,808.

This refers, of course, only to the .Maskan parts of the Yukon basin and does not include the production of the Klondike and other Canadian camps.

TUt MtNlNG INDUSTRY IN 1910. 27

The total copper production up to the close of 1910 was 33,775,108 pounds, valued at $5,338,709. Tin mining began in the York region in 1902, since which time it has been carried on spasmodically. The value of the total tin product, which has come chiefly from the placers, up to the close of 1910 is $139,639. There has also been some recovery of lead from ores valuable chiefly for other metals.

While the output of the auriferous lodes in 1910 was about the same as that of 1909, marked advances were made in installing mining plants and in prospecting. As a result it is most probable that the lode-gold output in 1911 will be greater than that of 1910 and that the production will increase very much in the next two or three years.

Alaska's auriferous lodes are estimated to have produced during the year 199,595 fine ounces of gold, valued at $4,126,000, as compared with an output of 199,181 fine ounces, valued at $4,117,440, in 1909. The output of the Juneau district was somewhat less than in the previous year, but this is only a temporary setback, for the large amount of development accomplished assures a larger output in 1911. The increased output must be credited to the Sitka, Port Valdez, and other smaller districts. Noteworthy advances in prospecting auriferous lodes were made in the Prince WilUam Sound region, Kenai Peninsula, at Willow Creek, and in the Fairbanks district.

There were 14 productive gold-lode mines in operation in Alaska in 1910, two more than in 1909. Work was also done on more than 50 gold prospects, a few of which produced some gold as an incident to the development work. Of the producing mines six were in the Juneau district.

It is estimated that these mines had an output of 1,400,000 tons of ore, as compared with 1,496,361 tons, the total output for 1909. The decrease in tonnage with an increase in value of gold output indicates the relatively larger percentage of the total made by mines exploiting high-grade ores. In 1909 the average value of gold-silver contents for all the ores mined wixs $2.72; the average in 1910 is estimated to have been $2.85.

There were six productive copper mines in 1910, as compared with seven in 1909. In addition to these there were several properties which produced some copper incidental to development work. The certainty that the Kennicott-Bonanza mine will be shipping ore in 1911 assures a very large increase in the copper production. Further more, other Alaska copper njines are making preparations to increase their output, and several properties which have not yet been productive will probably begin shipping some ore in 1911. All of this assures a rapid expansion of Alaska's copper-mining industry.

The total copper production in 1910 was 4,241,689 pounds, valued at $538,695, compared with 4,124,705 pounds, valued at $536,211, in 1909. About $36,000 worth of gold and $14,202 worth of silver was

28 MINERAL BESOITBOES OF ALA&KAj 1910.

recovered from the copper ores. It is estimated that in 1910 about 39,000 short tons of copper ore was hoisted, as compared with 34,669 tons in 1909. The average copper content of the ore was about 5.4 per cent and the gold-silver values about $1.29 to the ton.

SUMMARY OF LODE MINING BY LOCALITIES. PACIFIC COAST REOIOir.

Except for a small production at Fairbanks, all of the auriferouslode gold came from mines situated on the Pacific seaboard or in the drainage basins tributary to it. Lode mining, especially that of the Treadwell group of mines, in the Juneau district, continues to overshadow all other enterprises of this kind. Mr. Knopf on pages 94-1 1 1 summarizes the mining developments of the year in southeastern Alaska.

KotsinaChitina district, — The most important event of the year in the Kotsina-Chitina copper district was the extension of the Copper River & Northwestern Railway, already referred to on page 23. As this report goes to press (April, 1911) a telegraphic dispatch from Cordova announces tliat the first train load of copper ore has been shipped to the coast from the Kennicott-Bonanza mine. This is one of the most important events in the history of Alaska's mining industry, as it assures the opening of a region which promises to become an important producer of copper.

The Kennicott-Bonanza is now fully equipped to ship ore, of which a large quantity of extraordinary riclmess has been blocked out. Tlie deepest workings are from 150 to 160 feet below the surface. During 1910 the most important development was the construction of ore bins and a concentrator at the railwav terminal, which is connected with tlie mine by an aerial tram 15,000 feet in length.

The assurance of a railway has led to much prospecting of other claims in the Kotsina-Chitina district, detailed information in regard to which is, however, lacking at this writing. It is reported that the development work done on the Mother Lode group of claims, which he on the McCarty Creek side of the Bonanza divide, has opened some very promising ore bodies. The work accomplished in the Kotsina region, at the west end of the copper belt, is also reported to have developed some good ore bodies. Up to the present time the aggregate amount of rock work accomplished, outside of the Kennicott-Bonanza, has been very little, but now that quick and comparatively cheap transportation is assured, more systematic development will undoubtedly be undertaken.

Lower Copper River basin. — The Bremner and Tiekel regions of the lower Copper River basin have long been known to carr}' auriferous gravels, some of which have been mined in a small way. In 1910

The Mining Industry In 1910. 29

some auriferous quartz veins were found in this district. So far as known, their geologic occurrence is similar to that of the veins of Port Valdez. Interest in gold-bearing lodes was revived in the McKinley Lake region in 1910 by some new discoveries. These discoveries are a few miles north of Algonik, a station on the Copper River & Northwestern Railway about 22 miles from Cordova.

Prince WiUiam Sound, — The most important event of the year in the Prince WiUiam Sound region was the development of an auriferous lode mining district on Port Valdez. Though some of the gravels of this region have long been known to be auriferous, little search was made for lode deposits until 1909 and no commercial ore bodies were developed until 1910. The most important prospects thus far discovered lie in an area bounded on the east by Valdez Glaciers, on the south by Port Valdez, on the west by Shoup Bay and Shoup Glacier, and on the north by a less well defined line lying 2 to 5 xniles from tidewater. Some prospects have also been located on the south side of Port Valdez. Within this area more than 200 lode claims have been staked, most of them during 1910. As during all other periods of mining excitement, only a small fraction of these claims can be expected to contain commercial ore bodies. The facts that one mine has been opened, that several other prospects have been sufficiently developed to give promise of carrying commercial ores, and that auriferous mineralization is widely distributed augur well for the future of the district.

The mine, the only property which has been put on a productive basis, is located near the eastern entrance to Shoup Bay, about 8 miles west of the town of Valdez. The claim was staked in 1909 (?), development work began in July, 1909, and a 3-stamp mill, said to have a capacity of 30 tons a day, was installed in April, 1910. As, however, up to the time of the writer's visit (August, 1910) only one concentrating table was in use, the mill had been run only two shifts (16 hours) each day. The mine was operated until December, when it was temporarily closed, but work was resumed in Januaiy,

The following notes are based on a hasty visit :

The country rock at the mine appears to be chiefly dark sihceous slate, in places graphitic and usually blocky. At the beach the strike is about east and west and the dip 20° to 30° N. The slate carries mica and is in places heavily charged with finely divided pyrite, which occurs in veinlets cutting the fohation and is also disseminated especially along the cleavage planes. There has been movement later than the pyrite, as is shown by slickensided surfaces about parallel to the cleavage.

The vein cuts across the foliation of phyllites with a strike of about N. 30° to 45° W., averaging about N. 35° W. It dips southwest at

80 Mineral Resources Of Alaska, 1910.

an angle of about 50° to 70° but has some rolls in it. The footwall is smooth and along it there is from half an inch to 3 inches of gouge which carries values. There seems to have been no movement along the hanging wall, but it is well defined. The vein varies in width from, say, an inch, where quartz may be entirely lacking, to 34 inches. The managers report that small swellings occur where the vein widens out to 3 and 4J feet. The vein matter is in places entirely lacking, but the fissure is everywhere well defined. In one place in the upper tunnel a roll was encoimtered where a bulge in the footwall gave a reverse dip to the vein. On the whole, the strike of the vein is fairly uniform in direction, though the workings show minor swings of 5° to 10°. At the upper prospect tumiel, about 150 to 200 feet above the beach, what to be the same vein has a thickness of about a foot. So far as determined by the exposures, the vein is definitely recognizable for about 300 to 400 feet, but the managers stated that it has been traced by float tliroughout the length of the claim, and it is reported that the same vein has been found on the north side of the ridge, a distance of probably 3,000 feet from the mine.

The typical vein filling is a blue quartz carrying considerable finely disseminated pyrite and also apparently minute quantities of arsenopyrite and galena, but no detailed study of ore has been made. Visible free gold is found, especially in the upper workings, where there has been considerable oxidation. Free gold occurs, however, in the fresh, unaltered vein material, where it is clearly not the product of alteration. In ])laces the ore shows a rough banding, and this type is re])orted to carry the liighest values. Some of the vein material is crushed and some shows a suggestion of brecciation and recementation.

Much of the ore is very rich, and the average recovery of free gold is currently reported to $50 to the ton. The manager reports no noteworthy change in values between the upper and the lower workings. The concentrates are said to run about 7 per cent and to have a value of about $100 a ton in gold.

Oxidation of vein matter is marked on the upper level and was observed on the lower level to a distance of about 100 feet from the entrance of the adit. Beyond 100 feet on the lower adit there was no evidence of oxidation. The superintendent, Ray Millard, stated to the writer that there was no diminution in free-gold values at depth. At the same time the richest s])ecimens of free gold seem to have been taken from the upper part of the mine. Values of $1.50 to $6 are reported in the hanging-wall rock, in wliich many quartz stringers were observed extending a distance of a foot or more from the vein. In the upper adit the vein matter is absent from the last 50 feet, but the fissure is traceable. It is in this part of the mine that the roU occurs.

The Miking Industry In 1010. 81

There are two adit tunnels (which are connected by raises) 64 feet apart and one intermediate drift. Plans are made for sinking on the vein in the lower tunnel. There is ako a prospecting tunnel which is 150 to 200 feet above the beach. The lower adit is about 200 feet long. According to the manager, a winze has been sunk to a depth of 50 feet below the lower adit since the writer's visit. At this depth the ore body seems to maintain itself and there are reported to be no notable changes in gold tenor.

No exact information is available regarding the many other properties which have been more or less prospected. Along the shores of Port Valdez, near the CUflf mine, are a number of veins, some of which have been developed by adit tunnels, but these were not examined by the writer. At the Imperial an adit has been driven along the vein for a hundred feet, and since the writer's visit an air compressor has been installed. A 3-stamp mill has also been erected near this point and probably on this property. In the fall of 1910 prospecting was being pushed on six or seven properties located on Mineral Creek. Of these the Williams-Gentzler property, about miles from the beach, is said to be one of the most promising. Here a well-defined 18-inch quartz vein carrying high gold values is reported. A wagon road has been completed from Valdez to Mineral Creek and up that stream about 4 miles.

There has also been considerable gold-lode prospecting in other parts of Prince William Sound. Encouraging results are reported from Jackpot Bay and from McClure Bay, both on the west side of the sound.

In the aggregate there was considerable work done on the copper lodes of Prince WilUam Soimd, tliough the low price of copper rather discouraged any except the strong companies from putting their properties on a shipping basis. Work was continued on the properties on Landlocked and Galena bays, though so far as known they made no shipments.

The Glacial Island Copper Co. is said to have opened a body of high-grade chalcopyrite ore by a tunnel 170 feet in length. The vein is said to be 4 feet wide and to be exposed 150 feet above the tunnel. A small bunker has been built and the managers report that some shipments will be made in 1911.

At the Beatson-Bonanza mine, on Latouche Island, ore bunkers having a capacity of 1,500 tons were built and a small water-power plant installed. A diamond drill is being used for prospecting. Ore shipments have continued throughout the year. A compressor plant with air drills has been installed on the property of the Seattle Alaska Copper Co. near Big Bay. The managers report that a 10- stamp mill and concentrating table are to be installed to concentrate tb Ipwr-grade ores. At EUamar a horseshoe-shaped coffer-

32 Mineral. Resources Of Alaska, 1910.

dam 400 feet in length and 20 feet above low tide is being completed. A steam pumping plant has been installed and shipments of ore were made in 1910.

Kenui Peninsula, — There was great activity in quartz prospecting on Kenai Peninsula in 1910, but this district was not studied by the Geological Survey. The following notes are gleaned from numerous sources. Of the many properties which were developed to some extent, those of Watson & Snow, now incorporated under the name Wanowski Gold Mining Co., near Moose Pass, showed the greatest results. On this property several hundred feet of undergroimd work has been accomplished, work having been done on one large quartz vein and another small one, which are parallel. The larger vein is well defined, having been traced for about a mile. Plans have been formulated for erecting a stamp mill in 1911.

On False Creek the California- Alaska Mining Co. continued work on a gold-bearing quartz prospect, where an air compressor has been erected. Work was also continued on the Stevenson property, in the same neighborhood. Auriferous quartz veins have been staked at many other places in the Sunrise placer district, but these have been for the most part little developed, except for the annual assessment work. What appears to be a promising auriferous quartz vein was found north of Turnagain Arm, at the head of Crows Creek. This vein is reported to be 2 to feet in width, of which 12 to 14 inches carries very high gold values. It is said to have been traced for several hundred feet. The specimens from this lode seen by the writer sliowed free gold and iron and arsenopyrite, with a gangue of well-developed interlocking crstals of quartz.

It appears from the information at hand that the quartz veins of Kenai Peninsula are similar in their geologic relations to those of Prmce William Sound. There is, however, more than one type of vein filling. One of the lodes in the Moose Pass district appears to be a mineralized dike and hence of a diiTerent type from the other deposits wliich have been opened. At the Cliff mine, in the Port Valdez district, the values are largely in free gold, wliile in the Kenai Peninsula veins more of the gold is combined with the Further stud} of these deposits will have to be made before more definite comparisons can be made.

Willow CreeTc, — The lode-mining developments of the Willow Creek region, north of Cook Inlet, are described by Mr. Katz on pages 139-150. These occur along the marginal contact of the great mass of granite which forms the Talkeetna Mountains. Prospectors report the occurrence of metal-bearing lodes in other parts of tlus contact zone, but Uttle is known about them and they are practically undeveloped. Such lodes are said to occur on the upper part of Granite Creek and on Little Willow Creek. On Iron Creek, a tributary of the

The Mining Industry In 1910. 33

Susitna, a lode has been found which carries chalcopyrite and pyrite,

with copper and gold values. This is reported to occur at the contact

of slate and greenstone, not far from the outer margin of the granite

mass.

Southwestern Alaska. — There are but few mining developments in

southwestern Alaska. Prospecting continued on the copper deposits

of the Iliamna region and some steps were taken to open an auriferous

lode on Popof Island. About 15 men were employed at the Apollo

mine, chiefly in development work, but sDme ore was taken out.

Some prospecting of auriferous lodes was also done on Kodiak, Dry,

and Afognak islands.

YirKOir BAsnr.

Although many lode claims have been staked in the Yukon basin, there was little actual prospecting in 1910 and no developments of importance except in the Fairbanks and Chandalar districts. The completion of a 10-stamp customs mill with full equipment at Chena in November, 1910, has stimulated auriferous-lode development. Most of the actual lode-gold production came from the smaller mill at Fairbanks, which was operated at intervals during the year. One arrastre was also operated a part of the summer season. At this writing complete returns are not available from all the lode-mining operations, but it is estimated that probably about 200 tons was milled, yielding about $20,000 in gold, besides the concentrates and some values in silver. Detailed notes in regard to all the properties are lacking. The following data are based in part on information collected by G. L. Parker, incidental to his investigations of the water supply of the Fairbanks district.

The most important developments were on the Free Gold mine of Rhodes & Hall, located near the head of Cleary Creek. A part of this property was worked under lease and a part by the owners. The main adit tunnel, which follows the ledge, is reported at the close of the year to have been driven over 630 feet, and a shaft has been sunk about 50 feet, together with a 90-foot crosscut. In this distance the ledge has been lost once or twice through pinching or faulting but has been picked up again. The ledge varies from a few inches up to 4 feet in width and has been traced on the surface for a distance of about 1,000 feet. The greatest depth of the workings below the outcrop of the lode is about 250 feet, and to this depth there is apparently no change in the character of the or.e.

An adit tunnel has been driven for about 300 feet on the property of the Tanana Quartz & Hydraulic Co., whose ledge (so far as known about 10 inches wide) parallels that of the Free Gold and lies close to it. On the "Carlisle fraction," which is also close at hand, a shaft has been sunk about 50 feet and some crosscuts have been driven. 98319°— Bull. 480—11 3

34 Mineral. Resources Of Alaska, 191.0.

Some rich ore was milled from this property, which was chiefly picked up on the surface.

Work has been continued by the Tolovana Mining Co. on its claims, where an 85-foot adit tunnel was driven, and some rich ore was mined and milled at Fairbanks. No data are at hand regarding the thickness of the ledge. This company is preparing to erect a stamp mill. Work has been continued on the Jupiter-Mars property, in the same neighborhood, where a 70-foot adit tunnel and 50-foot crosscut have been completed. Some work was also done on another group of claims on Willow Creek by Hershberger, Beall & Phipps, in the course of which some rich ore was taken out. No data are at hand regarding the thickness of the veins.

No work was done on the property of the Rex Mining Co. (Butler & Petree) on Chatham Creek, because of litigation. The total development to date includes a 160-foot incHned shaft with several prospecting levels. The vein is reported to be 4 to 8 feet in . The property of the Pioneer Co. has been leased and some prospecting was done. On the Soo claim (W. L. Spalding) a 125-foot adit tunnel has been driven and a shaft sunk to a depth of 30 feet. The vein is about 15 inches wide. Some ore milled from this property gave good returns. On the adjacent Waterbury claim a 55-foot shaft has been sunk to develop a 3-foot vein, which yields good values in gold. The ore taken from this property in the course of development was sent to the mill and a 200-foot crosscut was driven. Some rich ore was taken out of a claim on Wolf Creek by Ilorton & Solomon.

Some open cuts were made on a lode located on the divide between Wolf and Fairbanks crocks, which was discovered in 1909. This property is owned by Lawrence McCarty and Frank Lawson. Some rich ore was taken out and milled at Fairbanks. The thickness of the lode had not determined at the time of Mr. Parker's visit in August. In July and August five ledges were discovered on Fairbanks Creek. These seem to follow two systems of fissuring, one paralleling the creek and one about at right angles to this direction. They carry gold, galena, and stibnite. On the Excelsior claim a 7-foot vein is reported, according to the mining press, carrying $10 to $20 in gold and $15 to $30 in silver to the ton. Another vein is chiefly galena, with reported gold values of $5. Some ore was sliipped to Fairbanks from thase properties. The development work seems to have consisted chiefly of open cuts.

Two lodes about 300 feet apart hava been located Louis Friederich on the divide between Vault and Dome creeks. The westerly one has a granite-dike hanging wall and varies, so far as the small amount of surface work admits of determination, from 20 inches to 3 J feet in width. The easterly vein, wliich has been traced for about 800 feet, is from 3 J to 8 feet wide. It has been crosscut by an adit tunnel.

The Mining Industby In 1910. 35

Both veins cany gold values and several tons of ore have been milled. These veins contain considerable stibnite. Since Mr. Parkers visit these prospects have been further developed and others have been opened in the vicinity.

Among other prospects reported is a 3-foot vein called the Hidden Treasure, near the head of Little Eldorado Creek, developed by a 140-foot tunnel and carrying high gold values, and another in the same vicinity on which a 38-foot shaft has been sunk and which is said to be 5 feet wide. Some ore has been milled from these properties.

Some developments were made on the claims of Whitman & Murray at the junction of Skoogy and Twin creeks. Here there are two shafts, 40 to 50 feet deep, and about 400 feet of drifts and crosscuts. An arrastre was built in 1910, with which considerable ore was milled.

The above notes indicate that considerable advance was made in lode mining during the year. Most of the veins opened are small and carry high values. The developments on the Free Gold property indicate that some of the veins, at least, have a persistence which is encouraging. There is good reason to think that the geologic conditions are the same throughout that part of the Fairbanks district where lodes. have been found. All this, together with the presence of the rich gold placers, favors the beUef that workable lode deposits will be developed.

The development of auriferous quartz veins continued in the Chandalar district in 1910. Conditions of transportation were somewhat improved in this district by the completion of miles of trail from Beaver, on the Yukon, to Old Caro. In spite of thfe immense cost of transportation, a small 3-stamp mill was erected on the Gold King claims, owned by T. S. Haynes and E. W. Griffin, on Big Creek. This mill was erected with only a very insecure foundation, because of the high cost of timber, the nearest being 18 mUes distant. Some ore was put through this mill. The Alaska-Chandalar Mining Co. continued development work on its property on Squaw Creek, on which the lode is reported to be from to 8 feet wide and to carry high gold values. A 4-stamp mill has been delivered at Beaver, on the Yukon, for this company and will be sledded in during the winter of 1911-12. The men who are developing this remote district in the face of such serious obstacles, including difficulty of transportation and lack of timber and fuel, merit the highest ])raise and support.

Gold Placebs. Introduction.

The value of the placer-gold production of Alaska for 1910 is estimated at $12,000,000, as compared with $16,212,000 in 1909. The difference between these two amounts is almost exactly the

36 Mineral Resources Of Alaska, 1910.

sum of the decreased production of the Seward Peninsula and Fairbanks placers in 1910 as compared with 1909. This, however, does not tell the whole story, for in 1910 the output of the Fortymile, Rampart, and Koyukuk was less than in the previous years, but this loss was more than made up by the increased output of the Innoko-Iditarod region, whose production was more than double that of 1909. There were also small increases in the output of the placer camps of the Pacific slope as compared with previous years.

Among the most encouraging features of the year's placer mining are the large increase in the gold production of the Innoko-Iditarod region, the discovery of a new auriferous district in the Squirrel River basin of northwestern Alaska (see pp. 306-319), and the continuation of activity in the installation of dredges in Seward Peninsula. On the other hand, the delay in installing plants to exploit the extensive deposits of auriferous gravels in the Fairbanks district, whose gold values are too low to permit profitable exploitation by present mining methods, has not been encouraging. A large annual production has been maintained in the Fairbanks district up to the present time by the output from bonanza placer deposits, but deposits of this character are being rapidly depleted, and unless steps are taken to mine the gravels of lower grade, the output of the camp must continue to decline. Some advance, however, was made in the Fairbanks district, where a small dredge was built and preparations were made to install several large dredges in 1911.

In the following table the approximate yardage of the total bulk of gravels mined in Alaska during the last tliree years is presented, together with the value of the gold recovered per cubic yard. While these estimates are little more tliau scientific guesses, they are certainly near enough to tlie truth to indicate tlie order of magnitude to which the true figures belong. The estimated quantity of gravel mined is intended to include only tliat whicli is passed through the sluice boxes. Obviously, in open-cut mining any overburden which may be removed by shoveling, mechanical means, or ground sluicing will not be included in tliese totals.

Estimate of total amount of gravel sluiced in Alaska placer mines and value per cubic

yard of gold recovered, 190S-t91().

Total

(juantity

of gravel

(cubic

5'ards).

3..V)(i.00()

a.so().(.HH)

Value of

gold recovered por cubic

yard.

$4.45

These figures clearly indicate tlie iniproveiuent in mining methods which each year permits the exploitation of gravels of lower gold

The Mining Industry In 1910. 37

tenor than in the preceding year. If figures for the earUer years of placer-mining operations were available, the decrease in average gold content would be still more striking. For example, it has been estimated that the average gold content of the gravels mined on Seward Peninsula during the nine years ending in 1906 was about $5.95 a cubic yard, while gravels mined on the peninsula in 1908-1910 yielded an average of $2.85.

There is probably no better evidence of the future of the Alaska placer-mining industry than the above figures. Every reduction in cost of mining means the making available for profitable exploitation of more auriferous gravels. These gold values in the gravels mined are still more striking when compared with the average gold content of the gravels mined in the States. According to Waldemar Lindgren, the average gold recovery from all the placer mines in the States for the year 1909 was about 12 cents a cubic yard.

Summary Of Placer Mining By Localities.

PACIFIC COAST REOIOir.

For the purposes of this discussion the Pacific coast region will be made to include not only the seaboard but all the drainage basins tributary to it, including the Copper and Susitna. The placers of this province are estimated to have had in 1910 an output valued at $425,000, as compared with $330,000 in 1909. This increase is to be credited to the small districts of the region, of which the Yentna is the largest producer.

Sauiheastem Alaska, — little placer gold was mined during 1910 on Gold Creek, near Juneau, but the only important mining ventures in this part of Alaska are those of the Porcupine district, lying about 40 miles from tidewater, on Lynn Canal. The largest operations in this field were those of the Porcupine Gold Mining Co., which operated its hydrauUc plant for a good part of the season. A highline flume was completed and a bedrock drain was extended 2,000 feet in 1910. The Cahoon Creek Placer Mining Co., in the same district, accomplished much dead work, including the building of flumes. Its plant was completed in time to do considerable hydraulicking. In addition to these, there were some smaller operations in the district.

Beach mining. — Beach mining was continued at a number of localities scattered along the Pacific seaboard from Lituya Bay to Unga Island. A large part of the gold recovered in this way comes from the Yakataga beach placers. In the past the relatively small bulk of auriferous gravels contained in the beaches has discouraged aU but individual operators, who, for the most part, use the rocker. During 1910, however, steps were taken to organize a company to mine some of these beach placers on a larger scale.

1 Collier, A. J., and othera, Oold placers of parts of Seward Peninsula: Bull. U. 3- Oeol. Survey No. 328 1908, p. 136.

38 Mineral Resources Of Alaska, 1910.

Copper River region. — The jJacers of the Cliistochma district are cleicribed by Mr. Moffit on pages 1 1 2-137. Two hydraulic plants were operated in the Nizina district, besides a number of smaller plants. The output, wliich can not be published because it might serve to indicate the production of individual operators, was nearly twice as large as that of 1909. With the completion of the Copper River & Northwestern Railway this district will become readily accessible and an increased gold production is to be expected.

Sunrise district, — The placer-mining industry of the Sunrise district, including the northern part of Kenai Peninsula, had a prosperous season. This is shown not so much in the actual gold production, which is still small, as in the fact that initial steps were taken on several of the creeks to undertake mining on a large scale. These enterprises include plans for installing dredges and also for systematically exploiting groups of creek or bench claims by hydraulic methods. It is well known that there are extensive deposits of auriferous gravels whose values are too low to permit profitable exploitation by open-cut and manual methods.

During 1910 there were some half a dozen hydraulic plants, large and small, in operation in this district. One of the largest of these is on Crow Creek, where the operations of the year consisted largely in removing the heavy overburden, which covers the gold-bearing gravels, by hydraulic methods. In addition to the hydraulic mines, 15 or 20 smaller operators made some gold output.

Susltna basin. — There are in tlie Susitna basin tliree productive placer districts — Willow Creek, described by Mr. Katz on pages 150- 152 ; Valdez Creek, described by Mr. Moflit on pages 1 1 0-124; and the Yentna district. The Yentna had the most profitable season in its history. Here placer gold has been found in three distinct areas in a belt some 20 miles long, which embraces tlie foothills of the Alaska Range. Tlie most southwesterly of these includes the placers which have been found on Nakoclma River, near the mouth of Kellar Creek, and on Eagle and Independence creeks, which join Yentna River. Here only a small amount of mining has been done so far. A second gold-bearing area includes the placers of some of tlie tributaries of Lake Creek, which have been mined only on a small scale. The third and up to the present time the most important gold-bearing area in this district is that drained by Cache and Peters creeks. Tlie Cache Creek Mming Co. completed the installation of a hydraulic plant in 1910 and did considerable mining. Another company carried on large operations on Nugget Creek. The success of the.se larger has encouraged the vestigation of other properties with a view to introducing improved methods. It is estimated that about 200 men were engaged in Tnining and prospecting in the entire district.

THE MINING INDUSTRY IN 1910. 3d

Mxjlchatna Reoioit.

Mulchatna River heads in an unsurveyed area northwest of Lake Clark and flows into Bristol Bay. Gold has long been known to occur in its drainage basin, and some promising prospects are reported to have been discovered in 1910. The region is rather difficult of access, involving either a canoe trip from Cook Inlet via Iliamna and Clark lakes, with numerous portages, or a long upstream boat trip from Bristol Bay. In 1910 a steamboat was built at Bristol Bay for use on the Mulchatna. There are said to have been between 25 and 50 prospectors in this district in 1910.

YTTKON BASnr.

The value of the placer production of the Yukon basin, including the Innoko-Iditarod region, in 1910 is estimated at $8,020,000, as compared with $11,580,000 in 1909. This falling off is due largely to the decreased production of the Fairbanks district, the value of whose output was $6,100,000 in 1910 and $9,650,000 in 1909. The mining industry of the placer camps of the Yukon-Tanana region, including Fairbanks,' is described by Messrs. Ellsworth and Parker on pages 153-172 of this volume. Mr. Maddren describes the Innoko- Iditarod region on pages 236-270. It will therefore only be necessary here to refer to the remaining districts, which include those of the lower Yukon, the Chandalar, and the Koyiikuk.

Mining continued in 1910 in a small way in the Gold Hill district, which is near the mouth of the Tanana. Nothing of importance was accomplished, except preparations for mining on a larger scale than had hitherto been attempted. In the Chandalar district only three placer claims were worked in 1910. Interest centered on lode prospecting, which is referred to on page 35. Accurate figures of the gold output of the Koyukuk in 1910 are lacking at this writing, but it certainly was much less than that of 1909. This was due to the fact that the output of 1909 was far above the normal, because of the output of one or two rich spots on Nolan Creek, which were quickly mined out. According to current reports, some rich gravels were found during the year on Sheep Creek. Of perhaps greater significance is the reported occurrence of gold placers on Old Man Creek, a southerly tributary of the middle Koyukuk. It is estimated that about 300 men were engaged in mining and prospecting on the Koyukuk in 1910.

KxrsKOKwnc reoioit.

The influx of population to the Innoko-Iditarod region has led to considerable prospecting in the adjacent parts of the Kuskokwim

1 This does not include gold to the amount of over half a million dollars from other districts which passed thnnigh the town of Fairbanks. >LfOde mtauDg is described on pp. 33-36.

40 Mineral Resources Of Alaska, 1910.

basin. A trading post and settlement named Georgetown has been established on the Kuskokwim, about 325 miles above the Lelenaw anchorage, the highest point on the river reached by ocean-going vessels of any considerable size, and about 450 miles from Goodnews Bay, the nearest good harbor on Kuskokwim Bay. Georgetown affords a supply point for the Kuskokwim, and as a result there has been considerable prospecting in this general region.

The streams joining the Kuskokwim from the north near Georgetown head in the Innoko-Iditarod region and are known to carry auriferous gravels, though these have not yet been productive. (See pp. 267-269.) Some gold has also been found on the Holiknuk, a tributarv of the Chulitna, which flows into the Kuskokwim from the south 1 5 or 20 miles below Georgetown. Some placer mining was done in 1910 on Bear Creek, in the basin of Toluksak River, tributary to the Kuskokwim from the east about 20 miles above Bethel. The extent of these operations is not now known. In 1900 the discovery of placer gold in the Goodnews Bay region attracted a number of prospectors, but interest soon flagged and prospecting was abandoned. This region has again attracted prospectors, and it is reported that in 1910 some claims made a gold output. All these discoveries lie in what would be the southwesterlv extension of the Innoko-Iditarod region, and this fact alone would appear to justify further prospecting.

Northwestern

The region here termed northwestern Ahuska includes the Kobuk region, where a little placer mining was earned on in 1910 (see pp. 271-319); the Norton Buy region, where there was little or no productive mining; and Seward Peninsula, which is, in spite of its decreased output, still second only to Fairbanks in the value of its annual gold output.

The value of the gold production of Seward Peninsula in 1910 is estimated to be $3,500,000, as compared with $4,2()(),000 in 1909. In spite of tlie decreased output the mining industry, in view of the large amount of dead work accom})lished, can said to luive had a prosperous year. Ten new dredges were installed, of which nine were operated for a part of the season, in addition to seven dredges in previous years, which were also operated. About 81,400,000 worth of gold was mined during the winter season, and about 81 ,000,000 of this in the region immediately- trihutarv to Nome. Of tlie total output, some $2,200,000 is to be credited to tlie Nome precinct, including the Solomon River region. The Fairhaven ])precinct proba])Iy made an output worth half a million dollars, and the Council somewhat less. The rest of the gold is to be credited to the placer mines of the Kougarok and Port Clarence precincts.

The Mining Industry In 1910. 41

As already stated dredging was the important feature of the year's mining industry. Three dredges were installed in the region tributary to Nome, making five in all for tliis district, of which four were operated. Four dredges were operated in the Solomon basin, of which two were built in 1910. Two new dredges and three old ones were operated in the Coimcil region, and one new one in the Casadepaga basin.

Details regarding the operations of all these dredges are not available at tliis writing. It appears, however, that the 16 dredges, including the nine new ones, some of which were only completed in time for a brief test, were operated from 10 to 130 days, each averaging 58 days. The daily capacity of these dredges varies from 1,000 to 5,000 cubic yards, and they are equipped with a total of about 2,500 horsepower. The buckets vary in capacity from to 9 cubic feet, though all but five of the dredges have buckets of cubic feet or less. Two are driven by electric power, generated at one plant; seven are equipped with steam power, of which four use coal, two crude oil, and one wood. The other dredges are equipped with gasoline engines. It is estimated that the 16 dredges operated handled between 1,200,000 and 1,500,000 cubic yards of gravel, and had they all been able to operate to their full capacity they should have handled at least twice as great a yardage. It is a significant fact that the estimated bulk of gravel handled by all other forms of placer mining on the peninsula in the year 1910 is rougldy estimated to have totaled 600,000 to 800,000 cubic yards. Complete returns are not yet available regarding the gold output of the dredges, but it is estimated to have a value of about $800,000. It seems probable that the average working season should be 110 to 130 days instead of 90, as has been the ctise in the past. If this is true, the dredge production can be largely increased even without any additional macliines. Plans have already been formulated for the building of three or four dredges in 1911. If this is accomplished and the existing plants all prove efficient, it is not impossible that the output of the dredges alone in Seward Peninsula may soon reach $2,000,000. There is hope, therefore, that the gold output of the peninsula in 1910 may be the minimum for some time to come. The profits on dredging could be increased if power were furnished from one or two central stations. A further reduction in costs would be made by centralizing thd management and by building dredges of the same type with interchangeable parts.

There is no question that there is a large amount of gravel suitable for dredging on Seward Peninsula and that this form of mining is likely to increase very much. It is unfortunate that the legitimate and well-managed projects often have diflicidty in procuring the necessary capital because of a number of conspicuous failures. A

42 Mineral Resources Of Alaska, 1910.

certain class of promoters apparently believe that it is unnecessary to determine the of gold values, the tliickness of the gravels, and the distribution of ground ice before installing a dredge. Tliis point of view is probably sometimes forced on the local managers by the nonresident stockholders, who are so desirous of quick returns that they are willing to do the prospecting after the dredge is constructed. There is probably no phase of placer mining which requires such careful study of conditions and prospecting of gravel by competent engineers as does that of dredging.

While dredging was the most important industry of the peninsula during 1910, other phases of mining were not neglected. The Pioneer Co. purchased the Miocene ditch and used the water on several properties in the Nome region. Hydraulic plants were also operated on Bangor and Boulder creeks. The season's operations in the Kougarok precinct were especially successful because there was more water available than in any previous season for several years. The Taylor Creek Ditch Co., the largest operator in this district, was engaged in hydraulicking some bench gravels on Kougarok River. The Fairhaven Ditch Co. also had a successful season in the northeastern part of the peninsula.

COAL AND Olli.

Practically notliiiig was done in tlie coal fields except a few patent surveys. Most of the small mines wliich have in the past furnished lignitic coal for local use were in 1910 closed until the matter of granting patents shoidd be finally decided. On the other hand, some new drilling was done in the Katalla oil field. Some oil properties were leased and preparations were made to render the field productive.

Building Material, Etc.

Work continued on the only developed jxypsum deposit in Alaska, located on the east side of Chichagof Island, in the Sitka district. The large marble quarry located at Shakun, at the north end of Prince of Wales Island, continued shipments throughout the year. Some small shipments of garnets were made from the Wrangell district, in southeastern Alaska, in 1910. An investigation was made of the sulphur deposits of Makusjiin Volcano, on Unalaska Island, at the east end of the Aleutian chain, to determine the feasibility of mining them.

Geologic Features Of Alaskan Metalliferous

Lodes.

By Alfred H. Brooks.

Introduction.

Thirteen years of systematic investigation of the mineral resources of Alaska by the Geological Survey has yielded a large amount of information relating to the geology of the mineral deposits. Tliis has been used for the most part only in the descriptions and discussions of the economic geology of the individual districts about which reports have been published. Heretofore relatively Uttle attention has been paid to the relation of the mineral deposits of different parts of the Territory to one another or to other broader problems of economic geology. Practically the only exception is the geology of the coal fields, which has been briefly summarized.* Therefore anyone desiring information about the areal distribution and geologic occurrence of the metalUferous deposits must seek it in nearly two score publications.'

It is proposed to summarize briefly in tliis paper the salient geologic features of the metalliferous deposits of Alaska, using the results obtained by the many geologists who have worked in this field. As the facts and their interpretation are taken largely from published reports, it will be evident that tliis article can lay no claim to being an original contribution to the geology of the ore deposits. It is hoped that the matter presented will be useful, not only to those who are developing the metafile wealth of the Territory, but also to those who may desire a convenient outline of the more purely scientific results which have been achieved.

Alaska is rich in metafile wealth. Its lode and placer mines up to the close of 1910 have produced about 8,411,467 fine ounces of gold, valued at $178,789,171; 2,130,199 fine ounces of sUver, valued at $1,286,678; 33,795,108 pounds of copper, valued at $5,338,709; and about $100,000 worth of tin. The rapid advance of the mining

1 Brooks, A. H., The ooal rosouioes of Alaska: Twenty-second Ann. Rept. U. S. Geol. Survey, pt. 3, 1902, pp. 515-571. Martin, O. C, The Alaska coal fields: Bull. U. 8. Oeol. Survey No. 314, 1907, pp.40-46 Brooks, A. H., Alaska coal and its utilization: Bull. U. S. Geol. Survey No. 442, 1910, pp. 47-100.

s jSee list of publications at end of this volume.

Statistics of mineral production are presented in detail on pp. 24-28.

44 Mineral Resources Of Alaska, 1910.

industry, which had its beginning in 1880, is hidicated by the fact that over 80 per cent of the gold, almost 75 per cent of the silver, and all of the copper and tin have been produced during the last decade.

The lode production, which is the more important to the subject of this paper, includes all the copper, 2,346,635 fine ounces of gold, valued at $48,662,775, and 1,001,241 fine ounces of silver, valued at $611,608. Of this amount, the copper, 1,544,916 fine ounces of gold (value $31,845,549), and 452,190 fine ounces of silver (value $262,630) have been produced in the last 10 years. Most of the tin is from placers, but there has been a small output from lodes.

The above statistics of the output of precious metals serve only to indicate the advancement in productive mining. Of more importance to the future of the industry is the large amount of work accomplished during the last few years in prospecting and developing lode deposits. This is true not only of long-established lode-mining camps on the Pacific seaboard but also of many inland districts. These developments are constantly adding new facts bearing on the occurrence of metalliferous lodes, and hence a paper like the present one can be regarded only in the nature of a })rogress report, which should be succeeded by others after more exhaustive studies of the several districts have been made.

Geographic And Geologic Distribution Of

Metalliferous Lodes.

Introduction.

The distribution of the metalliferous lodes in Alaska is indicated on the accompanying map (PI. I, in ])ocket), on which the localities of metal deposits are indicated by symbols. It would undoubtedly add much value to this paper if the distribution of the metals could have been shown on a geologic ma]), but such a map was not ])nu*tical in this report, intended for early publication, because of the time needed both to compile the geologic data and to a map in colors. The larger features of the areal geolog}' of some of the more important parts of the Territory are represented on Plates II, III, and IV, which will be supplemented by brief verbal descriptions of the geology of the entire province.

The general map (PI. I) strikingly illustrates the ver\' wide distribution of gold in the Temtory. It will be shown that the gold is so widespread because the conditions for its deposition in the bedrock existed over large areas during Mesozoic tiine, rather than because there are many tj'pes of auriferous deposits or because they were formed during many epochs of geologic history'. (\)])])er, too, occurs in several widely separated districts, but there is less uniformity in the form of its occurrence than in that of the gold deposits.

Geologic Features Of Metallifebous Lodes. 45

The copper deposits are probably also chiefly of Mesozoic age. The tin deposits are practically all limited to one district and to one general epoch of formation.

The marked parallehsm of the larger bedrock structures which prevails throughout much of Alaska has had a wide influence on the areal distribution of many of the stratigraphic subdivisions and hence on the mineral deposits associated with them. These structures parallel the Pacific seaboard of Alaska, trending northwestward to about the one hundred and forty-ninth meridian, thence swinging to the west and southwest. As the position of the dominant mountain ranges and systems has been determined by these structures, their axes have the same trends.

The structures above noted have determined to a large extent the areal distribution of the bedrock formations, especially of those older than Upper Cretaceous. As a result of these tectonic lines, many of the geologic subdivisions occur in belts which parallel the Pacific seaboard. As it is impossible to present here a complete summary of the geology of Alaska, its larger features can probably best be elucidated by describing briefly the successive zones of rocks, similar in general lithology or age, which form the larger stratigraphic units, together with the metal deposits associated with them. These formations or zones will be described, so far as possible, in their geographic sequence from south to north. The order of treatment will have to be modified to a certain extent and some of the local geology will be presented by provinces, defined by drainage basins.

Pacific Coast Beqion.

Four large stratigrapliic units have been recognized in southeastern Alaska (see PI. II). (1) A series of Paleozoic sediments locally interbedded with greenstones, including terranes varying in age from Silurian to Carboniferous and in places highly metamorphosed. The recent investigations of Knopf in the Juneau district show that locally, at least, Mesozoic sediments are closely infolded with some of those Paleozoic rocks and that some of these are highly metamorphosed. (2) A series of Mesozoic sediments (Lower Cretaceous or Jurassic) made up largely of clastic material. (3) The great batholiths of the Coast Range, comprising intrusive rocks varying in composition from granite to diorite and later than Middle Jurassic in age. Intrusive rocks of this age and composition are also widely distributed in isolated stocks or dikes. (4) Some small areas of Tertiary (Eocene) sediments and lavas.* In general, all these rock groups can be said to occur in a series of belts which are parallel to the northwest-southeast trend of the coast line. On the east the province is bounded by a broad bolt of granitic intrusive rocks,

2 Tbere are alao some rodent lavas, which will not here be oonsidered.

46 Mineral Besoubces Of Alaska, 1910.

forming the Coast Range. Adjacent to these intrusive rocks on the west is a series of deformed Paleozoic and Mesozoic sediments. In most places a belt of metamorphosed sediments lies inmiediately adjacent to the granites of the Coast Range. A less altered series of Mesozoic or Paleozoic rocks lies next to the west. These have been locally metamorphosed by intrusive rocks lithologically similar to those of the Coast Range. The Mesozoic rocks occur in several broken belts within the areas of Paleozoic formations. One of the largest known of these belts skirts the westernmost islands of the Alexander Arcliipelago in the vicinity of Sitka.

The best-developed and largest known auriferous ore bodies of the Territory occur in a belt of Mesozoic and Paleozoic sediments (see PI. II) cUdrting the mainland of southeastern Alaska and usually separated from the granitic batholiths of the Coast Range by a zone of crystalline schists a mile or more in width. Within this general zone of mineralization is included the Juneau gold belt, from which most of the lode gold of Alaska has been produced. This is a well-defined belt of mineralization from Snettisham on the south to Bemers Bay on the north; but some gold has been found in both the northern and <)outhem extensions of tliis belt.

In addition to the deposits occurring in this zone, auriferous quartz veins have also been found in or near the marginal zones of some of the outlying intnisive masses occurring in different parts of the Alexander Arcliipelago. Noteworthy examples of these auriferous lodes are those found in the slates and graywackes, probably of Mesozoic age, of the Sitka region. These rocks do not seem to have been metaniorpliosed by granitic intrusions, which are, however, not far distant. In southeastern Alaska auriferous deposits are also found within the intrusive masses themselves.

The Ketclukan district contains some important copper deposits. Of these, the best-known type is that which occurs in the contact zones of Paleozoic limestones and intrusive rocks, but there are also other types.

An extension' of the strike lines of the formations of southeastern Alaska will carry them into the unexplored heart of the St. Elias Range. At Yakutat Bay two groups of rocks have been recognized. Tlie eastern group, wliich probably forms the bedrock of the high ranges, is made up of crystalUne and semicrystalline altered setUments, probably chiefly Paleozoic, with many intrusive rocks. The western, called the Yakutat group, consists of very highly contorted sediments, with some greenstones and other rocks, which have been provisionally referred to the Mesozoic. Little is known of the metalliferous resources of this district; but the fact that the glacial gravels derived from the St. EUas Range are locally more or less- auriferous makes it probable tliat some gold-bearing quartz veins occur in the mountains.

46 Minebal Besources Of Alaska, 1910.

forming the Coast Range. Adjacent to these intrusive rocks on the west is a series of deformed Paleozoic and Mesozoic sediments. In most places a belt of metamorphosed sediments lies immediately adjacent to the granites of the Coast Range. A less altered series of Mesozoic or Paleozoic rocks lies next to the west. These have been locally metamorphosed by intrusive rocks lithologically similar to those of the Coast Range. The Mesozoic rocks occur in several broken belts within the areas of Paleozoic formations. One of the largest known of these belts skirts the westernmost islands of the Alexander Arcliipelago in the vicinity of Sitka.

The best-developed and largest known auriferous ore bodies of the Territory occur in a belt of Mesozoic and Paleozoic sediments (see PL II) skirting, the mainland of southeastern Alaska and usually separ rated from the granitic bathoUths of the Coast Range by a zone of crystalline schists a mile or more in width. Within tliis general zone of mineralization is included the Juneau gold belt, from wliich most of the lode gold of Alaska has been produced. This is a well-defined belt of mineralization from Snettisham on the south to Borners Bay on the north; but some gold has been found in both the northern and southern extensions of tliis belt.

In addition to the deposits occurring in this zone, auriferous quartz veins have also been found in or near the marginal zones of some of the outlying intrusive masses occurring in different parts of the Alexander Archipelago. Noteworthy examples of these auriferous lodes are those found in the slates and graywackes, probably of Mesozoic age, of tlie Sitka region. These rocks do not seem to have been metamorphosed by granitic intrusions, which are, however, not far distant. In southeastern Alaska auriferous deposits are also found within the intrusive masses themselves.

The Ketcliikan district contains some important copper deposits. Of tliese, the best-known type is that wliich occurs in the contact zones of Paleozoic lijuestones and intrusive rocks, but there are also other types.

An extension of the strike Unes of the formations of southeastern Alaska will carry them into the unexplored heart of the St. Elias Range. At Yakutat Bay two groups of rocks have been recognized. The eastern group, wliich probably forms the bedrock of the high ranges, is made up of crystalUne and semicrystalline altered sediments, probably chielly Paleozoic, with many intrusive rocks. The western, called the Yakutat group, consists of very liighly contorted sediments, with some greenstones and other rocks, wliich have been provisionally referred to the Mesozoic. Little is known of tlie metalUferous resources of this district; but the fact that the glacial gravels derived from tlio St. Elias Range are locally more or less auriferous makes it probable that some gold-bearing quartz veins occur in the mountains.

D i If I a llllilir

pillilli

Geologic Features Of Metalliferous Lodes. 47

On tracing the coast line westward, metamorphic rocks of unknown age are found at Controller Bay, but are not known to carry any metalliferous deposits. These rocks are unconformably overlain by a closely folded sequence of Tertiary age bearing bituminous and antliracite coal.

Still fartlier west, on Prince William Sound, there is an older (probably Paleozoic) series of more or less altered sediments (Valdez group) overlain by a series of sediments and ancient lavas (Orca group), wluch are probably of Mesozoic age. Both series are closely folded and are locally cut by granitic intrusive rocks. The Chugach Mountains, which form the coastal barrier north of Controller Bay and Prince William Sound, so far as known, are made up of closely folded sediments, probably belonging to tlie same two groups of formations, and these are locally auriferous. In the western part of Prince WilUam Sound the bedrock formations swing to the soutliwest, and tlie same groups of metamorphic sediments occur in the eastern part of Kenai Peninsula. These are succeeded near Kachemak Bay, on the southwestern part of tlie peninsula, by Mesozoic beds. Most of the western half of Kenai Peninsula is covered by little-disturbed Tertiary Ugnilic coal-bearing rocks and by Quaternary gravels. The geology of Kodiak Island is Uttle known, but it is probable that metamorphic sediments of the same age as those of Kenai Peninsula form tlie dominating country rock, with small scattered areas of Tertiary lignite-bearing sediments.

On Prince William Sound cupriferous deposits have been found in association with the greenstones and sediments of the Orca group. Deposits of similar types occur near Resurrection Bay, an indentation of the northeastern part of Kenai Peninsula, and are reported from Kodiak Island. Auriferous quartz veins have been found at a number of places on Prince William Sound, occurring in slates and graywackes of both the Orca and Valdez groups. Similar types of occurrence are found in Kenai Peninsula in what is probably the extension of the same groups of sediments. Some gold deposits have also been found on Kodiak Island. None of these deposits are known to have such marked association with intrusive rocks as has been noted in the metalliferous veins of southeastern Alaska.

That part of the Iliamna region which lies adjacent to Cook Inlet is occupied chiefly by sediments and volcanic rocks of Mesozoic age, which are thrown into broad open folds. On the west the Mesozoic is bounded by a broad belt of granitic rocks locally altered to gneisses and probably intruded chiefly in Jurassic time. Within tlio granite area are some small belts of metamorphic greenstones, limestones, slates, and cherts, whi.ch may be Paleozoic but whose ago is undetermined. Volcanic rocks and sediments, cliiefly of Mesozoic age, lie

48 Mineral Resources Of Alaska, 1910.

adjacent to the granite on the west. These form the country rock of much of the shores of Iliamna and Clark lakes. In this field there are also some very extensive Tertiary and recent volcanic rocks. In the Iliamna region there are some auriferous and cupriferous ore bodies which occur chiefly in the altered sediments of Paleozoic or younger age at and near the contact of intrusive rocks. Some placer gold has been found in the Mulchatna basin, lying west of Lake Clark, but its geologic association is not known.

Mezozoic and Tertiary sediments and volcanic rocks, so far as known, form the country rock of much the larger part of the Alaska Peninsula and adjacent islands. The typical structures seem to be open folds with considerable faulting. Granitic intrusive rocks have not been found in that part of the. Alaska Peninsula which has been examined, and there is but little evidence of metallization. The Aleutian Islands are unsurveyed and geologically almost unknown. It seems probable, however, that they are largely built up of volcanic rocks, of which a part are certainly recent, some may be of Tertiary age, and some are as old as the Mesozoic. Some intrusive granite stocks occur in this province.

The developed metalliferous deposits of southwestern Alaska are confined to Unga and Popof islands, where auriferous veins occur in lavas, probably of Mesozoic age. Some auriferous mineralization is, however, known at other localities, notably on Unalaska Island, where it is found in volcanic rocks (probably Mesozoic) near the contact with an intrusive stock of granite.

Copper River Region.

Tile Cliugach Mountains, which bound tlie Copper Kiver basin on the south, are made up of closely folded sediments, more or less altered and intruded by igneous rocks, and carry some auriferous deposits. Tlie broad alluvium-iilled Cliitina Valley, between the Chugach Mountains on the south and tlie Wrangell Mountains on the north, separates two provinces whose geology is quite different. (See PI. III.) Tlie Wrangell Mountains are probably formed by abroad syncUne or synclinoriuni. Along the south arm of this syncUne the sequence consists of a series of ancient volcanic rocks (Carboniferous or Triassic), calhul the Nikolai greenstone, succeeded conformably by the Cliitistone limestone (Triassic), and this in turn by several formations of Mesozoic sediments capped by a great complex of volcanic rocks, w-hich are in part recent and in part may be Tertiary. The north arm of the syncline, as exposed in the upper basins of Wliite, Cliitina, and Xabesna rivers, shows Carboniferous limestones and greenstones, succeeded by Mesozoic beds, and these in turn by the recent volcanic rocks. Mesozoic intrusive rocks are fairly abundant in these formations. Tlie direct correlation of tlie older beds on the two arms of the syncUne has not been possible with the

Geologic Features Of Metalliferous Lodes. 49

information at hand. On the west the Wrangell Mountains fail off to tlie broad gravel-filled basin which stretches from the Copper to the Susitna basin.

Tlie best-developed ore deposits of tliis region are the copperbearing lodes occurring along the southern flank of the Wrangell Mountains and chiefly in the basins of Kotsina and Chitina rivers, which are tributary to the lower Copper. These deposits occur in the Nikolai greenstone and Chitistone limestone, principally near the contact of the two formations. (See PI. VI.) Copper occurs also on the northern flank of the Wrangell Mountains, in the basins of Wliite River and of tributaries of the Tanana, where the associated sediments are, however, probably chiefly Paleozoic, and some of these deposits are along contact zones of intrusive diorite. The gold of the Nizina placers, in the upper Chitina basin, has been derived from quartz veins occurring in Upper Jurassic sediments near contacts with quartz diorite intrusive rocks.

North of the Wrangell Mountains lies a belt of closely folded Mesozoic sediments which constitute the Nut zo tin Mountains. To the west these mountains merge with the Alaska Range, but there appears to be a marked change in their component strata. In the basin of the Chistocliina the foothills of the Alaska Range are made up of upper Paleozoic sediments and volcanic rocks, with later intrusives. This series is separated by a great fault from a belt of metamorphic schists which constitute the greater part of the mountains to the north. On tracing these mountains westward, the geology is again found to change. In the upper Susitna basin the southern mountain front is made up of Mesozoic slates and greenstones of undetermined age which have been invaded by large masses of granitic rocks. In the heart of the range, however, the metamorphic schists are believed to dominate.

The gold of the Chistochina placers, in the northern part of the Copper River basin, appears to have been derived from quartz veins in Carboniferous sediments in a contact zone of intrusive granodiorites. No lode deposits have been developed in tliis field, but in the Nabesna basin, 60 miles to the east, some work has been done on a lode which appears to be a mineralized zone between a granodiorite and contactmetamorphosed Umestone. The Valdez Creek placers have derived their gold from slates which are probably of Mesozoic age. These slates, like those of the Juneap gold belt, are separated from the granitic intrusive rocks by a zone of highly metamorphosed sediments.

Susitna And Matanx7Ska Basins.

The region lying north of Cook Inlet falls into two general geologic provinces, separated by the Susitna Valley. (See PL III.) On the east are the Talkeetna Mountains, made up largely of granitic intrusive

98319— Bull. 480—11 4

50 Mineral Resources Of Alaska, 1910.

rocks believed to be chiefly of Mesozoic age, with a marginal 7/)ne of metamorphic sediments. Along the southern flanks of these mountains; drained by Matanuska River, Eocene coal-bearing beds and Jurassic and Cretaceous sediments and volcanic rocks, with possibly some Paleozoic sediments, have been found. These formations, where they lie against the granite, are intensely deformed and faulted. Toward the central part of the Matanuska Valley, however, the Tertiarv beds and associated Mesozoic sediments are less disturbed but are cut by many intrusive rocks. Some Tertiary (post-Eocene) volcanic rocks are. also found in this province. The metamorphic sediments of the Chugach Mountains, already described, form the southem boundary of the Matanuska Valley.

The geology of the region north of the Talkeetna Mountains is but little known. The bedrock appears to be in part metamorphic sediments, in part little-altered Mesozoic sediments and volcanic rocks.

Some auriferous deposits have been found along the margins of the Talkeetna intrusive rocks. Those developed include the gold placers and lodes of the Willow Creek district. (See pp. 139-152.) Copper deposits are also reported in this province.

The Alaska Range, which bounds the Cook Inlet depression on the west and north, is made up of Paleozoic and Mesozoic sediments thrown up into a broad synclinorium, along the west limb of which there has been profound thrust fault/ing. These sediments are cut by many large stocks of granite and some of more basic rocks. Though the granitic rocks are of the same type and age as those of the Talkeetna Mountains, they differ in appearing to have brought about but little contact metamorphism. A series of closely folded slates, provisionally assigned to the Paleozoic, occurs along the eastem foot of the Alaska Range. These are believed to form the bedrock of the Yentna placer district, and the occurrence near by of large intrusive masses of granitic rocks suggests a genesis of the auriferous deposits similar to that described for other parts of thoTerritorv'. The slates are succeeded by a great complex of Jurassic volcanic rocks, with some sediments (Skwentna gi*oup), which are locally auriferous, though they have not yet yielded any commercial deposits. Jurassic slates and graywackes (Tordrillo formation) rest on the volcanic rocks unconformably. Some auriferous mineralization is reported to occur along the contact zones of these slates and the granitic intrusive. The Jurassic sediments have also been recognized along the west arm of the syncline, but here the volcanic rocks (Skwentna group) are absent and the Jurassic sediments rest unconformably on Paleozoic sediments made up of Ordovician, Devonian, and possibly Silurian (Tatina and Tonzona groups) and Carboniferous (?) (Cantwell formation). Some little-disturbed Tertiary coal beds occur along the eastern margin of the range, Tertiarj- beds are

Geologic Features Of Metalliferous Lodes. 51

also involved in the profound dislocations along the western base of the range. The Mesozoic beds which form the central part of the synclinorium in the southwestern part of the range do not extend through to the Broad Pass region, where there appear to be only Paleozoic rocks. To the east along the range the recognizable Paleozoic sediments appear also to die out, for the main range in the Valdez Creek region, as already stated, seems to be made up largely of metamorphic schists (Birch Creek ?) and granites. The western extension of this schist passes north of the main range in the Nenana basin and here appears to be auriferous, for it forms the bedrock of the Kantishna placer district.

Yukon And Kuskokwim Basins.

A series of highly metamorphosed sediments of great thickness, called the Birch Creek schist, forms the oldest rocks of the Yukon basin and is probably of pre-Ordovician age. This series is typically made up of quartz-mica schists and mica schists. A common phase is a micaceous quartzite. It also includes crystalline limestones and some greenstone schists which are altered igneous rocks. Gneissoid granites are extensively developed here and there in the schist areas.

The Birch Creek schist is typically developed in the Yukon-Tanana region, where it occupies a broad belt striking westward from the international boundary through to.Fairbanks, on Tanana River, forming the country rock of the important placer fields of this province- (See PI. IV.) North of the Yukon a second belt of schists, of a similar type and probably of the same age, extends westward from the Cliandalar placer and lode district into the Koyukuk placer district. Another belt of schists about which little is known but which are probably of the same age occurs in the Kaijruh Mountains. These mountains lie between the lower Yukon and Innoko districts, which are known to be auriferous, though no commerical placers have been found in tliis region as yet. This belt probably crosses the Yukon above the mouth of Melozitna River and stretches tlu-ough the unsurveyed area lying between the Yukon and the Koyukuk. In Fairbanks and Chandalar, as well as in other districts, auriferous quartz veins have been found in the Birch Creek schist. The auriferous mineralization, both in the lode and placer districts, seems to be closely related to granitic intrusive rocks. The age of these granites is probably Mesozoic and is known to be in part Upper Cretaceous.

In the Yukon-Tanana region the Birch Creek schist is succeeded unconformably by many thousands of feet of Paleozoic sediments ranging in age from Ordovician to late Carboniferous. It is beyond the scope of this paper to describe in detail the formations which go to make up this great sequence. Before Upper Devonian time there was a period of diastrophism which deformed the beds

52 Mineral Resources Of Alaska, 1910.

previously deposited, and these older formations are known to be locally mineralized and to form the source of some of the placer gold. These older beds are also developed in other parts of the Yukon region and adjacent portions of the Kuskokwim basin.

The Mesozoic is represented in the Yukon region by some Triassic limestone and in the Yukon and Kuskokwim basins by widely distributed clastic rocks with some volcanic rocks of Lower Cretaceous or Jurassic age. These rocks are especially well developed in the lower Yukon, Koyukuk, and Kuskokwim valleys and in the Norton Bay region. In the Yukon-Tanaria region these Jurassic or Cretaceous rocks do not seem to be loci of important ore deposits, though they are known to be locally mineralized. On the other hand, the gold of the placers of the Innoko-Iditarod region seems to have been derived from contact zones of these Mesozoic sediments and intrusive granites. (See pp. 243-246.) The same is probably true of the Bonanza Creek placers, on Norton Bay.

The only other hard-rock formations of tlus province are the Eocene and Upper Cretaceous strata, carrying lignitic and subbituminous coal. These beds appear to be widely distributed but do not occur . in any large areas. As a rule they do not seem to be metallized, but in the Rampart region some Upper Cretaceous beds have been found which are cut by granite, and near the contact there are some small pyritized quartz veins.

Sewabd Peninsula.

The Mesozoic sediments stretch westward from the lower Yukon until they lap over on the Paleozoic and older rocks of Seward Peninsula. These Paleozoic rocks constitute a series of varied composition, ran<]n.i2; in from Cambrian to Carboniferous. They appear to rest on an older series, made uj) of dusts and crystalline limestone and called the Kio:luaik group, wliicli may be of pre-Paleozoic age. Granitic stocks have been found in tliis older grou]), as well as cutting limestones as young as Carboniferous. There arc also some sdiists, which are altered igneous rocks, infolded with the sediments of (lifTerent ages. In the northeastern part of the Mesozoic or Tertiary volcanic rocks are extensively developed. A few small areas of Mesozoic or Tertiary lignitic coal-bearing rocks also occur on Seward Peninsula, as well as Quaternai y lava flows.

The placer gold of Seward Peninsula appears to have been derived largely from contact zones of Paleozoic limestones and . There are also knoAvm occurrences of auriferous mineralization in slates and quartzit-es. In neither case can the mineralization be directly traced to the influence of intrusive rocks. The peninsula contains, liowever, some tin deposits, which are directly associated with granite stocks intruded in the Paleozoic sediments.

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Geologic Features Op Metalliferous Lodes. 53

Nobthebn Alaska.

The geology of northern Alaska is but imperfectly known. On the Kobuk have been found metamorpliic sediments, probably representing the same horizons as those of Seward Peninsula, which are, locally at least, auriferous. (See pp. 271-319.) There are also large areas of folded Mesozoic sediments that probably represent the same horizons as those of the lower Yukon.

Near Cape Lisbume occur Carboniferous limestones carrying highgrade coal, some clastic rocks provisionally referred to the Devonian, and a great thickness of folded Jurassic beds, which carry extensive deposits of subbituminous coal. Tertiary beds are also known to occur in this province.

In the section exposed along the Colville and its tributaries Schrader found a central area occupied by rocks of varied lithology and unknown age. South of these are the metamorphic schists of the Koyukuk basin, already described, and to the north are some closely folded and Carboniferous limestones (Lisbume formation) and a heavy conglomerate and slate series of unknown age. North of the mountains these Paleozoic rocks pass underneath gently folded Mesozoic sediments, and these, in turn, under Eocene sediments. Throughout this section there is a striking absence of intrusive and volcanic rocks, and no metal deposits have been found. It is reported by prospectors that crystaUine schists occur to the east, near the international boundary, and that some placer gold has been found there.

Outline Of Geologic History.

Introduction.

What is known of the areal distribution of the larger stratigraphic units and their associated metals has been briefly presented in the foregoing pages. In this section will be given an outline of some of the more important events of geologic history which have produced these deposits. Many of these events will be very briefly touched upon, as they have only an indirect bearing on the subject considered, but special emphasis will be laid on those occurrences of the geologic past which are beUeved to have contributed directly to the formation of ore bodies. It will be impracticable to attempt to correlate all the events of the geologic history of different parts of the Territory; therefore the history will to a certain extent be recounted by districts, taken in order from south to nortli.

Pbe-Paleozoic And Paleozoic Time.

Pacific seaboard. — A number of stratigraphic units, made up chiefly of limestones, cherts, and slates and ranging in age from Silurian to

54 Mineral Resources Of Alaska, 1910.

Carboniferous, have been recognized in the Paleozoic rocks of southeastern Alaska. These represent periods of deposition which were probably interrupted by folding and erosion but need not here be considered in detail. In late Carboniferous or early Triassic time there were in this province extensive extravasations of the basic eruptive rocks, which are now found interbedded with sediments. The metallization all seems to have taken place in post-Paleozoic time.

The broad belt of more or less metamorphosed sediments which skirts the Pacific seaboard from St. Elias westward to Kenai Peninsula (Valdez group) is probably of Paleozoic age or includes some Paleozoic rocks, but the Paleozoic histor\ of this belt is obscure and need not be considered here, as the metal deposits of these rocks are probably of post-Paleozoic age.

Copper-Susitna region, — Records of Paleozoic sedimentation in the Copper-Susitna region are exceedingly meager, for only rocks of Carboniferous age have been definitely recognized. These are chiefly Umestones or volcanic rocks, and there is no evidence that they were deformed, intruded, or metallized in pre-Mesozoic time. On the inland slope of the Alaska Range many thousands of feet of Paleozoic rocks were deposited. Thase have been divided into four groups, ranging in ago from Ordovician to Carboniferous. Sedimentation was interrupted by several epochs of folding, followed by erosion. None of tliesc rocks show ovidonce of mineralization in Paleozoic time, and their oarlicM* geologic history' is therefore not pertinent to this discussion.

Yukon and Kiukohvini ha,nns. — Little is known of tlie sequence of events by which the Birch Creek schist —the oldest formation of the Yukon basin — was formed, but it consists certainly for the most part of sediments deposited in early Paleozoic or prc-Paleozoic title. After the deposition and induration of these sediments they were invaded by igneous rocks of various types and still later, but probably in pre-Ordovician time, they were intensely deformed while under a heavy rock Before this deformation and possibh' accompanying or inmiediately after the igneous intrusions, cjuartz veins were injected, some of which appear to have been metalliferous. These veins were folded and broken by the deformation and now occur chielly as stringer-s, thin lenses, and vug, which constitute the oldest system of veining in the region and do not seem to be of economic importance. Uplift and a long period of erosion of this complex seem to have taken place before the deposition of the oldest known Paleozoic formation of this field, which has been assigned to the Ordovician. The important auriferous mineralization of the Birch Creek schist, as will be siiown below, is believed to have taken place in Mesozoic time.

aEOLOGlO FEATURES OF METALLIFEROUS LODES. 55

The sequence of geologic events in the Yukon region during Paleozoic time up to the Middle Devonian is far from being established. It is known that there were long periods of deposition interrupted by epochs of erosion, and the resulting strata have been divided into several rock groups, including some which are known to be Ordovician, some Silurian, and some probably Lower Devonian. There appears to have been no notable metallization of these rocks during these periods of diastrophism. The Middle Devonian is characterized by a siliceous Umestone which is very widely distributed in Alaska and which in the Yukon-Tanana region is associated with a great tliickness of volcanic rocks, chiefly of a basic character, wliich at a later time were locally mineralized.

It is probable that after the deposition of the Middle Devonian beds there were extensive crustal disturbances, and these may have been accompanied by some quartz veining. The later Paleozoic history of the Yukon is of no significance to the problems here under discussion, and it will suffice to state that in Upper Devonian and Carboniferous time there were two periods of erosion, but that there appears to have been no interruption to sedimentation from Paleozoic to early Mesozoic time.

Seward Peninsula. — A Cambrian limestone is the lowest formation in Seward Peninsula whose age has been determined, but some schists and limestones have been found that may be older. In general, the known Paleozoic of the peninsula is represented by vast thicknesses of Umestones ranging in age from Upper Cambrian to Carboniferous. Intercalated with some of these are schists which are in part known* to be of igneous origin and various clastic rocks. The whole sequence has been so intensely deformed as to defy subdivision except after most detailed investigation.

An injection of quartz veins took place previous to this deformation, and these are now found as small irregular lenses and stringers. Many of these veins are metalUzed and some are said to be gold bearing. It is an open question whether the placer gold was derived to any extent from the older system of veining, or whether its source is largely in the younger unslieared veins referred to below. This latter epoch of auriferous mineralization is provisionally assigned to tlie Mesozoic, as is also the mineralization which produced the deposits of cassiterite, galena, etc., which are all more or less intimately associated with granites that are probably of post-Carboniferous age.

Northern Zaia Paleozoic rocks, in part of Carboniferous age, occur in the Endicott Moimtains of northern Alaska, but the sequence of geologic events in this region has not been definitely determined. A series of schists, probably of Birch Creek age, occurs along tlie northem base of the Endicott Mountains, and probably has had the same geologic history. Similar rocks occur in the Kobuk Valley. The

56 Mineral Resources Op Alaska, 1910.

fact that there appears to have been no mtrusion of igneous rocks or of metaUized quartz veins in the Paleozoic areas of the Endicott Mountains is for the present discussion the most noteworthy fact in the geologic history of this region.

Me80Z0Ic Time.

Economic importance. — From the standpoint of one interested in ore deposits, the Mesozoic was the most important era in the geologic history of Alaska, for nearly all the metallization wliich has formed commercial deposits and to wliich age assignment can be made falls within it. The time of most intense and widespread metallization can probably be still further limited to the Jurassic or Cretaceous and was thus synchronous with the mineralization which produced the valuable deposits of California and other parts of the western Cordillera. Therefore most of Alaska's metallic deposits belong to the same metallogenetic province as those of the western United States. It is not to be understood by this that the ore deposits are in any sense confined to Mesozoic horizons, for this is far from being the case. In fact, except in southeastern Alaska and in a few other districts the metalliferous deposits occur chiefly in pre-Mesozoic rocks. The mineralization which caused ore deposits took place, however, in Mesozoic time.

Stratigraphic sequence, — Sedimentary and volcanic rocks of Triassic age are widely distributed in Alaska. In general the Triassic ap])ears to have been a period of Umestone deposition, witli possibly some local volcanic outbursts. So far as there are only a few localities where ore deposits occur with Triassic rocks. The most noteworthy of these are in the River region, where copper deposits occur in the Chitistone limestone, of Triassic age, and in an older series of ancient hiva flows (Nikolai greenstone), of either Triassic or Paleozoic age.

The Orca group, of Prince William Sound, is perhaps Triassic, but it is not possible now to speak with ])recisi()n in regard to its age. It can be subdivided into a lower member, in which ancient volcanic rocks dominate, wftli some clastic rocks, and an upper member, in which slates and graywackes dominate, with some volcanic rocks. The lithology of these rocks is very different from tliat of the Triassic rocks of other parts of Alaska, where calcareous deposits are the rule and the chistic and volcanic rocks are the exception. Sedimentation was closed at about the end of Triassic time by a widespread crustal movement, followed by erosion.

During Jurassic time deposition of fragmental material took ])lace over niuch of Alaska. Many thousands of feet of sandstones and argdlites, with some volcanic rocks, were laid down, and sedimentation was probably interrupted by periods of erosion. Tlie Jurassic history is complex and need not be considered for the purposes of

Geologic Features Op Metalliferous Lodes. 5Y

this report. One phase of it wliich deserves mention, however, is the volcanic outburst m the southwestern part of the Alaska Range and in the Alaska Peninsula. The rocks of this epoch are locally auriferous, though they have not yet been the source of any large amount of gold. In late Jurassic and early Cretaceous time extensive deposits of argillaceous and arenaceous sediments were accumulated over much of Alaska, and these were subsequently folded and more or less altered. These Jurassic and Cretaceous sediments are important loci of gold deposits in southeastern Alaska and elsewhere. They appear to form the youngest beds which have yielded any commercial ore bodies, though some evidence of mineralization has been found in rocks as young as the Upper Cretaceous.

Intrusive rocks. — The genesis of most of the Alaskan ore bodies is more or less directly traceable to the influence of intrusions which took place during Mesozoic time. During this period of intrusion probably most of Alaska south of the Endicott Mountains was injected by igneous rocks. The intrusions began in early Jurassic time, possibly in some parts of the region in Triassic or even in late Paleozoic time, and culminated during Lower Cretaceous time, but continued in some places into the Upper Cretaceous. This epoch of volcanism followed and accompanied crustal movements which were continental in their effect and as a result of wliich many of the main structural Unes were established. Along these lines, however, some movements took place later.

The great batholiths of the Coast Range of southeastern Alaska were probably intruded during Jurassic and Cretaceous time. The northwesterly extension of this same belt of intrusive rocks carries them into the Alaska Range, where large stocks of igneous rocks are common. All these intrusive rocks show the same Uthologic facies, ranging from granites to diorites in composition. Rocks of the same varieties and of approximately the same age of intrusion are found in the bathohths of the Talkeetna Mountains, north of Cook Inlet. Granitic rocks are abundantly developed in the Iliamna region, some of which, however, may be of Paleozoic age. Mesozoic granitic intrusive rocks are also found in the lower Yukon and Kuskokwim basins and in the Norton Bay region. The age of the granites of Seward Peninsula is imknown, but they are, in part at least, later than rocks known to be of Mississippian age and are proba})ly Mesozoic. It is impossible to speak with precision as to the age of the granitic rocks of the upper Yukon basin. At one locality they cut Upper Cretaceous rocks, and the presumption is fair that they are in greater part of Mesozoic age and to be correlated with those of the other parts of Alaska whose age has been more definitely fixed.

In addition to the granular intrusive rocks, dikes of similar chemical composition but differing mineralogically occur in many parts

68 Mikeral Resources Of Alaska, 1010.

of Alaska and seem to belong to the same period of intrusion. This period of intrusion was probably long continued in some parts of the province, where there were probably several series of intrusions, the later ones being injected after the first had been solidified and fractured. Thus, in southeastern Alaska the main granitic masses were fractured and injected by acidic aplitic dikes, which represent the last phase of this epoch of volcanism. Similarly, the metalliferous quartz veins were introduced after the igneous intrusives — in fact, after these were solidified and fractured. The genesis of the quartz veins is therefore probably related closely to that of the granite.

The wide distribution of the metalliferous de))osits in the contact zones of the igneous and country rock has already been pointed out. The gold and copper deposits of southeastern Alaska and of the Uiamna region, the gold deposits of the Nizina, Yukon-Tanana, Chistochina, Yentna, Willow Creek, Koyukuk-Chandalar, Innoko- Iditarod, and possibly those of Prince WiUiam Sound and Kenai Peninsula, all appear to be genetically related to the Mesozoic intrusive rocks. In fact, the auriferous depositsof Seward Peninsula are the only ones for which there does not seem to be some rather clear evidence that their mineraUzation is genetically related to igneous rocks, and in most of the auriferous districts there is good reason to believe that the intrusions took place in Mesozoic time.

Tertiary And Quaternary Time.

The geologic history of Tertiar}' and later time bears only indirectly on the occurrence of metalliferous lodes. The Eocene was essentially an epoch of lacustrine and fluviatile conditions, when extensive de])osits of coal accumulated. This was followed by a period of diastrophism, in which most of the folding of the rock strata now visible took place and was accompanied by some basic intrusion and extravasation of volcanic rocks. So far as known, there was no mineralization during this period of deformation. It is, however, important in the consideration of the distribution of the metals, because it determined in many districts the attitude and areal distribution of the beds which the metals are associated.

Late Tertiary and Quaternary history is with eoloc interest but has little bearing on the present chscussion. Its later phases had to do with the accumulation of the alluvium in which the gold placers occur. In the Quaternary, too, occurred an epoch of glaciation which removed from the mountains of the coastal system, and to a less extent from those of northern Alaska, the debris resulting from the previous weathering, and in some channeled the drainage courses. This phase of the geologic history has one important bearing on the lode mining, inasmuch as the glacial ice, in part at least, removed the upper zone of rock material in which

OEOLOGIC FEATUBES OF METALUFEROtJS LODES. 69

the secondarily enriched mineral deposits should be found. It is probably safe to conclude that in most places where glacial scouring was active no deposits which have been secondarily enriched by surface waters occur;* in any event, no such deposits have yet been recognized in Alaska except at very shallow depths.

The Ore Deposits.

Intboduction.

For the purpose of systematic description the lode deposits will be thrown into several large groups, each of which will be made to include all the deposits chiefly valuable for a certain metal. Within each group further subdivisions will be made, based primarily on geologic association and only secondarily on considerations of mineralogy and genesis. This rough classification will, it is beUeved, serve the present purposes and will accord with the limitations placed on this discussion, both as to length and as to precision of data used. It will, at least, have the merit of making no pretense at anything except inmiediate utility and will leave a clear field for the formulating of a genetic scheme of classification by those who have made a more exhaustive study of the subject than the writer has,

Gold.

Outline.

The gold-bearing lodes which are more or less closely associated with intrusive rocks form by far the most important group of auriferous deposits in Alaska, and these intrusives are, as has been shown, chiefly if not wholly of Mesozoic age. A second group of gold deposits which for the present will be regarded as distinct, comprises those of Seward Peninsula, for these are not known to have a genetic relation to intrusive rocks. Each of these larger groups can be further subdivided in accordance with the country rock in which they occur and the character of the openings in which they were deposited. Thus, those associated with igneous rocks will be subdivided according as they occur in the intruded or in the intrusive rock. Each of these subdivisions can be further separated into fissure veins, impregnated zones, and stockwork deposits. It will be evident from what follows that there are some mixed types of deposits which it will be difficult to fit into this scheme of classification.

DEPOSrrS ASSOCIATED WITH INTRUSIVE ROCKS.

General Statement.

The auriferous deposits of southeastern Alaska, as already out, furnish the best examples of the close association between Mesozoic intrusive rocks and ore bodies. Tliis fact is well illustrated

1 It wiU be evident that other actors, such as temperature of water, and hence climate, presence or absence of Tegetation, alM enter into the problems connected with secondary enrichment, but these will not be conakleradbere.

ItflNERAL RESOURCES OF ALASKA, 1910.

by the geologic map of tliis province (PL II, p. 46), on which the localities of auriferous ore bodies are indicated. These ore bodies, while they bear a close relation to the mtrusive rocks, do not occur in the zone of igneous metamorphism but in the adjacent sediments, which are less highly altered. This seems to be true of all the deposits. In those lodes which lie close to or at the contact of intrusive rocks there is as a rule no great amount of igneous metamorphism.

LODE DEPOSITS DT THE nTTRUDED ROCEB.

The best-developed auriferous deposits are those of the Juneau gold belt, which, according to Spencer,* occur in a well-defined lode system that skirts the mainland both north and south of Juneau. The country rock is chiefly argiUite, with some igneous rocks, which can be collectively ' classed as greenstones of late Paleozoic or Mesozoic age and lie close to, though not in contact with, the Coast Range batholith.

The dominant ores are those carrying free gold and iron pyrite, but pyrrhotite, chalcopyrite, galena, sphalerite, arsenopyrite, stibnite,

Shccp Mtn,

Greenstone

M B.acK Slate

Green diorlte

Figure 1. — Profile section from mouth of Sheep Creek to Sheep Mountain, Jiineati district, showing locus of auriferous mineralization. By A. ('. UK),*?.

tetraliedrite, molybdenite, pyrargyrite, and maoiotite Jiavc also been found. Quartz is the cliief ganguo mineral, but calcite and other minerals also occur.

Spencer recognizes two types of ore bodies — (1) tJie veins, which include the mineral aggregates deposited in fractures of the country rock, and (2) the impregnated zones, in whicli the metallic minerals are disseminated, more or less irregularly, through of the country rock. Some deposits, as that of the Tread well (see pp. 07-69), appear to combine both of ore These general types have also been recognized in otlier parts of Alaska.

A good example of tlie vein deposits is that on vShee]) Creek, near Juneau. Here tlie country rock is a part of the slate-jjrccnstone

Spencer, A. C, The Juneau gold belt, Alaska: Bull. U. S. (Jeol. Survey No. '2S7, liKXi, pp. 21-137.

Geologic Featubes Of Metallifebous Lodes.

series typical of. the Juneau belt, which is cut by diorite dikes. The ore bodies occur at a slate-greenstone contact near the intrusive diorite. In figure 1 the locus of mineralization is indicated by the position of the Glacier mine. At this locality three parallel veins occur in the slates, near the greenstone contact (fig. 2), and these veins, with a number of others lying farther from the greenstone contact, occupy a mineralized zone some 400 feet wide. The fissures are in general parallel to tlie cleavage, but in places they cut across it. Across the divide from Sheep

Creek, to the northwest, in the valley of Gold Creek, the same general geologic conditions for the occurrence of the ore bodies prevail. The deposits all occur in the greenstone -slate series near contacts with the intrusive rocks. Here the principal mineraUzation has produced stringer leads which are complex networks of quartz veins following two systems of fractures and constituting a deposit of the impregnated-zone type. Many of these lodes occur directly at the contact of diorite and slate, the diorite being more or less altered.

In addition to the deposits of the mainland belt some miner- aUzation has been found in the greenstones of the western part of Douglas Island. Here the country rock consists of slates and greenstones and the ore bodies consist of impregnated zones of fracture. Spencer notes that pyrite is the chief metallic mineral in these deposits, but galena, sphalerite, and chalcopyrite have also been found. Albite and rutile occur as gangue minerals.

Auriferous deposits havQ also been found in the argilUte and greenstones which skirt the mainland and adjacent islands west of the granites of the Coast Range in the Ketchikan district, south of Juneau. Here some small fissure veins have been found, but deposits of the disseminated type appear to dominate and have yielded but

lOo 200 feet

Figure 2.— Generallied cross section of Silver Queen and Glacier mines, Juneau district, illustrating the relation of the tone of mineralization to the slategreenstone contact. By A. C. Spencer, 1903.

& Spencer, A. C, The Juneau gold belt: Bull. U. S. Oeol. Survey No. 287, 1906, pp. 92-93.

62 Minekal Besources Of Alaska, 1910.

few commercial ore bodies. These deposits occur in rocks which lie adjacent to areas affected by contact metamorphism due to granite intrusion. They include some auriferous quartz veins, but the prevailing type of deposit is the minerahzed fracture zone. These zones occur especially in the greenstone schists and are characterized by an abundance of iron pyrite with but little gangue. Their gold values are usually low, but some of them carry lenses and vugs of quartz very rich in free gold.

Deposits of the fissure- vein type have also been found in many parts of the Ketchikan district but so far have yielded no very large or very rich ore bodies. Most of these occur in or are intimately associated with porphyry dikes and will be considered later (pp. 69-70).

The auriferous quartz veins of the Sitka region, described by Mr. Knopf on page 98 of this volume, cut a graywacke series, which is probably of Mesozoic age. No intrusive rocks occur in the immediate vicinity of the ore bodies, but a large stock of granite is known to lie a few miles to the east. Auriferous veins have also been found at a number of places on Prince WiUiam Sound,' notably at P.ort Valdez and McKinley Lake. Here again the association with intrusive rocks is not definitely established. On Port Valdez the bedrock consists of a closely folded sequence of slate and graywackes belonging to the Valdez group. The veins appear to follow a well-defined system of Assuring. At the Cliff mine, which is the only deposit examined, the ore is blue quartz carrying much finely disseminated pyrite with minute quantities of arstnopyrite and high vahies in free gold. Some of the veins have been crushed and recemented by quartz.

The gold-bearing veins of Kenai Peninsula appear to be similar in character. They are quartz veins carrying pyrite, and free gold. At one locality some telluride has been found.

Mr. Moffit's description of the Valdez Creek placers (pp. 119-127), in the upper Susitna region, and of tlie Cliistochina placers, both of which occur in argillites, also indicates a close relation between the bedrock source of the gold and the granitic intrusive rocks. To this type of deposit should probably also be added tiie deposits of Bonanza Creek, near the eastern shore of Norton Bay, where, however, no gold has yet been found in the bedrock.

Brooks, A. H., Preliminary report on the Ketchikan district, Alaska: Prof. Paper U. S. Geol. Sur\-ey No. 1, 1902. Wright, F. E. and C. W., The Ketchikan and WranRell mining districts: Bull. V . S. (ieol. No. 347, 1908.

Grant, U. S., and Higgins, D. F.. Reconnaissance of the geology and mineral resources of Prince William Sound, Alaska: Bull. U. 8. Geol. Survey No. 443, 1910.

Grant, U. S., and Higgins, D. F., Preliminary report on the mineral rcvsources of the southern part of Kenai Peninsula: Bull. U. 8. Geol. 8ur\'ey No. 442, 1910, pp. 1W>-I78.

Smith, P. S., and Eakin, H. M., A geologic reconnaissance in southeastern Seward Peninsula and the Norton Bay-Nulato region: Bull. U. S. Geol. Survey No. 449. 1911.

Geologic Features Of Metalliferous Lodes. 63

In the Yukon-Tanana region as a whole, but more especially in the Fairbanks district, there appears to be a close genetic relation between the gold deposits and the granite intrusive rocks. (See Fl. IV f p. 52.) At Fairbanks, where some work has been done on lodes, two systems of quartz veining have been recognized, both of wliich cut the Birch Creek schist. In addition to these, quartz stringers occur in the laminations of the schists and have been involved in the folding. The crosscutting quartz veins of the older generation appear to be larger than those of the later system, but wliile they carry some iron pyrite, the gold values appear to be low. After their introduction these veins were brecciated and the bedrock was again fractured. The openings thus formed were impregnated by mineral-bearing solutions. In this way the older system of veins was enriched and some new veins were formed. The metal contents of the deposits due to the second period of mineraUzation are free gold, pyrite, stibnite, arsenopyrite, galena, and sphalerite. Quartz is the chief gangue mineral, with some calcite and locally orthoclase, calcite, albite, and tourmaline. The general distribution of the quartz veins indicates that there is a mineralized zone which parallels the main structures of the country rock but which is not very well defined (fig. 3). There have been some recent lode developments in the Chandalar placer district, north of the Yukon, where the conditions are probably similar to those at Fairbanks and where the deposits occur in close relation to intrusive rocks.

In addition to the fissure veins the Fairbanks district contains lode deposits which are probably comparable to those of the Juneau district described as mineralized zones. These are zones of fracture in the schists which have been permeated by mineral-bearing solutions. They are characterized by networks of small metalliferous quartz veins, forming stringer-lead deposits. In some places the quartz veining is only a very subordinate phenomenon, the main mass of the deposit being made up of pyritized schist carrying some gold. Only a few assays have been made on this type of deposit, but these indicate that the gold values are low. A deposit of this kind in the Bonnifield district is described by Mr. Capps on page 230. Here the country rock appears to be an altered and highly schistose rhyoUte and not a sediment, as is the case in the Fairbanks district. It also seems probable that the gold of the placers of Willow Creek, in the Susitna basin (see pp. 145-146), has been derived from similar mineralized zones in a crystalline schist. This occurrence appears to be of a somewhat different type from those previously described, for it seems to lie within the zone of igneous metamorphism.

1 Prindle, U H-f AqrUerous quarts veb of tbe Fairbanks district: Dull. U. S. Ueol. iSurvey No. 379, 1910, pp. 210-820,

Mineral Resources Of Alaska, 1910.

Geologic Featuee8 Of Metalliferous Lodes. 65

As a general rule, the mineralized zones in the bedrock appear to occur in the schists, where the movements have not brought about notable open spacings but have formed crushed zones subsequently permeated by the mineral-bearing solutions. Such disseminated deposits seem to be more favorable to the formation of placers than where the ores occur in better-defined fissures. Where the physical character of the country rock has induced fractures with open spaces rather than shear zones, deposits of the fissure-vein are more likely to be formed.

Auriferous veins that occur in crystalline limestones, usually near the contact with intrusive rocks, form another class of ore bodies which, however, differ from some of the silver-lead deposits to be described below only in the fact that they are valuable chiefly for their gold contents. This type of deposit is represented in southeastern Alaska by a number of ore bodies which have been more or less developed on Prince of Wales Island. They occur typically in brecciated zones in crystalline and semicrystalline limestones, the openings thus formed having been penetrated by the mineral-bearing solutions and quartz and calcite, together with free gold, pyrite, chalcopyrite, tetrahedrite, galena, sphalerite, and arsenopyrite. These minerals have to a certain extent replaced the limestone, a fact which gives the ore bodies indefinite boundaries. Usually the values are distributed in shoots witliin the brecciated zone. Moffit and Knopf ' have described the Royal Development Co.'s property at Jacksina Creek, in the Nabesna basin, as a mineralized contact zone between crystalline limestone and diorite. The entire mass has been sheared and heavily pyritized. At the surface at least it carries free gold, but it is not known what the form of the gold is below the zone of weathering.

Nearly all the gold deposits which have been described occur in rocks of sedimentary origin which have been subject to the influence of granitic intrusive rocks. In southwestern Alaska there is evidence of auriferous mineralization of volcanic rocks at and near the contact of granitic intrusives. Spurr has described an example of this form of mineralization in a natural exposure on Skwentna River, north of Cook Inlet. The geologic relations are represented diagrammaticaliy in figure 4. The mineralized area in the basalt along the granitic contacts in this and other localities contains pyrite, chalcopyrite, and galena, and assays show the presence of gold.

i Wright, F. E. and C. W., The Ketchikan and Wrangell mininK districts. Alaska: Bull. U. 8. Gool. Banrty No. 347, 1908, pp. 81-S2, 166-177. Brooks, A. H., Preliminary report on the Ketchikan mining district, Alaaka: Prof. Paper U. S. Geol. Survey No. 1, 1902, pp. 51, 77-88.

s Moffit, F. H., and Knopf, Adolph, Mineral of the Nabesna- White River district, Alaska, BalL U. 8. Geol. Surrey No. 417, 1910, p. 58.

Sporr, J. E., A reconnaimance in southwestern Alaska: Twentieth Ann. liept. U. S. Geol. Survey, pi. 7, 1900, pp. 111-112. 259.

08319''— BuU. 480—11 5

66 HINERAi. BE&OUBCE8 OF ALASKA, 1910.

Evidence of mineralization in volcanic rockit of tlie same age has been found in other parts of tliis region.'

if eipoaiii* In canyon ol Stmntna Rtm-, lUosaloog ronlai't n[ granite diLe. Rj J. E. SpujT, e, Imprpgnaml by mptaULc £iilpbLd; C, Lotrus-

The only developed lode in southwestern Alaska is the Apollo mine, on Unga Island. This deposit has been deacribed by Becker ' and others as occupying a zone of fracture in a ccnintry rock of dacite and andesite. Becker considered tlie volcanic rocks as of Miocene or post- Miocene age, but Atwoud haw ciiiled tliis determination in question ami hohoves tliat they iirc certainly pre-Miocene and may be Mesozoic. Atwood also reports some dacite dikes on Unga Island, though none were ohservcd in the immediate vicinity of the ore body. The metalHl mim'nds of tlie deposit iire free gohl, chalcopyrite, galena, zinc <le, mid native C(). Other deposits of similar chanicter have been notcil in the iicighhorhooil. There Ls no direct evidence of the influence of intrusives on this mineralization.

Some auriferous minenilizalion has idso been on I'nalHska Island, at the east end of the Aleutian chain. Here the bedi-ock consists of anih'sitic voU'anic i-ocks, whose age is unkniiwn but is probably Mesozoic. A large graiiili<' stock lies near tliis occurrence, and there is evidence that it lias had some miuiTaliziug uifluence.*

Lode Deposits Iit The Uttscsive Rocks.

The lode deposits in the intrusive n'ks include lliosi zones in mas.sive granite or dii

bear 1 also mineralized dikes. A

1 Brooks, A. H,. The Mount ,Mi-KUiley

'Blon, Alasku: ;uU lleHs oF so

vey No.

.-, pji. 1

U. 8. C.eol. No.

pp, loz-ios.

I Juggai, T. A., Jonmul ol Uw Technology expedUion In Tech, Rtvifw. vol 10, No. 1, pp, 17-ID.

he Alfullan laWidf

Qeolooic Peatuees Op Metalliferous Lodes.

good example of the first type b found in the Kensington lode, in the Bemers Bay region of southeastern Alaska. According to Knopf ' the ore body consists of an irregular mass of crushed diorite, marking a zone of movement witlun massive diorite walla (fig. 5). This fracture zone has been gashed by a multitude of quartz stringers, forming a stockwork deposit. It carries pj'rite and, in at least one place, a little galena. More or less alteration of tlie diorite walls of the lode was noted. The outcrop of the Kensington lode is about half a mile east of a slate-graywacke series of Jurassic or Cretaceous age into wliich the diorite is intrusive. According to Knopf there are also well-defined fissure veins withiii the diorite of the Bemers Bay region.

FiomE t.— Dlsgrammi

B Bay, ehowlng a'

The ore deposits of the Treadwell group of mines also belong to this t}'pe of deposit, but the relations are not as simple as those at the Kensington. These mines, which are located on Douglas Island, near Juneau, and have produced over $40,000,000 worth of gold, form the laiest mining enterprise in Alaska and one of the largest in the world, and their ore deposits will therefore bo described in some detaU. The following account is abstracted from Spencer's report : '

The ore bodies consist essentially of fractured and mineralized diorite dikes, which have penetrated a black slate parallel with and close to a greenstone contact (fig. 6). The greenstones a|)pear to be altered volcanic rocks, and they, with the slates, constitute a part of the series which forma the country rock of much of tlie Juneau gold belt and is now regarded as probably of Jurassic or Cretaceous age. The fracturing of the diorite dikes has given opportunity for the mineralizing solutions to penetrate, and these liave formed an intricate and irrular network of veinlets which can be designated as stringer leads. In addition to tliis, tlie ore-bearing solutions have permeated

1 KnopI, AdDljA, OcolDgy of the Bemers Bay All PP.KM2. Spcnoa, A. C-, The Jodhki gold belt: Bull. U. 3. Qeot. Surveji

Dull. U. 3. Gnl. No. 41C, 1911, 2X7, lew, pp. 88-11&

Mineral Resources Of Aiaska, 1910.

the diorite dikes, which have been largely altered to a mass of secondary minerals and vein matter. This mineralization has been traced by mine workings for almost 3,500 feet, with an extreme width of 400 feet. A depth of 1 ,600 feet has been attained without any notable change in values.

The dominating metallic minerals are free gold and pyrite, with considerable pyrrhotite and magnetite. In addition to these, chalcopyrite, galena, sphalerite, native arsenic, realgar, and orpiment have been found. Much of the gold is free, as high as 75 per cent of the assay value having been recovered. The important gangue minerals are feldspar, calcite, and quartz, with some rutile. Some of the original minerals of the diorite, such as feldspar, hornblende, and mica, are still present. Epidote, an alteration product of the primary minerals, is also found.

Gastineaxt

J\/neau I

CHANNEL readvell

Ceqend

greenstones

BleMhed and pyritSnd greenstones

Mainshaft

1 Alasks-Traedwdl

3 Alaska-Mexican

4 Rea4yBuUkn

2 Miles

Figure 6.— Geologic sketch map of northwest end of Douglas Island. By A. Spencer, 1903,

The Treadwell ore bodies in tlieir mode of origin and form of occurrence do not differ from some of the other deposits of the Juneau gold belt. Spencer has described the diorite adjacent to some of the lode deposits on Gold Creek as altered and more or less mineralized. It appears that in the Treadwell deposits the entire diorite mass was crushed, and the fractures thus formed gave opportunity for the mineral-bearing solutions to circulate, and the process continued until the whole dike was impregnated, while in deposits of the Kensington type the mineralization followed zones of crushing included within walls of massive igneous rocks.

Some auriferous veins have been found in a massive countr> rock of granite near Karta Iake, on Prince of Wales Island, in the Ketchikan district. These veins follow fissures with well-defined walls and have a marked regularity in direction and thickness. In some places

Wright, F. E. and C. W., The Ketchikan and WrangcU mining districts, Alaska: Bull. U. S. Geol. Survey No. 347, 1908, pp. 164-166.

OEOIiOOIC FEATUBES OF METALUFEBOUS LODES. 69

diabase dikes have penetrated the fissures and have subsequently been fractured, and the auriferous quartz fiUing has been deposited along the spaces thus formed. The metallic vein minerals are free gold, pyrite, galena, and chalcopyrite, with a gangue of quartz, calcite, and possibly sericite.

The auriferous lodes of the. Willow Creek region, north of Cook Inlet, described by Mr. Katz on pages 144-146, also belong to this type of deposit. These occur as fillings in what appear to be well-defined fissures in a quartz diorite country rock. Martin and Katz have described a mineralized zone occurring within a granitic country rock near Cottonwood Bay, on Cook Inlet. This is described as a zone of shattering in a granite mass along which pyritiferous quartz veins have been deposited. Low gold values are reported. A mass of greenstone occurs near the ore body, and the granite is locally intruded by porphyry dikes.

At Orange Hill, in the Nabesna River basin, tributary to the Tanana, some auriferous mineralization has been found in a quartz diorite mass.' At this locality the diorite is cut by many small quartz stringers, some of them carrying pyrite and a few molybdenite. A similar deposit has been noted on Monte Cristo Creek, in the same ron, and to the east on Beaver Creek, a tributary of upper White River. Several auriferous lodes have been found in the basin of Eureka Creek, also tributary to the White, which appear to be mineralized zones of fractures in a silicified feldspar porphyry.

The presence of auriferous deposits in granites and granodiorites is inferred from the distribution of placer gold in several districts. Thus the gold of the placers of Hill Creek, in the Fairbanks district, appears to have been derived from a mineralized zone in the margin of a granite stock. Mr. Maddren's description of the placers of the Iditarod (pp. 245-270) suggests that the gold was in part derived from a granite bedrock source. The writer ' has also noted the occurrence of a mineralized zone in a granite 15 miles below Robertson River, on the north side of the Tanana Valley. Here both gold and pyrite were found disseminated in a brecciated zone about 10 feet wide, traversing a granite mass.

Mineralized dikes are not uncommon in many districts and some of these carry gold values. Such deposits have been found at the Sea Level mine and near HoUis, in the Ketchikan district.* Here the coimtry rock is chiefly greenstone and calcareous schist (Mesozoic

1 Harttn, G. C, and Kate, F. J., Outline of geology and mineral resources of the Iliamna and Clark lakes regioa: BnO. U. 8. Qeol. Survey No. 442, 1910, p. 194.

s liofflt, F. H., and Knopf, Adolpb, Mineral resources of the Nabesna- White Kiver district: Bull. U. S. OeoL Surrey No. 417, 1010, pp. 58-60.

Brooks, A. H., Reconnatesance in the Tanana and White River basins, Alaska, in 1898: Twentieth Ann. Kept U. 8. 0oL Survey, pt. 7, 1900, p. 487.

Brooks, A. H., Preliminary report on the Ketchikan mining district, Alaska: Prof. Paper U. S. Geol. Survey No. 1, 1902, pp. 66-67, 91-93. Wright, F. E. and C. W., The Ketchikan and Wrangell nUning diftrlets, AlMka: BnU. U. 8. OeoL Sunrey No. 347, 1908, pp. 14146, 160-161.

70 ' Mineral Resources Of Alaska, 1910.

or late Paleozoic), which have been crosscut by porphyry dikes. Thase dikes have, in turn, been fractured and invaded by mineralbearing solutions that deposited galena, sphalerite, with some native gold, and quartz and a little muscovite as gangue minerals. The dike rock itself has in places been heavily mineralized.

At the Cracker jack mine, near Hollis, the country rock is slate, more or less graphitic, which has been invaded by a porphyry dike. The ore body lies adjacent to this dike, but the dike itself has been epidotized and pyritized. The ore carries pjTite, galena, sphalerite, and an undetermined black antimony or bismuth mineral, with quartz and a little calcite as gangue minerals. In both localities there are deposits of similar types which are not so intimately associated with the dikes.

A pyritized dike rock, which is associated vith an auriferous lode deposit in the Moose Pass district of Kenai Peninsula, has been described by Grant and Higgins.* The dike is made up of a finegrained aggregate of plagioclase, quartz, mica, and probably orthoclase, with scattered cr}'stals of arsenopyrite. The mica is of a lightgreen color and is secondary after the feldspar. Maddren* has noted pTitized (likes which carry gold in association with quartz veins in the Innoko district. In this field intrusive granites are known to be close at hand.

Lodes Of Sewabb Peninsttla.

The old-bearing lodes of Seward Peninsula arc here described separately because it can not be proved that they bear a genetic relation to intrusive rocks as do most of those already described. Smith to be sure, considers, that the intrusive granitic rocks of the Kigluaik Mountains were injected at the same time as some of the quartz veins of the Solomon-Casadepaga reciou. He also cites the presence of tourmaline in many of tlie rocks as evidence tliat granitic intrusives may imderlie areas where they do not outcrop. The facts remain, however, that in those parts of the wliich, from the of placer gold, must have been heavily mineralized no granitic intrusive rocks have been found and that no auriferous deposits have been foimd in the ngions which are known to have been intruded by granite. Moreover, the type of mineralization in areas that have been invaded by granite has not produced ore bodies valuable for gold but deposits carrying thi, tungsten, galena, etc., and these (see pp. 87-90) ap])ear to differ essentially from the veins and mineralized zones which have yielded the placer gold. It is therefore at least an open question whether this auriferous mineralization bears any direct genetic relation to the granitic intrusives.

1 Grant, U. S., and , D. F., Preliminary report on the mineral resources of the soullu'rn juirt of Kenai Peninsula: Bull. U. S. Gcol. Survey No. 442, 1910, pp. 171-172.

*Maddren, A. The Innoko gold plawr district: Bull. U. S. (Jeol. Survey No. 410, 1910, p. (4.

Smith, P. S., Geology and mineral rosourees of the Solomon and Casadepaga quadrangles: Bull. U. S. Geol. Survey No. 433, 1910, pp. 132-133.

Geologic Features Of Metalliferous Lodes. 71

The writer has shown elsewhere that the auriferous lode deposits of Seward Peninsula can be classed in two general groups — fissure veins and bnpregnated zones of fracture. There is also an older series of quartz veins, which lies parallel to the foUation of the schists and has been deformed with them, and these, too, locally carry sulphides and gold.

The distribution of the gold placers in the peninsula has helped to indicate the locus of auriferous mineralization in the bedrock where no other direct evidence was available. This class of evidence goes to show that, in the peninsula as a whole, the limestone-schist contacts were the most favorable places for auriferous mineralization.* An example of the relation of the mineralization to the limestone-schist contact is shown in the accompanying sketch map of the Ophii- Creek region (fig. 7). The distribution of the placer gold at this locality indicates that it had its source in the limestone-schist contact. Moreover, at several places where this contact was studied in the field evidence of shattering and mineralization was observed. (See section A-B, fig. 7.)

Smith ' has described the mineral veins of the Solomon-Casadepaga region in considerable detail, and those of tlie rest of Seward Peninsula are probably similar to these. He shows that there is an older system of quartz veining which may have been formed at a number of different periods of intrusion, all previous to the last epoch of intense deformation. The rock movement deformed tlie veins, wliich are now represented by blebs and bimches of quartz, irregularly distributed along the planes of foliation.

Besides being intensely folded and broken, the veins were crushed and then more or less recrystallized. The older veins are most abundant in the schists but occur also in the limestone, where they have usually not been much deformed. Metallic minerals are not common in these deposits, but some of them carry a little gold, some a little sulphide, and some rutile. Most of the younger series of quartz veins, as described by Smith, follow fissures which intersect the lamination of the country rock at different angles. These veins have as a rule suffered little deformation but are locally faulted. Some of them show comb structure and most of them have well-defined walls. These veins are again divisible into two types, one carrying locally visible free gold, with a gangue of quartz and but little sulphide, and the other carrying copper, iron, arsenic, and antimony sulpliides, with no visible free gold.

Smith states that quartz veins occur in all the formations mapped, but they seem to be most abundant in the schists and slate. It

Collier, A. J., Hess, F. L., Smith, P. S., and Brooks, A. 11., The gold placers of parts of Soward Penlnfula: Bull. U. 8. Oeol. Survey No. 328, 1908, pp. 110-139.

side, pp. 121-124. Smith, P. S., Geology and mineral resources of the Solomon and Casadepaga quadrsnei: Bull. U. S. Oeol. Survey No. 433, 1910, pp. 141-142.

Smith, P. 8., BulL U. 8. OeoL Survey No. 433, 1910, pp. 8&-93.

72 Minehai. Besoubces Of Alaska, Isio.

appears, from his work as well aa that of others, that the limestoneschist contacts afforded conditions favorable to miner&Zation. Th lithology of the country rock, however, except in so far as it affected

the character of the fissuring, does not seem to have any influonrc on the formation of quartz veins. In the Solomon the veins occurring in the Hurrah slate appear to bo most Tliis

Qboloqic Featubes Qf Metaluferous Lodes. 73

rock is well jointed and in places the deposits occur as a stockwork of veins, thus forming a transition to the impregnated zone and fracture type of deposit.

The Big Hurrah mine, in the Solomon basin, is the only auriferousquartz deposit which has been developed to a productive basis. The country rock is a hard black graphitic quartzite ' (Hurrah slate), which is much fractured and breaks into rectangular blocks. Numerous fractures occur throughout this formation and in many places it is seamed with quartz veins and stringers. These quartz veins, although they are believed to belong to the youngest system of veining, are more or less deformed. The gold of the Big Hurrah lode is almost entirety free and httle or no sulphide is present. Much of the ore is banded with flakes and layers of graphite and graphitic schist. The vein has been opened to a depth of about 250 feet without any noteworthy changes in the character of the ore.

Smith fdso describes some calcite veins occurring in or close to limestone bedrock in the Solomon region. These reins, he states, carry no metallic minerals. It should be noted,

however, that near Nome free gold fioube s-DiagramiDHticKctionDi has been found in calcite veins. r.™ biub, sewwd i

,. . , , By H. Broots, IflOS.

The more dissemmateu types of auriferous deposits of the peninsula, here called mineralized zones of fracture, are probably more common than Assure veins. In general they represent zones of fractured bedrock which have been permeated with mineral-bearing solutions. Some of these contain veins which may be stockwork or stringer-lead deposits. In others there is but little quartz and the deposit is defined by a zone of the bedrock which is heavily pyritized and in some places auriferous. Very few of these deposits are sufTiciently well exposed to permit exhaustive study. It is not definitely known whether these deposits represent the older or the younger system of veining, but they probably belong to the younger. Mineralization of this type seems to be most pronounced at the limestone-schist contacts, where its distribution was determined by the fractures resulting from movements along tlie contact planes between the two formations.

Smith ' has described the mineralized zones in the schist-limestone contacts of the Solomon and Casadepa region as consisting of replacements of Umestone by quartz with more or less sulphide minerals, of which chalcopyrite is most common. The writer's ou'n

, P. H., Qaotac7 tai mlnorsl resoiing of the Soh WIO.pp. 1M-It5. roller A.I.bdJ Ik: Bull. U. 8. Oaol. Snrve; Mo. 3S, IMS. pp. 223-231.

BnUtfa, F. 8., op. dX., pp. 141-143.

74 Mineral Resources Of Alaska, 1910.

observations go to show that at some localities the zone of mineralization may be confined entirely to the schist but close to the Umestone contact. An example of this is shown in figure 8, which is a diagrammatic section of a natural exposure near Bluff. Here a mass of schist, which is probably an altered igneous rock, is included between limestone walls. A series of gash veins cut across the foliation of the schist.. These veins also penetrate the footwall of limestone. The metalliferous minerals noted in this deposit are pyrite, arsenopyrite, and chalcopyrite and are said to carry some gold.

Outline Of Classification.

Practically all the Alaskan copper deposits thus far developed fall into five general groups determined by mode of origin or mode of occurrence. These are (1) deposits in zones of igneous metamorphism and chiefly near the contact of limestones with granodiorites and diorite intrusive rocks; (2) deposits associated with intrusive rocks, but not within the zone of igneous metamorphism; (3) deposits disseminated in intrusives; (4) deposits associated with ancient volcanic rocks and sediments; and (5) copper-bearing amygdaloids. Each of these groups admits of further subdivisions, which will be discussed later. Tliis classification is summarized below.

Classification of Alaska copper deposits.

1. Deposits in zones of igneous metamorphism,

(a) Contact-metamorphic deposits of limestones and intrusive

rocks. (6) Contact-metamorphic of clastic and intrusive rocks.

2. Deposits associated with intrusive rocks, but not in zones of igneous

metamorphism.

3. Deposits disseminated in intrusive rocks.

4. Deposits associated with ancient volcanic rocks and sediments.

(a) occurring in green.stones and argillites. (6) Deposits occurring in greenstones and limestones.

5. Copper-bearing amygdaloids.

Deposits In Zones Of Igneous Metamorphism.

Copper-bearing lodes occurring in the contact zones of limestones and intrusive rocks are among the most widely distri])uted types of deposit in Alaska. The intrusive rocks are probably of Mesozoic age. Such ore bodies are especially on parts of Prince of Wales Island, in the Ketchikan district of southeastern iVIaska. The geologic features of some of the best known of these deposits are shown on the accompanying map of the Copper Mountain region (PI. V). Here an irregular stock of granite is surrounded by limestones and

Wright, C. W., Miniug in soutbeaslecn Alaska: Bull. U. S. Geol. Survey No. 370, 1910, pp. 80-2.

u.8.aeoLjoo

Geologic Features Of Metalljfebous Lodes. 75

metamorphic schists and the copper deposits occur in the contact zone of limestone or schist adjacent to the granite. The ore bodies occur only where igneous metamorphism has taken place in the sediment adjacent to the granite, and this is by no means the case along the entire contact. Where this alteration has occurred a greenish or reddish rock has been formed composed chiefly of garnet and epidote and almost always carrying some disseminated chalcopyrite, pyrrhotite, and magnetite. This contact zone varies from 25 to 250 feet in width.

The ore bodies, which are of irregular outline and distribution, consist of chalcopyrite and pyrite in a gangue of garnet, epidote, calcite, and some quartz. They carry both gold and silver. Some of the deposits contain much magnetite; others lack this mineral but carry pyrrhotite. According to Wright the lodes were formed from solu-- tions which penetrated along the contact, along preexisting fissures, or along solution channels in the limestone, or are replacement deposits of limestone where no notable opening previously existed. The important ore bodies usually lie along the contact, but from these smaller bodies of vein material branch out, penetrating both walls locally to a distance of a thousand feet.* The deposits in the schist near the contact are usually less concentrated than those in the limestone and are usually disseminated along the planes of foliation. As a rule they do not form commercial ore bodies.

Many of the copper deposits of the east side of Prince of Wales Island, including those of Kasaan Peninsula, in the Karta Bay region, are also of the contact type. Wright's investigations* show that the sediments of this field include a series of conglomerates and gra3rwackes and tuflFaceous schists, which occur in broad areas, and narrow belts of limestones. The whole series has been folded and then extensively intruded by granular rocks which include granites, granodiorites, diorites, and syenites. These intrusives, which occur as irregular stocks and dikes, were followed by an injection of pegmatite dikes and, still later, by a widespread intrusion of porphyry dikes.

Contact deposits similar to those of Copper Mountain form the most widely distributed ore bodies of this region. They occur chiefly in the zone of igneous metamorphism at the contact of limestone and intrusive rocks. A few have been found at the contact of the graywacke-tuflF series and the intrusives. The ores of the limestone contact are chalcopyrite, pyrite, pyrrhotite, and magnetite, with a gangue of epidote, garnet, amphibole, calcite, and orthoclase. These

1 Wriit, F. E. and C. W., The KetcbUcan and WrangeU mining districts, Alaska: Bull. U. S. Geol. Survey No. 347, 1908, pp. 95-96.

s Brooks, A. H., and others, Mineral resources of Alaska— Report on progress of investigations in 1906: BulL U. S. Oeol. Survey No. 379, 1909, p. 81.

s Wright, C. W., lining in southeastern Alaska: Bull. U. S. Oeol. Survey No. 379, 19U9, pp. 76-79.

Mineral Besoubces Of Aiasea, 1910.

masses Taryiog from 10 to 250 feet

deposits are typically irruli in width.

The shape of one of these ore bodies and its relation to the intrusiTe rocks is sliown by the accompanying plan and section (fig. 9) of the workings of the Mount Andrew mine, on the southwest side of the Kasaan Peninsula. The ore bodies occur at the contact of a large intrusive mass and a belt of crystalline limestone.* In the plan and

FiouBE 9.— Plan ai

ctionorUounl Aadren-mine work ng K ti

section the altered country rock represents a mctamorphic phase of the limestone and is made up of garnet, epidote, and oaleite, together with a large amount of magnetite. This country- rock has been cut by dikes of sj'enite, wluch are probably apophyses from the main mass of intrusive rocks that lies adjacent to tlie ore body on the east. The ore is composed essentially of chalcopyrite and magnetite and carries some gold and silver.

Wisngell mining dlaUicls: Dull. U. B. Ueol. Survey

Qeoloqic Featubes Of Metalufebous Lodbb.

In this Bame region there are copper-bearing lodes wliich occur in the form of lenses in shear zones in the graywacke and tuffaceous

100 200 feet

n n a

plan ind aectloa of workloga at Rush & Drown mine, near Karta Bay, BliawlDi! on bodlM and nblloD of mlncralliatioa to contact betweea granodLotitc and (uO and conglomnile. Hy C. W. , WB.

schist series but apparently in the zone of igneous metamorphism of intrusive masses. Their metallic minerals are clialcopyritc, pyritc, and usually sphalerite, with a quartz and calcite gangue. Th Rush &

Dull. u. a. oni.

Mineral E£Sourceb Of Alaska, 1910.

1 Brown mine,' near Eaita Bay, affords

s examples of both the contact-metamoi

j phic ore bodies and those occuniDg in

shear zones. Figure 10 indicates the

° geologic relations of the ore bodies at

"" tliis locahty. These deposits furnish

I the only example thus far developed in

I this district of igneous contact deposita

I in sediments other than hmestones.

I Mofht and Knopf have described

I contac't-raotamorpluc deposits of cop-

I per which occur in the basin of upper

g Nabesna River, tributary to the Tanana.

These deposits are found in a crystalline

I limestone at or near the contact with

8 dioritic intrusive rocks. The ores are

bomite and chalcopyrite, associated with

garnet, epidote, coarsely crystalline cal-

1 cite, hematite, and scattered flakes of 1 1 molybdenite. Some of these deposits also contain magnetite. The data at 1 hand, wliich are fragmentary, as but little development work has been done,

2 uidicate that these deposits are sunilar in character to the contact deposits of I southcatcni Alaska. The copper ores west of Cook Inlet, S between lliamiia Bay and Iliamna Lake, 1 occur in a contact zone' between lime-

3 stone and agreenstonewhich isanaltered diabase or diorile. The field relations t are shown in figure 1 1. The mineralized M zone, averaging '200 feet hi width but in I places reaching 300 feet, lies chiefly in % the hmeslone but also in (lie green-

gc,c I stone. It contains cliulcopyrile, p_Tite,

I and magnetite, with a gangue of garnet,

I calcite, quartz, amphibole, ami other

minerals. The ore bodies consist of

d tliose parts of this mineralized zone

g which carry copper values wilh some

£ gold.

. andC. W., TheKflchlLiil and WranRf" mlnluR illilrlcis: Hull. I". S. Iltful. Survey lSt-l2S. , and KDopt, Adolph, Mlnpra! resourr ol Ihr SahMnn-Whtli' Ulvpr .liMrl.'I. Alaska: Survfj No. 417, 1911), pp. .'W-M. , uid KbU, F. J., The lUamim and Clatli laWrs region: Dull. U. S, tJeol. Survey No. HO,

Geologic Features Of Metalliferous Lodes. 79

These Iliamna deposits, so far as the meager information about them permits comparison, bear a close analogy to the betterdeveloped lodes of Prince of Wales Island. While the intrusive is of a more basic character and more highly altered, the contact zone and the ores are very similar. It should be noted that the mineralized zone and the two wall rocks lie within a great stock of intrusive granite, probably of Mesozoic age.

Deposits Associated With Intrusive Rocks But Not In The

Zone Of Igneous Metamorphism.

Some of the copper deposits of the Ketchikan district in southeastern Alaska lie within the zone affected by intrusive rocks but not within the areas of igneous metamorphism.* These deposits occur in association with greenstone schists, chloritic schists, and sericite schists, and with argillites and other sedimentary rocks. The greenstone and cliloritic schists are probably chiefly altered igneous rocks. Some of them are known to be sheared intrusives. In most localities where the deposits occur intrusive rocks are known to be near at hand, and these are believed to be of Mesozoic age.

These copper-bearing lodes, so far as determined, occur along zones of fracture and usually have lenticular form. In some localities the ores appear to have been deposited in open spaces; in others the ore bodies consist of masses of country rock which have been impregnated by the mineral-bearing solution. No evidence has been seen of replacement of the country rock such as has been noted by Grant and Higgins in the deposits on Prince WilHam Sound. (See p. 81.) The mineralized zone may include one or more ore shoots in the form of bands, veins, or lenses, and these are usually separated from both walls by the impregnated rock carrying lesser values. These deposits are valuable chiefly for their chalcopyrite. They also cany pyrite, pyrrhotite, in some places magnetite, and a little hematite and galena, with a gangue of quartz and calcite, as well as the minerals of the country rock. Among the localities where such deposits are found are Skowl Arm and Niblack Anchorage, both on the east side of Prince of Wales Island. The deposits at the south end of Gravina Island are probably of the same general type.

Ore bodies also occur in the greenstone schists and quartzites which overlie the limestones of Copper Mountain (see PL V), a mile or two from intrusive granite. These include both fissure-vein and shear-zone deposits. The ores contain pyrite and chalcopyrite, with a small amount of sphalerite.

Wright, F. E. and C. W., The Ketchikan and Wrangell mining districts, Alaska: Bull. U. S. (twl. Survey No. 347, 1908, pp. 128-140. Brooks, A. II., Preliminary report on the Ketchikan mining district: Prof. Paper U. 8. GeoL Survey No. 1, 1902, pp. 74-96.

80 Mineral Resources Of Alaska, 1010.

In this group should also be included copper-bearing fissure veins occurring in limestone of the Kasaan Peninsula region. These veins carry chalcopyrite, galena, sphalerite, and tetrahedrite, with quartz, calcite, and barite as gangue minerals. In some places these deposits lie along the margins of intrusive dikes..

Deposits Disseminated In Intrusive Rocks.

Copper ores occur as disseminated deposits in the intrusive rocks of the Kasaan Peninsula region. The only commercial ore body of this type which has been developed is that of the Goodro mine, near the upper end of Kasaan Bay. This occurrence has been recently described by Knopfs as "a heavy green dioritic rock containing much biotite and, as the main copper-bearing mineral, scattered particles of bomite, with which are associated sporadic blebs of chalcocite and chalcopyrite." The ore body has been opened to a depth of 94 feet, where the copper content is said to be 2 per cent higher than at the surface. Knopf points out that this may be due to the greater prevalence of chalcocite on the lower level.

Deposits Associated With Ancient Volcanic Rocks And Sediments.

The fourth group of copper deposits comprises those which are associated with greenstones (altered volcanic rocks) and sediments of various types. Tliese deposits, so far as known, have no direct relation to igneous intrusive rocks, but it is possible that in the deposits of the Prince William Sound type belonging to this group there may be a connection between the genesis of the ores and certain basic intrusive rocks. Of a different type, though belonging to this same general group), are deposits of the Chitina region which occur chiefly in limestones and are not connected with any intrusive rocks. Wliile definite proof is lacking, it seems probable that the copper of both the Prince William wSound and the Chitina deposits was derived from copper minerals disseminated in the associated ancient volcanic rocks.

Copper-Bearing Lodes In Greenstones And Argillites.

The best-known examples of the de])osits in greenstones and argilUtes are those occurring in the Orca group of Prince WilUam Sound and adjacent regions. The following is abstracted from a report by Grant and Iliggins. The copper-bearing lodes occur along zones of fracture, in most of which shearing has taken

I Wright, C. W., Mining in soatheaslem Alaska: Bull. U. S. Gool. Suncy No. 370, 19(>9, p. 78. Knopf, Adolph, Mining in southeastern Alaska: Hull. U. 8. (lool. No. AV2, 1010. p. Ml. 3 Grant, U. 8., and Hlggins, D. F., Heconnaissanw of the tjeoloy and mineral resourceii of I'riuoe William Sound, Alaska: BulL U. S. QeoU Survey No. 443, lUlU, pp. 53-7L

Geologic Features Op Metalliferous Lodes. 81

place. These zones are mainly in greenstones that are altered basic lava flows and tuffs, with some intrusive rocks. Some of the mineralized shear zones occur in slates and graywackes and some along the contacts of the sediments and the greenstones. The shear zones strike parallel to the major structures of the region, with usually a steep dip. In some places the deformations have resulted in fracturing rather than shearing. So far as can be determined from the evidence in hand, the movements did not, as a rule, produce any notable open spaces, but there are exceptions to this, for at some localities fissure veins have been observed. Mineral deposition in the shear zones in part followed the open spaces thus formed and in part impregnated the country rock or replaced it where no notable open spacing occurred. Development has not proceeded far enough to admit of precise statement as to the shape of the ore bodies, but some of them at least appear to have a lenticular form, outlined by planes of movement. Some of the ore bodies have no well-defined walls. In many of the deposits there is an ore shoot, made up of more or less solid layers of metallic sulphide within the mineralized zone. These ore shoots vary more in dimensions from place to place than the deposits as a whole. Chalcopyrite is the most abundant of the ihetallic minerals and is usually associated with pyrrhotite. The proportion of these minerals varies greatly in a single ore body. Pyiite.also occurs but is much less abundant. Among the rarer metallic minerals are galena, bomite, sphalerite, and magnetite. The chief gangue minerals are quartz, calcite, epidote, and chlorite. The ores that have been shipped from this district carried considerable silver but only a small amount of gold.

The best-developed ore bodies of the district are those of the Ellamar and Beatson-Bonanza mines. At the Ellamar the lode consists of a lens-shaped ore body, whose greatest horizontal dimension is 190 by 80 feet, occurring in a slate-gray wacke series. The mine workings extend to a depth of 600 feet. The ore body consists of chalcopyrite, pyrite, and pyrrhotite, with some included masses of country rock. At the Beatson-Bonanza the ore occurs in a zone of hard greenish flinty rock which, for want of a better name, can be designated a homfels, though its sedimentary origin has not been proved. This homfels, which forms the country rock at the mine, occurs in a belt of slates and graywackes. The ore, which is cliiefly chalcopyrite, occurs in fractures and as replacements in the hornfels. It is found disseminated in the hornfels and also as bands of nearly pure sulphides (chalcopyrite, pyrite, and pyrrhotite), which are in general parallel to the bedding of the slates and graywackes. Some

1 Formerly called the Bonansa, but not to be confused with the mine of that name in the Chitina region.

983190— BuU. 480—11 6

82 Mineral Resources Op Aiaska, 110.

faulting has taken since the ore was deposited. Some basic dikes are present.

Ainonp; the deposits differing: from those described above may bo mentioned one occurring on Knight Island and near Mummy Bay, in which a coarse-<]:rained diabase has been heavily charged with pyrrhotito and elialcopyrite. Another type, which is found on Orca Bay, is made up of epidotized stringers which occur in a crushed amygdaloidal basalt. These stringers carry native copper, chalcopyrite, bornite, and chalcocite in a ganguo of quartz and epidote. In a few localities there are some well-defined fissure veins filled with quartz, pyi-rhotito, pyrito, and chalcopyrite.

Wliilo tliese deposits have not been traced to the mineralizing influent'c of igneous rocks, yet Grant and Higgins have pointed out that certain basic intnisives are later than the shear zones and that the ores may bear a genetic relation to these rocks. Copper-bearing lodes of similar geologic occurrence have been found in the eastern part of Kenai Peninsula.

COPPER-BEARINQ LODES IN AJSSOCIATION WTTH OREENSTOHES AVD LIlfXSTOHZS.

The copper deposits wliich stretch along the southern flank of the Wrangell Moimtains, in the Kotsina-Chitina district, have been investigated by a number of geologists,- but most of the following account is based on the observations and deductions of MofRt. With rard to coi)|)er resources, two formations of this field arc of first importance. The older com|)rises a gi'eat sequence of ancient ])jisaltic lavas, some of whicli are amygduloitlal, with wliich some sedimentary beds are mtercalated. TJiis scries aggregates at least 3,000 to 4,000 feet in thickness and is called the .Nikolai greenstone. This is conformably overlain by the Chilistone limestone, of Triassic age, made up of heavily bedded bluish-gray liinestone aggregating 3,000 to 4,000 feet m thickness. The contact between these two formations forms the locus of the most oi-e bodies wliich have yet been developed (see niaj), ]1. VI), but some occui-s throughout the greenstone and co[)|)er lodes have been found in the a long distance from the contact. The largest ore bodies so far found are those occurring within the liinestone and within a thousand feet of the gi-eenstone contact.

The conditions favorable to the disposition of a|)pear to have been determined chiellv the readiness with which the mineralbearing solutions could circulate. Therefore tlu openings developed

J CJranf , V. S., aii'l Iliiruins, I"). F., Prcliiniimry n-port on tho mineral resources of the sonthcm part of Kenai Peninsuln: linll. V . S. Siirvry No. 44J, HMD, pp. liJ*V-17S.

2Sclirador, F. C, cuul A. C. (Zoology and mineral revourfcs of a portion of the Copper River. district. aspr-iial public-ation of the I'. S. (JodI, Survey, 1!07. Mollit. F. II.. and M-vldren, A. Q., Mineral resources of tlie Kot-ina-Chitinn rccion. Al;L-ka: Ruil. V. S. CoiA. .urvcy No. .Tl. ll09. Moffit, F. II., and Capjv. S. R., '.oology and nuncral resources of the Nizina dij'tricl, Alaska: Bull. U. S. Geot Survey No. 44&, 1911.

OEOIiOGIG PEATTJBES OP METALLIFEROUS LODES. 83

by faulting, jointing, and shearing, which gave opportunity for this circulation, constituted one of the prime requisites to the formation of ore bodies. The most promising deposits have been found along lines of movement which intersected the contact at different angles. It also appears that the plane of the contact between the two formations locally furnished passages for the solutions, even where no movement had taken place.

A few deposits which can be classed as fissure veins have been found, but most of them are more or less irrularly distributed and represent replacements of the country rock by materials brought in solution along openings, many of which were very minute, caused by deformation.

Most of the sulphide copper deposits within the greenstone thus far prospected consist of irregular masses and blebs of the ore, distributed along zones of fracture, and in many places do not appear to have well-defined walls. Bomite and chalcopyrite are the most common of the copper ores in the greenstone, but some promising chalcocite ore bodies have been foimd. The copper deposits within the greenstones usually include very little gangue. Some vein deposits have also been found in the greenstone, and their ores are also chiefly bomite and chalcopyrite with a gangue consisting mainly of calcite, with some quartz and usually epidote.

Moffit regards the native copper deposits that have been found in the greenstone of the Kotsina-Cliitina belt as probably secondary and due to the reduction of sulphides or oxides. The most common types of these deposits are those in which grains and irregular and tabular masses of native copper are distributed through certain zones in the greenstones. These are most common in the amygdaloidal phases of tlie greenstone, and here many of the amgydules are filled with native copper. At several localities carbonaceous matter and copper oxide occur with these native copper deposits. Some of the alluvium carries a large amount of })lacer wliich appears to have been derived from deposits of tliis type. Much of tliis placer copper is in thin sheets as if derived from planes of jointing or foliation. Nuggets of placer copper weighing several hundred pounds are not unconmion, and one mass of native copper found on Nugget Creek weighed 2 or 3 tons.

The most important feature of the deposits in the limestone are summarized by Moffit and Capps as follows :

Copper deposits in limestone were formed by replacement of the limestone as a whole by copper minerals in solutions circulating along fracture planes such as faults, shear zones, or joints. The copper minerals are chalcocite and bomite, accompanied by malachite, azniite, and in places covellite as alteration products. As a rule, the

1 Moffit, F. H., and Capps, 8. R., Gology and mineral resouioes of the Nizina district, Alaska: Bull. U. S. GtoL Bamj No. 448, 1911, p. 79.

Mineral Besodrces Of Aia8Ka, 1910.

boundary between ore and country rock is diatinct, although the form of the ore body itflelf may bo very irregular. This is particularly tnie where tbo copper mineral is chaloocite. In depoeilB of bomito in limeatono a dissomi nation oE the copper minenl through the adjacent country roi-k wan noticed, and in aurh examples there is a gradation from ore to rmmtry rock similar to that in the greonfllono deporits. One of the best eiamplea of this kind ahowB a lar'o proportion o£ chali'ocile associated with the boruite, and tho deposition of the copper was accompanied by a thorough silicili cation of the limestone, liarge masMB of chalcocite like that of the Bon&nKa property are distinctly replacement depottils in fracture zones. No fragments of limestone are included in tho body of the ore, although imlated masses of chalcocit are scattered through the limestuno. Tho ores are moat frequent near the limeetoneroeustone yet some of them must ho fully 1,000 feet above the base of the limestone. It isa notable fact that azurite is far more common aaa socondaiy oxidation product in

FlOUHE 12 — CfolOjrtO'il.l

tile limestono replaccnioiii deiKKjim ihan niala<'hitu and Ihut it is deposilsingretmBlouc. Small veins of a/.nrilowilh corps of chalcoi'ilc show distinctly that tlie aKuritc in tho lloiiMii/.a miiii wiia by tho altoraticiii of chalcocite. Covcllitu original'd in a wniilar manner.

The Nikolai co|)pcr property, located on a trilmtan- of McCarty Creek, alfortls an example of tlic vein type of deposit in tlio greenstone. It lies in a fiiiilt zone whicli intersects and iiffset- tlic limestone-greenstone contact. (Seo fig. 12.) Tlie vein lias been traced horizontally within about 400 feet of tliis faulted contnct, though its nearest point to the hniestone ia only abont 50 feet distant. AcronHtifi to Mof&t the deposit is in part ii replacement of tlie greenstone, in pari a filling of a preexisting fissure. Chalcopyrite is the principal copper

Qeolooic Features Of Uetalufeboub Lodes. 85

mineral, but with it is considerable bornite. With these are associated calcite, epidote, and quartz as gangue minerals.

At the Bonanza mine is the largest and be9t-<leveloped ore body of tlic district. The mine is located at an altitude of about 6,000 feet,

Richoraonsurfac

LIm

.loo.

f f

w

V/

7 //

'/m

//

(eoOOFT.t)

0 lOO

Contour interva

10 feet

near crest of the ridge wliich separates tlie drainage of upper Kennicott River from McOarty Creek. The deposit inchitles bodies of chalcodte, which occur in a zone of fracture traversing the lime-

86 Minerai-. Resources Of Alaska, 1916.

stone and trending northeastward, in wliich direction it has been traced for about 1 i miles. The Umestone-greenstone contact, which is about 40 feet from the nearest point on the ore body, is not offset by the fault but has been subjected to some minor displacements. (See fig. 13.) The zone of fracture has been affected by more than one Une of movement. In the sheeted zone formed by this faulting, wliicli is from 50 to 00 feet wnde, occur the copper deposits, which range from small, irregularly distributed masses of copper to large, well-defined veins. The deposit appears to end above the limestonegreenstone contact, but a little mineralization is observable in the greenstone.

The ore is chalcocite, and but Uttle else is included in the deposit. Azurite has been formed as an oxidation product, and some covellite is also present.

It is a significant fact that promising deposits of similar character occur on the extension of this zone of fracture on the McCarty Creek side of the divide and have been prospected. There appears, however, to be a barren area along the fracture zone between the Bonanza and the deposits on McCarty Creek, but even here copper-bearing minerals are found in places.

No other copper deposits have been developed in Alaska wliich are similar in association to those of tlie Kotsina-Chitina region. There are, to he sure, copper lodes in limestone and in greenstone in (HiTerent parts of the Territory, but in none of these are the conditions of occurrence exactly similar to these described above. Some of the copper deposits of the White and Nabesna River regions occur in limestone, but these are for the most part in the contact zones of intrusive rocks and have already been described. There are also some deposits in the ancient volcanic rocks of this northern field which may prove to be similar to tliose in the greenstone of the Chitina Valley. On the whole, howoyor, the (posits of the two copper belts on the north and south of the Mountains appear to be dissimilar in occurrence and genesis.

Copper-Hearino Amvgdaloids.

Primary native copper lias been found by Moflit and Knopf in the upper White Kiver basin and constitutes the occurrence of tliis kind known in Alaska. The property containing this deposit, called the Copper King claim, is located at the head of the Middle Fork of White River. The country rock is a series of basaltic flows, breccias, and tuffs of Carboniferous age. To quote from Moflit and Knopfs report :

Native is apparently limited in its occurrence to a (Hirtain detinite volcanic sheet — a reddish lava that is locally amygdaloidal tx) a high degree. For 200 feet

1 Moffit, F. n., and Knopf, Adolph, Mineral resources of the Nabesna-White Kiver district, Alaska: Bull. U. S. Geol. Survey No. 417, 1910, p. M. Idem, pp. 5&-56.

Geologic Features Of Metalliferous Lodes. 87

along the outcrop of this sheet metallic copper iutergrown with prehnite, calcite, and zeolites can be found here and there in encouraging amounts. The cupriferous portion of the amygdaloid appears to be about 6 feet thiok, but as almost no development work has been done on the [1908], figures of this kind have little value. The copper occurs as irregular reticulating masses of metal several inches long and as small lumps and minute particles embedded in the minerals that fill or line the former vehicles in the lava flow. In places these minerals either ramify in small veinlets through the body of the rock surrounding the araygdules or form irregular masses, and such places are eminently favorable for metallic copper.

These deposits are considered primary in the sense that the copper was deposited in the amygdaloidal or native 'state and is not the result of oxidation of sulphides, as is believed to be the case in the copper-bearing amygdaloid of the Nikolai greenstone.

Silveb, Lead, Aistd Zinc.

Practically all the gold deposits and many of the copper deposits carry more or less silver. Galena, as has been shown, is not uncommon as an accessory mineral in these deposits. There are also some lodes in Alaska wliich are regarded . as valuable because of their silver and lead contents. These nearly always cany also some subordinate gold values. Argentiferous galena-bearing fissure veins have been developed on the south arm of Cholmondeley Sound — an indentation on the east side of Prince of Wales Island, in the Ketchikan district. These veins cut across both schists and limestone. According to the Wrights, where they crosscut the limestones they are replacement deposits. These veins carry galena, with a small amount of chalcopyrite and sphalerite, in a gangue of quartz, siderite, and calcite. Another group of galena deposits occurs about 12 miles east of Wrangell, in southeastern Alaska. Here there is a slate-schist belt about a mile wide lying between granite areas. These altered sediments are traversed by acidic porphyry and aplite dikes, and in these or along the contacts the galena deposits occur. The deposits are fissure veins, which appear to be persistent. They are heavily mineralized with galena, s])haleritc, and chalcopyrite.

Some galena deposits ' have also been opened on Coronation Island, which hes near the entrance to Chatham Strait, in southeastern Alaska. The bedrock of the island, so far as known, consists of Paleozoic limestones and schists, which have been intruded by granite. The ore deposits are irregular masses within a limestone country rock. Besides the galena, tetrahedrite and spiialerite are present in the ores.

Among the many locaUties where galena ore deposits have found in Alaska, that in the Fish River basin, in the eastern part

Wright, P. E. and C. W., The Ketchikan and WrangeU mining districts, Alaska: IJull. V. S. (leol. Smrey No. 347, 1906, pp. 187-188.

Idem, pp. 188-19a

Ucm, pp. 190-101.

88 Mineral Resources Of Alaska, 1910.

of Seward Peninsula, deserves mention. One of the first attempts at lode mining in Alaska was at tliis locality, at the Omilak mine, in 1882. According to Smith and Eakin,* the country rock consists of crystalhne limestone and schists and also some more or less schistose igneous rocks which are classed as greenstones. The galena ores occur in a zone of fracture in the Umestones, near the contact with some of the schistose greenstones. Within this zone they are irregularly distributed in masses and blobs. The galena carries gold and a large amount of silver.

Some galena deposits have also been found in the western part of Seward Peninsula, in the Lost River and Brooks Mountain regions.' These occur in shattered zones which traverse Umestones of early Paleozoic age. Some of them are clearly contact -metamorphic deposits of granite and limestone; others are more or less intimately associated with quartz porphyry dikes.

No deposits valuable for their zinc contents have been found in Alaska. As has been noted in the preceding pages, sphalerite is a common accessory mineral in the gold, silver, and some of the copper deposits.

Tin And Tungsten.

Cassiterite in the fonn of stream tin is not an uncommon mineral in the auriferous gravels of the Yukon-Tanana region and Seward Peninsuhi, but its only knoAvn occurroncos of possible commercial vahie are Hniited to the York re<]non, in western part of Seward Peninsula. Stream tin, however, forms a eoiLsiderable percentage of the concentrates from the shiicing operations on some of the placer mines on tributaries of Patterson Creek, in the Hot Springs district, of the Tanana Valley. Considerable stream tin, associated with wolframite, has also been found on Deadwood Creek, in the Birch Creek district. Scheelite, another mineral, luus been found both in some of the auriferous <:ravels and in some small quartz veins on Seward Peninsula.

The only lode-tin deposits of wliicli there is (finite knowledge are those found in the western part of Sewaid Peninsula. Contributions to the knowledge of these lode and placer tin (lo|)osits have been made by several o:eolot!risks, but the following; statements are

1 Smith, P. S., and Eakin, U. M., A pt'ologlo n'oonnuissiina' in .wuthoastprn Srwanl IVnlrusula and the Norton Bay-Nulato region: Bull. I'. S, (Jool. Survey No. 419, I'Jll, pp. l.SO i:.

Knopf, Adolph, The niinenil deposits of Iho Lost Kiver and Brooks Mountain regions of Seward Peninsula: JUill. U. S. Geol. Survey No. 345, 1908. pp. 2(>S 271.

Johnson, B. L., Oocurrence of wolframite and cassiterite in the oM placers of Birch Creek district: Bull. U. S. (Jeol. Survey No. 442. IIMO, pp. 24fV-2:)().

Biooks, A. H., new occurrence ol cassiterite in Alaska: S<'ience. new ser., v()l. l.T No. .32s. p. 593: A reconnaissance of the Cape Nome and adja<*ent gold fields of the Seward i'eninsula, Alaska. 19<)(), a special publication of the U. S. Geol. Survey, 1901, pp. 132-i;9. Collier, A. J., A reconnaissance of the northwestern part of Seward Penin.sula, Alaska: Prof. Paper U. S. (Jeol. Survey No. 2. p. 49; Tin drpo-lts of the York rojdon, Alaslca: Bull. U. S. Geol. Survey No. 229, 1904. Iles. F. L.. The York tinTeglon: Bull. U. 8. Geol. Survey No. 284, 190('), pp. 145-157. Knopf, Adolph, Geology of the Seward Peninsula Ud deposits: Bull. U. S. Geol. Survey No. 358 1908.

Geologic Features Of Metalliferous Lodes. 89

based almost entirely on the report of Knopf, who has made s more exhaustive study of this field than anyone else.

The York region, as here defined, comprises an area about 50 miles in width, including the weat end of Seward Peninsula. A series of more or less altered argillitic slates, which contain much arenaceous material, comprise the oldest rocks of the field. (See

? f

W-

.— Owloglc sketch m

fig. 14.) These appear to be overlain on the east by heav' limestones of early Paleozoic age. On the west they are faulted against some crystalline limestones and schists, which are of Carboniferous age. Greenstones occur in the slates, and granites and quartz porphyry dikes cut all the formation. Kn<)pf ' summarizes

Mineral Besoubces Of Alaska, 1010.

the different types of cassiterite-bearing lodes, ivliich in the alates are genetically related to intrusive granites, as follows:

1. In a tourmaline-axiiiite homfelfl.

2. In beds of actinolite rock which are probably intantxmtilled with dalM.

3. In tourmalinized margins of granite maasea and granitic diksa.

4. In mineralized quartz porphyry dikes.

5. In quartz veins cutting granite and accompanied by impngnation of the adjoining granite.

6. In quartz stringers cutting slates and limestones.

These deposits carry a laie number of mineral species, which it b not worth while to enumerate here. Among the tungsten minerals wolframite and scheelite are worthy of note.

The cassiterite and wolframite of the alluvium in Deadwood Creek have been traced by Johnson to a granite- contact zone, and prospectors report a small vein carrying these minerals in the vicinity. Johnson has listed the following minerals as occurring in the concentrates from this alluvium: Wolframite, cassiterite, magnetite, ilmeiiitc, arsenopyrite, pyrite, galena, limonite, garnet, tourmaline, and quartz. The other creeks in the Yukon-Tanana region diich have yielded stream tin all lie in areas of granite intrusions.

Iron.

In the absence of any development of the coking coals and the lack of transportation, tlioro lias been little encouragement to prospect Alaska's iron ores. Therefore there are few data on which to base conclusions regarding their geologic occurrence. Tlu'ee types of ironore deposits have been recognized — (1) iron ores lying in the zones of igneous mctamorphisni, duo to intrusion and to be classed as contact ores; (2) vein deposits; (3) deposits of magmatic segregations. The occurrence of 'magnetite in the contact zones of limestones and other sediments and intrusive rocks has already been noted in the description of the copper deposits with which these iron ores are associated (pp. 74-79). The best known of this type of magnetite deposits are those of Prince of Wales Island. Of these occurrences the Wrights* say:

At the copper mines in Kasaan Peninsula magnciito forms about half of the ore masB and occurs in large amounts in some of tJie in the vicinity of Hotta Inlet. At several places on Prince of Wales Island mafrnetite occurs in masses sufficiently high in grade to make an iron ore, though no attempt has been made to mine it as such.

No analyses areavailable of these magnetite ores, but similar types of deposits have been mined on Tuxedo Island, in British Columbia,

1 Johnson, B. L., OocuiTCTtce of wolframite and cassiterite In the gold placers of Deadwood Creek, Bindl Creek district: Bull. U. S. Geol. Survey No. 442, 1910, pp.

Wright, F. E. and C. W., The Ketchikan and WrangeU mining districts, Alaska: UuU. U. 8. QcoL Smvey No. 347, 1906, p. 89.

feaTxjmjs of metalufekous lodes. $1

and these have an average of 55 to 60 per cent of metallic iron,' while the phosphorus content of most of them is low enough to make them fall within the Bessemer limit. The sulphur content, however, is high. Magnetite occurs in similar geologic association on Prince WilUam Sbimd, in the Iliamna region, and in the Nabesna region, as well as elsewhere in Alaska.

So far few examples of the vein type of iron deposits have been found. Schrader described a magnetite ore body which appears to be a vein in the Nabesna region. This vein is well defined and occurs at a contact between limestone and diabase. Grant and Higgins report the occurrence of hematite and magnetite bearing veins in the Prince William Sound region.

Iron-ore deposits of the segregated type occur near Haines, in southeastern Alaska, but their commercial value remains to be established. These, according to Kjiopf ,' consist of primary magnetite disseminated in a basic rock composed of pyroxene and hornblende. The best specimens seen carried a maximum of 30 per cent of magnetite. A microscopic examination showed the presence of apatite and the analysis of one sample showed 3.91 per cent of TiOj.

Chromite occurs near Port Chatham, on Kenai Peninsula.* The country rock is a peridotite, composed essentially of olivine, which contains small grains of chromite In places the chromite is abundant and is segregated in small bands, and these form the ore deposits.

Anthcony.

Stibnite, the sulphide of antimony, is one of the most widely distributed ores in Alaska. As has been noted, it occurs as an accessory mineral in many of the ore bodies of types already described. It remains to give an account of the occurrence of stibnite-bearing lodes in which the stibnite is the dominating metallic mineral. In all these occurrences the stibnite-bearing lodes carry more or less gold, and a number of them probably carry enough gold to warrant classifying them with the aiuiferous lodes.

In southeastern Alaska stibnite has been recognized only as an accessory mineral in some of the gold ores. Grant and Iliggins have described an occurrence of stibnite on Port Wells, Prince WilUam Sound. At this locaUty there is a zone of brecciation along a fault

Lindeman, Eimar, Iron-ore deposits of Vancouver and Tuxedo Islands, British Columbia: Pub. No. 47, Canada Dept. Mines, Mines Branch, Ottawa, 1910.

s Mendenhall, W. C, and Schrader, F. C, Mineral resources of the Mount Wrangell district, Alaska: Prof. Paper U. B. OeoL Sunrey No. Ifi, 1903, pp. 65-m.

s Knopf, Adolph, The ooconenoe of iron ore near Haines: Bull. U. S. Geol. Survey No. 442. 1910, pp. 144-14A.

Grant, U. B., and HIgginSr D. F., Preliminary report on the mineral resources of Kenai Peninsula: BnlL U. 8. OeoL Smrey No. 442, 1910, pp. 1G8-160.

Grant, U. and HIggtns, D F., Reconnaissance of the geology and mineral resources of Prince WilUam BulL U. 8. Geol. Survey No. 443, 1910, p. 78.

92 Mineral Resources Of Alaska, 1910.

line which cuts across tho country rock of black slate and graywacke. Tliesc sediments are cut by acidic dikes in the vicinity. The stibnite ore occurs in a band of vein quartz along the hanging wall of the shear zone. No other minerals were noted in this deposit. Grant and Iliggins also report the occurrence, near Kenai Lake, north <rf Seward, of a line-grained sheared acidic dike which contained particles and stringers of stibnite. Of the stibnite in the Fairbanks district Prindle says:

Stibnite was common in the concentrates from the placers in the early da3r8 of mining in the F'airbanks district and was afterw'ard found in place in the bedrock at sevenl localities in widely different parts of the district. It occurs in place here and there in the drainage area of Cleary Crtek, and, together with arsenopyrite, accompanies the gold in the richest of the quartz veins. It has been found as narrow stringers composed almost entirely of mas.'iTC stibnite crosscutting quartzite schist or forming a net workof stibnite veins between fragments of brei'cia ted schist; in veinsof quartz and stibnite, where the massive stibnite occupies the spaces left between quartz crystals; and as fine needle-like crystals or small crystalline groups along with some fresh, clear quarts areas in more or less f ruct ured cjuartz veins. At one kxlity stibnite was found in close association with a sericitized dike of granite The schist had not only been intnided by the dike but had apparently been fractured by it. Stibnite has been depailf on the surface of the dike and o(.'curs as small veins and lenticular masses up to Hcveml pounds in weight in the schist. The stibnite at this locality is apparently in close genetic asscxiation with the granite por|)hyry.

A ledge carryincr stibnite ha*s also been found on Caribou Creek, in the KanlLshna district.-* Here the stibnite is intergroTi quartz in a vein lying to the foliation of the country rock, which is a hornblende schist. iViitiniony-bearing ledges are known to have been found on Seward Peninsula, in the Nome Kiver basin and on u|)per Fish River. On Nfanihi Creek, a tributary of Nome River, there Is a (|nartz through which stibnite is disseminated. The country rock is schist, but the vein occurs near a limestone-schist contact.* At the Omilak mine,'* m the Fish Kiver bjisin, stibnite occurs in a shattered zone in a limestone bedrock. This limestone, which forms a belt almost one-fourth of a mile wide, bounded on both sides bv schist, is cut an altered intrusive rock.

Other Metallic Minerals.

Nickel and cobalt deposits have been re|)orted by prospectors, but in no samples tested by the Survey were these mentals found in commercial quantities. A small amount of nickel and traces of cobalt were found by the analyses of some pyrrhotit(. ores from the Ketchi-

Grant, U. S. , and Higgins, D. F., Preliminary report on the niinemi reMJurcoH of the southern part of Kenai Peninsula: Bull. U. S. Oeol. Survey No. 442, 1*10, p. 17s.

Prindle, L. M., Auriferous quartz veins in the Fairbanks district: Hull. V. S. (mhiI. Survey No. 442, 1910, p. 221.

a IMndle, L. M., The Bonnifield Kantishna regions: Bull. V. S. deol. Survey No. 314. VMM. p. 219.

Moint, F. 11., The Nome region: Bull. U. S. (-eol. Survey No. 'M4, 1WI7, p. l.W.

Smith, P. S., and Eakin, H. M., A geolcic reeomiuLssanoe in southenstem Seward Peninsula and the Norton Bay-Nulato region: Bull. U. S. Ueol. Sur\'ey No. 449, 1911, pp. 64-131.

Geologic Featubes Of Metallifebous Lodes. 93

kan district.* Similar tests on pyrrhotite ores from Prince William Sound revealed neither cobalt or nickel.

No commercial bodies of molybdenite have been found. In the Juneau district this mineral is found in some of the auriferous deposits which occur in the dioritic rocks, notably at the Tj-eadwell mine. Molybdenite has also been found in quartz stringers which cut the sediments altered by igneous metamorphism adjacent to the Coast Range granite belt in the Ketchikan district. It has also been seen as an accessory mineral with the gold ores in other parts of Alaska.

A deposit of native bismuth on which a little development work has been done occurs on Charley Creek, tributary to Sinuk River, about 25 miles north of Nome. The bismuth occurs in two small quartz veins cutting a schist bedrock.

A cinnabar deposit was discovered near Kolmakof , on the Kuskokwim, many years ago and is a perennial source of attraction to prospectors. This deposit has not been studied by members of the Survey. Spurr, however, notes that these veins cut shales of Mesozoic age, which have been intruded by acidic dikes. Cinnabar is found as an accessory mineral in some of the auriferous gravels. This mineral is very abundant in the concentrates from placer mining on Daniels Creek, about 60 miles east of Nome. While the bedrock source of this cinnabar has not been found, it evidently lies close at hand in a contact zone of schist and limestone.

A few minute grains of platinum have been found in some of the Alaskan gold placers, but nowhere in sufficient quantity to be of commercial importance.

1 Wright, C. W., and F. E., The KetcbOmn and Wrangell mining districts, Alaska: Bull! U. S. GeoL Survey No. 347, 1906, p. 87.

'Sporr, J. E.,A reconnaissance in southwestern Alaska: Twentieth Ann. Kept. U. S. Geol. Survey, pt. 7, 1000, pp. 261-262.

Mining In Southeastern Alaska.

By Adolph En6ff.

Introduction.

Southeastern Alaska has long held the world's record for the production of low-grade gold ore, a position due in the past mainly to the output of the Treadwell group of mines on Douas Island. These mines are operating on a nmieralized dike of albite diorite — a type of ore body of which this is so far the only one exploited in the ron. On the mainland there exist behind tbe town of Juneau enormous bodies of low-grade ore, consisting of slate irregularly cut by auriferous quartz stringers. Mines have been operating on these ore deposits at a profit for a number of yean, and the mining and milling costs have even been brought below those existing at Treadwell; but because of the disadvantageous situation of the mines several miles from tidewater the ore bodies have never been exploited on a scale commensurate with their magnitude. Plans have been fomiulated for their extensive development, but the execution of these lare projects has necessarily been -slow. Construction, however, was actually started in the later part of 1910, and it now appears that several hundred additional stamps will be dropping in the Juneau reon in 1912. It is safe to say that, with this increase of milling capacity and the new developments contemplated or in progress at Douglas Island, Bemers Bay, and Chichagof the gold production of southetusteni Alaska will at least be doubled within a few years.

In contrast to this marked expansion of the old-mining industry the copper-mining industry shows a stationary condition, nor with the prevailing low price of the metal is there likely to be any greatly increased output of ore.

Marble continues to attract attention as one of the mineral resources of southeastern Alaska. Prospecting continues and claims are located at widely separated locaUties, as at Dall Island, on the west coast, and at Limestone Inlet, 25 miles south of Juneau, and the productive quarries are enlarging their capacity.

Mining In Southeastern Alaska.

Gold Mines And Prospects. Pbodtjction.

According to preliminary estimates, the production of gold for 1910 in southeastern Alaska was substantially the same as that for 1909, in round numbers $4,000,000. The following table gives the tonnage and value for a number of preceding years. It shows clearly the preponderant influence of the low-grade ores of the Juneau district on the average value per ton :

Production of gold ore in southeastern Alaska.

Year.

190S

Ore mined.

Gold.

SUi

Amount.

Value.

Amount.

Value.

Tons. 1,206.639 1,475,516 1,478,429

Ounces. 198,285

12,734.885 3.348.312 4.098.900

Ounces.

S14.653 14,290

Average

value per ton.

r2.28

Juneau And Bebnebs Bay Be6Ions.

Douglas Island.

The steadily increasing depth from which ore is extracted at the Treadwell group of mines has made advisable an enlargement of the hoisting capacity. In order to realize the economies of a central hoisting plant, it has been decided to make the shaft of the 700-foot claim the main hoisting shaft of the three mines that are grouped on the same lode — the Alaska-Treadwell, the 700-foot, and the Alaska- Mexican. A contract has been let for a balanced hoist capable of lifting 5,000 tons from a depth of 3,000 feet in 20 hours, the net load being 8 tons. A new gallows frame will be erected and new crushing machinery of heavier capacity installed. It is anticipated that the entire plant will be ready for operation by the fail of 1911.

The hydroelectric plant at the mouth of Sheep Creek, wliich is capable of generating 2,500 horsepower for about two-thirds of the year, and the transmission line to Treadwell were completed during the year. Work was started on a transmission line from Treadwell to Nugget Creek at Mendenliall Glacier, a distance of 12 miles, where it is proposed to build a dam, probably 125 feet liigh, which will have a storage capacity equivalent to approximately 5,000 horsepower for 90 days. When this project is completed, it will be possible to run the 300-etamp mill of the Alaska-Treadwell the entire year. At present it is shut down during the winter months on account of lack of water power.

98 Mtneral Resources Of Alaska, 1910.

prospect has boen developed by a drift tunnel 30 feet long and by stripping of the ledge along the outcrop for several hundred feet.

SITKA AND KETCHIKAN MININa DI8TRI0T8.

The only active gold mines in the Sitka district are the Chichagof Oocally known as De Grofl) and Golden Gate mines. They are situated at the head of Klag Bay, on the west coast of Chichagof Island, 50 miles north of Sitka. Both mines are operatmg on what is presumably the same lode and are extracting a comparatively high-grade ore. The De Grofl mine and mill are situated near sea level and the Golden Gate mine at 1,000 feet altitude, but the mill has been built at tidewater.

At the Do GrofT mine the present miUing plant, consisting essentially of two batteries of two S50-pound stamps each and an edgerunner mill of the Cliili type, proved to be inefficient and subject to vexatious delays, and in conse(|uence it was decided to erect a new 10-stamp mill with heavier stamps and standard equipment. The ore milled during the year came from the rich ore shoot developed by the raise from the adit level to the upper tunnel; this ore was found to have a greater strike length than wjis indicated by the earlier workings.

On the Ciolden Gate property the stamp mill and aerial tram were completed and the milling of the ore commenced. The mill has been built for 10 stamps, hut only 5 have been installed. The ore was mainly that which had accumulated on the dump during the early developnicnt of the mine and was rather medium or low was continued, and an ore shoot in value to those of the De GrofT mine was reported to have been encountered late in June.

In the Ketchikan district several nundred feet of tunnel were driven on the l,()()()-foot crosscut tunnel at the Lon-de-Van group, which is situated on the north shore of (george Inlet. This tuimel, which commences at the beach, is jirojected to undercut the ore body exposed at 900 feet above sea level.

Development continued on the Julia claim at Hollis until September, when the mine was shut down. Late in tlie a small forc of men was put to work on the (loldstreani property on Gravina Island, miles from Ketchikan, with a view to the prop erly. The main work done consisted of (hitting on tlu oO-foot level. It is proposed to conduct experimental treatment of the ore to find a process that will give an economic extraction of the values, which have hitherto proved not readily amenable to ordinary stamp-milhng practice.

Mining In Southeastbbn Alaska. 99

Copper Mines And Prospects.

Qenebal Statement.

During 1910 copper ore was shipped from four mines, three of which are situated on Kasaan Peninsula and one on Hetta Inlet. They are all on Prince of Wales Island, in the Ketchikan mining district.

The main productive properties, as is well known, are located upon contact-metamorphic ore bodies, which commonly occur at or near the contact of limestone with intrusive masses of dioritic rocks. The ore is confined to the Umestone and occurs in deposits of irregular shape and value. Many of the bodies are rich, consisting of masses of nearly soUd copper mineral. These are easily exploited and a considerable tonnage of high-grade ore is rapidly extracted. They are then found to be surrounded on all sides by barren gangue material consisting either of magnetite, or crystalUne limestone, or masses of lime silicates such as garnet, epidote, and pyroxene. The problem is then to find more ore. Inasmuch as the ore masses are without walls or other features that usually serve as guides in the search for new ore, the problem is difficult and no consistent or systematic method of development work has j'et been evolved. At two of the mines diamond drills have now been installed to expedite the exploration for more ore.

A fear seems to exist m tjie district that ore will not persist in depth. Exploration work has been mainly in the lateral directions at comparatively shallow depths. Deeper development has perhaps been retarded by the apprehension that the ore will not go down. This fear appears to the writer to be groundless. It should be borne in mind, however, that although the ore bodies are likely to persist downward their distribution within tlie ore-bearing zone will be as irregular and erratic in depth as it is in the upper levels. This is no peculiarity of the Alaskan deposits but is common to all ore bodies of contact-metamorphic origin. Inasmuch as the primary sulphide chalcopyrite — the only cupriferous mineral in tlie ore — outcrops at the surface and, furthermore, as the origin of the ore bodies is independent of any relation to the existing topography, there is no reason to anticipate that the ores on the average will become richer in depth.

These deductions follow purely from the geologic evidence. The record of actual producing mines affords welcome data as to the possibilities of this type of ore deposit at increasing depth. On Texada Island, British Columbia, ore bodies of contact-metamorphic origin persist to a depth of at least 1,000 feet and the values in copper, gold, and silver hold in the bottom levels. At the Jumbo mine, on Hetta Inlet, in the region under discussion, the vertical range throughout which bodies of ore are known to occur exceeds 700 feet.

lOKSRAL BBSOTTBOBB OF ATAflKA, VUk

On tlie whole it can be said that the pist record of the main producing mines on Prince of Wales Island shows that themaeseB of ore are encountered within the ore-bearing zone in suflScient number to maintain a profitable production; that this will contimie in depth seems probable enough to justify in some mines a mote systematic method of development than has yet been attempted. XSztremely long adit levels that aim to undercut the oie-beaiing aoneB at depths of more than several hundred feet, howeveTi are inadvisable, on account of the proved capricious character of contact-metamoirphic zones.

The production of copper ore in southeastern Alaska daring 1010| as shown by a preliminary estimate, is 2,250,000 pounds, which is less than that of 1909. The output for a number (rf preceding yeais is shown in the following table:

Production of copper ore in BoutheasUm AUtdbeu

Ymts.

Ore mined.

Copper.

Odd.

Bow.

Annm

Amount.

Value.

Amount.

VdM.

Totu, 79,982 28,491

Pounds.

4.758.814 3.2r.399 2,705.988

4.W..372 361,778

Ounces.

3,384

mo. 900

24. M8

13,088 8. Ml

BUb 14

190K

Ilio

Hikan Mining District.

Kasaan Peninsula.

The Mount Andrew mine, wliich is operating on a contactmetamorphic ore consisting essentially of chalcopyrite in a gangue of magnetite, maintained its usual annual production and in addition undertook some important new devclo])ment work. The main supply of ore was obtained from sto])es 2 and 4. Considerable drifting was done on the 50-foot level and good ore wius encountered at several places. A raise was put tlirough from this level to ore shoot No. 4, from wluch a large tonnage of rich ore has been extracted in the past and which is now being stepped downward from the main adit level, tunnel No. 1. A new tunnel, known as No. 2, was started several hundred feet northwest of No. 1, undercutting the outcrops at a depth of 100 feet, and enough ore was encountered to continue prospecting. The most noteworthy development work commenced during the year was that done on the new tunnel, designated No. 3, which, commencing at the old camp, is projected to undercut the ore body 300 feet below the present working level. The length will be 1,600 feet; 100 feet had been driven by the end of September.

Mining In Southeastern Alaska. 101

At the It mine operations for the year commenced early in April. The main ore bodies lie in an embayment Oi limestone in an intrusive mass of diorite. The limestone has been coarsely fecrystallized and more or less converted into lime-silicate rock: -The ore consists of chalcopyrite in a gangue of calcite ; the silicates,' consisting of garnet, epidote, pyroxene, and others, contain only a smalt amount of copper mineral irregularly scattered through them. Development is proceeding on three levels below the working tunnel, the lowest being at a depth of 150 feet. From these levels the surrounding i:er' ritory is being carefully prospected by diamond drilling.

At the Dean, a newly discovered prospect not far from the It mine, a tunnel 100 feet long was driven and a shallow winze was sunk 50 feet in from the portal. The ore is of contact-metamorphic type and consists of chalcopyrite in a gangue of coarsely crystalline pinkish calcite, associated with varying amounts of garnet, pyrite, and hematite. Several hundred feet northeast of this tunnel another has been driven approximately 75 feet long in a mass of lime-silicate rock.

Operations were resumed late in March at the Goodro mine after the winter shutdown. The main development undertaken consists of a winze sunk a depth of 100 feet below the tunnel. From the bottom of the winze drifts were driven both east and west and aggregate 150 feet in length. The winze is said to have been sunk in ore for 45 feet — that is, bomite in a heavy gangue composed essentially of pyroxene and biotite, with some feldspar and epidote. In the bottom level, which is 200 feet below the outcrop, some finely disseminated chalcocite and native copper were encountered. A width of 14 feet of this kind of ore is said to have been crosscut. All work was suspended after the middle of September, but it is planned that future exploration shall be done by diamond drilling. The discovery of chalcocite at a depth of 200 feet shows that the process of secondary sulphide enrichment has gone far deeper than would have been considered probable in this highly glaciated region. No such enrichment has affected the contact-metamorphic deposits, and this occurrence is therefore the more surprising.

Hetta Inlet.

The only property on Hetta Inlet productive during 1910 was the Jumbo mine of the Alaska Industrial Co. This mine is the largest producer of contact-metamorphic copper ore in Alaska. The ore is mainly derived from the upper levels, in which there still remains a laie amount of unexplored territory. In the stope on tunnel No. 4, the working tunnel and deepest level, a vertical diamond-drill hole was put down 130 feet and ore was encountered, that at tliis property the contact-metamorphic ore has a vertical range of at least 700

102 MINERAL RESOURCISS JDF AUkfiKA, 1910.

feet. On the level of tunnel-'-N:*! the ore-bearing zone is being explored southeastward by tllmolid drilling. A tunnel, projected to be 5,000 feet long and to lip'dercut the ore bodies at 1,500 feet depth, has been started from* tidt'water, but work on it is not being pressed.

At the Red Wing' inine it was reported that a crew of 12 men were employed" iftiflking a new shaft, planned to be 500 feet deep. This was the grill other mining activity of note on Hetta Inlet during the

OTHEB LOCAIilTIBS.

At Big Harbor, near Klawak, on the west coast of Prince of Wales Island, the Northland Develo])ment Co. is said to be prospecting an ore body 62 feet wide and has driven an aggregate of 400 feet of drifts and tunnels. The ore was to consist of chalcopyrite in a lime gangue, but the samples shown to the writer proved to be a highly siliceous sericitic schist carrjnng disseminated chalcopyrite and pyrite. Some ore rich in black zinc blende was seen that came from the same locaUty.

At Seal Bay, on Gravina Island, the main crosscut tunnel has now attained a length of 1,700 feet, but driving ahead has been suspended. Eight quartz-chalcopyrite veins are reported to have been crosscut; at present the vein known as No. 3 is being drifted on and shows 5 feet of ore nmning 2 cent in copper.

Late in the year a crew of six men was emplojed at the Rush & Brown mine, whicli is situated near the liead of Karta Bay, on Prince of Wales Island. The mine* was unwatered and ])reparations were made to get out a shipment of ore.

Development work continued at a number of other copper prospects scattered tliroughout the Ketcliikan district, such as the Yellowstone group, on Dall Island; the Vcta rouj), at Mallard Bay, near the south end of Prince of Wales Island, and others; but no operations of any considerable magnitude are to be recorded.

It is reported that work was resumed by a small force of men on the Moonshine vein, on the South Arm of Cholniondelcv Sound. The values in tliis property are silver and lead, and it is one of the few of its class in southeastern Alaska.

Tee Eagle River Region.

By Adolph Knopf.

Introduction.

The Eagle River region as defined in this report embraces the portion of the Juneau gold belt extending from Bemers Bay on the north to Salmon Creek on the south. A topographic map of this region on the scale of 1 mile to the inch was commenced by J. W. Bagley in 1909 and finished in May, 1910. The accomplishment of this work completed the detailed mapping of the northern portion of the Juneau gold belt, which contains all the important mines and most of the prospects under development. The Juneau and Berners Bay maps have already been issued, and the map of the intervening territory is now in course of preparation.

Detailed geologic examination of the region has succeeded the topographic mapping. Detailed reports are available on the geology and ore deposits of the Juneau and Bemers Bay regions. The present report, which is based on work done during parts of the field seasons of 1909 and 1910, aims to give in summary form the essential geologic features of the Eagle River region. A detailed report is now being prepared.

General. Geography.

The gold belt consists of a narrow strip of country lying between the high peaks of the Coast Range and salt water. The general trend is northwest and southeast; the length of the belt as measured from Salmon Creek, which is 3 miles northwest of Juneau, to Berners Bay, on the north, is 32 miles; the width ranges between 4 and 5 miles.

The region is one of abrupt topographic features which increase in ruggedness toward the northeast. Here the numerous glaciers and precipitous reUef make the mountains nearly inaccessible. The drainage of the region is mainly longitudmal, but the larger streams, like Eagle and Mendenhall rivers, which are of glacial origin, flow across the general trend of the belt.

Spenoer, A. C, The Juneau gold belt, Alaska: Bull. U. S. Geol. Survey No. 287, 1900. Knopf, Adolph Geology of the Berners Bay region, Alaska: Bull. U. S. Qeol. Survey No. 440, 19U.

104 MINERAL BE80UBCE8 OF AT.AgyA

Gastineau Channel and Lynn Canal bound the r;ioii on the southwest, so that it is easily accessible by water, but owing to the facts that there are few good harbors and that the mnuntainii rise directly from the coast, ingress to tiie interior of the belt is practicaUe at a few points only.

A well-built Government trail traverses the length of the belt and connects Amalga, on the head of Eagle Kiver, with Juneau. This trail renders the extreme inland portion of the gold belt somewhat more accessible than it has been in the past, but for the transporter tion of heavy freight from Juneau the waterway is far move servioeable. The economical development of any mining property in the belt necessitates the building of a tramway to the nearest harbor, and this is the course that has been adopted at those places where any operations of importance have been undertaken.

General Geology.

The rocks of the region are arranged in belts striking parallel to the general trend of the gold. belt. The dip is generally steep to the

northeast.

Quartz diorite gneiss forms the northeast boundary of the belt. This rocky which in local speech is accurately enou known as granite, consists essentially of plagioclase feldspar (near labradorite), quartz, biotite, and liornblende, all of which are discriminable by the unaided eye. The gncLssic structure, which is in part a primary structure but was produced mainly by the crusliing of the component minerals of tlie diorite, toward the northeast grades into the massive granular texture characteristic of normal granitic rocks. Viewed broadly this neissic belt, which is from 1 to 2 miles or more wide, forms the foUated margin of the quartz diorite core of the Coast Range.

A belt of schists adjoins the gneiss on the southwest. Its width ranges from 2 miles at Mendenhall Glacier to a few hundred feet at Berners Bay. The schists comprise a considerable variety of rocks, mainly of original sedimentary origin, and show a considerable diversity of mineralogic make-up. Biotite, garnet, and amphibole are the most common minerals of metamorphic origin that are easily distinguishable, and of these biotite Ls by far the most abundant and widespread. Coarsely crystalline wliite limestones are interstratified with the schists in small amount but are disproportionately conspicuous. Along the southeast side of Herbert Glacier a large volume of augit melaphyres is included in the schist belt. On glaciated surfaces the weather tinting shows that some of these rocks were originally conglomerates or breccias. The shapes of the fragments are well shown, and the fragments differ from one another

The Eagle River Region. 105

in that some are more thickly studded with augite phenocrysts than others.

The schists are in many places exceedingly contorted. They are most highly crystalline where they adjoin the diorite gneiss, but toward the southwest they grade imperceptibly into the clay slates and graywackes of the next belt of rocks. In fact the boundary between the schists and the slate-graywacke formation was arbitrarily fixed by determining the first appearance of visible flakes of biotite in the rocks as the diorite gneiss is approached.

At many places along the contact of the schists ana gneiss the schists are extensively injected with dioritic dikes. The dikes possess a gneissic structure and he parallel to the foliation and stratification of the schists; in places this interlayering is so thorough and the alterations induced so profound that it is impossible to tell what is diorite and what is schist.

South of Mendenhall Glacier the schists are intruded by numerous white granitic dikes of both coarse and fine grained varieties. Many of the dikes are contorted with the schists, but others cut across the folds.

The belt of slates and graywackes lying between the schists and the volcanic rocks (greenstones) paralleling the coast comprises the most important rocks in the region. Nearly all the ore deposits are located in it. This formation is typically displayed along the shores of Bemers Bay and has been named the Bemers formation. Fossil leaves were found at that locality and indicate that the rocks are of Jurassic or Lower Cretaceous age.

The general strike of the rocks is northwest and southeast and the dip is almost invariably northeast, ranging from 20° to vertical. Angles of to 60® are the most common. In places the rocks are acutely folded and the axes of the folds stand vertical, but no evidence of more extensive folding was procured. The cleavage in the rocks is generally parallel to their stratification, but discrepancies occur locally.

At Bemers Bay the graywackes are intimately interstratified with the slates. Toward the south they become less abundant and are comparatively scarce south of Eagle River. At Auke Bay the graywackes are practically absent and the rocks consist of fissile black slates. The strata of graywacke, so far as observed, range to a maximum thickness of 80 feet.

The graywackes are gray or greenish-gray rocks of roughly schistose or massive structure. They are composed largely of grains of plagioclase feldspar and quartz, together with fragments of other minerals and rocks, embedded in an aiUaceous cement. Except the glassy

1 Boll. U. 8. Qeol. Survey No. 446, 1911, p. 17.

106 MINEBAL BE80UBCE8 OV ALiJUKA, IfllA.

grains of quartz and the fragments of blade slate, none of these omstituents are recognizable by the eye. The fresh roek taken from mine openings is black, owing to the presenoe of finely disseminated carbonaceous material; that taken from the natunl ezposuies is gray or mottled gray, because bleached by the action of the sunlight. The graywackes are far harder rocks than the soft slates inteEstratified witii them.

With increase of argillaceous material in the graywackes the cleavage approaches in perfection tliat of the interbedded day slates. Such rocks might be called graywacke slates. On oioss-fractured surfaces some of them show only numerous gtening particles of quartz embedded in an aphanitic matrix.

Masses of volcanic rock form scattered areas throujKnit the belt of graywackes and slates. The most persistent developmeiit, however, is in the long belt fringing the coast from Bridget to Auke Bay. The volcanic rocks include lavas, flow bieociasy UsBb and coarse breccias, and conglomerates. Clay dates are intercalated with them at some places, and it is a general rule that beds of fragmental igneous rocks alternate with normal sedimentary rocks near the margins of areas of dominantly volcanic rocks.

The characteristic feature of these rocks is the widespread prevalence in them of numerous well-formed and well-preserved augito phenocrysts set in a dark blue-green matrix of aphanitic texture. Feldspars are notably absent. Pending more complete petrographic investigation these rocks will be designated augite melaphyres, according to the descriptive field classification of Pirsson. In places they are extremely amygdaloidal; between Yankee Cove and Bridget Cove they display a striking ellipsoidal structure. The conglomerates consist essentially of volcanic material; the pebbles range from well rounded to angular; the matrix is tuffaceous or of volcanic origin, so that it is in many places unpossible to discriminate conglomerates from breccias.

The bulk of the rocks show no scliistose structure. The strike is northwest and southeast; the dip ranges from 20° N. at Auke Bay to vertical at Bridget Cove.

A considerable number and variety of dikes, mainly greenstones according to local usage of the term, are intrusive into the slates and graywackes, but few exceptions all of them lie parallel to the stratification of the inclosing rocks. Dikelike masses of augite melaphyre, identical with the rock of the volcanic areas, are common, but whether they represent interbedded lava flows or intruded sills is determinable m few places. It is probable that both forms are present, but the distinction does not appear to be of practical importance. These sheets range from a few feet to 300 feet in thickness. They are hard massive rocks, but the contacts are, as a rule, thoroughly schistose.

The Eagle Biveb Begion. 107

Dikes of augite lamprophyre have a widespread distribution throughout the region, being found from Bemers Bay on the north to Douglas Island on the south. They resemble the augite melaphyres in some respects but consist essentially of large augite phenocrysts embedded in a finely granular gray-greenish matrix. In some of these dikes augite crystals form the bulk of the rock; in the betterpreserved specimens the augites are of fresh green vitreous appearance. Dikes up to 100 feet thick were noted.

Diorite porphyry dikes are found in the region south of Eagle River. Some of them, on account of their resistance to erosion, are unusually well exposed and form the beds of streams for several miles. These dikes are light-gray rocks consisting of white feldspar phenocrysts and scattered hornblende prisms set in a finely granular or dense groundmass. Some dikes of quartz diorite porphyry are found on the peninsula on the east side of Auke Bay.

A narrow belt of diorite 5 miles long extends south from Eagle River. This rock is of medium to fine grained granular texture and is composed of plagioclase feldspar, augite, and biotite. Thefeldspar is somewhat epidotized, and the rock tends to assume a green hue. This diorite differs considerably in appearance from the quartz diorite that occurs along the northeast maiin of the gold belt, nor does it possess a gneissic structure. It probably represents a separate intrusion like the Jualin diorite at Bemers Bay. A porphyritic diorite dike several himdred feet thick was traced for a distance of 7 miles southeastward from Eagle River along the hills flanking the east side of Peterson Creek. The rock carries numerous laie tabular feldspars, which impart to it an individuality that distinguishes it from other dikes in the region.

m

Economic Geology.

The ore bodies are exclusively gold deposits. The great majority are stringer lodes; a few are fissure veins, and a number of mineralized dikes have been discovered.

Nearly all the ore bodies occur within the belt of slates and graywackes ; a few are found in the quartz diorite gneiss ; none of economic importance are known to occur in the belt of schists. The marginal portion of the slate-graywacke belt that adjoins the scliists appears from present developments to be the longest zone of continuous mineralization in the district.

The ore bodies designated stringer lodes are belts of slaty or schistose rock cut by irregular quartz stringers. As a rule the ore bodies tend to follow the structure of the inclosing rocks, both in strike and in dip, but individual stringers commonly cut across the cleavage irregularly. Solid bodies of quartz are occasionally found and may apparently show the normal attributes of ordinary fissure

108 Mineral Bb80Ubcb8 Of Alaska, Iml

veiiis, but such masses of quartz are inyariably foimd to fray out into stringer lodes along boUi strike and dip.

Many of these ore bodies can hardly be said to po— onw definite walls. At some places, however, the better ore la found to occur in slate that rests upon a f ootwall of graywacke ; at other places minenlization has taken place in slate lying along s footwaU of aiigite melar phyre. In general terms, an intercalated sheet of hsxder and nune massive rock is likely to serve as footwall. Where this is so the melaphyre, which is usually referred to as greenstone, is mors Bkely to form a continuous wall than tlie graywacke, for the graywacke beds are inclined to have a short lenticular structure and to be discontinuous along strike and dip.

Except for sporadic shoots of rich ore, the stringer lodes are of low grade. They range in widtli from a few feet to 100 feet and " endy at a few prospects to 300 or 400 feet. Tbe greatest depth attained anywhere in Uie district does not reach 200 feet. The average value of a stringer lode is dependent upon the number and richness of the individual quartz stringers contained in the whde mass of slate. As a rule tlie quartz veinlets are leanly minaralised with sulphides, and tliese have a tendency to be mawwid in and around fragments of slate inclosed in the vein stuff. Anenopyrite is the commonest sulpiride, and pyrite, galena, pynhotitei and sphalerite are found in the order named, but as a rule all do not occur together in the same deposit. Free gold is rarely seen. Auriferous arsenopyrito running several dollars to the pound is found near Echo Cove, and the association of arsenopyrite and galena is everywhere accompanied by high values in gold.

The fissure veins differ from the stringer lodes in consisting essentially of narrow tabular masses of quartz. Only a few representatives of this class are known — not more than five — and all of them have tliis feature in common, that they cut across the stratification and cleavage of the inclosing rocks. One or both walls are generally marked by fault planes.

The mineralized dikes are few hi number and from present development appear to be of Uttle economic interest, but in the writer's opinion they are entitled to a somewhat more careful examination by the prospector than has been accorded to them. They were noted on the northwest side of Mendenhall Glacier and between Lemon and Salmon creeks, where. they are about 30 feet thick. The dikes are dioritic in composition and dark colored but where mineralized have been changed to a wliite rock, which is cut by numerous veinlets consisting of quartz, albite, and dolomite. The principal sulphide is pyrite; galena and arsenopTite are {)resent in minor amounts. Rutile occurs in sporadic largo crystals of adamantine luster but more commonly forms acicular aggregates in which the individual

The Eagle Biveb Region. 109

needles lie at angles of 60 to one another. The smaller veinlets through the rock consist largely of albite, and where the structure is drusy this mineral is crystallized in typical feldspar forms. This highly interesting kind of mineralization is essentially similar to that which has affected the Treadwell dikes, a few miles to the south; imfortunately this mineralization was not everywhere accompanied by auriferous deposition of commercial value.

Development.

The earliest operations in the region were those of placer miners on the heads of Montana and Windfall creeks in 1882. Old wing dams, ditches, and bowlder piles show where the pioneers labored, but because their efforts yielded a bare wage only, attempts at placer mining were soon abandoned. The first lode locations were made also in 1882 at Montana Basin and near Auke Lake. Prospecting has continued intermittently ever since. New discoveries are made from time to time and as late as 1908 extensive quartz croppings were uncovered near the point where the old trail crosses the summit between Auke Bay and Montana Creek. To those familiar with the ron such discoveries occasion no surprise. Outcrops throughout the inland portion of the gold belt below timber lino are effectually buried under several feet of glacial drift and this overburden is itself covered by a heavy growth of moss and vegetation. These features, together with the wet climate, render prospecting a difficult and onerous employment. It is therefore to be expected that occasional discoveries will continue to be made, aided as they have been in the past by the overturning and uprooting of trees and by the formation of landslides which from time to time bring to light new exposures of bedrock.

The state of development of the region in 1903 was described by Spencer and in 1905 by Wright. The development since that time has been far less rapid than was anticipated, and in view of the fact that a detailed report is in course of preparation, descriptions of individual properties are omitted in this preliminary account. Many causes have combined to retard the progress of the mining industry — litigation in some cases, inflated valuation in others — but principally the essentially low grade character of the ores. A large capital expenditiue is necessary to open the properties, and such investments usually demand a more adequate development of the ore bodies than has so far been made in most places. Even at Juneau, where the ore bodies have had the advantage of being near a center of population, the formulation and adoption of plans for the working of the low-grade gold deposits on a scale proportionate

BaU. U. 8. Oeol. Survey No. 287, 1906. pp. 117-134. BqIL U. 8. Qeol. Survey No. 284/1906, pp. 34-37.

110 MINERAL BE80UBGS8 OF ALASKA, IflML

to their magnitude has required many yean' timey'aad it is oo recently that these plans have been nearing aehierenuDft.

The production of the region, with the ezoeptioa of a few thonsani dollars, has been the output of a sinf mine at Bagle BiYor, whidi has been in operation since 1903.

FRACTICAIi CONCLUSIONS.

The foregoing sketch of the geology presents only those features having a bearing upon the occurrence of the ores in this regioiL Some inferences of a practical character have already been pointed out. The most striking fact in the geology of the is the almost complete restriction of the ore bodies to the belt of slates and graywackes. Although the ore bodies have been found distributed throughout the length and breadth of the area underlain by those rooks, they are nevertheless most numercnis in the ame lying along the belt of schists. Moreover, the hibesi-grade ore yet found in the region and the only productive mine are in that zone. The conclusion is therefore obvious that those portion of the belt adjoining the schists that have not been adeqniately prospected are the most favorable fields for further investigation, notably the stretch between Windfall Basin and Eagle Rivery and possibly that between Mendenhall Glacier and Montana Basin.

In other parts of the slate-aywacko area the contacts with the intercalatHl masses of augite melaphyre, and conglomerates (rocks that are coHeetively known in tlie region as greenstone) appear to fonn favorable localities for mineralization. Tte masses of harder rock are apt to their {)resence, at least in parts of the region, by fonning the bedrock of knobs or other topographic prominences.

A few small fissure veins have been found that break across the stnicture of the quartz diorite gneiss. The entire length of some of these veins is absolutely exposed on th<'' bare glaciated surfaces and does not reach 200 feet; the width is a few inches. Although some of these veins contain considerable free gold, they nevertheless show a surprising lack of alt-eration of their wall rocks such as generally accompanies productive ore deposits. In view of this unfavorable feature and the short, narrow character of the veins, extensive sinking of shafts on them is a waste of time and energy. Where larger and longer ore bodies are indicated and the (liorit<> is intensely altered by the action of vein-forming solutions, as on the flank of Mount Thane, further prospecting is to be encouraged.

The future of the district will, however, depend largely on the exploitation of the low-grade stringer lodes. The history of the mineral development of Silverbow Basin, at Jxmeau, will repeat

THE EAGLE RIVEB REGION. Ill

itself here. In early days attempts were made to mine some of the stronger veins found in the stringered zones of slate in Silverbow Basin, but owing to the nonpersistent character of these veins such attempts assured a precarious existence to the mines founded on them. By a natural evolution that is still goiug on methods have gradually been developed to mine and mill the whole mass of rock of the ore-bearing zone, and the practice has now settled down to exploiting ores ranging from $1.25 to $3 a ton in value. This is likely to be the coiue of development in the northern extension of the Jimeau gold belt.

The Upper Susitna And Chistochina Districts.'

By Fred II. Mofptt.

Introduction.

A topopntpliic reconnaiasanco aiin'-ey of that part of the south slope of the Alaska Rano and tho adjacent lowlands between the latitudes of Delta River and a point a few miles west of Mentasta Pass was made by T. G. Gerdine in At tho same time the geology of this region, wliirh includes the placer :old deposits of Chistochina River, was studied by Mendenhall.' Tliis paper describes the continuation of that work in 1910. An account of the field work on which it is based is given on page 10.

The descriptions tliat follow deal principally with thQ two placer gold fields coiimxonly known in the (o|)per River region by the names of tlieir most important gold-producing creeks — Valdez Creek and Slate Crock. Those two Holds lie in the foothills on the south side of the Ahuska Range. Thoy are about 75 miles a|)art and are associated here because of their geographic position and the fact that they were visited in tho course of tho same summer's work rather than because of similarity or relationship hotwoon them. The two districts are represented in Plato VII (p. 114).

Valdoz ( Yook is a of Susitna River from the east and joins it a little more than 15 mihs south of tho nearest of the several glaciers from which tho Susitna rises. wSIato ( Vook, on the other hand, is a trihutarv of Chistochina River, which in turn is a northern branch of Rivor and is one of the throe largest streams draining that of tho Ahiska Range included within the Copper River basin. Both districts lie within the foothills of the Alaska Range, and their principal gold-proilucing streams are just above timber lino— that is, between 2,500 and .'.000 foot above sea level. Fortunately, however, they are so near timber that the supply needed for fuel and for mining is procured with little difficulty.

This paper Is a preliminary statonicnt of the results of a golodc ro<'onnalssancf by the writer and B. L. Johnson in the uppiT Susitna and Chlstoehlna districts In 1910; it will followed at a later date by a more extended account of the upiwr Susitna <lLstrict.

Mendenhall, W. C, Geology of the central Copper Ulvcr region, Alaska: Prof. Taper U. S. CJeoI. Sonray No. 41, 190&

The Uppeb Susitna And Chistochina Districts. 113

The nearest shipping point on the coast is tlie town of Valdez, which 19 about 130 miles ahnost directly south of a point midway between Valdez and Slate creeks. Since the discovery of gold in these two districts all suppUes required by the miners have been brought in over the military trail from Valdez in winter. Freight for both districts passes over the same route from Valdez to Gidkana, but at that point the winter trails separate. Supplies for Valdez Creek are taken up Gulkana River and one of its western branches to a low divide leading to Maclaren River. Thence they are carried down the Maclaren to the Susitna and up the Susitna to Valdez Creek. These trails will be described in more detail in the account of Valdez Creek.

From Gulkana supplies for Slate Creek are taken up the Copper and the Chistochina to the camps at the head of the latter stream. These two winter trails will be better understood by referring to the map (PI. VII).

The military trail, which for ±2 years has been the route of entrance to the Copper River valley, has been turned into a road, and it was possible at the end of the summer (1910) to take wagons all the way through to Fairbanks from Valdez. This improvement is a great benefit to all the region in touch with the road, and the members of the Alaska Road Commission and those working with them deserve much credit for what they have accomplished. There still remains a great deal to be done in the matter of bridges and ditching, but those who have traveled over the old trail and the new road can not fail to appreciate the progress that has been made. A road also has been cut through from Willow Creek, between Tonsina and Copper Center on the military road, to connect with the Copper River & Northwestern Railway at the mouth of Chitina River, and when the bridge over Tonsina River is constructed communication between the coast and the upper Copper River valley will bo far easier than it has been. This road will undoubtedly draw considerable traffic away from Valdez but will avoid the delays and difficulties that are presented by Thompson Pass in the winter and spring.

In the matter of mail communication with the outside, the Chistochina region is more fortunate .than Valdez Creek. Gulkana is the last post office south of the Alaska Range on the military road out of Valdez, but a second mail route between Gulkana and Dempsey (near the mouth of Chisna River) by way of Chistocliina was in operation in the summer of 1910 and a regular bimontlily service had been established. There was no mail service between Gulkana and Valdez Creek. The miners on Valdez Creek, however, received letters and a limited number of papers from Gulkana by an Indian messenger who was paid by private subscription. It would seem as 98319— Bull.-480— 11 8

114 Mineral Resources Of Alaska, 1910.

if a summer service, wliich would benefit a greater number of people, could be established by carrying the mail from the coast to some point like Paxsons or Yosts on the Valdez-Fairbanks road, from which branch routes would connect with Slate Creek, 25 miles to the east, or with Valdez Creek, 65 miles to the west. Such an arrangement would make the most of the advantages oflfered by the military road, but these more northern branch trails, especially that to Valdez Creek, would hardly be practicable in winter, as both are above timber line and afford no wood for fuel.

Although, with our present knowledge of the facts, it is too much to say that the gold occurrences of Slate Creek and Valdez Creek are exactly aUke, there are, nevertheless, many points of similarity between them. The source of the gold in both localities is in slates that have been intruded by diorite and related granular rocks. It has not been shown that the slates of the two localities are of the same age, and in fact it appears more probable that they are not, but the intrusions of the slate by the diorite are believed to be approximately contemporaneous, whatever their geologic age may be.

No well-defined and persistent auriferous veins have yet been found in the slates, although small gold-bearing quartz stringers and lenses are present. Nearly all the streams heading in the Alaska Range between Slate Creek and Valdez Creek have shown the presence of gold in their gravels, but in most places the amount has not proved sufficient to make mining profitable. The one possible exception is Rainy Creek, a tributary of Delta River below Eureka Creek, on the west side. Five men were at work there in 1910 and in the early part of the summer had some promising prospects but were hardly making wages at that time. Prospecting on Delta River above Eureka Creek and on Little Clearwater Creek has not been successful, yet gold is present in the gravels. Although gold is widely . distributed in tliis part of the Alaska Range, deposits of commercial importance are localized and few in number. It would seem that the best places for prospecting are in the slate areas, for there is no reason to believe that gold is present in the basaltic rocks and the diorite areas do not yield gold, notwithstanding the fact that the diorite intrusives were most probably connected with the origin of the gold.

Valdez Creek.

General Statement.

Valdez Creek has been a producer of placer gold since 1903, but it was not visited by any member of tlie United States Geological Survey previous to tlie summer of 1910. For that reason and' because the publLslied descriptions of the stream are few and incomplete, it is desirable to make the present paper somewhat more com-

The Upper Susitna And Chistochina Districts. 115

prehensive than would be necessary if the district had been fully described before.

Valdez Creek is approximately 14 miles long, but only a short stretch at its lower end yields placer gold at present (1910). Some of its tributaries, however, produce gold and others probably will do so in the near future. Tliis creek, as previously stated, is a tributary of Susitna River. It rises in the mountain complex flanking the main Alaska Range and flows westward to the Susitna (PI. VII). Its principal branch, Roosevelt Creek, heads in two small lakes that occupy the pass leading from Valdez Creek to Big Clearwater Creek and contributes nearly as much water to the main stream as does the U{)per part of Valdez Creek above the mouth of Roosevelt Creek. The two next largest feeders are Timberline and White creeks. Rusty CVeek and Lucky Gulch are tributaries of White Creek and Roosevelt Creek, respectively. All these tributary streams are on the south side of Valdez Creek proper.

Valdez Creek flows tlirough a strongly glaciated valley. South of it and around its headwaters arc liigh, rugged mountains, but the mountains north of the lower or western end of the creek smooth, rounded contours when viewed from the southern side, although the north slopes are precipitous. The valley is wider than most of the smaller stream valleys in the region to the east, especially at its lower end, where the valley of Valdez Creek joins that of Susitna River. Tliis difference is pronounced, yet less so than that shown by the tributaries of Susitna River on the west side opposite Valdez Creek and to the northwest in the direction of Broad Pass. All the northern tributaries of Valdez Creek are comparatively unimportant, as regards both their present economic value as gold producers and the quantity of water they contribute to the main stream. Tliey drain the smooth north slope of the valley and have cut deep gulches and canyonlike channels in its surface. The larger southern tributaries, on the other hand, occupy steep, strongly glaciated valleys and head in cirques that either contain the dwindling heads of old glaciers or were but recently vacated by them.

Valdez Creek has an abundant supply of water wliich is available for mines on the lower 4 miles of the stream and which can be secured with little difficulty and at small expense, considering the very high cost of supplies and equipment in this region. A rough measurement was made a short distance above the canyon for the purpose of obtaining data on which to base an estimate of the amount of water available for use below. Tliis measurement, made at the end of August, showed from 3,000 to 5,000 miner's inches. These figures are, however, only a very rough approximation, and a long series of careful measurements should be made before installing any expensive plant to use this water.

116 Mineral Besources Of Alaska, 1910.

Trails And Transportation.

The first miners on Valdez Creek came from Valdez by way of Valdez Glacier and the upper Klutina Valley. They crossed Klutina Lake on the ice, and after ascending St. Ann River to Hudson Liake they traveled north to the Susitna Lakes by way of Tazlina Lake, and then descended Tyone Creek to Susitna River, where they esta"b- lished a base camp and began their prospecting. Diuing the first year or two of work on Valdez C-rcek supplies were brotight from Valdez by this route, but it was then abandoned in favor of the better route by way of Gulkana, already described. Ail freighting is now done over the Gulkana trail. The smooth ice of Gulkana, Maclaren, and Susitna rivers gives a low-water grade for hauling that is practically continuous from Gulkana to Valdez Creek, for the divide between the Gulkana and Maclaren drainage, where crossed by the trail, is too low to Ix') noticeable. The distance from Valdez to Gulkana is 128 miles and from Gulkana to Valdez Creek is approximately 125 miles. The cost of freighting from Valdez over this trail averages nearly 30 cents a pound (1910).

An attempt to establish a new winter route to the coast by way of Susitna River was not considered successful and has not been renewed. A few supplies, however, arc brought in from Fairbanks each year by way of Nenana River and Broad Pass.

There is a choice of sovtM-al routes for summer travel between Valdez Creek and the militia'v road. The one usuallv followed is an old Indian trail from Bear Creek near the mouth of Gulkana River directlv nortiiwest to Valdez Creek, a distance of 105 miles. This trail is in timber all the way and has the disadvantage of being exceedingly wet iii the o|)en season. Another route, used only a few times, is from Paxsons to the west fork of Maclaren River and thence to Valdez Creek way of the Roosevelt Lakes. This trail is about 05 miles lon, it is above timber line after it leaves Paxscms except in the vicinity of the Tangle Lakes and has another in that it crosses a number of rides, in height from 500 to 1,000 feet al)<)ve the valleys. The and easiest trail is from Yosts, or some near-])y on the military trail, to Maclaren River by way of Eureka Creek, and thenee to Valdez Creck way of the Roosevelt Lakes. This trail is above timber exce])t at Delta River. The only ridges of which it crosses are the forks of Maclaren River and Maclaren River and Little Clearwater Creek, both of which can be avoided hv a little labor in brushing out a trail. This northern trail, however, is very little shorter than that from Paxsons.

The Vppeb Susitna And Chistochina Disthicts, 117

Geherai. Oeoloot.

The statements that follow regarding the geology of Valdez Creek apply to the uninediate vicinity of tiio creek (see fig. 15), yet the same geologic formations are widely distributed in the region both to the east and west.

Slate forms the bedrock of Valdez Creek throughout its length except for a short distance at the upper or east end. Locally the slate has been changed mto schist. This change was brought about

FiouBE IS.— Geologic sketch map of the vidolly of Valdet Creek.

by the intrusion of granite and related liglit-colored granitic and porpliyritic rocks into the slates and by moderate fooling, which probably took place during and aftiT the time of granite intrusion. The slates are associated witli limestone and shale beds that contaui Upper Triassic fossils, but convincing evidence of tlieir Mesozoic age is still lacking.

South of the slate area is a belt of dark basaltic rocks whose Btratigraphic relation to the slates has not yet been

118 MINERAL RESOURCES OF AIJiSKA, 1910.

beyond question. The basalts have a bedded appearance and have undergone deformation that is shown by folding. They are best developed on Windy Creek.

The slate area is bounded on the north by diorite, which is exposed over a large area that includes the head of Valdoz Creek and most of the ridge north of it. The diorite intrusions are younger than the slates but may possibly differ much in age among themselves, since there is a wide variation in the amount of metamorphism that has taken place in them. At the head of Valdez Creek part of the diorite to be fairly fresh and little altered, but in the ridge north of Valdez Creek the <Jianges are great. The lias a gneissoid structine and a pnmouneed cleavage, whose {)roduction was accompanied by the formation of such minerals as cyanite and garnet in the adjacent scliLstosc sediments. Great alteration has taken place in the sedimentary rocks adjacent to the granite intrusions north of Valdea Creek, and the scliLstose <'haracter is liigldy developed there. Schi tosity doereasas as (hstanco from the granite intrusion increases till it ])ractically in the slates south of Valdez Creek, although the regularity of the dei*reaso is affected in some degree by smaller intrusive masses such as that on Timberline Creek.

The principal nn'k formations of the Valdez Creek vicinity, then, are the <hirk basaltii*. rocks of Windv Creek, the slates and scliists into which the slat<\s that, occupy most of lh( Creek valley hayc and th( jjranite that was intruded into the slates and is most widely noitli of

The of Vahh'z (I'cck <*onsist cldeflv of takis niatciial that, mantles thci mounlain slo])cs and the gravels that cover the vallev iloor. i:i'av<'l deposits of course, the str(*ani wash, ])iit ihcy ar( made up chicny of deposits and are intimately asso<'dialed in their oi'iin witli tlie glaciation of the valli'V. Tiu J'ock (v. irments ai( ciiiellv slate and scliist. with mucli associated nuteiial. Tin* levels contain an uncommon |)roportion of laru:( iianiio l)(>elders. tlie jXiriod of maxinnnn la<'iation CifM'k valley and tlu adjacent Susitna Valhn' lilhwl with hiil Susitna i<'e was able to contrihuti to the <xi'avels of l<>wer CicM'k sonu rock foreign to th(*, valley. A veiv important. of Valdez Crerk. in connecticm

I

witli the (list rihut ion of iis L::iavel depixit, is the i'acl tiiat the present stream i-hannel is not the oriiiinal cliann:'!. Bel'ori t Ih |>resent wasdevelo|)(Ml had <'ut an ])ut shall<>w<*i<'anyon in bedrock. This was overridiien ])y from noilli and eai and filed

ft

with gravel, and wlien at tlw ice disapjx'aiHul and (lie estabhshed a new clmnnel for its coins( did not with its old <me. The present eanyon is enl intiMhe slate>(i() i'eei than the ohi canyon at tlie phice of tlieir intersection on claim ''No. 2

The Xjppeb Sxtsitna And Chistochina Districts. 119

above" and is now 170 feet below the top of the benches on either side of the creek at that locality.

Economic Geology.

The placer gold of Valdez Creek has its chief source in the slate area south of the creek. This is fully proved by the results of prospecting on the tributary streams. The tributaries that flow into the main stream from the north have been found to carry only a small quantity of gold, not enough to encourage prospecting. On the other hand, dil the gulches and creeks that cut the slates to the south carry gold, and in many places even the loose sUde rock on the slopes yields a good string of colors on panning.

Among these southern tributaries Lucky Gulch has been a gold producer for several years and Rusty and White creeks give promise for the near future. There appears to be Uttle doubt that the hill between Valdez Creek and White Creek extending east to Roosevelt Creek is one of the principal areas of mineralization, although it is not the only one. The slates are cut by light-colored igneous intrusives and by small quartz veins. Many of these quartz veins carry gold in sufficient quantity to encourage careful examination, yet little attention has been given to prospecting for lode deposits of gold in the district.

The total production of the Valdez Creek district is about $260,000. Mining operations in this district in 1910 were restricted to a few creek claims on Valdez Creek, to the Monahan tunnel. Lucky Gulch, and Rusty Creek. Assessment work was done on many other claims, but this was only to hold the property for future development.

The creek claims on Valdez Creek that have received most attention are Discovery claim," 1 below," 'No. 2 below," '*No. 2 above," and '*No. 3 above." (See fig. 16.) 1 above" includes a deep rock-walled canyon too narrow to permit mining. The richest of the productive claims were Diseovery claim," 'No. 1 below," and the lower half of 2 above." There is Uttle variation in the character of the gravel on the creek claims. It ranges from 3 to 8 feet in thickness and consists of slate, schist, and granite, together with a small proportion of light-colored ])orphyritic intrusives and dark basaltic and tuffaceous material. An important characteristic of the gravel deposits is the great proportion of large granite bowlders. Such bowlders are difficult to handle in the cuts and add much to the cost of mining. Many of the larger ones are too licavy to lift with the ordinary means at hand and are moved only by undermining them on one side and causing them to roll over.

The gold in the creek claims shows considerable variation in its appearance. Part of it is flat and smooth, but another is rough and little worn. Gold from the claims above the Monahan tunnel

Mineral Resources Of Aiaska, 1910.

sliows less wear than that below. A large amount of "ruby sand" or garnet is associated with the gold, yet leas "black aand" is present than might be from the quantity of igneous mftterial contained in the gravel. A little more than one-third of ihe total gold production of Valdez CVeek from 1903 to 1910 has come from these creek claims, but it is expected that their yield will be considerably less from now on, because so far as known most of their richest gravel has been mined out.

Tlie Monohan tunnel is of particular interest, both geologically and because it has yioUleil more gold than any other single property in tlie district and nearly as much as all the others together. Iliis tunnel follows Uio bottom of an old lilleil-iji canyon in the slates, wiiidi

iiijikcs an angle> of aliout 4.'i wiili tlic pn-sml cmnsic of Valdez Creek lit their jMHiit of iiiterse'tion. If sltuls on cliiini "Xo, 2 above" at an clcYiilion of iiiiproxinuitcly f>() feet iihovc the present creek bed and is ilrivcn across thi- north half of tlic crc<>k clnim into ihc adjoining Tanmijioy bench rliiini. (See fii,'s. Ifi and 17.) Its position south of Valdez ('reck lias not been ilctwrniincd. Its [>rcsenl Icnfjth is about feci. TJie course of Vidilcz Creek iit the tunnel's month is eastnortheast; that of thetuiini'l itself is north-norlhea.st. The distance from the tunnel floor to the surface of the bench above is 110 feet,

THE UPPEB SUSITNA AND CHI8T0CHINA DlSTBICTS. 121

which represents the depth of gravel filling in the old canyon, (or on either side of thetunnel slate bedrock isseen outcropping within afew feet of the surface of the bench. The canyon is not straight, yet the variations in its course so far discovered are not important, unless the last abrupt turn to the east near the end of the present workings marks the binning of a new course.

Bedrock in the tunnel is slate or schist. It is not fractured enough to permit gold to penetrate it far. Crosscuts from the tunnel, one about 100 feet to the west and one 60 feet east, show that the bedrock rises steeply on either side that the walls are waterwom. The measurements in these crosscuts, however, do not indicate the general width of the canyon, for the tunnel in most places is at or near the canyon wall and the measurement of 100 feet is probably a maximum. In many places the width is much less than that.

There is no difference between the kind of rock material making up the gravel in the old canyon and that in the creek, but there are variations in its character. The lower 50 feet of gravel in the canyon contains flat granite bowlders with rounded edges, rounded slate and schist fragments, and fine black clay. Above ±Z-

this the canyon filling shows

mnr* nf lapfffl (TranitB 'oubb 17 Dtagrammflllc bbcUod showing relation ol the more Ol tne large granite ||oiihuHmm*l K. fOd-t CrMk The old ™nyon WWr bowlders, but they are sects the present channel at m angle oUS* ami is WiMt

round rather than flat, the '"'

gravel is not so clean as below, and the whole deposit has an appearance of greater disorder.

Gold is found chiefly in the lower 5 feet of gravel, although there is fine gold in the upper part also. Most of it is contained in the hard black clay and fine rounded slate gravel. The gold is coarse, flattened, and smooth for the most part, yet a few rough nuggets, some of them containing quartz, are present. Although heavier, it much resembles the gold of the creek claims below.

If it should become desirable to apply hydraulic methods in the mining of these bench gravels, the favorable conditions for obtaining a good water supply and a dump for tailings are to be noted.

Aside from the Monahan tunnel, mining operations were conducted in the bench gravels of this creek at one other locality. A small tributary joins Valdez Creek at the upper end of claim "No. 2 below." It drains a slight depression southeast of the main creek and at its upper end is probably not over 175 feet above the creek. At its lower end it drops over the high rock wall of the main stream, where an 'excellent dump for tailings is thus provided. Water was brought

122 Mineral Resources Of Alaska, 1010.

from Timberline Creek, a distance of 1 J miles, by a ditch and a short line of pipe for the purpose of moving gravel on the bench at the mouth of the little stream, and mining operations were carried on in 1909 but were not continued in 1910. The gravel resembles that of the creek except that it is cleaner and contains more sand. The same trouble from bowlders was experienced here as on all other parts of Valdez Creek.

Lucky Gulch is a small gulch tributary to Roosevelt Creek near the junction of Roosevelt and Valdez creeks and is about 6 miles f the main camp on Valdez Creek. It is a steep, narrow gulch, Uttle more than a mile long, and draws most of its water from melting snow. Since the gulch is on the north slope of the mountain, the snow that drifts in and it in winter melts slowly in summer, thus both preventing work in the eaily part of the open season and providing the only source of water for mining later in the summer. The slate bedrock of Lucky Gulch dips about 20° N., so that the dipof the slate and the fall of the creek are about the same in many paces. On account of tlie narrowness and stee])ness of the channel there is no opportimity for the accumulation of any considerable body of gravel, and such as does accumulate consists of angular fragments and slabs of slate. Well-washed and rounded gravel is present only in small amoimt.

The gold from Lucky Gulcli is coarser than tliat from any other part of the Valdez Occk district. In it is rough, with spines and yet soino of the larc ])iccos arc llattenod and smooth. Large nuggets form a very considerable ])art of the product of the creek. One was found in 1910 that weijluMl 32 ounces. The largest ever found 52 ounces. Many of the nuggets contain sugary quartz, and il is evitk'Hl that the gold is of local origin and has traveled only a sliort distjince.

A short season and small su])])Iy of wafer in large measure the advantage (hie to the fnnnlom from granite bowlders that Lucky Gulcli enjoys (ver Valdez (Yeek. Large of slate are common ii*i the gulch, most of th(*se cnii h(* broken with a sledge, or, if this fails, with a small cliarge of and thus removed. The gravel de])osits an* worked ])y booming or sometimes with a small nozzle and hydraulic hose. Part of the irulch has been worked out, but there still remains a large amount of ground to be exploited.

Rusty Creek is miles east of tin* Valdez (Yeek cam]) and is the princi])al tributary of Wliile (Veek. The valleys of t hese two streams, White and Rusty creeks, arc tlu largest that have Ikmmi cut into the mineralized slate mass south of CYeek. They head in the complex of slates, tufTs, and basalts of the ridge north of Windy Creek, and run north through the slates t() Valdez Creidv. Both of these streams oiler promising to the [)rospeclor. Such pros-

The Upper Susitna And Chistociiina Districts. 123

pecting as has been done on White Creek has not resulted in any definite results and was carried on under much difficulty and expense, due in part to the high cost of supplies and lumber but principally to troubles that arose from depth of gravel and much water. Such results as were obtained did not appear to the miners to warrant the heavy expense required for thorough prospecting at that time.

Prospecting on Rusty Creek has been conducted for three years in the face of many difficulties and much expense without any returns, and it was not till the end of the 1910 season that results of much promise were obtained. During the three years preceding, a large cut several hundred feet long and over 25 feet deep in places was made in the creek channel just at the place where the White. and Rusty Creek valleys join Valdez Creek valley. Tliis was accomplished by booming — that is, by the use of a dam with an automatic gate which opens periodically and releases a large volume of water. The water rushes through the cut, tearing up the gravel and washing it away. By this method a deep, narrow cut, begun in the expectation of reaching bedrock at no considerable depth, was made in the gravel deposits. The cut follows the east wall of an old gulch or canyon and exposes the northward-dipping slates on that side, but the bottom of the canyon was not reached at the end of the working season of 1910.

The gravels filling the old gulch include an upper deposit of unsorted glacial dfibris from 10 to 20 feet thick, made up of slate and basalt. Below this is another deposit of fairly well sorted gravel and coarse sand with a distinct cross-bedding. There are many large bowlders in the cut, derived chiefly from the upper glacial deposit. Most of them are basaltic in character and come from the head of Rusty Creek. There are also a few granite bowlders.

Encouraging gold prospects have been secured from the projections or benches of the rock wall on the cast side of the cut and especially from the bottom of the cut, where work ended in 1910. The gold is very rough and briglit. Few pieces of greater value than 20 cents were found during any of the mining until the end of last sctison, but there was a noticeable increase in coarseness in the last gold taken out that lends encouragement to the beUef that the bottom of the cut is now near bedrock.

Rusty Creek and White Creek give greater promise for extension of the gold-producing ground of the district than any of the other streams, and it is believed that they should be thoroughly ])r()s- pected. It is impossible to predict whetlier the concentration of gold in their gravels will be found sufficient to yield rich placer deposits, but the streams cut mineralized slates that are known to be gold bearing and there has undoubtedly been some concentration of gold during the time that erosion of the slates has gone on.

124 MINERAL RESOUBCES Ol ALAsKA, 1610

Timberline Creek tilso is anotlier possible source of placer gold, as it Iieads in tlie mineralized slate area. A little prospecting has been carried on, but witliout particularly encouraging results. The discovery of other gold-producing gravels in the Valdez Creek district is highly desirable, because it is evident that most of the rich channel gravel of the original creek claims is worked out.

CmSTOCHINA GOLD FIBIjD.

All the gold-producing ground of the Oiistochina district lies between the west and middle forks of Cliistochina River. It includes Slate Creek and Miller Gulch, Cliisna River, its tributary Ruby Creek, and the tributary of the Middle Fork called Lake Creek on the older maps but now known to the miners as Lime Creek. To complete the list of locaUties where mining operations are conducted in tlus district, there should be added that on the west side of Cliistochina River, near the moutli of Chisna River, where the post office, Dempsey, is situated.

The geology of this small area was described by Mendenhall and may be stated briefly as follows: South of tlie depression formed by the valleys of Slate Creek and the upper part of Chisna River is a series of tuffs, quartzites, and conglomerates with associated igneous rock, called the Chisna formation. This formation is conspicuous bocaiiso of its red color, due to the oxidation of pyrite in tlie rocks that form it. North of tlie (lo])session is the Mankomen formation, which in this vicmity is made u]) of limestone and sliale, locally nictaiuorpliosed to slate. These two formations are separated by a fault of unknown displacement by which the Chisna formation is raised relatively to the Mankomen. The Mankomen formation is of late Carboniferous ixe. The Chisna formation is ohler, but probably Carboniferous also. Patches of coal-bearing Tertiary shale have been in the channel of Slate Creek by minhiti:

During the last 11 years, since the discovery of gold in 1899, most of the rich creek gravels of Slate Creck and Miller Gulch have been worked out, yet there still remain creek claims of lower grade and bench gravels that have not ])een touched. TJie total production of Slate (Veek and :Miller (lunch Ls about

There are about 20 creek claims on the channel of Slate Creek and 7 on Miller Gulch. Between 40 and 50 men were employed in the Cliistochina district in most of whom were on vSlate Creek. They were scattered along at several cani])s, from 3 below" to the lower end of the creek.

Mendenhull, W, C, (i?ology uf the ceutral Copper River district: I'rof. I'aiKT l. S. Geol. Survej No. 41. 1905, pp. 24 et seq.

The Upper Susitna And Chistochina Districts. 125

The first three claims above the mouth of Slate Creek are virgin ground but are difficult to work because of the depth of the gravel and the large amount of water. A hole 21 feet deep near the south side of the gravel bar did not reach bedrock. Tailings from the claims above are another source of trouble. A dam was built on the lowest claim in 1910 to furnish water for booming a low bench on the north side of the creek. This was not completed in July, 1910, when the creek was visited.

On the fourth, eighth, and ninth claims above the mouth of Slate Creek mining was confined to the bank on the south side of the stream. A heavy deposit of glacial material, consisting of blue clay or glacier mud and large bowlders, is exposed on that side. It is overlain by a deposit of frozen yellow talus material or shale rock from the mountain side on the south, ranging from 5 to 25 feet in thickness. The glacial material contains gold and is exploited by undermining and caving. Bowlders are piled back from the cut to form a channel along the foot of the bank and then the water is turned in to cut the bank, and wash away the fine gravel. Afterward the remaining gravel and gold is shoveled into the sluice boxes. This work is slow and very dangerous, because the high bank of frozen gravel above sloughs off continually as it thaws and at times breaks down in large masses, so that men must be constantly on the alert and ready to jump to a place of safety.

The largest force of men on the creek was at work near the mouth of Miller Gulch on ground that has been the richest of the district and is still producing gold. This Tacoma claim, as it is called, together with the lower part of Miller Gulch, has yielded much more gold than all the other claims together. The gravels of Slate Creek above Miller Gulch are of lower grade than those below, and fewer men have been employed there, yet their contribution to the gold production of the creek is important.

There was less mining on Miller Gulch in 1910 than in previous j'ears. This was not due to the exhaustion of gold-bearing gravels. Work was partly suspended in order to avoid covering unworked gravels in Slate Creek with tailings and will be resumed another year. The water supply of Miller Gulch available for mining operations is small, so that it has been the custom of the two principal claim owners to use it in alternate vears. In this wav all the bed of the gulch has been worked out, but there still remain bench gravels that will be exploited as soon as the ground below can be used for dumping.

The most important gold-producing creek in this district, after Slate Creek and Miller Gulch, is Ruby Creek, which lies just east of Slate Creek across a low, flat divide. Ruby Creek has tlirown out a broad fan of gravel extending outward in a semicircle from the point

126 Minekai. Kesources Of Alaska, 1910.

whoro tlio creek loaves the narrow pilch in the mountains at the head of Cliisna Kiver, thus forming a smooth slope to the west, south, and east. The creek has cut a channel rang from 15 to 20 feet in depth in tliis avel fan. The travels are gold beariag and mining is carried on in them, and also in a short bend of filled and abandon channel at the head of the fan just witliin the gulch. From some cause the creek cut a new rock-walled chaimel within a few feet of its former channel at the point where it leaves the mountain. The gold content of the gravels that filled the old channel is low but still great enough to encourage ])rospecting and pay the bare expense of doing it. Work is greatly hintlered ])y snow and ice, which in some summers do not melt, so that even the water for sluicing is brought through a tunnel in the ice. Bedrock has not been exposed in the channel of Ruby Creek where it crosses the gravel fan. The false bedrock wluch holds tlu gold is a gravelly clay bed but a few inches in tluckness. Ruby Creek, in cutting its present channel, has concentrated the gold contained in the gravel removed and has left it on these clay beds. Only a few feet of gravel is shoveled into the sluice boxes and (*aro is used not to below the false bedrock into the barren gravel beneath.

Mining operations on Lime Creek at the head of the middle fork of Clustochina River are on a bench well above the creek and about 11 or 2 miles east of the divide the heads of Lime Creek and diisiia RiviM". Tlie section in mining sliows about 6 feet of heavy bowlder wash on hhie glacier clay containing small angular fragments, which is overlain in turn by more of the heavy wash, the whole section having a thickness of 30 to 40 feet. A large amount of gnuMistont* is present in the deposit and is associated with slate, limestone, conglomerate, and granite. The richest deposit of gold is found in a rusty gravel seam on the blueclay bedrock. Copper nuggcMs ranging in size from shot to pieces of several pounds an caught in the sluice hoxcs. They resemble those of Chititn and Dan crcM'ks, in the Niziiia distiict, and like them are derived fi'oni in basalts or greenstones, (ireenstone that resembles the Nikolai greenstone is exposed in the mountain northwest of Lime Creek.

Work on Chisna Itiyer was in the nature of assessment work and prospecting. Cousidera])le gi'ound is Jield there hy (liU'erent peisons awaiting the timc when the introchictinn of hydraulic nniclunerv or oth(>r economical mining metliods shall make mining more ])rofitable. At present the cost of lahor and devel<>p?nent of much of the gold-heading gravels. AVages are 810 a day without board, and freight <'osts from 20 to 25 cents a pound

SchradtT, F. C, anl SpiTuvr. A. ('., Tlu' i,'f()l(>v;y aii'l inincral rrsoiircis of a of tin- Copper River dIstrU'l, Alaska. asiMH-ial of iln* l'. s. CnA. Survey. lmi. p. Ml Moilii. F". U., anl Maddren, A. G., Mineral rosourxt's of ihc Kofsina-Cliiiinanj:ioii, Ahirfka: iJuU. L .S.lit'ol.Survi-y No. ;i74, lUU9,p. 23.

The Upper Susitna And Chistochina Districts. 127

Work at Dempsey is also in the nature of prospecting. Considerable time has been expended in driving a tunnel into the bench gravels west of Chistochina River in the belief that an old channel would be discovered. The gravels yield some fine gold.

Mendenhall regarded the slates of the Mankomen formation as the source from which the placer gold was derived. .This conclusion appears justified by the distribution of gold in the gravels, the character of the gold itself, and a study of the geology of the region. It seems evident, for instance, that the richness of Miller Gulch was due to local mineralization of the slates and concentration of gold in the gravels formed during erosion and weathering of the rocks containing it. Failure to find important lode deposits can not be considered as evidence against this source of the gold any more tlian the failure to find large nuggets in a gravel de[)osit is evidence that no gold is present. The presence of bowlders of granite, liomblende porphyry, and other rocks from the main range nortli of wSlate Creek is one of the results of former glacial activity but is not in itself proof that the gold of Slate Creek was introduced in the same way.

If the principal source of gold in this district is in the Mankomen formation and the gold of Cliisna River is derived from that source, as is indicated bv the fact that so far as the writer knows these streams cutting the Chisna formation are not gold bearing except where they have received some contribution of foreign gravels from the north, it is probable that rich pay streaks with coarse gold should not be expected on the lower Chisna and Chistochina. The hope of prospectors there should be for the discovery of large suppUes ot low-grade gravels that may be exploited in an extensive way by economical means. This statement is believed to be valid unless it shall be sliown that there is some other source of the gold than that referred to previously.

PRELimNART REPORT ON A DETAILED SURYEY OF PART OF THE MATANUSKA COAL FIELDS.

By G. C. Martin.

Introduction.

The purpose of this paper is to present briefly the more important practical results of a detailed geologic investigation qi the area covered by the Chickaloon special map. This area ifljdudes the commercially more important part of the Matanuska coal fields, which is situated in the south-central part of Alaska about 30 miles northeast of the head of Cook Inlet.

The larger geographic and geologic features of the Matanuska Valley are described and all the information then available concerning the coal is given in earlier publications/ to which the reader is referred. The contents of this paper are but the summary of and the provisional conclusions from the result of the detailed investigations of 1910, which will subsequently be published in full.

Geologic Outwne. Genbral Featubes.

Among the more important geologic results of this investigation is the acquisition of a considerable amount of new information concerning the local stratigraphic sequence. These facts will be presented in detail in the final report. The following table gives a summary of the geologic succession of the rocks in accordance with tlie new information:

Martin, O. C, A reoonnaiasanoe of the Matanuska coal field, Alaska, in 1906: Bull. U. S. Geol. Survey No. 2M(), 1000, m pp. Paige, Sidney, and Knopf, Adolph, Oeologlc recoTinaiiwance in the Matanuska and Talkpotna basins, Alaska: Bull. U. S. Oeol. Survey No. 327, 1907, 71 pp.

SURVEY OF PART OF MATANUSKA COAL FIELDS. General sequence of rocks in area covered by Chickaloon special map.

Age.

Character of rocks.

Thickness.

Quaternary.

Alluvium, terrace gravels, and moraine.

Fed. 0-300+

Pliocene (?).

Lavas, capping Castle Mountain.

Intrusive rocks, mostly basic.

Miomie (?).

Conglomerate, on Castle Mountain and Wishbone Hill.

3,000

Eocene.

Shale and sandstone, with coal bods.

2,000±

Arkose, conglomerate, and shale, without known coal.

2,000i:

Upper Cretaciwas.

Sandstone and shale.

4,500±

Lower Cretaceous (?).

Limestone.

200i:

Lower Juraasic.

Volcanic breccias, agglomerates, and tuffs.

1,000±

Early Mesosoic or older.

Granitic rocks.

Gncissic rocks.

Crystalline Rocks Beneath The Coal.

The rocks grouped under this heading in this discussion and on the geologic map (PI. VIII) include the gneissic and granitic rocks, the Jurassic volcanic breccias, agglomerates, and tuffs, and the possibly Cretaceous limestone represented in the general section above. These rocks are grouped together because of the facts that they are all known to be far beneath the coal and that none of them are individually of importance in a discussion of the coal.

Large bodies of gneissic and granitic rocks, which are intimately associated with one another and which have not been separated, occur in the Talkeetna Mountains and are present along most of the northem border of the area represented on the map.

Jurassic volcanic breccias, agglomerates, and tufis occupy an area east of Kings River along the northern edge of the area shown on the map, and are probably present also in the valley of Coal Creek. These rocks are overlain by a presumably Ijower Cretaceous limestone which has been seen only along the northern border of the mapped area east of Kings River.

98319°— Bull. 480-11

PRELIMINARY REPORT ON A DETAILED SURYEY OF PART OF THE MATANUSKA COAL FIELDS.

By G. C. Martin.

Introduction.

The purpose of this pa|)er is to present briefly the important practical results of a detailed geologic investigation gt the area covered by the Cliickaloon special map. This area includes the commercially more important part of the Matanuska coal fields, which is situated in the south-central part of Alaska about 30 miles northeast of the head of Cook Inlet.

The larger geographic and geologic features of the Matanuska Valley are described and all the information then available concerning tlie coal is given in earlier publications/ to which the reader is referred. Tlie contents of tliis paper are but the summary of and tlio provisional conclusions from the results of the detailed investigations of 1910, wliicli will subsequently be published in full.

Geologic' Outline.

General Featxjbes.

Among the more results of this investigation is the acquisitiiMi of a coiisideiahle amount of new information concerning tlic local stratigrapliic sequence. These facts will be presented in detail in the sinai report. The following table gives a summary of the geologic succession of the rocks in accordance with the new information:

Martin, O. C, A rroonnaissiuice of the Matanuska coal flehl, Alaska, in 1905: Bull. U. S. Geol. Sun-ey No. 2s), llMMi. 3'i pp. Paipp. and Knopf, Alolph, Geolofrio ivcouuaiiisance in the Matanuska and Talkpetna Ixi-siui*, Alassku: Bull. U. S. CJeol. Survey No. 327, 1907, 71 pp.

SURVEY OF PART OF MATANUSKA COAL FIELDS. General sequence of rocks in area covered by Ckickaloon special map.

Age.

Character of rocks.

Thickness.

Quaternary.

Alluvium, terrace gravels, and moraine.

Feci. 0-300+

Pliocene (?).

Lavas, capping Castle Mountain.

Intrusive rocks, mostly basic.

Miocene (?).

Conglomerate, on Castle Mountain and WLshbonc Hill.

3,000

Eocene.

Shale and sandstone, with coal bods.

2,000±

Arkoso, ooDomcrate, and shale, without Imown coal.

2.000±

Upper Cretaceous.

Sandstone and shale.

4,500±

Lower Cretaceous (?).

Limestone.

200i:

Lower Jurassic.

Volcanic breccias, agglomerates, and tufls.

l.OOOi:

Early Mesocoic or older.

Granitic rocks.

Paleocoic.

Gneissic rocks.

Cbystalline Bocks Beneath The Coax..

The rocks grouped under this heading in this discussion and on the geologic map fPl. VIII) include the gneissic and granitic rocks, the Jurassic volcanic breccias, agglomerates, and tuffs, and the possibly Cretaceous limestone represented in the general section above. These rocks are grouped together because of the facts that they are all known to be far beneath the coal and that none of them are individually of importance in a discussion of the coal.

Large bodies of gneissic and granitic rocks, which are intimately associated with one anotlier and which have not been separated, occur in the Talkeetna Mountains and are present along most of the northem border of the area represented on the map.

Jurassic volcanic breccias, agglomerates, and tuffs occup}' an area east of Kings River along the northern edge of the area shown on the map, and ai-e probably present also in the valley of Coal Creek. These rocks are overlain by a presumably Lower Cretaceous limestone which has been seen only along the northern border of the mapped area east of Kings River.

98319**— Bull. 480—11

130 Minebal. Resources Cf Axaska, 1910.

Mbsozoic Sediment Aby Rocks.

The rocks included under this heading comprise the Upper Cretaceous shales and sandstones of the table on* page 129. They appar* ently have a thickness of at least 4,500 feet. These beds lie beneath the coal-bearing rocks, and consequently the area occupied by them ,.nV: is barren of coal. It should be noted that the character and age ot ;l;r~' these beds were not recognized in the earlier investigations and that they are included in the areas mapped as Tertiary by Martin and by Paige and Knopf.' "o:J

The Tertiary rocks of the Matanuska Valley have been divided a i into three sedimentary formations and include also volcanic intrusive rocks.

Arkose, Conglomerate, And Shale, Without Known Coal.

The basal division of the Tertiary consists of beds predominantly % arkosic and well indurated, which occupy large areas along the north- -x ern border of the Matanuska Valley. These rocks are appfurently S x without coal. They have been separated from the other Tertiary jSn:; sedimentary beds described below on the basis of their predominantly arkosic character, greater degree of induration, and absence of coal, 'sj There is believed to be little doubt that these rocks are for the most v' part low in the local Tertiary sequence and include the basal although there is a possibility that the assemblage represented onx the map includes in part the marginal facies of some beds higher in the Tertiary, as well as higher beds not necessarily marginal but now occurring in structural zones in which they have been deformed to a degree not permitting their separation from the basal or marginal deposits. The thickness of these beds exceeds 2,000 feet.

Coaibearino Rocks.

The coal beds of this district occur in a rather monotonous succession of shales and sandstones. The shales, which predominate over the sandstones in aggregate thickness, are gray to drab, rather soft and inclined to disintegrate on exposure, poorly bedded, and without n well-defined joint planes. Most of the beds are rather gritty and , vary in grain along the bedding. They contain many nodules and lines of nodules of iron carbonate, some of which form fairly persistent beds. The sandstones are yellowish, rather soft, of diverse grain in the different beds and of varying grain in the same bed, for the

1 Martin, O. C, Geologic reoonnaissanoe map of the Matanuska Valley: Bull. U. 8. Geol. Survey No. 289, 1906, PI. III.

Paige, Sidney, and Knopf, Adolph, Geologic reconnaissance map of the Matanuska and Talkeetna legkm: BuU. U. 8. Geol. Survey No. 327, 1907, PL U.

r

Bulletin 480 Plate V

.)g rods POaxfblc exten- /b'kaseBiiddiBk Secbmentai-j-rocka yiTij mcniorOiocoal- without knovm Wfithoul emil *

boHi-ing ' coal

8Ubvey Of Part Of Matanuska Coal Fields. 131

most part feldspathic, and in general the individual beds are not very persistent. The thickness of the coal-bearing rocks is doubtful, but it appears to be at least 2,000 feet.

Fossil leaves are present in both shales and sandstones and are especially abundant and well preserved in the beds carrying iron carbonate.

The coal beds are numerous. There is no evidence as to their exact position within the formation or as to the persistence of individual beds or groups of beds.

The coal-bearing beds are overlain by conglomerates aggregating about 3,000 feet in thickness." These conglomerates are well exposed in the banks of Moose Creek; on Wishbone Hill, which is between Moose and Eska creeks; and on astle Mountain and in the hills east of it. Since the coal-bearing rocks underlie the conglomerate, the areas of the conglomerate are included in the coal area as represented on Plate Vm and in the table on page 134, although there is no positive evidence as to whether workable coal is present in these areas.

The conglomerate is overlain unconformably on Castle Mountain by about 800 feet of volcanic rocks.

Dttbtisivb Bocks.

Several large and many small masses of igneous rock have been intruded into the Tertiary beds in the valleys of Chickaloon and Kings rivers and elsewhere in thp eastern part of this region. These intrusives are known in the valleys of Eska and Moose creeks only in the form of very small dikes and sills, except possibly on the northern border of the region. Gabbro, diabase, diorite, and several kinds of porphyritic and fine-grained rocks are known to be represented among these intrusives.

Gravels.

The Quaternary deposits of this region are of considerable diversity of character and cover broad areas. They include glacial morainic deposits, gravels laid down by glacial waters, terrace gravels more remotely connected with glacial agencies, and the alluvial deposits on the present flood plains.

The terrace gravels are of wide extent and thoroughly mask the underlying rocks up to an altitude of about 1,000 feet, except where the larger streams have cut gorges through the gravels. These gravels are of extreme importance in a consideration of the coal, because they conceal the underlying rocks over broad areas, thus making it very difficult to estimate the actual areas of coal lands or to determine the details of the stratigraphy and structure. The thickness of these gravels ranges from 300 feet or more down to the vanfflhing point.

132 BUNCRAl, RESOL'HCES ALASKA, 1910,

Coal. Btratiqkafhic Position And Sections.

The coal hails of part of tho Mutuiiusku VtJk-y hci-c umlpr dis- r-iisHion are all known to be of Tertiary ago and to agree approxiniutcly in gcncrul atnitigrBphic position with tho coa! of tlio Kenai ' formation on Cook Inlet, They nil occur within the niiciille local division of the Tertiary rocks as grouped in tiiis report. Tlioir exact I position within this division has not been detcrmiuod, but they seem to be in general distributed throughout the greater part of ita thickuess. NotUuig definite is known concerning the persLstonc© of , iniHvidual beds or of groups of bods,

nclailcd measurements of niost of the known coal beds are avniiabli> in previous publications,' to whil-li the reader is for such inrnriiuitiuu. The following sections reconl jneasurements <if expo- 1 surcu which were not seen at the tijno the earlier work was done and represent practically all of the unpuVdisheil information relating to coal

SwUion of ma! hM on fat t-a

Cwii Cmk.

((rour / inUt

t'lnl

.;

Shalu

Shale and coal, altered

.y intniaioii

Strike N. 07

E-;

dip 65

ISI1. pp. lK-2.'>. I'alW. BlilllPJ-, ui

Kiio Gwl

r, Aiioii

onlr

i!l,l, -Maskai D.

1,1'. 3

Oeol,8ur™rNo.l,

19n7.pp.-M

Subvey Of Part Of Matanuska Coal Fields. 133

Section of coal bed on north face of Red Mountain elevation 3,600 feM (about 4 miles north of mouth of Young or Little Kings Creek or S.4 miles west of U. S. L. M. No. 1).

Shale with ironstone nodules. Ft. in.

(oal, exposure obscure and thickness estimated 7 5

Shale : IJ

(oaP 1 2

Shale 1

Shale li

Shale J

Shale f

Total coal 12 2

Strike N, 67° E.; dip 54° SE.

Another coal bed at least 5 feet and possibly 10 feet thick is poorly exposed about 30 feet stratigraphically above this, the intervening rocks being shale with ironstone nodules and sandstone. About 30 feet higher another bed of unknown thickness is present, and 50 feet still higher the smut of another bed was seen.

The presence of coal at this locality adds a hitherto apparently}' unknown coal area to the Matanuska fields.

Sectifjn of coal bed on east bank of Moose Creek j 4.1 miles north of its smith.

Carbonaceous shale with ironstone nodules. Ft. in.

Carbonaceous shale with seams of bony coal 1

Coal 7

Bone and shale 1

Coal 10

Bone 2

Coal 9

Shale with coaly streaks : . . 7

Coal ; 1

Shale IJ

Coal 3

Shale J

Coal 1 5

Bone 1

Coal 10

Nodular shale.

Strike N. E., dip 80° SE.

1 Included in sample No. 11382F, p. 138.

134 MINERAL BESOUBCES OF AT.AftyAj UOO.

Coal Abbas.

Extent.

The areal extent of the assemblage of rocks which cany the coal is indicated on the geologic map (PI. VIII). The map shows also bj a separate pattern the areas which may be underlain by these rocks but in which the lack of exposures caused by the presence of gravels on the surface or the indefiniteness of lithologic character of the exposed rocks makes it uncertain whether the coal-bearing rocks are present.

These are the areas which may carry coal as distinguished from the areas which are known not to carry coal, represented by other patterns on the map. The areas of the coal-bearing rocks" can not be assumed to be underlain wholly by beds of coal of workable character and thickness. Moreover, parts of these areas may have no coal under them. The lack of knowledge as to the exact stratigraphic position of ttie coal beds, the uncertainty as to what stratigraphic part of the "coal-bearing rocks" is represented by the various surface outcrops, and the concealment of the by gravels over broad areas make the precise areal distribution of the coal a problem which can be solved only by drilling or other underground exploration.

The areas of the tracts which it is believed may possibly contain workable coal are indicated in the following tables. The first of these tables shows the areas known to be occupied by the ''coal-bearing; rocks," as dofinod above, and by the conglomerates and other beds which ovcilio thou. The second table shows the areas which mav

aUo be underlain bv these rocks hut in which, because of by travels or because of other lack of definite information, there is a |)<)ssihility that other formations may be present. These estimates are provisional and may he revised when the fiehl notes are fully worked u|).

Areas of .supposed ronl-hfurinff 's.

ftiare miles.

Valleys of Chickaloon and Kinp:s rivers 44

South of Matanuska River, Kiiip:H Mountain and eastern

o<!pe of area shown on special map 8

Valley of Vouni; Creek 3

Valleys of and Eska creeks 19

Arms of posaihlc *rtfti:tiotis nf sn p posnl nm1-}nuir'tmj nn'ls.

Square miles.

TiOWor parts valleys of Kin<;s (Iranite <Teeks 8

Valleys of Mouse and Eska ereeks 16

Structi'Ral Coxditioxs.

It is not practicable in this brief report to present an adequate discussion of the structure of this region. This will ne<(\ssarily be left

Sitbvey Of Paet: Of Matanuska Coal Fields. 135

for the detailed report. The general character of the structure is indicated in the sections on Plate IX. The coal-bearing rocks, Uke most of the other rocks of this region, have been strongly folded so that steep dips and complex structures are present throughout most of the area. In places there is a continued uniform dip for considerable distances, as is shown in section A-A', Plate IX, but it is not known whether this condition means simple monochnal structure or a repetition of parallel fault blocks. At other places there are frequent reversals of dip, but these may be due either to simple folding or to more complex faulting. In each of these cases the lack of definite knowledge concerning the type of structure is due to the absence of recognized characteristic strata from the distribution of which the actual structural details could be inferred.

In two areas within the field the type of structure is known with a fair degree of certainty. These areas are the ones occupied by the conglomerate in the vicinity of Castle Mountain and of Wishbone Hill. Here the clearly defined contacts of the conglomerate with the adjacent rocks, as well as the numerous individual beds of conglomerate, make it possible to determine the actual structural details.

The western end of Castle Mountain (see section B-B', PI. IX) is a monochnal block having a dip of about 6° to 20° NE. The eastern end (shown in section A-A', PI. IX) is a syncline having a broad southern limb on which the dips range from 10° to 20° N. and a narrow, sharply upturned northern Umb with dips of 60° to 90°. Possibly the northern limb of this syncUne is cut off in the western part of the mountains by a fault, or on the other hand the structure may be dominantly monochnal with local upturning of the strata along the fault in the eastern but not in the western part of the mountain.

Wishbone Hill is in general structurally similar to Castle Mountain. The eastern end (shown in section D-D', PL IX) is a syncline pitching sharply toward the west. The western end is Ukewise synclinal, but the northern limb of the syncline has been cut by a fault in the western end of the hill and in the valley of Moose Creek, as is shown in section E-E', Plate IX, so that the conglomerate mass as exposed on Moose Creek shows dominant northward dip and but for a few exposures showing gentle southward dip would appear to be a monochnal block.

The points of dissimilarity between Castle Mountain and Wishbone Hill are that on Castle Mountain the entire northern edge is bounded by a fault which has brought the arkosic rocks beneath the coal into contact with the conglomerate above the coal, whereas on Wishbone Hill the fault is possibly absent at the east end so that the coalbearing rocks encircle the end of the conglomerate mass, and at the west end the fault is not of sufficient magnitude to bring more than the. coal-bearing rocks into contact with the conglomerate. The

136 Mineral. Resoubces Of Alaska, 1910.

synclin© at the east end of Castle Mountain pitches toward the east, whereas tlie one at the east end of Wishbone Hill pitches toward the west.

Both Castle Mountain and Wislibone Hill are of fairly simple stnicture, so that if the coal beds persist beneatli tlie conglomerate, and if the coal-bearing rocks were not folded before tlie conglomerate was hiid down, mining sliould be simple, at least as far as structural conditions are concerned.

It may perhaps be considered probable that the structures of the entire valley are of the same general type as those known in the areas of tlio conglomerate. If this is tJie case, there are probably large areas in which stnictural conditions will permit the mining of the coal. This condition can not, however, be definitely assumed to exist, and the character of the stnicture must be regarded as a problem to be solved by imderground exploration before the feasibility of mining at a profit the coal of any particular tract can be deinonstnitod.

Effect Of Intrusive Rocks.

Intnisive rocks are present in abundance and in large masses tliroughout the greater part of the area of coal-bearing rocks except in tlie valleys of Moose and Eska creeks, where they are small and are much less numerous than farther east. The areal distribiltion of tlieljirjrcTof tliose intrusive masses is indicated on the map (PI. VIII). Small dikes and sills, not ro|)resented on the map, are also present thronghoiit iractically all the coal areas. Where tlie intrusives cut the coal hods the coal is rendered worthless for a distance of a few inciies from the contact . The small dikes and sills, on accoimt of the siiort distance to which their elFtM-t extends, would not affect the coal seriously, exco|)t that th( sills siiow a habit of seeking coal beds for their |)lanes of intrusion. It is clear tiiat if a sill is intnuled into a coal bed for a long distance a large amount of wortidess coal 411 result, wiiereas if it is intruded between rock strata, even if onh' a few feet awav from tiie coal bed, or if it cuts across the coal bed in the form of a dike, its effect on the coal will he slight.

The larger intrusive nuusses are of nnicii more serious importance than the small dikes and sills, fii'st, tiieir size is sufficient to reduce the coal areas verv considerablv, and, second, because each of them is likely to have sent olF uuiny apophyses in the form of sills in or along the sui-faces of coal beds. The dimensions of these masses are, moreover, probably greater beneath the surface of the ground than at the surface. There may also be many intrusive masses which do not outcroj) but which are near enough to the surface to be encountered in mining.

Bulletin 480 Plate

Stjbvey Of Part Of Matanuska. Coal Fields. 137

In conclusion, it must be stated tliat the presence of intrusive rocks in the coal field introduces factors which make an undetermined percentage of the coal areas of very doubtful value. The actual size and distribution of these intrusive masses beneath the surface, as well as at the surface in the areas of scanty outcrops, can not be determined without underground exploration. The effect of the smaller intrusive masses on the coal depends on the extent to which these have been intruded into or on the surfaces of coal beds. Where the intrusive mass is in actual contact with the coal the coal is worthless, but where it is a few feet away the quality of the coal is probably unimpaired or even may be possibly improved.

Chabacter Of The Coal.

The physical and chemical properties of the coal have been fully discussed in previous publications. This discussion will not be repeated in detail here. It is suflBcient to state that the coal on Chickaloon and Bangs rivers and on Coal Creek is high-grade bituminous and is probably at least in part coking coal, whereas that in the western end of the district, namely, on Moose, Eska, and Young creeks, is low-grade bituminous and is probably all noncoking coal. The anthracite described in earlier publications is not known within the area here described but Ues farther east.

The following table includes characteristic analyses from different parts of the area. The analysis of sample No. 11382F was taken during the investigations here described. The other analyses have been published in Bulletins 289 and 327 and represent samples collected in 1905. All the samples except Nos. 2215 and 2227 are from surface prospects or from outcrops and are consequently somewhat weathered. Samples 2215 and 2227 are from a tunnel at a distance of 43 to 58 feet from the mouth and probably under about 25 or 30 feet of cover.

I Martin, G. C, A reconnaissance of the Matanuska coal field, Alaska: Bull. U. S. Geol. Suney No. 289, 190t>, pp. 18-19, 26-3Q. Paige, Sidney, and Knopf, Adolph, Geologic reconnaissance in the MataniLska and Talkeetna basins, Alaska: Bull. U. S. Geol. Survey No. 327, 1907, pp. 52-56, 59-62.

riSERAI, RESOURCES OF ALASKA, lOlO.

H

S

Si is

isiia

: I ifiU

mm I

A Reconnaissance Of The Willow Creek Gold

Region.

By Frank J. Katz.

Introduction.

Placer prospects were found in the Willow Creek region in 1898. Up to 1906 efforts seem to have been directed mainly to the development of the placers of Grubstake Gulch and Willow Creek. So far as the writer has been able to find out the first quartz-lode location was made in 1906 on the ridge between Willow Creek and Fishhook Creek. This was followed in 1907 by other locations on Fishhook and Willow creeks. In 1908 the field was extended on the west by locations on Craigie Creek, and in 1909 by locations to the north and east of Fishhook Creek, around the head basins of Archangel Creek, and on the moimtain between that creek and Little Susitna River. Altogether some 60 claims are being developed and several other prospects have been located.

In September, 1906, Paige and Sargent, of the Geological Survey, visited WUlow Creek in the course of a general reconnaissance of the Talkeetna region. Paige's descriptions of the geology and placer mining were published in 1907.* In September, 1910, after finishing the season's work with G. C. Martin in the Matanuska coal field, the writer, accompanied by Theodore Chapin, spent four days in the Willow Creek region. The observations made and the information collected by them are embodied in this report.

Geographt.

Locatian and area. — The Willow Creek gold field is included in an area 10 miles square which Ues in about longitude 149° 20' west and latitude 61° 50' north. It is approximately 20 miles northeast of Knik, a settlement on Ejiik Arm of Cook Inlet. The field occupies the southwestern part of the Talkeetna Range.

Pal0, Sidney, and Knopf, Adolph, Reoonnalssance In the Matanuska and Talkeetna basins, with notes on the plaoen of the adjacent ngion: Bull. U. 8. Oeol. Survey No. 314, 1907, pp. 104-125; Oeologio recon- In the llatafniilra and Talkeetna basins, Alaska: BulL U. 8. Oeol. Survey No. 327, 1907.

140 Mineral Resources Of Alaska, 1910.

Topography and (Irainaqe, — The region comprises the divide between Lith Susitna River and tlie soutli fork of Willow CYeek and is chvisiblo into a northern and a southern part. The northern part is a higli, rough moiuitain mass, wliose 6,000-foot siinmiit is sometimes locally spoken of as '*tlie Pinnacle," from which radiate the headwaters of Willow (Yeek and the western tributaries of Little Suedtna River. The southen) portion is a somewhat lower and less rugged ridge, called Bald Mountain, lying between the lower courses of Willow Creek and Little Susitna River.

From tlie central northern mountain Purches Creek, Cndgie Creek, and tlie creek known as the **head of Willow Creek" flow west, southwest, and south-southwest, respectively, to Willow Creek. Fair Angel Creek and Fishhook (Yeek head against the same mountain and flow southeast and south, respectively, to Little Susitna River. little Susitna River flows south along the eastern part of the region to the Matanuska Valley and turns west, following the base of Bald Mountain and receiving from it many small tributaries.

The important streams of the northern part of the district are Ai-change Creek, with its branches, and Fishliook Creek, wliich are tributary to Little Susitna River, and Craigie Creek, the "head of Willow Creek," Gnibstako Gulch, and Wet Gulch, tributary to Willow Crock. Archangel Creek is a westerly tributary of Little vSusitna Kivor. Alunit miles above the river it forks. The nortliorn hranch is known as Rocd Crook and the eastern as Fair Anjrol Cn'k. Fair loads in several oir(|ues on the east and nortlioast side of ''tlio Pinnacle." It is 2] miles long and has ii soutlieaslorly course. Its basin is U-shaped and from 2,400 feet to ,3,400 in altitude. Fishhook Crook is south and west of Fair Crook. It flows south about 3 niilos from a large compound oir(|Uo on Iho soutli of "tlio Pinnacle" and then bonds sharply east to liittU' Susitna Kivor. It a U-sliapod basin from 2,000 feet to 4,000 fcM't and about 300 foot above Little Susitna River. Th( '' luad of Willow Crook'' is west of Fisldiook Creek and occupies a glacial trough 3,000 to 4,000 foot liigli and about 2 miles long. It flows southwest to Willow Creek (south fork) proper, which flows w?st. Craigio Crook has a U-shapod valloy of the head of Crook. Its basin is from 2,500 to 3,500 foot high and about 51 miles long, directed toward the southw-ost. It hangs about 400 feet above Willow Oook.

The ridges between these streams are narrow, high, and nigged, \vith steep, cragg} upper slopes. Between the head cirques are very sharp aretes.

In the southern part of the district the important streams besides Willow Crook and Little Susitna River are those in Grubstake Gulch and Wet Gulch, tributaries of Willow Creek. These gulches are gla-

Reconnaissance Of Wiixow Creek Gold Region. 141

ciatecl basins about 3 miles long, heading against the north side of the summit of Bald Mountain. There are four minor streams on the north side and a dozen or more small gulches on the south side of tliis ridge.

Climate. — There are no recorded observations on the climate of Willow Greek region. It may be said, however, that conditions are in general the same as in the lower Matanuska and Susitna basins, with perhaps a slightly heavier precipitation and shorter summer. In 1910 snow lay on some of the prospects at high altitudes, delaying development work imtil August.

supply, — There is httle perennial snow in the district, yet considerable ice persists in the broken rock and talus of the higher mountains. From these sources the streams in the northern part of the region were kept high enough during the dry 1910 season to run such small mills as have been erected. Craigie, Willow, Fishhook, and Fair Angel creeks appear to have during the summer sufficient volume and fall to run prospecting and small development mills for the claims located on them. Large power development is possible at the canyon of Little Suflltna River, which is less than 10 miles from the farthest prospect.

For the hydraulic placer mining on Grubstake Gulch the creek has in ordinary years furnished ample water, in rainy years more than could be handled, but in an exceptionally dry season it has failed.

Timber. — In the .Willow Creek basin there are no trees above the mouth of Grubstake Gulch and no good spruce above the mouth of Wet Gulch. On Little Susitna River good spruce is about a mile below the mouth of Fishhook Creek. The lumber supply is plentiful and good in the lower parts of the Willow Creek and Little Susitna River valleys. The heads of the streams at the prospects are devoid of alders and willows. Tlie gold-quartz prospects are 4 to 8 miles from building and mine timbers, and even brush for fuel must be hauled or packed at least half that distance.

The Matanuska coal field, which is 25 to 50 miles by trail from the Willow Creek prospects, has furnished forge coal and is a source of fuel for the region. Lignite is reported nearer by, on lower Willow CVeek.

Routes. — There are three routes from Knik to the Willow Creek district. One trail which is used only in the winter goes north from Knik around the western end of Bald Mountain to and uj) Willow Creek. By this route it is about 30 miles to the mouth of Craigie Creek. The old summer trail to Willow Creek takes a northeasterly direction through Cottonwood to Bald Mountain, crosses Bald Mountain at an altitude of 3,400 feet, and goes down Wet Gulch to Willow

Martin. O. C. RtconnftJawMioe of the Matanuska ooal field, Alaska, In 1905: Bull. U. S. Geol. Survey No. 280, 1906 pp. 7-8.

142 Mineral Resources Of Alaska, 1910.

Creek. This route is about 26 miles. The third route is a fair wagon road which can be used throughout the year. It leaves the winter trail near Knik and strikes northeasterly across the lowlands to Little Susitna River. It crosses to the west bank and follows up the river to the mouth of Fishhook Creek. The distance is 28 miles. The usual route traveled from Knik to Fishhook Creek in" sunmier follows the old Willow Creek summer trail to the wagon road and then the wagon road. There are trails from Willow Creek at Wet Gulch to and up Craie Creek, to Grubstake Gulch, and up to the of Willow Creek. From the head of Willow Creek a trail crosses the divide between Willow and Fishhook creeks through a saddle somewhat lower than 4,000 feet. From the mouth of Fishhook Creek trails lead up Fishhook and to the head of Fair Angel

Creek.

The distribution of the rocks, which is shown on the accompanying sketch map (fig. 18), may be summarized as follows:

A line drawn west from the pass between Willow and Fishhook creeks and along the north side of Willow Creek marks the contact of a large area of quartz diorite on the north and mica schists on the south. North of Willow Creek the country rock, which is locally called granite, is light colored, of granitic texture, and composed of feldspar (cliiefly phigioclase), quartz, hornblende, and biotite. It is uniform in composition and texture. Quartz diorite is scientificrtlly a more name for tlio rock than granite. There are a very few ba,saltic (diabase?) and aplitic dikes of small size cutting the quartz diorite. South of the quartz diorite as far as the summit of Bald Mountiiin and of Little Susitna River the rocks are tliorouhly foliated mica schists. Tlie scliistosity has a prevailingly southward dip. Quartz stringers are commonly seen in these scliists. On tlie soiitli flanks of Bald Mountain and the mountain opposite it ea.st of Little Susitna River are Tertiary arkoses, sandstones, and shales. iVlong the northern limit of the Tertiary area some of the arkosas, which are sedimentary rocks composed of disintrated granitic material, so closely resemble the ijjranite or diorite adjacent to them that their differentiation in the field requires considerable care. A narrow tongue of granitic rocks ap|)ears to lie along the top of Bald Mountain between the Tertiary sediments and the schists. The Tertiary sediments lie unconformably with southerly dip on the quartz diorite east of Little Susitna River and are probably in like relationslup on Bald Mountain. The quartz diorite appears to bo intrusive into and largely to surround the schists. A small amount of basalt was noticed on the summit of Bald Mountain west of the head of Wet Gulch.

Keconnaissahce Of Wiu.Ow Creek Qold Begiox.

Z. Brooklyn DcTflppmoit On. 1. Gold duvU HhUDS Co. 4. mcOold

FIske & Herd group, BbtIIwIMihucs group, proapert. HUkr pnipMI.

Recent glacial and stream deposits are present in all the valleys. Terraced gravel benches line the lower portions of Willow Creek and Little Susitna River.

144 Mineral Resources Of Alaska, 1910.

Mineral Resources And Mining

The mineral resources of the Willow Creek region are gold placers and gold-bearing quartz lodes. In 1906 Sidney Paige, of the United States Geological Survey, spent two days on Willow Creek and in its vicinity. Descriptions of the gold placers as then developed have been published in the reports by Paige and Knopf.* The gold lodes of the region had not been examined by the Greological Survey prior to the visit upon which the present report is based. Such information as could be gathered from reliable reports of prospectors and others interested in the region was summarized and published by Brooks.

Oold Lodes. General Description.

As the writers time in the Willow Creek region was limited to four days, only the more developed prospects were visited. The following account is therefore incomplete.

The important prospects all lie north of Willow Creek in the area occupied by (luartz diorite. In tliis area there are a few small dikes of diabase and aplite. At one prospect only are dikes (aplite) intiinalely associiited witli tlie ore body. Tlie quartz diorite tliroughout the region is very much jomted. The most prominent and also tlie (loininant systems of joints, which strike N. 40® W. (dip 20® to 40° SW.) and N. 30° K. and N. 00° W. (nearly vertical), cut the rock into Jui<;e rliomboliedral blocks that form a striking feature in the topora|)]iy. At liiJier altitudes the rock does not decom- ])ose and <lisinte<:rate. Denudation a|)pears to be largely accom- ])lislied by llie <lislod<:in< of joint blocks. The quartz diorite mountains everywliere in tlie Willow Creek region and as far back as one can see into the Talkeetna Range are consecjuently marked by peculiar blocky or tilted steplike forms. Single fissure planes are traceable for long distances. Movements along these planes are Jiere and there indicated by slight crushing slickensiding and do not to be important except in so far as they opened the fissures.

The ore bodies of tlie region, witli the to be noted below, are (piartz fiUings in fissures having as a rule shar])Iy defined walls, there commonly from a small fraction of an inch to 2 or 3 inches

PaiKe, Sidney, aiui Knopf. Adolpli. ItivonnaLssanre in the Matanuska and TalkJ'etnii bojuiiut, with motes on the plai-ers of the adjiK-ent region: Bull. U. S. (Jeol. Survey No. ;U4. l'H7, pp. 11(>-118: Geologic ewnnai.ssance in the Matanuska and Talkeetna bains, .Ma.'ka: Itull. V. S. (Jt'ol. Survey No. 327, pp. 65-67.

Brooks, A. II., The mining industry in 19<>9: Bull. I'. S. Survey No. 412, 1910, pp. 3o-3t>.

' These directions are approximate only and are referred to the magnetic north, declination 28° 38' E. at ,

' Bec0Nkais8Ance Of Wii4Low Cbeek Qold Region. 145

of clayey decomposed diorite along the quartz. Many narrow quartzcemented breccias of the wall rock liave been found along or withm the veins. The quartz is white and bluish gray, in many places banded and giving evidence of having been broken and recemented along planes roughly parallel to the walls. The veins lie for the most part along fairly regular plane fissures that are persistent, so far as present developments establish absolutely, through several hundred feet, and some are reported to have been traced for several thousand feet. There are also quartz veins or stringers in irregular, less persistent small fissures which are being prospected. These veins are from 1 or 2 inches to 4 feet in thickness. The smallest one which lias been located as a "lode," so far as the writer saw them, is 16 inches thick. With few exceptions within the region proper the veins strike nearly northwest with moderate southwest dip.

There is little visible mineralization in most of the quartz. Much pure- white quartz not only assays high but will yield colors on panning. Considerable quartz with abundant visible gold has been found. Here and there on the veins of all the prospects examined minute and sparsely scattered specks of pyrite and other undetermined minerals were found. Tellurides have been reported by several of the operators. However, in none of the material seen by the writer was the supposed telluride mineral sufficient in amount or in grains large enough to be recognized. The surface material is all very slightly porous and rusty. The Geological Survey has made no assay of these ores. The gold content of these veins, as indicated by mill tests and assays reported by the prospectors and owners, is very higli. The superintendent of the Gold BulUon Co.'s plant reports $35,375.54 received from 226 tons. Most of this was free-milling gold. High values are reported in concentrates and tailings. Reports of assays of individual samples from other prospects indicate values between $30 and $40 a ton and higher, and all are free milling. All the material thus far examined is from the surface or from points less than 150 feet from tlie entrance of the adits.

The foregoing discussion appUes to the quartz diorite area where quartz lodes are being developed. In the adjoining srliist area, particularly on Grubstake Gulch, are gold Concerning the origin of the placer gold, Knopf and Paige in the reports cited state:

The origin of the gold may be atfcribed with certainty to the abundant quartz fltringere in the mica schiHtH. The coarsenetH and roughnei of the gold HUggent a near Hource of supply. ♦ ♦ ♦ The fact that placer gold has not been found in quantities where streams have headed in granitic or other crystalline rocks bears out this statement.

Recent developments have thrown no light on this problem. It Ls

still true that there are no paying placers in the area of granitic rocks

-which contains the quartz lodes of the region, but the valleys of

96319''— BuU. 480—11 10

146 Mineral Resources Of Alaska, 101O.

that area are heavily}' strewn with coarse glacial debris, are farther from tiiuber than Grubstake Gulch and hence are not attractive to the placer miner; furthermore, the prospectors' attention has been concentrated on the lodes. The writer, however, believes that the above quotation ascribes the origin of the placer gold to a source which is not inadequate.

It appears, then, that besides the occurrence of gold in the diorite in veins, large and persistent enough to make workable lodes, gold may als:) occur in the scliist in rather widely distributed small bodies which yield placers.

Description Of The Prospects.

Craigie Creek. — The Gold Bullion Mining Co. is developing a group of five claims near the summit of the ridge on the south side of Craigie Creek about 5 miles from the mouth of the creek. The lode lies at an altitude of about 4,500 feet, or roughly 1,500 feet above the valley bottom. The mountain slope below the prospect is mantled by glacial debris and talus which contains a great deal of vein quartz in large and small pieces. At and above the prospect there is some talus and the bedrock Ls considerably disrupted, disturbed, and loosened by weathering (chiefly frost heave). The development work has consisted largely of cleaning out the loosened surface material in order to imcover the lode iji firm bedrock. The quartz sorted out in this work hits the lartjer j).irt of the '*ore" handled. a distance of 3,000 feet several patches of gold-bearing quartz have been encoiintiTed. The vein or veins are about 2 feet to feet thick. cuts and a short adit have been made Avliich show such veins, but all of these were more or less obscured at the time of the visit. A breakdown of the aerial tram had stopped work for ah:)ut a month and tlio had been permitted to become covered bv It seems that the openings are along a single vein or vehi zone whose outcrop has an east-west (magnetic) trend and low dip to the south, but this has not been definitely established by the workings.

The ore is quartz in whicli a little free gold and small specks of sul|)]sides are visible. The quartz is dominantly white but in some places sHghtly rusty and in othei*s hluisli. In some pieces quartz diorite was seen " frozen '' to the quartz, but in general both the quartz and the quartz diorite are cruslied and seamcvl parallel to the walls and there is some slickensiding and gouge along the walls.

The Gold Bulhon Mining Co. has erected a 2-stamp) mill, capacity about 0 tons a day. The mill is run by water power, amply sufficient for five more which the company intends to install during the winter of 1910-11. A light aerial tram was used to bring the ore down over the high steeper slope of the mountain, below

Beconnaissance Of Willow Greek Gold Region. 147

which the ore was dragged m stone boats for about 100 yards by horses. All wood for building, timbering, and fuel miist be either dragged or packed by horses from at least 6 miles below the mill.

Willow Creek. — The Brooklyn Development Co. has 11 clahns in and around the basin at the head of Willow Creek. Development work has been conjGjied to one of the claims near the summit of the ridge on the east side of the basin. Here there are three small cuts and an adit 150 feet long. The quartz diorite is much broken up by joints striking from N. W. to N. W. with dips southeast from 23° to nearly vertical. Along the fractures the quartz diorite is much crushed and weathered to clay. Quartz lenses and stringers of small size were seen in the fractured quartz diorite shown in the cuts and in the adit. On the dump at the adit larger chunks of quartz indicated that a vein had been cut (probably near the entrance and now covered by timbering so that it was not seen). This quartz is rusty and shows small scattered specks of pyrite and galena (?). It is reported that the adit was started on a vein with low dip which carried it above the adit. At a number of points along the adit the quartz diorite is fractured, crushed, and much decayed. There are - small quartz veins in these fractured parts. The reported values are high.

Fishhook Creek. — The Alaska Gold Quartz Mining Co. operates a group of claims, locally known as the Carle prospect, on the Fishhook Creek side of the ridge between Willow and Fishhook creeks about 3J miles above the mouth of Fishhook Creek. The prospect is on the steep wall of a small cirque several hundred feet above the level of the main valley floor. The prospect is a quartz vein which has been exposed by stripping the dfibris along the face of the mountain through 300 or 400 feet. An adit has been driven 150 feet on the vein.

The vein strikes approximately N. 52° W. (magnetic) and dips 24° SW. It is not perfectly plane and its thickness is slightly variable but averages about 2 feet. At 147 feet from the entrance the vein is broken by a dip fault of large hade and 4-foot throw.

The quartz is in part banded, white, gray, and dark bluish, carrying scattered minute sulphides ( ?), and in part very white, massive, and free from visible mineralization. The walls are sharply defined and generally smooth, with a gouge or clay from a small fraction of an inch to 2 and 3 inches thick. Along the borders of the vein are numerous angular fragments of granite, commonly very much decomposed, included within the vein filling.

All parts of this vein are reliably reported to yield free gold by

Panning.

Besides stripping between 300 and 400 feet along the outcrop and driving an adit 150 feet on the vein, the company has put up.

148 Mineral Resources Of Alaska, 1910.

on Fislihook Creek, a small water-power 2-stamp proepecting mill without concentrators and has built a trail over the steep mountain face between the prospect and the mill.

Adjoining the Carle prospect on the south and the Brooklyn Development Co.'s property on the east is the Thomas prospect. This is by the Free Gold Mining Co. At about the same altitude as the Carle a vein of quartz has been stripped for 500 feet or so along its outcrop. The vein, which strikes N. 40® W. (magnetic) and dips 36® SW., has been entered by a slope adit. This was partly filled with water, so that only the upper part of the could be seen by the writer. The vein is about 16 inches thick and in every way similar in ap|)earance to that on the Carle prospect, of which it may bo an extension.

Besides the Carle and the Thomas prospects on Fishhook Creek there are several others which were not visited by the Survey party. Quartz from which gold can be obtained by panning has been found all around the Fishhook basin. On the divide between Fislihook and Fair Angel creeks the Reed & Fiske claims have been located. A large number of open cuts on this property indicate a quartz vein continuous for 300 feet, averaging 4 feet wide. The vein in some places includes a granite breccia and has gouge or clay along the walls. The strike is N. 40® W. (magnetic) ; the dip 30® SW.

Fair Angel Creek. — Tlio Matanuska Gold Mining Co. has b:un work on a group of four claims near tlic lioad of Fair Angel Creek. Tlie prospect is near the top of a steep circine wall and is at an altitude of about 4,500 feet, wliich is 1,500 feet above the camp in the valley bottom. In the neijjjliborliood of the prospect aplitic dikes were seen in the 'ranite.' The "vein'' is an aplitic or pegmatitic dike, in places 9 feet thick, striking N. ()()° W. (magnetic) and <li|)- ping 52® XE. Tliis rock is a whitish or pinkisli quartz-feldspar rock, witli a few scattered black minerals, liornbende, and apparently also tourmaline. Tlie dike has been shattered and by (juartz, especially along the wall, wliero there is locally 8 indies of vein quartz. Between tliis and tlie granite is a narrow gouge seam. The values appear to be associated with the vein quartz, in which small specks of sulphide minerals are visible. The granite wall is everjwhero more or less decayed and is said to cany

values.

Two small open cuts wore made on the "vein*' during 1910. A tunnel was to be driven during the winter of 1910-11.

The Ccmro}' claims adjoin the Matanuska Gold Mining Co.'s property on the north. Tlie prospects lie on a ridge separated from those of the Matanuska Gold Mining Co. by a small cirque. There has been no work done on these claims except a little stripping of loose rock from the vein or veins at several places. At one such place

Begonkaissance Of Willow Greek Gold Region. 149

the amount of quartz exposed is small. At another the indicated strike is N. 40° W. (magnetic) and the dip southwest. In attitude of the vein and appearance of the quartz this prospect corresponds with the commoner type of the district and not with the adjoining Matanuska Gold Mining Co.'s prospect, which is exceptional.

OuUying prospects. — Some claims have been located outside of the main quartz diorite area. Among them are the following:

The Lydell claim is in the pass between Willow and Fishliook creeks, on the contact of the quartz diorite and the mica schists. This claim was not visited by the Survey party. However, from reliable sources it was learned that there is a large quartz vein along the contact and a number of smaller quartz stringers in the schist. So far as at present known there are no important mineral values in this prospect.

The MiUer claims are in the Little Susitna River valley. One on the east bank is about 2 miles below the mouth of Fishhook Creek. There is here a mass of quartz between 60 and 80 feet tliick; the upper wall is brecciated and much-altered quartz diorite ( ?). The lower wall was not exposed. The trend of the quartz mass appears to be N. 20° W. (magnetic) and it is either vertical or dips about 28° SW. The locator is engaged in crosscutting the quartz. The 'ore" is bluishwhite fine granular quartz with sparsely scattered pyrite crystals. So far as known the ore carries no gold values. The occurrence is most probably a quartz-fiUed brecciated fault zone. It is said to be traceable for 3 ihiles along Little Susitna River.

Mr. Miller has another claim on the west side of Little Susitna River about 3 miles below Fishhook Creek. This was not visited and no satisfactory information about it was obtained.

Suggestions For Further Prospecting.

The prospects thus far located around the heads of Craigie, Willow, Fishhook, and Fair Angel creeks are all high on the cirque walls or narrow ridges between cirques. There seem to be two reasons for tliis restriction in area and altitude. First, the prospecting has been limited to the region nearest to and most readily accessible from the supply point, Knik. Second, the lower slopes and creek basins have been mantled by glacial d6bris, talus, and moss, which make the surface-examinatiipi method of prospecting practiced in the district impossible at lower altitudes. The ridge crests on wliich tlie prospects are located have been exhumed by glaciation from considerable depths, and it is probable that the phenomena of fracturing and veining thus exposed are present at lower altitudes also. The wide extent and persistent character of the joint systems, so strikingly apparent in the surrounding mountains of the same country rock.

150 Mineral Resources Of Alaska, 1010.

suggest tliat some of the veins associated with the joints may also have as wide a distribution, both areally and at lower levels, and that at a given locality there may be veins at several elevations. For these reasons, and because the veins are not steeply inclined, prospecting by drilling and sinking shafts appears advisable.

Oold Placebs.

The placers arc on Grubstake Gulch and on Willow Creek below Grubstake Gulch, both along the creek and on a bench on the south side (left limit) of the creek. Placer gold has been mined in commercial quantities at only one locality within the ron — that is, on Grubstake Gulch. Willow Creek proper was staked by M. J. Morris and L. Herndon in 1898, and it is reported that thej extracted about $4,000. In 1899 A. Gilbert staked Grubstake Gulch, and in 1900 he sold his interest to O. G. Herning, who manages tlie property for the Klondike Boston Mining Co., of Boston, Mass. This company also controls ground on Willow (Veek and a bench below Grubstake Gulch. W. E. and E. H. Bartholf own most of the other claims on Willow Creek near Wet Gulch and below.

Grubstake Gulch is a gla<*iated hanging valley tributary to Willow Creek. Near itvS mouth a rim of bedrock crosses the channel and is cut through by the present stream, which falls precipitously for about 150 foot in a very short distance and ontei-s Willow Creek at low iVii excellent dump for hydraulicking is thus afforded. The boclrock is a mica schist penetrated by small veiidets of quartz, both a<'r()ss and paraUcl to the schist osity. Tlie parallel veinlets or lenses are the more abundant. Some of them have a ])egmatitic aspect, but this could not he established in the rusty, weathered field specimens. The schistosityon tlie gulch has a strike about N. 60° E. (magnetic) and a di]) of iO"" N. The direction and inclination of the beds across the stream and tlie di|) downstream are especially favorable for the collection of any gold that have been <'concentrated from the rocks in the ])rocess of erosion.

Minin]: was begun above the falls. In tlie years 1904 to 1909, during wliich hydraulic methods liave been in use, 1,200 feet of the creek with an avenige width of 200 feet and a de|)tli from 2i to 9 feet and locally (on the terrace on the west side) 12 feet have been worked out. The bedrock slope is about 1 to 24, or Hume grade (6 inches to the 12-foot box). About one-tliird of the gold is coarse and rough, averaging one-tenth incli in diameter; tlie balance is moderately line. The gold assays at the mint $16.58 an ounce. Very Uttle black sand is found. In the lowest portion of the pay streak the gold was on a clay above bedrock, but higher u[) tlie creek the clay was absent. The greater part of the gold occui-s close to or in crevices

Begonnaissancb Of Willow Creek Gold Region. 151

of the bedrock, but it is not deemed necessary to clean up by hand, the hydraulic giant being relied on to sweep all the gold into the boxes.

The wash, which is confined to the gulch bed — there being no bedrock bench, although the terraced surface of the gravels is spoken of as a bench — is coarse, ill sorted, and not greatly waterwom. The many large bowlders make it necessary to employ two men in breaking up and removing oversize and add materially to the cost of extraction. Three Hendy giants are installed on the property, two No. 2 and one No. 1 . The No. 1 is not ordinarily used. Seven hundred inches of water with a head of 180 feet is brought threefourths of a mile down the gulch. A 24-inch pipe at the intake dam is reduced to 9 inches at the giant, to which is fitted a 3-inch nozzle. Twelve hundred feet of sluice boxes have been built. These are 27 inches wide, 30 inches deep, with bottom boards 1 J inches thick and side boards 1 inch thick; the frames are 3-inch square timbers. Block rifHes are used. The gravel is driven to the boxes by the giants, at least one of which is directed across the creek — that is, parallel to the bedrock crevices. Very little gold is caught below the fourth box, the greater part being retained in the second. Mercury is placed in the third, fourth, and fifth boxes.

During 1910 the Grubstake Gulch operators limited their work to the extension of their pipe line about one-fourth mile and making other preparations for hydraulicking the bench at the mouth of Grubstake Gulch.

A ditch was built a few years ago from Wet Gulch down the south side of Willow Creek for the purpose of exploiting terrace gravels along Willow Creek. This project apparently has been abandoned.

Summary.

The Willow Creek region is an area about 1 0 miles square some 20 miles northeast of Knik, on Knik Arm of Cook Inlet, Alaska. It includes an area of quartz diorite which is intrusive into and surrounds a belt of mica schist in its southern part and which is overlapped by Tertiary sediments along the south border of the region. The quartz diorite is cut by a few small dikes of diabase and aplite. A regular system of definite and continuous plane joints has broken the quartz diorite into blocks roughly rhombohedral in shape. There are other less regular and persistent joints, and along some of both the regular and the less regular joints there have been movements, but there are no observed faults of large displacement. Quartz filling of the fractures and decomposition of the quartz diorite along the fractures are not restricted to any set of joints, but, so far as this investigation determined, seem to be more extensive along those irregular

r

15fi MINEBAI. BESOrrtCES OF ALASKA, 1910.

frm'lui*es which are nearly vertical and trend approximately north and south, and along joints which strike approximately northwest (magnetic) and dip 20° to 40° SW, The latter is the most frequent veining and that wlii<'h is of greatest importance to the regioji. The important jirospects tlius fai- located are on such veins, which are from 16 inches to 4 feet tliick, and are demonstrably persistent through distances that warrant development. Theycarrj-smallamountsof pyrite and other minerals ami considerable free gold, much of wliich is visible in the quartz. So far as developments now show, tlie ores are free milling and high grade, and it appears not improbable that the mineral- bearing veins may be fouTid over a wider area and at lower altitudes than those now located.

Placer Mining In The Yukon-Tanana Region.

By C. E. Ellsworth and G. L. Parker.

Introduction.

It is the object of this report to give a brief summary of the general progress of placer mining in the Yukon-Tanana region during 1910. The writers were engaged in a water-supply investigation of the Fairbanks, Circle, Tenderfoot, Eagle, and Seventymile placer districts of the Yukon-Tanana region, and incidentally some notes on mining operations were made. Much of the material embodied in* this report, however, is due to information furnished by mine operators and others personally f amiUar with the conditions in the several districts.

The decrease in the value of the gold production of the Yukon- Tanana region from $10,720,000 in 1909 to $7,100,000 in 1910 can be attributed almost entirely to the drop in output from the Fairbanks mines, which in turn was due mainly to the fact that many of the richer placer deposits so far located have been worked out, although several other reasons of less importance contributed to the decrease. Every camp in the region furnished to a greater or less degree its quota of men and capital to the Iditarod district, and the increased interest taken in lode mining also drew many men away from the placers. There was also experienced in July and August the most severe drought that has occurred during that season since the beginning of water-supply investigations in this region in 1907. The successful operation of placer mines is so dependent upon the water supply that a shortage in that most important factor will inevitably result in a corresponding decreixse in goKl output.

Fairbanks District. Genebal Conditions.

The marked decrease in production in tliis district from $9,650,000 in 1908-9 to $6,100,000 in 1909-10 is due to several causes, cliief among which is the fact that many of the richest pay streaks have been worked out. New discoveries and the tracing of old pay streaks have not furmshed new ground sufficient to offset the amount worked out during the previous years. In other words, the district

a- U

154 MINKBAL BEeOl'RCES OP ALASKA, 1910.

is reihfliiiig the start; in its duvolopiiiGiit that lies the exploitation nf the rich bnimnzas and tlie installation of machinery fnrlaiscale operationa which make for economy in extracting the gold from the gravels, Tliia period of decline is experienced by most placer camps, and the interval of lower pniduction will be long or short according to the difficiilties met in making a thorough investigation of conditions and in pvrfectmg organizations for tlie purpose of applying equipment best suiteii to the recovery of gohi from gravels caiT>"ing low values. The exodus of men and macliinerj' lo tlie now Iditarod country also operated to cut down tiie annual output of the district, for many experienced miners transferred tlieir funds and personal attention to the new pUoer camp. It was estimated that 1 ,000 men followed the ice down the Yukon to the new strike and, although many returned later, a disquieting efCect was\ produced which was felt throughout the season.

The scarcity of water for sluicing necessitated the closing down nf a nimiber of plants and a reduction of the force employed at many others. The data secured during the summer at anumber of stations i on streams in the district (see p. 181) indicate a relatively lower run-off during Jidy and August than has been recorded for any year since stream-flow investigations were begun in tliis section, in 1907, Still another reason for the decrease in the gold output may be tlio greatly increased activity in prospecting and ileveloping quartz lodes in this vicinity, wbii'h has diverted the cITorts am! capital of a considerable number of experienceii operators from placer mining.

Mining methods and conditions were practically the same as in previous years, and no great advance was effected in reducing the hi cost of working the gravels, but some steps were taken to develop dredging ground. It is estimated that in 1910 between 1,300 and 1,400 men were employed in actual placer mining in the district on about 140 claims.

Oolbstrbam Basin.

During the winter of 1909-10 antf the summer of 1910 Goldfltream Valley presented a lively scene of mining operations from a point near the head of Pedro and GiUnore creeks to "No. 17 below." Open-cut methods were used extensively in the upper portion of the vaUey, where the depth of the ground permits working in this manner. Turo laige open-cut plants, one on "No, 9 below" Pedro and the other on "No, 5 below" Goldstream, operated bottomless scrapers successfully. It is reported that the cost of working the ground was lees than 30 cents a square foot, which ia low for the Fairbanks district. Several other smaller plants operating on Pedro Creek also proved the economy of the open-cut method of mining. The usual practice of drifting and hoisting was employed exclusively on lower Goldatream

Placer Mining In Yukon-Tan Ana Begion. 155

and Engineer creeks. Probably 90 per cent of the production of the Coldstream Valley waa secured in this manner. In size the plants ranged from a hand windlass worked by 2 men to a 60-horsepower steam plant employing 40 men. Some difficulty was experienced on Engineer Creek with thawed groimd and underground water, but the most serious drawback of the season in this basin resulted from the scarcity of water for sluicing. Several of the mines working on lowgrade gravel were compelled to shut down entirely on this account, and a number of others were not able to work a full force during the low-water period.

Successful prospecting on the second tier of benches on the left side of Goldstream, opposite "No. 8 below," early in the spring led to the development of a good pay streak extending over three claims opposite "Nos. 7, 8, and 9 below'' later in the season. Considerable prospecting was done during the summer and is still being done to trace the pay gr&vel farther up and down stream. Bedrock on the second tier and creek claims is at about the same elevation, but the pay streak above the former seems to be of a uniformly higher grade than in the creek bed. The depth of ground, however, is somewhat greater on the bench claims, as the average depth of hole is between 100 and 110 feet. It is estimated that 500 men were employed in placer mining on 52 claims on Goldstream, Engineer, Pedro, and Gilmore creeks during the winter season and probably about 20 per cent more were working during the summer months.

Chatanika Biveb Basin.

Cleary Greek, — A large percentage of the annual gold production of the Fairbanks district continues to come from Cleary Creek, which has produced more gold than any other creek in the Yukon-Tanana region. The settlement of the legal status of '*Nos. 4 and 5 below'' in 1909 made it possible to resume working in the richest part of the creek. The large plant on ''No. 5 below" employed between 50 and 60 men. Practically all the claims from ''No. 10 above" to "No. 17 below" on Cleary were being worked during the winter, and in the spring there were between 40 and 50 large dumps to be sluiced with the spring run-off. The summer operations, though not so extensive on the upper portion of the creek, were of greater magnitude than those of the winter season on the lower portion. This was largely brought about by the Chatanika ditch, which furnished eight operators with all the water that was needed for sluicing. Several of the operators made use of electrical energy supplied by the Poker Creek power plant for pumping the water from the ditch to their sluice boxes set at a higher elevation.

Wolf Creek, which was prospected rather thoroughly in 1909, began to yield good returns in the spring of 1910. Both open-cut and drift-

156 MINEBill. RESOURCES OF ALASKA, 1910.

ing methods were employed in extracting the gold. . The success attained by several small outfits engaged in 'sniping" during the summer drew attention to the possibility of profitably working over the old tailings. It is conceded that the ground on Cleary Creek is of too great depth to work by hydraulic methods; but it is thought by local men that the gold remaining in the tailing piles amounts at least to 10 per cent of the quantity already recovered and that it might prove profitable to resluice the tailings with suitable ances if the water from Chatanika River could be diverted to the ground at sufficient elevation and at a cost to warrant such an undertaking.

On Cleary Creek and tributaries between 45 and 50 outfits were working on about 30 claims during the winter.

Dome Creek. — A great decrease in mining operations was shown on Dome Creek, wliieh has held a very prominent position among the producing creeks in past years. This is due chiefly to the exhaustion of the richest claims; but the fact that several of the claims are tied up in court proceedings is also an important factor. There were six or seven plants being operated between ''No. 7 above" and "No. 7 below," of wliich only two on ''Nos. 5 and 6 below" were working on a scale comparable to past operations. The extreme drought also added to the difficulties on tliis creek. It is said that there was scarcely enough water to supply a boiler on ''No. 6 below" during the low-water period, where in former seasons there was very seldom less than a sliiiee head available. Further prospecting this year "Xo. 7 below'' and ''Xo. 14 below*' has failed to locate the "lost" pay streak in this of the creek.

(liataulhi FlaU.- On lower Dome Creek, in tlie Chatanika Flats, the successful operation of a plant on the Xiggerhead group) and prospecting on the lower end of the group has defined a body of pay gravel at a depth of 1 SO feet which carries good values. Prospecting is also being (lone on the Jieconler Association claim, which is just above the Niggerhead group and up Chatanika River, on the assumption that the pay conies from the river rather than from Dome Creek. Mining was being carried on at the mouth of Vault Creek on tlie Alabama dissociation claim, and about 4 miles below this in t, near tlie mouth of Sargent Creek, gravel was being taken out from a 150-foot face which is 230 feet below the surface of the ground. The values are found on a false bedrock consisting of an impervious clay wliich is 89 feet above the real bedrock. It is thought by some of the miners that the ileveloping and that have been done along the Chatanika Flats indicate a continuous pay streak from the mouth of Cleary down to Our Creek.

Little Eldorado Creek. — It is reported tliat a 20-ounce gold nugget was found in one of the clean-ups of a plant on the Idaho group of

Placer Mining In Yukon-Tanana Region. 157

Little Eldorado Creek. Considerable money was spent in on this creek last year without adequate results.

Homestake Greek. — The shallow gravels of the tributaries at the head of Chatanika River are suited to the method of hydraulicking in vogue in the Circle district. The small hydraulic plant installed on Homestake Creek this spring was in readiness for '' piping in '' early in July, and a good showing was made, considering the drawback that was experienced through low water. The water was diverted from Homestake Creek near its head and conducted by ditch and hydraulic pipe for about 3 miles along the right side of the creek to a point near the mouth, where mining operations were begun. The head attained is 160 feei and the depth of gravel to be averages about 8 feet.

Cbipple Cbeek Basin.

Ester Creek. — Mining operations are decidedly declining on Ester Creek, which in past years has yielded a percentage of the total production in the Fairbanks district second only to Cleary Creek. This is due principally to the fact that most of the richest portions of the creek have been worked out, but the lack of sufficient water for sluicing on Ready BuUion and upper Ester during the period of drought is also a contributing cause. The scheme of winter sluicing which was mentioned in last year's report was employed by three' plants on Ready BuUion that were working in thawed ground. The plant on 3 above first tier," which operated continuously during the winter, was visited by the writers early in the spring. A brief description of this plant will be given, as it affords an example of mining by the combination of thawed-ground and winter-sluicing methods. This is an unusual practice, for either condition is thought to considerably increase the cost of working ground. A 100-foot shaft to bedrock was joined by a system of tunnels, extending parallel and perpendicular to the course of the creek, which blocked out the gravel to be worked into 50-foot squares on the bedrock level. The supports for the small spruce pole shoring used for supporting the weight of the gravel consisted of uprights about 5 feet long and caps about 6 feet long hewed from spruce timber 10 to 12 inches in diameter. These were set 4 feet apart so that the poles, which were 8 feet long, could be driven ahead as the work on the fave proceeded. It was not found practicable to pull this timbering, although the blocks farthest from the shaft were worked first and the ground was allowed to settle behind the working face. The gravel was conveyed from the. face to the bucket hoist on cars of six wheelbarrows capacity, running on rails. A 3-inch pump kept the mine drained and by turning the exhaust into the sump hole warm water was furnished for sluicing. The exhaust from the steam hoist was conducted along

r

158 Mineral Resources Of Alaska, 1910,

the bottom of the sluice boxes by use of canvas cover and aided materially in keeping the temperature above the freezing point. The Bluice water drained from the tuihng pile into a stilling reservoir and was again warmed by the exhaust from the pump, which raised it to a flume. The water was led back to the sluice boxes through this flume and was there joined by more water from the tirain pump in the mine lo begin a new circuit. No difficulty waa experienced in operating, even when the thermometer stood at 60* below zero. It is interesting to not* that the coat of working ground in this manner was claimed by the operators to be about 75 cents a square foot on a basi of weekly running expenses, not, however, taking into accoimt interest, depreciation, etc. Sixty men were employed and between 5,000 and 5,500 square feet of bedrock was worked out weekly.

Winter operations on Ester Creek proper consisted of blocking out ground for summer work and taking out dumps to be washed up in the spring. It is estimated that there were about 200 men employed on about 17 claims of Eater Creek and tributaries during the dosed season. No data are available for estimating the summer work, but it is thought that it was not nearly so extensive. The largest plant of the creek, working on "No. 3 below" and employing about 60 men, was compelled to discontinue work during the later part of the season on account of the laborers demanding $6 a day instead of the customary wages of $5 a day.

Prospecting opposite "No. 6 below," 1,500 feet to the right of the present pay streak, brought to light some very rich coarse gold prospects which are similar to the gold founti on the right side of "No. 2 below." As this gold is very unlike the finer values found in the creek claims, further prospecting is under way to determine whether there is another old channel, curving to the right, which carries this coarse gold.

St. Pairick, Emma, and Alder creeks. — Very little actual mining was done in 1010 on St. Patrick, Emma, and Alder creeks, which are small tributaries of Cripple Creek.

Fish Creek Basin!

Fairhavks Creek. — Fairbanks Oeek, though not a laie producer, has yielded a steadier annual output than any other creek in the district. Mining by both open-cut and drifting methods was carried on from "No, 10 above" to "No. 11 below." Six or seven open-cut plants were in operation, most of which employed bottomless scrapera for stripping the ground and steam hoists for carrying the gravel to the sluice boxes. On "No. 3 below" a 45-liorsepower bottomless scraper, having a capacity of cubic yards, was in use. There were a number of small operators employing a windlass for taking out the pillars and walls of gravel that were left in ground previously

Placer Mining In Yukon-Tanana Region. 159

worked by larger plants. The scarcity of water in July and August made it necessary for several of the plants to work alternately day and night, so that the total flow of the creek could be utiUzed by each plant. Winter sluicing, which has been successfully conducted during the last two years, will be employed again this winter by three of the operators. Prospecting on 11 above'' in former years had been confined chiefly to the left side of the claims, but in 1910 some very good values were obtained in holes sunk on the right side. Crosscuts were run and further prospecting carried on during the later part of the summer to determine the extent of the high-grade gravel, but it was not learned what success attended these eflForts. Summer development and prospecting has also resulted in the location of a body of gravel carrying values on claims of lower Walnut Creek and on the adjoining left-limit bench claims opposite **Nos. 1 and 2 below'' of Fairbanks Oeek. It is estimated that about 135 men were employed on 20 claims in this drainage basin during both the winter and summer seasons.

In the past there have been several large-scale plans under consideration which involved the use of a dredge for working the ground on Fairbanks Creek, and options on claims have been taken with tht end in view, but so far as knowTi nothing definite hasi been done toward putting these plans into effect. A number of owners are securing patents to their claims which insure absolute title and will simplify their relations with a dredging company, if one is organized.

Fish Creek. — decided increase in mining operations has taken place on Fish Creek during the last year, and developments this summer seem to indicate that it will remain on the productive list for some years to come. A number of operators on the upper part of the creek who took out winter dumps were very agreeably surprised when their clean-ups netted more than they were expecting. This was due largely to the presence of coarse gold, which had not been found to any great extent in prospecting. It is reported that a $43 nugget was found in the spring clean-up of ''No. 5 above/' and later in the season the operators on ''No. 2 above" are said to have taken out a nugget valued at $84.25. Previous to tliis spring it was thought that Fish Creek would produce cliiefly fine gold.

Mining was being done on almost every claim from "No. 10 above" to* "No. 2 above" by both open-cut and drifting methods. "Nos. 2 and 3 above" yielded the best returns for the summer season. Below "No. 2 above" there was some prospecting done, without success, in trying to locate a pay streak between this claim and " No. 8 below," where one outfit, employing four men, was occupied in drifting in gravel carrying fine gold. About 35 men were employed on eight claims during the winter, and it is probable that about 50 men were employed during the open season.

Inl60 UINEEAL RESOURCES OF ALASKA, 1010.

The suiTess of the smtiU liyilniuiic plaiil on Etigle Croek antt the (avX that Mammoth Creek has heen put on a produi-tive has through the satisfactory operation of the larger plant installed there (luring the summer of 1900 has given an added impetus towanl hydraulicking in this district. The character and depth of gravel and the nature of the bedrock of ]ortiona of the stream carry-ing value are favorable to this method of mining, provided sufficient water ean be liad at an effective head. The gradient of the streams, however, is not sufficient for dbposing of the taihngs without some system of stacking. A giant is used for tliis purpose in connection with the two plants mentioned above, which necessarily calls for an additional supply of water. In tliis district there are four or iive pnijccts under consideration which entail the use of water under a head for their development, and it is hoped that two of these will be in operation before the close of the season in 1911.

Tho economy attained in moving gravel liy the two plants now in operation during the extremely dry season of 1910 and at relatively high elevations lends encouragement to those who look forward to mining the low-grade gravels in the Birch Creek bars and along Preacher Creek with the considerable volume of water which would be aviiilrthle for that purpose. It shouM be borne in mimi by tiiose llie instullution of plants tbat this iHstricl embraces an area of low lun-oiT, aad ncixiniingly tiw waler supply available for each project should be carefully determined.

A renewed interest in locating new pay streaks has been brought about by the small strikes on Bottom Dollar and Fryint; Pan rrcoks, and if the summer operations on Buckley Bar of Binli Creek proper prove successful doubtless attention will be again directed to this field of endeavor.

The transportation facihties for summer traffic were not greatly improved this season on account of lack of funds. The only substantial improvement in the roads consisted of laying corduroy across the Albert Creek swamp, which separated the Government road, as completed in 1909, from the Central House. The dry weather, however, made it possible to haul larger 1oik!s over the unimproved trails from Central House to DeaJwuoil and Miller House than for a number of years in the past.

The district as a whole suffered somewhat from scarcity of labor during the fore part of the season, owing chiefly to tlio false report that there waB a great need for laborers in the I'lilrbanks distnct and that wages there had been atlvanced to $6 a day. . .

PliACEB MINING IN YUKON-TANANA REGION. 161

Cbooked Cbeek Basin.

Mastodon Creek, — A livelier scene of small-scale mining tions was presented during the summer Mastodon Creek, from ' No. 7 above" to its head, than by any other part of the district. Here the depth of gold-bearing gravels is such that the open-cut method of mining is better suited for extracting the values than winter drifting. It is estimated that 85 men were employed in this section of the creek on 12 claims through most of the summer season, though only 16 men were working on about six claims during the winter. Two of the largest operators, employing about 25 men each, made use of bottomless scrapers for removing the overburden and bringing the gravel to the boxes. On 21 above'' a water wheel furnished the power for hoisting the gravel into the sluice boxes.

The title to the claims on the lower part of the creek. from ''No. 2 below'' to "No. 7 above" has been secured by a company wliich proposes to divert water from Mastodon and Independence creeks for working the claims with small hydraulic elevators. A considerable part of this ground has been worked over during the last 10 years, but on account of the costly methods employed only the richest portions have yielded profits. The lower-grade gravels left at intervals in the creek bed and along the sides of the claims should net good returns if economical means of handUng the gravel are provided. The company landed a 300-ton outfit, consisting principally of hydraulic pipe, at Circle before the close of navigation, and if plans are fulfilled the plant will be in readiness for operating early in June, 1911. As the quantity of water is an important factor to be considered, it is thought that the use of pipe for conveying the water to the elevator pits will make it possible to begin sluicing earher in the season and that thereby a greater percentage of the s])ring run-olT may be utilized. Furthermore, the pipe can be used again in other localities under similar conditions. ''No. 6 below/' wliich six men were employed, was the only claim that was worked on the lower part of the creek.

Mammoth CreeTc. — The largest hydraulic ])lant of the Yukon- Tanana region was in operation on Mammoth Creek. Here water was diverted from Bonanza and Porcupine creeks at an elevation of about 2,350 feet and conducted to the left bank of Mammoth Creek by a ditch 10.3 miles long. The lower part of the ditch below the Bonanza intake, 6.5 miles long, was constructed in 1908 and put into good working order in 1909. A portion of the Porcupine branch of the ditch was dug in 1909 and the ground along the remainder of the ditch line was stripped of moss to allow the underlying frozen muck to thaw. Much difficulty was experienced in tliis section of the ditch last summer on account of ground ice along the steep W319**— Bull. 480-11 11

162 Minebal. Besoubces Of Atarka, 10111.

slopes near the Porcupine Intake. Wherever the ditch line crossed these pockets of nearly clear ice, the ice was kept exposed to the open air and a 'drain provided to expedite thawing. This process of thawing quickly opened up a good-sized hole in the side of the hill, and when it was possible to provide a good foundation the space below the ditch was filled in with layers of moss and dirt. This ditch was built to a grade of 5.3 feet per mile with a width of 6.5 feet on the bottom. The usual form of construction, which consists of mAlring the bottom of a ditch level, was not followed in building the upper ditch. The method adopted constitutes digging the side next to the hillside five-tenths deeper than the embankment side. When carrying water, a ditch with this cross section will have its greatest depth next to the hillside, and as the highest velocity of a stream or ditch is usually at the deepest section it is thought that the tendency of the water to cut the embankment will thus be decreased.

Operations on No. 7 below'' were carried on by the method of piping in," a detailed description of which has akeady been published. A head of 375 feet is available, but only 270 feet on bedrock was used. The completion of the Porcupine branch and the maintenance of the lower ditch kept 17 men busy during the sununer and 14 men were employed at the mine. Low water proved to be the most serious drawback to the operations of the season. Data concerning the amount of water available at each intake may be found on page 200. Since a reservoir was not provided the method of sluicing intermittently, as practiced on Eagle,- could not be employed on Mammoth. By reducing tlie size of the nozzle, however, it was found possible to work to an advantage during most of the low-water period, as only five days in July were lost through inadequate water supply. Frozen ground also offered considerable inconvenience, but doubtless the scheme adopted of stripping the gravel ahead of the pit a year in advance of operations will do much toward averting this difficulty.

Deadwood Creek. — Mining operations on Deadwood Creek during the winter of 1909 and summer of 1910, though handicapped on account of the low water, were about the same as in the previous two years. Here there seems to be no tendency toward methods leading to a reduction in the cost of extracting tlie gold. The fact that most of the damis are worked by one to three men with pick, shovel, and hand windlass as the only labor-saving devices makes it evident that ground worked at a profit bi this manner would pay well if more extensive equipment were provided. If the increased activity in hydrau licking in other parts of the district proves successful no doubt this method can be applied advantageously in worldng

1 Ellsworth, C. £., Placer mining in the Yukon-Tonaua region: Bull. U.S. Geol. Survey No. 442, 1W9, p. 237.

Placer Mining In Yukon-Tanana Region. 163

the Deadwood deposits. The water supply available for this purpose above Switch Creek is stated on page 200. During part of the season good results were obtained from the operation of an automatic dam about a mile above Discovery claim. Considerable difficulty was experienced on the upper part of the creek with the 'glacier," which formed on the claims during the winter to a depth of 15 feet in places and which did not disappear until late in July. Since there was very little water in Switch Creek after the spring thaw, operators were compelled to shut down work soon after the winter dumps had been sluiced. Information collected indicates that about 30 men were occupied in mining on 16 claus durmg the open season and that about 20 men worked 14 claims in the winter.

Independence Creek, — Mining on Independence Creek was carried on from "No. 5 below*' to "No. 13 above" by 22 men working on six claims during the summer. Winter operations consisted of eight men drifting on six claims. Pick and shovel methods are used in working the deposits during both the open and closed seasons. It is reported that eventually the lower part of the creek will be hydraulicked by the company which has gained control of the lower portion of MastodonCreek.

Miller Creek, — There were practically no mining operations -on Miller Creek during the year. The ownership of all the claims from the mouth of the creek, *'No. 7 below,'' to 'No. 21 above" has come under the control of a company which proposes to build a ditch and work the ground with methods similar to those used on Eagle Creek. As the depth to bedrock is only 6 to 7 feet at the upper end of the creek and 12 to 14 feet on the lower end, little didicultv should be encountered in stacking the tailings. Owing to the meager water supply of MUler Creek (sec p. 201) it will probably be necessary to provide a reservoir for storing the water so that it can be used intermittently during periods of drought, as is done on Eagle Creek. Ten men were employed during the later part of the summer stripping ground for a ditch, so that the large crew of men to be employed in the spring can carry the work on to completion. It is hoped that the plant will be ready to make use of the spring run-off in 1912.

North Fobk Of Birch Creek Basin.

Fxicjle Creek, — Hydraulicking on Eagle Creek was an experiment when first begun during the summer of 1908. The successful operation of the plant there during the last two seasons shown conclusively that a small outfit and a small water supply can give good results when managed properly. It is estimated that groimd carrying values as low as $1 a cubic yard can be worked to a profit with this method and under similar conditions — a fact which makes it evident that there are a number of deposits of gravel in the Circle

164 MIKKRATi RKSOUBCES OF ALASKA 1910.

district that would rondor jiood returns if this same means of exploitation could employed.

The use of a small reservoir above the Mastodon Fork intake of the ditcli made working: on a smalt scale possible even during the excessively diy period in the middle of July, when the mean daily supply delivered by the ditch was probably less than 2 second-feet (80 miner's inches). The system used involved allowing the reservoir and ditch to fdl and drawing on the storage thus supplied to operate the giants until both were emptied. It was only possible to work with about 500 miner's inches for two hours to the shift while the water was at its lowest stage. Seven men were employed to operate the plant during the summer.

Harrison CrceJc. — There were no on Harrison Creek during the last season, but it is reported that a hjdraiilicking project Ls being contemplated. Wint<?r prospecting in 1909-10 on Bottom Dollar Creek and its tributaries, Half Dollar and Two Bit Gulch, resulted in locating some good and several small dumps were taken out which netted good returns when sluiced iji the spring. It LS imderstood, however, that the pay streak was found to be narrow and the gold contained in it iri;egularly distributed. Two men worked on the cieek during the summer.

McLain Creek. — Two men were employed in operating an automatic dam on McTain Creek, which (lows into Birch Creek just above Deadman Bur, but tlie work was hampered through lack of water. If a body of gravel of sullicient extent and of sufficient gold content can be located at this point to warrant the building of ixbout 15 miles of ditch aixl to provide suitable hydraulic equipment, it is thought that an abuinlaiit water supply can be diverted from Clums Fork, which would give a working at the mouth of McLain Creek of about 200 feet. A measurement of Clums Fork at the mouth on July 25, during a medium stage, gave a discharge of 118 secondfeet (4,700 miner's inches).

Fn/ingpan Cnilc. — During the winter three prospectors located good values in a hole sunk to bedrock on the left side of Fryingpan Creek about one-half mile below the forks. The ground at this point LS about 20 feet deej), comprLsing 15 feet of overburden and 4 or 5 feet of pay gravel. A small ditch was built and prospecting continued during the summer.

Preacher Creek Basin.

The only mining done in the preacher Creek drainage basin con- sLsted of installing and operating an automatic dam on Bachelor Creek just below Costa Fork in the later |)art of the sejison. The scheme to work the Bachelor Creek gravels by the use of hjdraidic lifts, which led to expending money in partly construct-

Placeb Mining In Ytjkon-Tanana Region. 165

ing a ditch in 1909, has apparently been abandoned. It is reported that large bodies of low-grade gravel exist in the Preacher Creek valley below the mouth of Bachelor Creek which could be conveniently worked by some system of hydraulicking. A low-water measurement of 45 second-feet (1,800 miner's inches) above the mouth of Bachelor Creek seems to indicate that there is sufficient water for this purpose.

Beaveb Cbeee: Basin.

Prospects were foimd in the upper tributaries of Beaver Creek which led to the staking of considerable ground long before the Fairbanks district was developed, but no actual mining operations were carried on in that vicinity. Desultory prospecting in later years seemed to indicate that the gold content of the gravel is very irregularly distributed and that it is not extensive enough to warrant any considerable outlay of capital.

During May, 1910, some good values were found, however, on Ophir Creek, a tributary to Nome Creek, which resulted in starting a small stampede about the middle of July. All of the ground in the Nome and Trail Creek drainage basins was staked, as well as that on several other creeks near by. Systematic prospecting followed in the wake of the stampede, and if reports are to be relied upon pay streaks have been located on Nome Creek above Ophir and on Ophir Creek near its mouth. Bedrock drains were being established on upper Nome Creek during the summer by an outfit which proposes to operate a bottomless steam scraper next season. The ground is all shallow, averaging about 15 feet deep, with 2 to 4 feet of pay gravel, so that open-cut methods will no doubt prove to be the cheapest means of recovering the gold. Opiiir Creek, which flows into Nome Creek about 2 miles from its mouth, was the scene of the liveliest excitement during the stampede. On Discovery claim a 50-foot crosscut was run to determine the width of the pay streak, and it is stated that this was traced for a length of five claims before the close of the open season. The gravel carries coarse gold values at about $17 an ounce, and it is reported to run from $1.25 to $1.75 a square foot. The largest nugget found was valued at $4.30. Some very encouraging values were found on Trail Creek, which heads opposite Poker Creek, flows for about 15 miles in a nortlieasterly direction, and joins Beaver Creek about 6 miles below Nome Creek. Prospects were also found on several newly named creeks, such as Dominion Creek, Gold Moimtain Creek, and Hoosier Creek, the locations of which were not learned by the writers.

There was much complaint registered against the laws which make it possible for one man, with the power of attorney from others, to stake association claims. It is said that 12 miles of creek was staked by one man in this manner.

166 MINERAL. BE80URCB8 OF ATAftyA 1010.

Hot Sprinos District.

The value of the gold production in the Hot Springs district for 1910 is estimated to be approximately $325,000, which is the same as that estimated for 1909. The increased output from Sullivan and Cache creeks offsets the decrease from the Baker Creek mines.

It is understood that a large quantity of machinery has been shipped into the Patterson Creek basin, and the lack of capital, which has seriously retarded the proper development of the mines since the discovery of gold in this section in 1907, was not so marked during the last season as in previous years. It is reported that stream tin has been found in considerable quantities at nearly all the mines in this basin and that an investigation will be made relative to the possibility of saving that metal in connection with the recovery of the gold. It is believed, however, that the value of the presence of that metal lies in its indication that a ledge may exist, which; if located, might be worked at a profit. Sluicing in the basin opened May 10 on Tofty Oulch, where a prosperous season was reported. The overburden was groundsluiced off, and the auriferous gravel carried to the sluice boxes by a steam scraper. On Sullivan and Cache creeks new deposits of pay gravel are continually being located. Considerable difficulty has been caused by lack of sufficient sluicing water, and pumping has been resorted to on several claims in order to return the water to the head of tlie sluice after passing A few men were also mining on Quartz Creek during the summer.

On and Pioneer creeks, where open-cut methods are

used almost exclusively, a greater quantity of water is necessary for

tlie successful o})erati()n of the luhies than in those sections where

(Icep-miniug methods are practiced. The extreme drought, together

with tlie losses due to carrying the water m ditches for several miles,

caused the suspension of operations (king a greater part of the season.

On Eureka Creek claims *'No. 7 above'' to ''No. 3 below" were

vvorked by a Bagley bottomless scraper. The ground averaged about

12 feet deep and favorable results were reported, although some

difliculty must have been experienced from the prevailing scarcity of

water.

Rampart Distric T.

The estimated value of tlie gold output from the Kampart district in 1910 was $48,000, about equally divided between winter and summer production. It was less than half the estimated output for 1909, and the decrease was imdoubtedly due mainly to the fact that the richest pay streaks are about worked out, although a small decrease can be attributed to the closing down of the hydraulic plant on lloosier CVeek. It is estimated that 33 men were employed in

Piaceb Mining In Yukon-Tanana Region. 167

mining on 18 claims during the winter of 1909-10 and 42 men on 15 claims in the sunmier of 1910. The chief development in the district during the past season was the introduction of a steam-shovel plant on Hunter Creek which was in operation near Discoveiy. Little Minook continues to be the chief producer and Hunter Creek comes second in output. Quail Creek takes third place, showing a larger production than for any year in the past, and if economical mining methods are introduced the creek promises to be one of the chief producers of the district. Some mining was also done on Little Minook Junior, Slate, Hoosier, and Big Minook creeks. It is that good prospects have been found on Hosiana Creek and in the fall of 1910 about 50 men were prospecting in the vicinity.

Salcha-Tenderfoot District.

Tenderfoot Creek. — Renewed activity in mining operations on Tenderfoot Creek resulted from the location of good pay on bench claims opposite **Nos. 6 to 9 below.*' The appearance of the schist bedrock and the character of the wash indicate a higher channel which carries coarser gold than that found in the creek claims. Since the depth of the ground on this creek varies from 30 feet at 1 below'' to 180 feet af No. 17 below" only drifting methods can be used for extracting the values. Small outfits were distributed rather irregularly along the creek from 'No. 1 above" to *'No. 14 below" and mining was being carried on during both the open and the closed season. The summer operations were greatly handicapped, however, through scarcity of water for sluicing. On an average between 25 and 30 men were employed on 10 claims throughout the

year.

Banner Creelc. — Very little mining was done on Banner Creek proper during the year, but work w as done on Democrat Creek, an upper tributary. The production of "Nos. 1 and 2 above" Democrat Creek represents a very large percentage of the total output of the creek. The depth of ground on these claims permits the use of open-cut methods. Two small outfits were also mining on Buckeye Creek.

Salcha River tributaries. — Actual mining operations in tlie upper Salcha basin were confined to No Grul) and Caribou creeks. It is understood that very good returns resulted from the season's work in spite of the dilliculties encountered in this section due to thawed ground and underground water. It is estimated that 20 men were employed in mining on about five claims. Seven men were in prospecting on Twenty mile and Butte creeks and about 10 men busied themselves in hunting pay gravel farther toward the head of Salcha River.

168 MINERAL RESOUKCES OP ALASKA, 191jO,

Fortymile District. General Conditions.

Althoujrh no investigations have been carried on in the Fortyniile district prior to 1910, it is believed that the stream flow for the siimnier reached an extremely low stage, and the decrease in the value of the gold output from $225,000 in 1909 to $200,000 in 1910 can be attributed almost entirely to the inadequate sup[)ly of water for mining. No new developments were introduced during 1910, and the mining methods used were practically the same as have been in vogue for several years. The possibiUties of economically recovering the gold by means of dredges have been seriously studied, and since 1907 live different dredges have been installed on Fortymile River and its tributaries. The experience derived from their should be of value to those contemplating the introduction of such methods elsewhere m the Yukon- Tanana region, where conditions in a general way are very similar. Perhaps as a whole thoy have not proved to be a financifiJ success, and sufficient infonnation is not available to determine the reasons for the failures which have occurred. It is probable, however, that failures are in a large measure directly to lack of thorough prospecting on the of the promoter to determine the gold content of the ground. The value of tliorough prospectmg by those vitally interested can not bo too niucli for it shows not only the value* of the gohl that can he obtained from the unit quantities of gravel to he mined hut also the suitability of the ground for dredgiiig. No hydniulie development of any magnitude has been instituted in this district, hut it seems reasonable to predict that eventually such means will he to a considerable extent. It is hoped that the investigations relative to tlu* 'which are being carried on in the (iistrict will prove of value in considering the feasibility of the several projects and that failures due to a lack of suflicient water niav he largelv eliminated hv such infonnation. A summary of the streani-llow data gatherecl in this district during 1910 can found on ])ages 202-200.

Mining Operations.

WaU'ir Fork. -The dredge on Walked- Fork near Poker Creek had an exceptionally season. Some trouble was encountered during the earlier part of the sununer in frozen ground and steam points were us((l to thaw ahead of the dredge, hut it is that after the middle of July no furtlHM* diflicuhies were experienced in that respect. A gang of men was at work stripping the ground that will be worked another season, and it expected that by so doing the ground will he thawed ready lor tlu* dredge. The

Placer Mining In Yukon-Tan An A Region. 169

dredge is steam driven and the fuel supply, which is wood, has become so depleted that it is now necessary to liaul it several miles, making an excessive cost, which on some ground might so dear that would be conducted at a loss.

Considerable work was in progress on both Davis and Poker crooks and about six or seven men were working on each creek. The gold was recovered by groundsluicing and shovehng into sluice boxes. No winter work has been done on either creek, aside from protecting.

Two men were engaged in prospecting Walker Fork below Cheriy Creek in order to determine the feasibihty of dredging in that vicinity, but the results are not known. Some prospecting was also done on Cherry Creek.

Canyon and Squaw creeks. — On Canyon Creek about 3 miles below Squaw Gulch a steam scraper of one-half yard capacity, drawn by a 45-horsepower boiler connected with a double-drunk hoist, was in operation during the later part of the season. It is claimed that 150 cubic yards could be handled per day of 10 hours. The ground averages about 7 feet in depth and is practically all gravel. The bedrock is slate and mica schist, and about 2 feet is moved in order to recover all the gold. A plowlike arrangement, by the same line of cables that is employed in hoisting the dirt to the sluice, is used to break up the bedrock so that it can be moved by the scraper. The plowing was done in the evening, and two or three men were able in a few hours to loosen all the bedrock that could be handled during the following day. Eight men wtn-e employed in connection with the plant. Dining the early part of the season a scraping plant of smaller capacity was in operation just below the mouth of Squaw Gulch.

On Squaw Gulch three or four outfits of one to three men each were mining by open-cut methods at times during th( summer.

Wade Creek. — The production from Wade Ci'oek in the summer of 1910 was greatly curtailed by a lack of water during most of the season. In the winter 18 claims were worked by 41 men, and during tlie simmier 24 men were employed on 10 claims when the water supplv was adequate. All the summer work was done by open-cut methods and was confined mostly to bench claims.

Chicken Creek and tributains. — Although the lack of wator for sluicing necessitated the suspension of operations on Chicken (/reek during the greater part of the season, two outfits employing 0 men were drifting and 11 men were doing work on four claims for short periods throughout the season. Only one claim was worked during the winter and on this 10 men were employed.

The mining on Stonehouse Creek was about eciually divided between winter and summer work. Ten different claims were worked by three men each. On Myers Fork seven men weiJ:> mming on

170 MINEBAL BBSOUBCES OF ATiASKA, 1010.

claiins Nos. 1,2, and 5 at different times of the year. During the summer open-cut methods were used.

On Lost Chicken Creek five or six men were engaged in mining for most of the vear.

IngU Creek. — Reports from Ingle Creek indicate that considerable work was in prepress, and about five men were engaged in mining during most of the year. Four claims were worked by drifting in winter and open-cut methods in the summer. Some work was done also on Lilliwig Oulch, which is a small tributary of Ingle Creek.

Franklin and Napoleon creeks. — Franklin Creek, the oldest goldproducing tributary of Fortymile River, is still being mined each siunmer by groundsluicing and shoveling into boxes. Very little was accomplished during July and August because of a lack of water, although six men were on the cre in readiness for work when the supply would permit.

Work on Napoleon Creek was also brought to a standstill by a lack of water during the greater part of the season, although two men recovered some gold in the short time that a sluice head was available.

Other streams. — Pay gravel has been found on Fortyfive Pup, a tributary of Buckskin Creek, at claim No. 13, and considerable ground was worked by two men under the prevailing difficulties attending mining operations in a small drainage basin during a dry season.

Hutchinson Ocok and its two tributaries, Confederate and Montana creeks, are known to carry pay gravel, but the extremely dry weather of the season of 1010 practically eliminated all involvinfi: the recovery of jrold, altlioujicli considerable dead work was accompUshed. Two automatic (hims were built. Five men were in the basin durinjij the summer.

bars. — Gravels with a hijrh old content are said to occur on a bench of Fortymile River near the mouth of Twin Creek, which is a tributary from the north about one-half mile below Steele

ft/

Creek. Durin? the summer of 1009 a ditch was built which diverts water from Twin Creek a short distance below the forks. It has a of 0,000 feet, a bottom width of 2 feet, and a p:rade of 6.9 feet per mile. A pressure of 150 feet is obtained, and it is planned to liydraulic the bench travels. No mininti: was accomplished during the season of 1010, owin to a lack of water.

A small dredge designed more especially for ])rospecting was in operation for a portion of the season on a bar of River near the boundary, but the details of the are not known.

On Atwater Bar, at the mouth of Atwater Creek, four men were mining during a considerable portion of the year, and it is reported that satisfactory results were obtained.

Owuig to the low stage of the river during the summer the conditions were extremely favorable for the few men who were wasliing the gravel by the use of rockers.

Placer Mining In Yukon-Tan An A Region. 171

Troublesome Point, opposite the mouth of Franklin Oeek, is still the scene of mining, but very little was accomplished durino; the summer, owing to the fact that the water supply is derived from a small gulch back of the mine which could furnish a sluice head of water only during a period of extended rains.

Seventymile District.

It is estimated that the combined gold output from the Seventymile and Eagle districts for the year 1010 was approximately $10,000. In the Seventymile district about 20 men were engaged in mining, but during the winter little was done aside from prospecting. Early in the spring considerable local excitement was caused by the finding of some coarse gold on Rock Creek near its head. The depth of the ground is about 50 feet, composed almost entirely of muck. As the gold is concentrated on bedrock high values to the pan were obtained, but the aggregate value of the gold content per square foot of bedrock was too small for the ground to be worked at a profit. Several large boilers were shipped to the creek and pros])ecting was continued throughout the summer, but no more encouraging prospects were found.

During the summer of 1909 a ditch which diverts water from Sonickson Creek was constructed, but it was not put into use until bust season, when the water under pressure was used to remove the overburden from the river bar above the falls. The ditch is 6,000 feet long and has a bottom width of 3 feet and a grade of 4.6 feet per mile. A pressure of 150 feet is available. A Kuble elevator was constructed but did not prove adapted to the conditions. The overburden was therefore hydraulicked into the river and the pay gravel shoveled into sluice boxes. On Curtis Bar a small winter dump wius taken out and some work was done during the summer. Two men were also mining on a bar just above the falls, on the north side of the river, for a short time during the later part of the season. On Crooked Creek claims ''Nos. 2 and 3 above'' were worked by 10 men most of the summer. The overburden was removed bv water under a 40-foot pressure. The water was carried in a ditch 2,200 feet long. A small ditch was also constructed for use in working Discovery and adjoining claims.

Mining on Barney Creek was confmed to the operation of the small hydraulic plant which has been in use for several years, and two men were employed in the performance of the work.

During the summer about a mile of ditch was built, which diverts water from Washington Creek near its head and carries it over the divide for use on Pleasant Creek, which is the first tributary of Seventymile River from the north above Barney Creek. It is said

1 Washington Creek heads in the divide north of Seventymile River near Barney Creelc and is tributary to Yukoo River about 15 miles above Charley River.

172 MINEBAL RS801TBCB8 OF AUkSKA, IfflO.

that the benches on the right bank of Pleasant Creek cany gravels ; containing sufficient gold to mine at a profit if an adequate water supply could be obtained, but it is yery doubtful if the quantity available in Wasliington Creeky at the elevation necessary to cany it over the divide by gravity, will be found to be of much assistance.

One man was working on Nugget Creek and one on Broken Neck Creek during the sununer when the water supply would permit.

Values are reported to have been found on Alder Creek. The auriferous gravels so far located lie in or near the creek channel, where the depth of the ground averages about 4 feet. Nuggets valued at $19, $8.60, and $7 and several $1 and $2 specimens were found. Plans were made to do considerable prospecting on Alder Creek during the ¥enter of 1910-11.

Two men were engaged in mining on Flume Creek near the moilth throughout the season. A reservoir and an automatic dam wore buik on the left-limit bench of claim No. 1 . The water was carried to the reservoir in a ditch whidi was constructed several years ago.

EAOIiE DISTRICT.

In the Eagle district mining operations were confine4 to AmLorican Creek and its tributary, Discovery Fork. On American Creek two automatic dams were installed — one on claim ''No. 8 above" and one on claim "No. 2 above." At the upper workings an average of four

or five men were employed the entire season, and after the completion of the dam considerable ground was worked. At claim " No. 2 above" the work was confined almost entirely to the construction of the dam and waste ditch and the opening of ground in preparation for another season. Some mining was also done on two other claims during a part of the season. Two outfits of two men each were working by open-cut metliods on Discovery Fork.

Minor Yukon River Districts.

On Woodchopper Creek during the winter of 1909-10 tliree claims were worked, on which 15 men were employed, and during the summer of 1910 six men were engaged in mining on two claims. The value of the gold output for the year is estimated at $19,000.

Fourth of July Creek gave a production of about $6,000. Four claims were worked in the winter by 11 men and in the summer 12 men were mining on five claims. Both drifting and open-cut methods were used. One automatic dam was in operation.

On Coal Creek an average of about 20 men were engaged in mining during the year. A hydraulic plant was operated under a pressure of 160 feet. The water was diverted from Boulder Creek, which is a small tributary of Coal Creek. It is reported that values have been located on Sams Creek and that about 16 men were either mining or prospecting along the stream.

Two men were mining by open-cut methods on Surprise Creek, which is a tributary of Washington Creek.

Water Supply Of The Yukon-Tamna Region, 1910.

By C. E. Ellsworth and G. L. Parker.

Introduction,

This report has been prepared to furnish for immediate use the essential results of the investigations in the Yukon- Tanana region during the season of 1910.

The work was begun in this region in 1907 and has been continued each*succeeding year. The data collected in 1907 and 1908* and their analyses have been published in detail. Those of 1909' were presented in the progress report for that year in a form similar to the arrangement used in this paper.

The writers arrived at Fairbanks March 31, and until the later part of May the time was devoted to a study of winter run-off and mining conditions and to general preparations for the summer work. In the early part of June, after having commenced the investigations in the Circle district, C. E. Ellsworth proceeded to Eagle and began a study of the water supply in the Fortymile, Eagle, and Seventymile districts, where he continued work until the later part of September. G. L. Parker continued the work in the Fairbanks, Circle, and Salchaket districts during the remainder of the season and was assisted by T J. Shaw during July and August in the Little Chena River drainage basin.

On account of the large area to be covered, the slow means of transportation, and the needs and possibilities of the several districts, it was decided that the data would be of more value if the investigations in the Rampart and Hot Springs districts were discontinued and the remaining time devoted to a more thorough study of the conditions in the Fairbanks and Circle districts.

The writers desire to express their appreciation of the courtesies extended and aid given to the work by many residents of the region. Special acknowledgments for supplying gage readings are due to

I Covert, C. C.,aiid Ellsworth, C. E., WatGr-eupplyinveetlgations In the Yukon-Tanana regioiu Alaska, 1907-: WftteiSupplT Paper U. 8. Geol. Survey No. 228, 1909.

s Ellsworth, C. E., Water supply of the Yukon-Tauana region, 1909: Bull. U S Gool. Survey No. 442, 1910, pp. 251-283.

174 MINERALi SE80UBCE8 OF ATJkaA ifiio.

Messrs. J. P. Carroll, Albert CamitberSi M. Danielson, J. T. Dickinson, August Fritch, Arthur Froelich, Mrs. A. Gustavason, Messrs. R. C. Hall, William Hugel, Alfred Johnson, J. F. Eelley, J. W.

McCluskey, Jack McLin, Dan McPhersoni Charies Martin,

Michaels, Frank Miller, Frank Montgomeiy, Oscar Morrill, W. F.

Munson, James Murphjr, T. E. Phillips, C. A. Pihl, Powers,

John Roberts, E. A. Robertson, Henry Siemer, A. F. Stowe, John B. Tait, Mrs. F. Warren, and Messrs. Robert Warren and John Williams.

Miscellaneous Measurements.

A number of miscellaneous measurements were made during the season of 1910 at points where it was impracticable to attempt to procure daily records.

A comparison of the run-off per square mile at the points where daily records were obtained shows a general trend of similarity, but the daily variations and in some cases the monthly departures from the general average are so great that extreme care should be used in making estimates from these measurements.

The season as a whole was characterized by conaideraUe fluctuation in the stage of the streams, but most of the miscdlaneous measurements were made during July and August, when the run-off was very low and the flow fairly uniform.

Explanation Of Data And Methods.

Tlie methods of carrying on the work and collecting the data were essentially tlie same as those previously used for similar work* but were adapted to the special conditions found in Alaska.

In the consideration of industrial or mining enterprises which use the water of streams, it is necessary to know the total amount of water flowing in tlie stream, the daily distribution of the flow, and facts in regard to the conditions affecting the flow Several terms are — such as miner's inch, and gallons per minute — to describe the (juantity of water flowing in a stream, the one selected depending on the use to be made of the data.

is in most general use for all classes of work, and from it the quantity expressed in otlier terms may be obtained. It is an abbreviation of cubic foot per second, and may be defined as the (jinintity of water flowing second in a stream 1 foot wide and 1 foot deep at tlie rate of 1 foot per second. It should be noted that it is a rate of flow, and to obtain the actual (juantity of water it is necessary to multiply it by the time.

''Second-feet per stpiare mile" is the average number of cubic feet of water flowing per second from each mile of area drained,

iSee Water-supply rajws U. S. GjoI. Survey Nos. 94, 95, and 2()1.

Water Supply Of Yukon-Tanana Region. 175

on the assumption that the run-oflF is distributed uniformly, as regards both time and area.

Run-off, depth in inches on drainage area/' is the depth to which the drainage area would be covered if all the water flowing from it in a given period were conserved and uniformly distributed on the surface. It is used for comparing run-off with rainfall, which is expressed in depth in inches.

The ''miner's mch," the unit used in connection Adth placer mining, also expresses a rate of flow and is applied to water flowing through an orifice of a given size with a given head. The head and size of the orifice used in different localities vary, thus making it a most indefinite and unsatisfactory unit. Owing to the confusion arising from its use it has been defined by law in several States. The California miner's inch is in most conmion use in the United States and was defined by an act approved March 23, 1901, as follows : '' The standard miner's inch of water shall be equivalent or equal to 1 i cubic feet of water per minute, measured through any aperture or orifice." This miner's inch corresponds to the so-called ''6-inch pressure," and is one-fortieth of a second-foot.

The determination of the quantity of water flowing past a certain section of a stream at a given time is termed a "discharge measurement." The quantity is the product of two factors — the mean velocity and the area of the cross section. The mean velocity is a function of surface slope, wetted perimeter, roughness of bed, and the chaimol conditions at, above, and below the gaging station. The area depends on the contour of the bed and the fluctuations of the surface. The two principal ways of measuring the velocity of a stream are by floats and current meters.

All measurements by the engineers of the Survey were made with the current meter, but as float measurements can readily be made by the prospector the method is described below.

The floats in conmaon use are the surface, subsurface, and tube or rod floats. A corked bottle with a flag in the top and weightetl at the makes one of the most satisfactory surface floats, as it is affected but Uttle by mnd. In flood measurements good resuhs can be obtained by observing the velocity of floating cakes of ice or debris. In all surface-float measurements the observed velocity must be niultipUed by 0.85 to 0.90 to reduce it to the mean velocity. Tlie subsuiface and tube or rod floats are intended to give directly the mean velocity in the vertical. Tubes give excellent results when the channel conditions are good, as in canals.

In measuring velocity by a float, observation is made of the time taken by the float to pass over the "run" — a selected stretch of river or creek from 50 to 200 feet long. In each discharge measurement a large number of velocity determinations are made at different points

UINBB&Ii aEBOUBCES OF *T.AaAj WO.

across the stream, and from these observations the mean Telocity for the whole section is determined.

The area used in float measurements ia the mean of the areas at the two ends of the run and at several intermediate aectiona.

Precipitation.

Precipitation records for 1910 show tiiat the runfall at Furbanke was about 15 per cent below the average from 1900 to 1910; at Fort OibboD it was about 6 per cent below the average from 1904 to 1910; and at Fort Egbert it was about 2 per cent above the average from 1903 to 1910. At Rampart a precipitation of only 5.32 inches was recorded, wliich is lower than that of any other year since the beginning of records at that station in 1905 fuid only about one-half the average for tlie last six years.

A comparison of the records of 1910 with those of 1909 shows that at Fairbanks and Fort Gibbon tiiere was a small decrease .in precipitatioiv during the last year, whereas at Fort Egbert tiiere was a considerable increase. At Rampart the decrease was neaify 60 per cent from tlie precipitation of 1909.

Although there is a wide difference from month to month and from year to year in the rainfall at the several staUona in the Yukon- Tanana region, the mean yearly precipitation at each aUtion for the peri<)<l covered by the records is uniformly close to the average of tlie means of nil t!ie stations. In other words, the records show no unifonn diirei-ence in throughout this area.

Tlie foUowuifi tJil.le {jives the monthly at all points in the Yukon-Tan ail a refjion wliere records have been kept subsequent ttt 1903. Sueh scattered records as were kept previous to 1903 have been eoinpiied liy Abbe.'

Monthlij prerijiitnlin, IKalnlul] or m

iirlim. Ill gl/ilioni in Viilon- Tanana region, 19M-I9I0.

!. Sep*. Oa. Nov. Doe. i„

(Tiatlij-. Cleiay

MRia

I 4.ei 4.S2 i.fls I

,JI,ts<

Hi

lAblio, Clevotand.lr., 1

WATEB SUPPLY OF ruKON-TAKANA BBQIOIT. 177

Monthly preeipilation, in input, at tlatiotu in Yukon- TaTuuia rtgitm, 1903-1910 — Con,

.„,

s

Udt

Iki& W07

was

11*06 'Dos

Iso? Iw

iwa

vm

iwe

Mot

:7o

Feb.

:ji

Uor.

aid

Apr.

May.

1.

Aug-

Sept.

Ocl.

boc.

Fairbanks

ft 10

'.as

,S8

1.0fi

3.

i.W

0.2S

10,(8

1,0

I.S1

3.W

Do

.9

1.S7

'.S

:iS

,32

.S

-M

:S

.a

J

4.S .3S

J

'.m

i,io"

J

Do

Las

id

ilo

if

:c8

uio

.Od

Do

1m

Lib

i-

1,98

Lis

10, H

Do

lie

i-fl

1-Oi

L4J

iiT 1 mo*

Do

.W

Z3S

g!i

!S9

'

'-jS"'r::

Do

33 Luo

1%

3.3K

1.7s

i'ai'

if

,1S

Oo

lis

2 3t

Do

I.Ib

.M

I-Is

80

Do

ilf

Do

,og

a

Do

ib:4

f

,410

.3D

if

t3.1fl

Lsa

l.U

3!25

.03 .23

.3e 1 .90

.2g .10

Do

.w

Tr.

Ih'

1,30

i.aft

3

tS

Do

an"

s

1.3B

Ao

io 1 3.'0

1.M

if

'A

if if-f

ir

1.S3

1!

if

U.0

Do

I. Is

".te

.W

3.U

4.S

H'

3,(11

iOl

in

-7>

.3U

in

Is

'if

11,

Do

i.

3. is

3.3S

3.(12

.Os

Do

-ai

1-M

it

Do

i:o

1,04

Do

.W

fk31

Bummlt rokd

tania'cna-

:i4

'in

-w

,ftt

.Do

4"

Oct. 7 toll.

—BuU. 480-11—

r

MINERAL, RESOrKCEB nr ALASKA, IfHO,

Precipitation reconU for June to Spptcmber, iuclusivc, at scverni poiiiU) ill tliP Yukuii-Taiiana region may he summarized as follows:

►

III Futon- Tanana rrgion.

buumi.

Uwn

fhiimlhin

Pmripi-

Ini-hw Y™. 7.54 ijnr

Ifl.in iM

T.8S 1*00 9, S3 1907

llneha).

'"-

Ww

iiwr-idiot iM-iBm

Ibtis-Isiu

-"

'

lU

TLe uniformity of precipitation throughout the Yukon-Tanana region, as already nott'd, for yearly periods Is alao noticeable, though to a leas extent, for the summer moutlis, In the uliove table Fort Egbert has the liighest average precipitation from Juno to September and is 12 per cent alxtve tlie mean for all of tlie stations; Kampart has the lowest average precipitation and is 11 per cent below the mean for all the stations.

The table also shows that a total precipitation as high as indies and as low us 2,74 inclies Uan iH-curred during tlie niiiiiiig sofi-ion and it li'tids lo llii> coiii'lusioii tliiit llie general si'incityof for mining uses during 1910 througliout the Yukon-Tanana reon (with tlie exception of the Rampart district) was not due to an unusually small amount o[ rainfall in the aggregate but rather to ite distribution with respect to time and area. A study of the run-off from adjoinmg drainage basins duruig the last four years indicates tliat a wide difference in stream flow may be expected even tliough geologic and topographic conditions are apparently veiy similar. In order to arrive at any definite conclusions regarding areal distribution of the rainfall by a of simultaneous records, it would be necessary to liave a greater number of rain gages more systematically located. Sucli comparisons as can be made with tlie existing data, however, confirm the general opinion tliat the precipitation is distributed rather unevenly. 'Tliis condition is often noticeable iji the summer, when local showers visit one portion of tlie drainage basin and do not reach another portion.

Water Supply Of Yukon-Tanana Region. 179

Hydraulic Development.

Because of many unfavorable factors, mining by the use of water under pressure has so far played a very small part in the recovery of placer gold in the Yukon-Tanana region. The relatively high elevations at which most of the mines are located and the uniformity in elevation of the sources of the streams make it extremely difficult to obtain a sufficient supply of water at an elevation that will give a working head at the mines. The low stream gradients wliich prevail in the interior make necessary some means of elevating the gravels, wliich in turn involves the use of larger (juantities of water under a higher head than would be necessary if the of the bedrock underlying the gravels was equal to or greater than that recjuired for the sluice boxes.

Notwithstanding the many difficulties which must be oven'ome in order to successfully utilize such means of extracting the gold, several small plants have already been installed and larger ones are under consideration.

The developments in the several districts during the season of 1910 are described in another section of volume. (See pp. 153-172.)

Water Power.

The following tables have been prepared in order to summarize briefly the records of stream flow that have been gathered on streams in the Yukon-Tanana region which ofl'er any possibility for waterpower development.

In comparing the columns showing days of deficient dLs(*harge for several years on any stream, allowance should be made for the difference in the length of periods and also for the part of the setison covered by the records. Ordinarily the longer the period the greater will be the number of days of deficient discharge for any given number of horsepower and the less favorable will be the with some other year in wliich the records extend over a shorter length of time. Also the days of deficient discharge will be a greater percentage of the total lumber of days if the observations include only the low-water months.

The following tables give the horsepower (80 per cent efficiency) per foot of fall that may be developed at different rates of dischartje and show the number of days on which the discharge and the corresponding horsepower were respectively less than the amounts given in the columns for *'dischai*ge' and horsepower.''

Bl80

Mineral Resources Op Alaska, 1810.

Wld-fcBl

ChalontkB River

"Hs"

Wirti-

f;f

im

1'

ino.

July

f

ins.

S"

Ih M

Im

Im

Jo

a

w u w

4a

3 Xt

W

7.

M

J

ol Linin Cblqu Rl

Bacnla Cnek. EDIott Cnet, 8 BkIvi'iiIciI liM.htiryf

nitf (lud .Stirnli/milf rivrrafor 1910.

Dlscharso

Daj-s o( J.-dcii'nt

Horse-

ifiv

"Mir"'

power (8tt

Fori J- Sevr-ntymiU- 1 niii.'

sss

Fortymile River at "kink," July to

Seventybill. Ji!

m

20

2S

,'f

Ib B 3S

s

Winter Rtjn-Off,

Measurements were made during Aprils 1910, to determine the winter flow of several streams in the Yukon-Tanana reon. They were made by chopping liolcs through ice varying in thickness from 2 to 3J feet, sounding, and measuring the velocity at each section by a current meter. The results are given in the foLowing table:

Watbb Supply 09 Yukon-Tanana Beoion.

Winter dMusrge measurements in Yvkon- Tanana region in 1910.

Date.

ABT.e.

Apr. 8. Apr. 17

dream.

Tanana River 3 miles below Chena. . Chatanika River below Poker Crock Salcha River at mouth

Drainaee area.

Sq. miles.

124,000

4o6

2,170

Discharge.

Sfc.'fect. 4,450

Discharge.

mile.

Sec.'feet.

a This area was obtained from the topographic map of Alaska, scale 1:2,500,000, and is therefore only approximate.

It is reasonable to suppose that the discharge of streams in this section during April represents the minimum flow for the year if it is assumed that the supply is furnished by springs in the stream bed and underground drainage, which is no doubt the case.

The results obtained indicate that no general relation between the winter and sunmier flow can be deduced. Sucli a relation could hardly be expected, as the surface drainage is the factor regulating the simimer flow, and tliis element is entirely lacking in the winter season, when all of the surface water is stored in the form of ice and snow.

It is interesting to note that the discharge per square mile of the streams measured is greater for large areas than for small, a relation which is ordinarily reversed during the sununer months. There are not enough data at hand, however, to warrant tlie supposition that this relation exists generally.

Fairbanks District. Description.

The area known as the Fairbanks district extends about 60 miles to the north of Fairbanks and is from 40 to 50 miles wide. The greater part of the region Ues in the lower Tanana basin, but a portion to the northwest drains directly to the Yukon. Generally speaking, the district embraces three divisions — a low, broad alluvial plain, a moderately high dissected plateau, and a mountain mass.

The low, broad plain forms the bottom lands of the lower Tanana Valley, which in this section is divided into several parts by the Tanana and its sloughlike channels. The main slough starts near the moutji of Salcha River, about 30 miles above Fairbanks, and diverts A portion of the Tanana waters. Its course is northward along the foothills of the plateau, and it receives Chena River about 9 miles above Fairbanks. The plain is swampy and is well covered with timber along the banks of the streams. In the vicinity of Fairbanks it has a general elevation of about 500 feet above sea level.

182 MISERAL EESOtJBCES OP ALASKA, 1910.

The pliiU-aii is ilrtiiiifMl streams trilnitftrv to Tanana "Rivet which through ratlxr broad, unsyminetrical valleys, rhieflj dxU'iiiling in a >astsoiithwst (lirectiou. Their bottom range in elevation from 500 to over 2,000 feet above sea level, and the (iiviiling ridges are in general ! ,000 to 3,000 feet above the stream Tliat portion of the plateau discussoil in this report is drained principally by Little Chena ami Chatanika rivers. The upper reon of these drainage basins is crosscut by a zigzag range, which separates the Yukon from the Tanana drainage.

The mountain mass north of this plateau forma what miglit be termed the ape.x of the divide between the Tanana and the Yukon drainage basins; its highest points reach altitudes 4,000 to 5,000 fiiet above sea level and its (rrugated slopes are drained principally by tributaries to Yukon River.

All drainage areas tributary to tJie Tanana are similar in cJiaractep. The streams have little slope except near tlieir source and flow over wide gravelly beds in shifting and tortuous courses, keeping to one side of the valley, Most of iJie channels Iiave rather steep banks that form approach's to , level bottom lands which extend 1,000 to 4,000 feet or more before tJiey meet tJie abrupt slopes of the dividing ridges. The drauioge basins ore 4 to 1 3 miles wide and are cut up by small tributary atreaina that flow ttirough deep and narrow ravines.

A Iary;e portion of the an-ii. Ls covered with a turf, kiiowni as tundra, whii-li is wet. aiul nmssy aiui ranges Iti )hickiicM,s from 6 inches to 2 feet. In some localities this is meadow-like, producing a rank growth of grass and a variety of beautiful wild flowers. Ground ice is found beneatli tiiis tundra in many places, particularly on tJie nortJiern slopes, where the scanty soil supports little timber or otiier vegetation. The .soil of the soutliem slopes is, for the most part, clay, underlain by a mica scliist which affords suitable ground for ditch construction. When stri]>ped of its mossy covering and exposed to the sun it thaws rapidly, so that the plow and scraper can be used to aii vantage.

Above altitudes of 2,000 to 2,200 feet practically the only vetatinn is a scrubby, bushy growth which attains a height of 2 to 4 feet. In general the country below tliis altitude is timbered by spruce and birch, witli scatt-ered patches of tamarack and willow along the banks of the smaller streams. The timber increases in density and size toward the river bottoms, where the prevailing growth is-splice, much of which attains a diameter of 18 to 24 inclies.

Tlie Fairbanks mining district lies between Little Chena and Cliatanika rivers. It embraces an area of about 500 square milee and extends .30 miles north of Fairbanks, which is situated on Chena Slough nearly 12 miles above its confluence witli the Tanana. Most

Water Supply Of Yukon-Tanana Region. 183

of the producing creeks rise in a high rocky ridge, of wliich Pedro Dome, with an elevation of about 2,500 feet, is the center. At least half of the mines are located at an elevation of over 800 feet, and 25 per cent are over 1 ,000 feet above sea level.

QAQING STATIONS AND MEASXJBINa POINTS.

The following list gives the locations at which gaging stations were maintained or discharge measurements made in 1910, in the Fairbanks district:

Gaging stations and measuring points i?i Fairbanks district, 1910.

Tanaiia River drainage basin : Chena River drainage basin :

Chena River above Little Chena River.

Little Chena River above Sorrels Creek.

Little Chena River below FL'h Creek.

Elliott Creek above mouth.

Elliott Creek at mouth.

Sorrels Creek at mouth.

Fish Creek below Solo Creek.

Fish Creek at mouth.

Solo Creek at mouth.

Bear Creek at mouth.

Fairbanks Creek at mouth.

Miller Creek above Ileim Creek.

Miller Creek at mouth.

Heim Oeek at mouth. Chatanika River drainage basin:

Chatanika River below Faith Creek.

Chatanika River below Poker Creek.

McManus Creek at mouth.

Smith Creek above Creek.

Pool Oeek at mouth.

Charity Creek above Homestake Creek.

Homestake Creek at mouth.

Deep Creek at mouth.

Orphan Boy Creek at mouth.

First tributary below Sourdough Creek from right side at mouth.

Cripple Creek at mouth.

Cassiar Creek at mouth.

Flat Creek below Third Pup.

Flat Creek below First Pup.

Juniper Creek at mouth.

Kokomo Creek above Rusty Gold Creek.

Poker Creek at mouth.

Poker Creek ditch near outlet. Coldstream Creek drainage basin:

Gilmore Creek near mouth.

Pedro Creek near mouth.

Fox Creek near mouth.

MINERAL HESOUBCES OF ALASKA, 1910. CHENA nlVER CRAINAaE: BASIH.

Clicna River ilminK Ihc iirni iy'uv between Chtitaniku River on north, Birch Creek on the east, ami Salcha River on the snulh. It has II lenglli of iibout 100 miles ami flows slightly south of west to the luwlaiids of the Tanana Valley, where it empties its waters into Chena Slough. The principal tributaries are the West Fork jind Little Chena River from the north and the South Fork from the south.

Uttle Chena River and its tributaries Sorrels and Fish creeks drain the southern slope of the divide between Chatanika and Chens rivers from the headwaters of Smith and Flat tTeeks to Pedro Dtime, a distance of about 25 miles. The drainage basin is irregular in shape and crossed by a network of small, ramifying streams with precipitous slopes in their upper courses. The portion of the main stream is also steep, having a fall of to 150 feet the mile, but this slope decrea-ses rather to about 18 feet to tlie mile in the vicinity of Elliott and Fisli creeks.

Above Fish Creek the Little Chena flows tlirough ft rather broad, unsymmetrical valley, but below that streAm it takes the center of a deep, rather narrow channel for about 10 miles, to Anaconda Cn-ek. an important tributary wliich enters from tlie left. Below this point the valley gradually wiilens again until the stream reaches the low- Innils tributary to Chena River, with which it unites 6 or 8 miles alMive the conHuence of Cliena 81ough.

Monthly dUdtarge of gtreamK in Little Chena River drainage basin/or 1907-1910,

* Clitut' Strai BboTe Sotrali Crk.

I Drainage nren, T-square miles.)

fix"

Month.

Dlwhargp in second-fwi.

Maximum.

K

Mran. m'

So

.3 0.826

80:2 i:9

i!

1S7

a

7H. 4 .993

7B

Z

290 ' 3. 75 41.1 1 .520

Aug. 1-26.

W5

103 1 1.30

mo.

a

74 S I :il*3

3!0

5isj .m

Watbs Supply 07 Yvkon-Tanaka Beoiok.

Monthly discharge of streams in Little Chena River drainage-basin for 1907-1910-- Con.

Llttto Ohtfui Hirer blow Flih Crek. [Drainage area, 228 square miles.]

Month.

May

June

July

Aug. 1-27

Tlie period, 1 19 da3rs

July

August

Tlie p?rIod, days..

Discliarge in seoond-feet.

Minimum. , Mean.

Mean per

square

mile.

(>4

Run-off

(depth in

inches on

drainage

area).

m

Elliott Crek above month.

[Drainage area, 13.8 square miles.]

July 22-31

August

Sept. 1-10

The p?riod, 51 days,

May 20-31

June

July

Aug. 1 26.

The period, 99 days

July

August

The 62 days

Sorreig Creek near mouth.

[Drainage area, 21 square miles.]

(6

July 22-31

ao

August

Sent. 1- 10

The period. 51 days

May 20-31

June

July

Aug. 1-26

The Deriod . W days

July

August

The Dcrlod. 62 days.

186 Mineral Resources Of Alaska, Ibio.

Dttily ihxrJmrfff.. m lemtui-ftet, o/Chetutand LitUt Chena rivtn and EUiott Cmt/or 1910 fi

Dw.

ctteni Rinr Bbon LtttiF chna Rinr

(dndiiae* an. l.MD Mium diIIm).

'St

KJTH-beknr

as

Il*7

luM. I July.

Aug.

atpi.

00.,

July.

Aug, Inly.

Am.

Jnly.

AiH.

iO

3; 600 2,1150

I.Iso

'b

Mm Km 7W

S

nn

Ho!

m

Vim i.oao

i.m i'.sx I'.m va

Mi

M7

Ms

s™

Stu

,.s

4,700

2,190 2.3tO

1,700

i,nJO

liuM 1,M0

2,080

ilrao 2.mi

3. 'Mo

!S

Lwo

1.7J.) I.Imo 1,620

(1*50

1.3Mi

Ctv

mi

(B

71

Ml)

?!

as

i!

7S 71)

es

S8 (0 (0

s

so

M

U ,2

M

Im

%

in2

Is

20

11 u

i:

afl

s.mo

*.i in

a. a 3. a

7:1

a, MO

i.'Hi

.an

loe

'iS

inrMic* OD drainsgr

Lu

M

VAtSft ftCtPLT OF tckon-tanana heqion. 167

DaiJff HaAargt, in o/SoneU, Fak, and ilUler eredctjor 1910.

Dw.

Somdi Cnekst mouth

Fish riwk l*low Bolo milajx

July.

Aug.

June

July.

Sept.

on. jliJy.

July.

Aug.

Al AQ

a

4.T

4.S

t;

,J!

3)

I.g

J.

i.B

!:

Ao

iO

n

B.T A. 3

B.]

fl.1

S.7

S.4

A7 Aj

G.9

1!

2H

ID.H 1ft. i

iris

1B.0

]a.e

1?.S 18,0

idii

1:

jli

M

S,4

J.*

J.' 4

"1

.1 1 13, a

r

a.

Js

"1

[I.S58 |0.i4 O.S72 O.S

Iu.I)

ft..W

(Kb

op.

mi

duchargrs tor Sorrrls Ci

a Thr rhannrl of Ftah 1.< Thf 'll.wliarBra lor ihu IniMval i

t Tli ll or Miliar Orwlt dlvharRF, hut suntcient ni(.iiir

tidn tbe results ehI. a Rii-tr drainage. liasin

I I'ni).

Date.

-

Sfc.-ft.

U.ll .H9

oha'rte

July 10...

w>-

r

-188 MINERAL BESOUBCES OF AUkSEA, IMO.

OHATANTKA BIVBB SRAXHAaE BASIN.

Chatanika River is fnrracd by the junction of Faith and Mcifanua creeks, which drain tUo high ridge constituting the divide between the lower Tanana and Yukon basins. The river flows southwestin a winding course through a long and rather narrow valley and unites with the Tolovana from the east about 30 miles above the confluence nf that sti-eant with the Tanana. Its course lies mostly to the west side of the valley, which is from half a mile to 7 miles wide and about 80 miles long. The drainage area of the river above its mouth is approximately 1,300 square miles.

Below the junction of Faith and McManus creeks the stream has a shifting, gravelly bottom. In low and medium stages it flows in a series of pools and rapids in a channel 75 to 200 feet wide; during the high-water period it may spread through several channels covering a width of 100 to 400 feet. This high-water channel is nsuuUy wefl defined by step, alluvial banks ranging from S to 10 feet in height.

Below Poker Creek, a tributary from the right about 40 miles downstream from the junction of Faith and McManus creeks, the valley widens and the bottom lands become marshy and swampy- From the left the Chatanika receives Cleary, Eldorado, Dome, and Vault (eeks and other less important streams from the mining district proper. Below these tributaries the valley narrows to a gorgelike channel, which it follows for about 10 miles: below this the dividing ridges disappear and the stream meanders through the low swampy grounds to the north of Tanana River. About 10 mites from its mouth Goldstream (Jreek, its largest tributary, joins it the left.

The average elevation of the divides in the upper drainage area of the Chatanika is between 3,000 and 4,000 feet above aea level, and the altitude of the ridges bounding the vaUey on the east and west is about 2,000 feet. Below an altitude of 1,800 to 2,000 feet the slopes ' are heavily timbered.

The tributary streams from the right are short and precipitous, flowing through V-shaped vaUeys; those from the left have less precipitous courses and broader valleys and gradually lose themselves in the rather broad expanse of swampUke bottom lands.

Watbb Supply Of Yxjkon-Tanana Region.

Monthly discharge of Chataniia River for 1907-1910,

Ohataalka RItw below Faith Creek. [Drainage arpa, 132 square mUes.]

Ohat&nlka RlTer below Poker Creek. (Drainage area, 456 square miles.]

Discharge in seitrnd-feet.

Run-off

(depth in

inencs on

drainage

area).

. Month

Maximum.

Minimum.

Mean.

Moan per

square

mile.

July 17-31

a 514

a28

Aumist

The Dcriod, 76 days

1,990

May 12-20

1,340

July 13-31

Aucust

ICay 25-31

2,000

1,010

JVBti -,,--,-

July

Aumst

Sept. 1-25

The period. 124 days

2,000

June 20-30

July

August

September

Oct 1-14

The period, 117 days.

May 16-31

June

July

August

September

Oct. 1-21

The period, 150 da>'8

May 9-31

Juno

July

August

September

Oct. 1-5

The period, 150 days.

May 17-31

June

July

August

September ,

Oct.1-29

The period, 106 days

3,160

1,740

1,730

3.'i2

l.'M

Hfl90 MINERAL RtSOURCE-S OF ALASKA. 1010.

Daily dia-hargf. in ncconil-fid. of Chalaniia liiirrJoT 1910.

W

D.)r.

wlaw

Ciw*

DUas).

May.

ivac.

luty.

Aug.

.

July.

Aug.

Sept.

si?

g

Mb

Ml

3§D

zw

in

Iw

foa

Sm

13S

i.m ua

Im

an

'S

Os

M

u

at w

W

Ih

m

10)

Its

xia

l.tOD 1.(00

lU IW

Mo

lai

Wl

ini

m

m m

Ih

33

1.0U1

Ku

tm

4S0

1 861

1 ea

i!an

4M

t.im

Ml

Jm

Ko

Ij

W

W

w

S

2.m

Su.1

i3:i

1,Tt

9*t

2.m

0.*30

1,0S

o.4fin

Mauiga-amuemllo.. Hun-oB Itlenlh In

orenl

lielow I'okFT Creek org ablulnnl liy adding to Ihe flow ot tbe river haianllta dilob. It tb not lu detrnnlne the dlwharef of in crhannrl condiljons, hul as Ihc How was uniform aod Dot a Ufg* I ihi> vBiims given uf eivirect vrlihlti S to 10 per cent. A Osh dam . oQ the gage from July 3 Aug. 13. when the dam was

Wateb Supply Of Yukon-Tanana Region.

DaaydMu,in

ttcondr/at, of McManiu, Che

"itf,

and llomttUxtt crtektfor 1910.

tlrUBom at moul b i (dnlimge icn. M iHiiinre mLlwI.

''.wTBOMk.i

almimlhl.

lOnilniluB HTnt, R.ft

aqiiaiB milr-).

tair.

j™.

July,

M.J-.

Ji.na,

July.

Msy.

Junf. July.

art as ISO

2a

an

K

Ib.D

g

]§3 Im

Hs Ib

M IfJl

32

Is3

a

3, J S.2

Is

S.S

?1

M 2.B

s

t '

J

1.6'

10 1

M

a

3U

236 1S6

I. S3

Mcu per Bqiun

"ssisas

a Thr dlechsTKH! ol HvMaaus ami SO and seconil-rwt.

fc The rtischarpsgf rhariiji II ooniJLtkins unci nuiirBcipnl measurei

Mtscellanfou* mraaiirei

II' creduBTBODl]' spproilmuteun acivunt n Ihe ('hataitikn IHifr drninnge basin ii

. l-ool fre*li ot month

da

. Hope Creek at mouth

. bnp Creek Bl mouth

'Tpnan Hoy Creek at mouth , ,..

Inl [ribulary behiw Sourdough Creek [ram right aide ui

. ripple Ciwfc St mouth

. Casstar Creek at nioulh

Flat Cnekbelair Third Pup

192 MINERAI. BESOt'Bl.'Ee OF A1.ASKA, 1910.

Ooldstbeau Cbeek Dbainaqe Basin.

Gotdstream flows southwest ward, a narrow, winding ooursc, betwpfu tlie drainngo basin of Cliatanika River on the right and the Little Chena and Tanaiia basins on the left, paralleling Cbatanika River, which it enters from the east, and drtuning the central portion of the Fairbanks mining district. It is about 70 nules long and it drains an area of about 500 square miles. About 40 miles below its source it leaves the dividing ridges and for the remainder of its course to the Chatanika flows in a zigzag channel across tlie soft, murky flats northwest of Tanuna River. The stream bed is sandy and slufting, and tlie channel is deeply cut in the alluvial soil that firms the bottom lands.

The u])per portion of the valley is drained by Pedro and Gilmore creeks, which join to form Goldstream Crek near Gilmore, about 12 miles north of Fairbanks. Fox Creek enters the main stream; from the right about 2 miles below this junction.

Miicellaneout nuaxurcmenli in Goldalream Crret drainage batin in 1910.

Data.

onrt lomUtr.

Dp

per

mile.

Gilmore CrreV immt niuulh

af..

atc-Tf.

Aug. 10..

Salchaket District. Debobxftion.

The Tanuna prciinct, wliich includes the Salchaket district, embraces the area drained by the Tanana and its tributaries from and including Sakha River to a point on Tanana River sotfth of Lake Mansfield. The larger streams included in this area are Salcha, Goodpustor, Volkinar, antl Hoaly rivers from the north and Delta River from the south,

Tanana Biteb Dbainage Basin.

Tanana River rises near the international boundary line and flows in a general northwesterly direction for about 440 miles to its junction with Yukon River at Fort Gibbon.

The river in general follows the north side of the valley and is one maze of channels and islands. At McCartys, just above the mouUi of Delta River, which is 95 miles from Fairbanks by the Government road, it flows in three cliannols except at extreme tow water, whoi the jniddlo one is dry. During the summer of 1909 the Alaska Road Commission installed ferries on the right and left cbiaiULeb wd bridged the center one.

Water Supply Of Yukon-Tanana Region.

Tenderfoot and Banner creeks, which have been the largest gold producers in the district, are tributary to the Tanana about 75 miles northeast of Fairbanks, at a point about halfway between <}oodpaster and Salcha rivers and from the same side.

Canyon Creek is a small stream which flows into the main stream from the north about 5 miles below Richardson.

Salcha River rises opposite the head of the South Fork of Birch Creek, about 25 miles from the Yukon. The average fall of the river from the Splits to the mouth, is 10 feet to the mile, and from a point about 2 miles from the summit of the divide at the headwaters it averages 19 feet to the mile. At the mouth, wliich is 40 miles from Fairbanks, a ferry, post office, store, and roadhouse are located and good accommodations are at hand for the traveler. Redmond Creek enters the Salcha from the south about 15 miles above the mouth. Junction and Mosquito creeks, which join to form Redmond Creek, drain an area 6 to 8 miles north of the Tanana and parallel to it.

Little Salcha River, which is tributary to the Tanana from the east, enters the river at a point midway between the town of Salchaket and the Salcha telegraph station.

aAoma stations and MEAsiTBiNa points.

The following list gives the locations at which gaging stations were maintained or discharge measurements made in 1910 in the Salchaket district:

Gaging sttUions and jn4!asuring points in Salchaket district 1910.

Tanana River drainage basin: Banner Creek at mouth. Canyon Creek near mouth. Salcha River at mouth.

Junction Creek above Moose Lake outlet. Little Salcha River at road crossing.

Monthly discharge of Salcha River at mouth for 1909-10. [Draiiiiige area, 2,170 square miles.]

Discharge in

Mean.

Kun-()1I

(:lenin in

inches on

drainage

area).

Month.

Maximum.

Minimum.

Mean pT .stjuaremile.

July 41

September

1,750

3.k:w

3.ti90

1.K3

1.%

The Deriod. 89 days

.

4. .')4

May 12-31

f..(40 K.220 (i.l20

2,180

1,120

3,040

1,880

June

1.H3

July

l.(Ni

Atw. 1-19

The Dcriod. 100 days

9:k)

2,990

98319**— Bull. 480—11 13

194 MlNEBAl- BESOUllCBS DF AL.\SKA, 1010.

Diiilij iliiehare, in tevtind-feel, Crcei, Saleha Him. and Junrtioti Crert/ar 1910.

D.y.

nuuier nonr n mil till, (ilralnn am

imt-

IiU)-.

Aug.

9epl.

IJny.

Jium.

Inly.

Ant.

i™

Jirty.

n.

f.

is

S.l

a. I

I!

lJl!7

Ii.' I

lot

K

lf,,u

ta

5;™

ta

i.nu

Is

!i.mt a, mi

til

a.wii

i.aio

ils

1,190

iin

Si

sis

Vo

1;

4>.

*.o

S.1

sis 3. a

S.3

fi.7

n.3 11. a

'ft

issil;

(1.30

0,11

n.iB

Lm

"."

B.U O.Iw

0.U

n.sw

n Tlie dbcharRta st Banner iind

I' Tlie iliscliitrKea of Saleha Kit-er

Jfimrllaiirinii

HI creeks are pnly approximate on account at ahiltlng chanuitl [h nrelHuwcl on a ratlngcurvo (hat 19 well defined throughout. In ill Satrhalrt dUtrict in 1910.

Chicle District.

Debcbxftion.

The area north of tho Yukon-Tiuiiinn diviiie between longitude 143° 40' and 146° 50' is known as tlie Birch Creek region of the Circle district. Generally speaking, It consists of two geographic divisions— a low, broad alluvial jilain and n dissected plateau.

The northwestern portion of the low, broad plain forms the bottom lands of the Yukon Flats north of Crazy Mountains; the southeastern portion is an irregular orea by a low ridge along the

Wateb Supply Of Yukon-Tanana Region. 195

Yukon, the Crazy Mountains, and the range of hills 20 to 40 miles farther south. This portion is cut by Birch and Crooked creeks; it is well timbered along these streams and contains large areas of meadow-like swamp land that furnish forage for both summer and winter use.

The plateau division, whose longer diameter trends east and west, lies between two distinct ridges — the eastern extensions of the White Mountains. The ridge to the south is high and barren and forms the main Yukon-Tanana divide; that to the north is lower, irregular, and barren, separates the upper tributaries of the Birch Creek basin from the lower, and is itself divided by the deep canyon-like gorge through which Birch Creek flows on its way to the Yukon.

At elevations of 2,000 feet or more above sea level the country is as a rule barren and rocky; below this altitude, especially in the flats where Birch and CYooked creeks join, considerable timber is foimd.

aAoma stations and measttbing points.

The following list gives the locations at which gaging stations were maintained or discharge measurements made in 1910 in the Ciicle district:

Gaging stations and measuring points in Circle district 1910.

Birch Creek drainage basin:

Birch Creek below Clums Fork.

Birch Creek at Fourteenmilo House.

Fryingpan Creek below forks.

Great Unknown Creek near mouth.

Clums Fork at mouth.

Mcl.<ean Creek at mouth.

North Fork of Birch Creek drainage basin :

North Fork of Birch Creek above Twclvomile Creek.

Ptarmigan Creek at mouth.

Golddust Creek 4i miles above mouth.

Butte Creek at mouth.

Bear Creek at mouth.

Twelvemile Creek at mouth.

East Fork of Twelvemile Creek at mouth. Crooked Creek drainage basin:

Crooked Creek at Central House

Porcupine Creek above ditch.

Porcupine Creek below Bonanza Creek.

Bonanza Creek above ditch intake.

Mammoth Creek at Miller House.

Mammoth Creek ditch at intake.

Independence Creek at mouth.

Miller Creek at claim "No. G above."

Miller Creek at mouth.

Boulder Creek at trail crossing.

Deadwood Creek above Switch Creek. Preacher Creek drainage basin:

Preacher Creek above Bachelor Creek.

Bachelor Creek below Costa Fork.

Bachelor Creek at mouth.

Co0ta Fork at mouth.

196 MISEUAl. IIKSOL'KCES u¥ AlasKA. IHIO.

Birch Obeek Dka.Ihage Basin.

Birch Creek (lows iiilo Viikoii ll'iyor ni n |iinl, lUmost oxnctly on the Artaii: Ciivlo ajul abuut 25 milo diitTtly wi-st of Fort Yukon. Its mouth is about 5 miles west or tlie coiifliicnco of Chuidalar Kiver with the Yukon.

The lirninage conies almost entirely from tJiD south and west through a roniplox system of water nurses, and in outline tlio basin is oxtromeiy unymnietrical. The hi'adwatt're iiilt-rock with those of little Cht'ua and Chatanika rivers and flow cant for almut fit) miles to tlio juncIJon of the Soutli Fork, when' the stream niakt-s lui abrupt turn iiorthwanl. About 12 iiiilps beyond this point it leaves the mountainous country and tho lowlands of thu Yukon, through which it sluglily flows ui a mcaiideriiiH chaiuu'l for over 100 niilM. muglily paralleling the Yukon at a distance varj-ing from 10 to 20 miles.

The principal tributaries from the south and east are Clums Fork and the South Fork. the and Iho North Fork nml -Harrison, Crooked, luid Preaclicr creeks arc the chief branches, llie headwatets of llie South Fork rise opiiosite tliose of Salina and 0barley rivers.

Montlily ditiMarijr TSirrh t?rect at FmaUenmiU Ilotarfor 1909 (o I9tO.

Dtsihoni- In

secotid-leet

Ruitoir

Uauper

!:3

'm7

i.iio

.see

,L

Thrporlod.Oediiys

i.

S.36

1am

Uj4

W2

1.W

:s72

'I

2,510

i.Nin i.m

i;

T!

6,020

2,010

.m

Wateb Supply Of Yukon-Tanana Beoion. 197

Daily ditAarge, in teeond-feel, o/ Birch Creek and Fryingpan Creek/or 1910.

Birch Creek helow

503.Jiu

FrrinEmn l-low Aelortsi lilrjlluuse Bwo 15.B squBiB miteaj.

July.

Aog.

uoy.

June.

July.

Au,.

Sept.

.

June.

J*.

Aug.

l.olo

s

m

lot

fl

2H

£60

(T

TJn

5fa

Sj4

ana

it

OfU

in

l.SlO

l-SCO ,330 MS

7Ss W9

So]

Ml

i:24o

(i!u70

4, aw

4:730 a, 140

a;4W

Lmo

a, 040

3.BS0 (i.oon

1,280

i'i

l.iOJ

!S

1,010

i.nsn ito

i,aoo

flso SO8

Mtl

lioao

'1

73S (Ms

1,3(]0

'mo 1,000

1,410

ilao

ilaw i.sno

l!4.'U

.Omo

1,080 l.OSO

(1,S 6,4

-i.S 4-S

S.7

.a

A3 A 4

f! t:

a.fi

s

'S

mi

3ffi

I'.ese

17; 0

£.1

a.B

A7

&8 Ao

tl

£.3 A3

K

??

is 1:5

altfio

s.wa

i.iia

4U

i.

0.fil

i,rau i.osa

B.Ob 6.M

Ifam p=r square

HurwffCddpihln Indmim dnilaeeweo)

l.SS

..„

Tba dlschaiifes ot Birch below Chims Fork oi

knoM mine curve baton' 700

uri'until vnloctlycurvKs, ami - " LX'onii-fcM.

'ThediactaaijusolFrTingpaDCrsek Br Uitcellanfous n:

n/a III liirch f'refk drainage basin in 1910.

n'\ iwilily.

sn-.-yv.

MINERAL DESOURCES OF AUiSKA, 1910.

North Fork Of Birch Creek Drainaqe Basin'.

Eagle anil Ptarnufiiin civeks, wlmse lieftiin'uU'.i's are opposite thoao of Crooked Ciiek, Join to form the Norlli Fork of Birch Crei-k. Below the j'uuctiou the North Fork takes a soutUwestwanl coiirec for about 7 niiles, to the mouth of Twelvemilo Creek, whore it turns abruptly to the south and follows that direction for about 8 miles. Here its waters unite with those of Harrington Fork to form Birch Creek which flows east to its coiifluene* with the South Fork, a distance of approximately 45 miles.

Begitming at tlie head, the main tributaries from the north are Fisli, Bmir, and Twelveinile creeks. From the isouth, in the same order, Golddust and Butte creeks are the only impurtajit strains.

UiicfUaiuouM nuatvrementt in North Fort of Bireh Creek draitiofft batin in 1910. fl

Dot*.

einim und loHiltly.

Iw

Dteh...

Diwhum

NofUi Fork ol Itlwh Creek al™ Tw-

Ooldduit Creek 4) mil nbove moulli

is

it

Ho.U

Juli-as

Crooked Creek Drainaoe Basin.

Crooked Creek, which is formed by the junction of Mammoth and Porcupine creeks, meanders through a rather broad valley for about 30 miles and discharges its waters into Birch Creek about 10 miles above the Fourteenmile House. Not far below the Central House the valley loses its identity in the flat.s of Birch Creek.

Mastotlon and Independence creeks unite to form Mammoth Creek, which receives Miller Creek about 2 miles below this junction from the west. The total length of tliat portion of the stream called Mammotli Creek i-s less than 4 niiles.

Deadwood and Boulder creeks are tributaries from the south, below and above the Central House, respectively. They follow parallel courses about 3 miles apart, with a length of about 18 miles.

Albert Creek, the principal tributary fi-om the north, drains the southern slope of the Crazy Mountains.

WATER SUPPLY OF YDKON Daily dMwrge, in second-Jcel, of t'rooted, Pore

-Tanana Region. 199

ipine, and Bojiaiaa creeta/or It/IO.

Day.

Craokifd CTMlt Bt am, 101 square 1

Cta-

imniiiliwtr(,lnilna 39.9 aquuv nillps).

Do-

>bav?illU:b

Ifa)-,

Ju

July.

'

Aug.

July.

A.U.

ft-pt

Jiuir. July.

2M

m

m

K

am as

44S

if

iia

JiA

so

Bo W

H

.0 8,7 S.0

,0

S.D

ra'

f;

did

S.t

S.7 3.T

a.T

S.7

2S

fl.3 .3

!i

la,*

to

Si

f..

3b' a

Id

iia

si

4fl

,

3S

f

in 1.1ft

n.o

1.M

RutHSTTIleplh Id

'a

ai

I.B7

a Illsrhucr ol rnnkeil Creek al <'f viral tluiise : XI cond-iret. ThecliliafTOaot Pafcuplw nnil I!onaniam*l

c The dlwhsigpa o( Pgrpiiplne Creek below Bouu

re baited oej a nilii curve fairly WHli'delliuKl

r

SOO MINERAL nESOl'RCKhi OF AlJiSKA, IfllO.

Iiaihj rfiirAciryf, in of Mammoth and Dtiahenod rretti/or 1910.

X.U'i'iunttnlla).

Uoidwiwl rrk Shore

liny.

„„

Aug.

S.pt.

u.a

B.n

M

to

m

w

W

u.

m

4S

?i

Si

Is, I

It

"A '

ru

is

Is

Ht

4.G

Hh

G.4

m

Ij*

fiis

.3

l.:.i: n.inlmgfum)

" "

o Tho ilischocsrs of Miinimuth (.Twk CTPBk Dip lunounl of water <iivpr1l bj for certain pp-riods UiirinK low water on

b The discharges of Deadwood Creek

HillKC Uowe are obtaJDCil by adding to tbe dischug of the

n BtTouat of Innutni'ient data retnrdlnK (he flow of the ditch.

: ahove Switch Creek are based on a well-defined cune throngtuut.

id-/eel, of Bonanza Creel dUch at intake Jot 1910.

Day.

May.

July.-

Day,

May.

Junt.o July.s

Ang.

2l'

ao

IK 0 1 17 f

I8.B

U.9

S.0

9,0

10:2

,,

WATEB SUPPLY OF YtTKON-TANANA BEQION.

Miscellaneous measurements in Crooked Creek drainage basin in 1910.

Date.

Mny 29. June 5. . July 14.. July 23. May 29. June 5. . July 14. Do. July 23. July 21.

Stream and locality.

Mammoth Creek ditch at intake

do

Independence Creek at mouth

Mllier Creek at claim*" No. above".

do

do

Miller Creek at mouth

do ,.

Boulder Creek at trail crossing

Drainage area.

Sq. miles.

Discharge.

Sec.-fl.

3,3

G

Discharge per square mile.

Sec.-ft.

.G4

Pkeacheb Ckeek Drainage Basin.

Preacher Creek rises near the headwaters of Chatanika River and Beaver Creek and flows generally northeastward for about 65 miles, entering Birch Creek about 50 miles from the Yukon. It drauis an area of 1 ,090 square miles, ranging in elevation from over 5,000 feet at the he,ad to about 700 feet at the Birch Creek flats.

The main tributaries are the North Fork from the north and and Rock creeks from the south. Bachelor Creek is a small but economically important branch from the south near the head.

Daily discharge in second-feet of Bachelor Creek below Costa Fork for 1910.

[Drainage area, 11.4 square miles.]

July 11 6.6

July 12 6.4

July 13 5.9

July 14 5.3

July 15 5.2

July 16 5.0

July 17 5.6

July 18 8.5

July 19 8.2

July20 7.8

July 21 7.6

July 25 8. 1

July 26 7.6

July 27 7.4

July 28 7.1

July 29 7.0

Jqly 30 8.5

Mean 6.93

Miscellaneous measurements in Preacher ('reek drainage basin in 1910.

Pate.

July 21

Do

July 11

Stream and locality.

Preacher Cyeek above Bachelor Creek

Hachelor (!reek at mouth

Costa Fork at mouth

Dminage area.

Sq. miUs.

Discharge.

Discharge

per scniare

mile.

1 The discharges are only approximate on account of shifting channel conditions.

Sfc.-ft.

202 Misekal Jiesouhces Uf Ai.Aska. 1910.

FORTYMll.K niSTRICT.

IiOCATION OF ABEA.

It seema desirable in a wnter-siippiy discussion to make the boundarii'8 iif tlio districtH descnbed coincide with those of corlain drftinage areas ratiier tlian to make theiii conform witli those of precincts or recordmg distncts, whicJi may include partial drainage areas, as in the Fortyniile aiu! Eagle precincts. Therefore! the Fortymile district will be considered to be the area drained by Fortymile Itiver and its tributurit- Tliis area haa beeu topographically surveyed and is covereil by three maps ' separately publislied or in process of publication, The topoirniphy, Reolugy, and jild placers of this area have been described by Prindlc-

QAOINa STATIONS ANS IfEASUBINO POINTS.

The following list gives the locations at which ging stations were maintained or discharge measoremenls made in 1010 in the Forty- J mile districl.:

(Inging slnlinii ami innii'iirinif ifiiiiti in FiiTlymUt iliurrirt,

Fortymile River drsinagi.- baBiii: Fortymilti Kiver at Sleelo Vreek. King Rolomcn l.'refk al mouth. Liberty Creek at mouth. Dome Creek at trail croasing. Steele Creek at mouth. Canyon Creek below Squaw Gulch. Squaw Gulch at claim "No. 1 above." South Fork of Forlymile River drainage ba-iiD:

South Fork o[ Fortymile Rivir below Franklin Creek.

Mwqiiito Fork below KechumCuk i'reek.

Kc<'humtuk Creek at mouth.

Gold Creek above Willow i'reek.

Gold Creek 1 mile above mouth.

Walker Fork above Poker <'reek.

Walker Fork above Twelvemile Creek.

Poker Creek one-half mile above mouth.

Davis Creek I mile above mouth.

Wade Creek at claim " No. 10 above."

Napoleon Creek at mouth.

Bu<;k!<kin Creek above Forlyfive Pup.

Fortylive Pup at i-laim No. i:j.

1 FortymilB quadransle' Maps tan be obtained from the Dirwlur, 1". S. (leul, Purvey, V D.CutSCBntspercopy.

Ctrcle quadrangle; Cuntaineil In BuJtelln 2e5,whlchran bKolilgtiniMl rmiii llif I'irprtor, V,.S vey; ulso In print (ks a aeparuie piibltcatlon, price 10 cents.

1 Prlndle, I.. U., The gold placers at the Fartymlle, Birch Creek, uod Kairbuuk: regina. A U. S. Geol. Survey No. 2U,

Wateb Supply Of Yukon- Ax Ana Region. 203

Fartymile River drainage basin — Continued.

North Fork of Fortymile River drainage basin:

North Fork of Fortymile River above Slate Creek.

North Fork of Fortymile River above Middle Fork.

North Fork of Fortymile River at the *'kink.**

Slate Creek at mouth.

Champion Creek below Arkansas Creek.

Champion Creek above Bear Creek.

Champion Creek at mouth.

Bear Creek at mouth.

Middle Fork of Fortymile River at mouth.

Bullion Creek at mouth.

Hutchinson Creek below Confederate Creek.

Hutchinson Creek below Montana Creek.

Montana Creek at claim No. 7.

Fortymils River Drainage Basin.

Fortymile River* is tributary to Yukon River at longitude 140° 30' west and latitude 64® 30' north, about 50 miles below Dawson, Yukon Territory, and approximately the same distance above the town of Eagle, Alaska. It has a drainage area of 6,350 square miles, about 4 per cent of which lies in Canadian territory. The basin is roughly symmetrical and the extreme north-south and east-west dimensions are each about 100 miles. The stream flow is predominantly from west to east. The main Fortymile River is formed by the North and South forks, which unite about 40 miles in an air line from the Yukon. On the north the tributaries interlock with those of Mission Creek and Seventy mile and Charley rivers in high, rocky ridges of which Glacier Mountain is the most prominent feature. From the west Gpodpaster, Volkmar, and Ilealy rivers take the adjoining drainage from mountains equally rugged. In tlie soutlieast portion the streams liead in a country of relatively low relief and at a distance of only a few miles from Tanana River. Ladue Creek and Sixtymile River form the opposuig drainage on the east and southeast, the moderately low dividing range being accentuated by several large dome-shaped mountains.

Near the international boundary the river flows througli a narrow rock canyon from wliich it emerges into an open valley and takes a more moderate grade to its union with tlie Yukon. A promment feature of the lower Fortymile is the well-defined bench which marks the elevation of an earlier valley floor. At Steele Creek the bench is about 500 feet above the water level. Tlie of the present valley floor and that of the older one become coincident near the mouth of Kechumstuk Creek at an elevation of about 2,000 feet above sea level.

The principal tributaries below the forks are Steele, Canyon, Smith, and Moose creeks from the south and O'Brien Creek from the north.

Bo Gilted iMCMise itsoonfluence with Yukon River is 40 miles below the old trading post of Fort Reliance.

MINEBAI, HESOUBCEe OF ALASKA, lUW.

rond-, tif FTtymiU flitwr at SiteU Crtti/oT l$tO. IDmnnec nmt, S, UK advan inlln.]

DBy.

lam.

A Uk.

.

Dur-

Jan..

July.

Ang.

T.Md 6,0M

4, an 3. em

is

Is

i.njti i,nflo

1.5U0

8U

1:1

I.Iw

a

l.MO

no

Tm

Job

on

Hod

tso

i.iso

l.UO I.OZD

g

13, Mo

„

1.B7D

n.as

o.xa

In inch

in

i>(n2 (SteAnrge. in teeoiid-ftu, of Stede

Carin.

and Sqwiw crerbifor 1910.

StwIeCneknimoinho (dminwe Brto. IS-B square mlloi).

Canyon Oreak licJuT Eqiuw Qulth aMnlnaiW ortB, ,4 square

Squaw Grilob at

Ang.

Bopt

Jnly.

Auk. SPPL

My.

n

&9

'il

Sept

a!i nil

3,0

a.i

Sifl

las

2, a

a.0 a. 8

S.4

4!o

ia-0

s

iK.n

S.6

an isol

(Ik , 18.0

S.9

3.S

Is

1,8

B.7

)4S

no

'Is

ia,o ao

S)

S7 Ti

Ig

3B

i.se

o.eM

"'"

.S

9.2t

— —

Kxin-ofl (depth Id inches on' "drainage

aw

Wateb Supply Of Yukon-Tanana Begioit.

MiKelUmeous measurements in Fortymile River drainage basin in 1910,

Date.

June 27. July 30. Juno 27. July 30. June 28.

Stream and locality.

Kine Solomon Creek at mouth.

Liberty Creek at mouth

do

Dome Creek at trail crossing.

Drainage area.

Sq. miles.

Discharge.

See.

-ft.

Discharge

per square

mile.,

See.-fl.

SOUTH FOBE: of FOBTYMHiE BIVEB DBAINAGE BASIN.

The South Fork is formed by the junction of Dennison and Mosquito forks, wliich unite about 25 miles above its mouth. Below the forks the river flows due east for about 4 miles to a point just below the mouth of Atwater Creek, where it makes a right-angle turn and flows northward to its confluence with the North Fork.

The principal tributaries from the west in sequence upstream are Butte, Buckskin, and Franklin creeks, and from the east Uhler and Napoleon creeks. Walker Fork, and Atwater Creek are the main drainage channels.

Walker Fork, which is the largest tributary of the South Fork, joins the main stream about 16 miles from its mouth, a short distance above Napoleon Creek. It rises in Canadian territory about 2 miles beyond the boundary, flows westward for about 35 miles, and drains a total area of 414 square miles. Its principal tributaries from the north are Wade, Twelvemile, Davis, and Poker creeks. From the south, Liberty Fork and Cherry Creek are the most important affluents.

Mosquito Fork, the left branch of the South Fork,, heads at an elevation of 3,000 to 4,000 feet in a ridge paralleling Tanana River and about 20 miles from that stream. The general direction of flow is northeast for about 75 miles, and the drainage area comprises 1,120 square miles. Chicken Creek is the first tributary from the north, and although of small drainage area it is economically important as a gold producer. Gold Creek joins from the north about 12 miles above Dennison Fork, and Kechumstuk Creek enters from the same side about 8 miles farther upstream. Near the mouth of Kechumstuk Creek, at an elevation of about 2,000 feet, an abrupt decrease in stream gradient is noticeable, and the valley above this place widens and becomes swampy. The valley floor narrows again about 8 miles above, at a point where a spur from the south approaches the stream. This spur marks the lower end of the flat swampy area known as Mosquito Flats, which constitutes a large portion of the upper drainage area of Mosquito Fork. These flats extend along the stream for about 20 miles and at some places are 12 to 14

|yj06 MINKRAL ItESOUBCES OF AIASKA, 1010.

miles wutc. They are a tangle nf lakes and sloughs, and it is said tliat during a wet season tlipy arc practically covered with water.

Dennison Fork has its source in a country similar to that of Mosquitn Fork, ami the ridgo separating its drainage from that of Tanana River parallels the Taiiana at a distance varying from 4 to HI miles. The fiat basin at the liead is not so pronounced as timt of - quito Fork, but the valleys are broad and swampy, with very gentle slopes. The lUainage area is 1,5-K) square miles, about equally divided between two forks which uuito to form the main stream about 12 miles above its mouth.

Vail!/ diirhargc, in -frel, of Soutli Fort. Mosquito Fork, and Ktdmouhit Craft f.ir ism."

'Aiuiklln c™k

hm square miles).

Hoaquito Fork brow

Jaly.

Aog.

July.

Aug.

.

on.

Aug.

.

J

Is

isa

1,13) Ww

Tdb

Too Ib S)

Mw

m

w

ao

4ag

S18

ass am

17S S7

S2

a

m

Km Iso

8S

lUB

Sb

Zi

Ij!

is

3S

Ui.7 U.8

U.4

4Z

%

laia

Wo Mo

M7

Sk

So

J?

0.1S8

o.is

B-Im

Ih

Q.iii

0.O7D

1.0.S1

o.abi

3D, 4

0.D7D

o.

se sUtloDs uc billy well defliwd 10

Water Supply Of Yukon-Tan An A Eegion.

Daily duduarge, in second-feet, of Walker Fork, Wade Creek, and Forty-five Pup for 1910.

Day.

Walker Fork above Twelvemile Creek a (drainage area, 70.2 square miles).

Wade Creek at claim "No. 10 above" ft (drainage area, 23.1 square miles).

Forty-five Pup at claim No. 13 e (drainage area, 9.1 square miles).

July.

Aug.

July.

a8

Aug.

Sept.

July.

Aug. Sept.

a7

'26

ll.O

3 :

9 :

ao

24

Mean

Mean per square mile

Run-off (depth in inches on drainage area)

o The rating curve for this station is fairly well defined below 50 second-feet dftcharge; above that point it is only approximate.

6 Diacharf at this station from July 7 to 13 and 14 to 26 and July 28 to Aug. 1 were determined from comparative hydrograplis and are only approximate. The rating curve is fairly well defined below 25 seoond-feet discharge.

c The discliarges given for this station below 20 second-feet are probably correct within 10 per cent.

Daily discharge, in second-feel, of Buckskin Creek above Forty-five Pup for 1910.

[Drainage area, 33 square miles.]

July 11 4.3

July 13 4.8

July 14 4.3

Aug. 4 3.3

Aug.5 2.9

Aug. 11 12.4

Aug. 21 4.3

Sept. 1 5.3

Sept. 4 4.3

Sept. 5 3.9

Sept. 13 3.9

Mean 4.88

1208 MINERAL BESOUKfES OF AIiSKA, IDUI.

ifurellaneoli* metuuremeHU in SouOi Furk of Forlymik Hirer drainage hajiin in liljo.

Btnoi an I] )olilr.

Dischonn.

1.S

Poker mill- ikboremouUi

Nobth Fobe Of Portymilb Riveb Drainaoe Basin.

Tlie North Fink drains a large area nortli ami west of the iuhid stream, rising in inegular ridges to heights of 3,000 to 6,000 feet. Near the liciidwuters th valleys are broati with gentle slopes, but nearer tlie mouth they become canyon-like, with prominent benches, which are merely continuations of those already mentioned in connection with Fortyiniie River. The drainage area ts 2,120 square

The principal tributaries from head to mouth are Comet and Champion creeks fr()m the east, and Slate Creek, Middle Fork, Bullion and Hutchinson creeks from the west. The drainage area of the Middle Fork is 1,110 square miles, which is 52 per cent of the total driihiiige of the North Fork. Its beadwatcrs drain a flat basin-Uke country smaller than but similar to that of Mosquito and Dennison forks.

About 3 miles below the mouth of Hutchinson Creek the river originally followed a large meander locally known as the " kink." Although the distance around was 2i miles, the two channeb at the neck of the meander were separated by a sharp rock ridge only about 100 feet high and about the same distance in width at the water level. Several years ago a channel was blasted through the rock ridge to divert the water and thus drain the meander for mining purposes. A fall of about 17 feet is now concentrated in a horizontal distance of only a little over 100 feet, which gives possibilities for development of considerable water power. (See table, p. 180.)

Watee Svfpl.Y Of Yukon-Tanana Region. 209

DaUy JUxAarge, in iwond-fett, of North Fork and Hulrhintonaiid Montana cTeek/or 1910.

North Fork of Forty- UtddleFofk.fdfBlnmiles). ' '

North Fork of FortyiulLo River

miles).

below IduDlann

(dralmise

Montana Creek

July.

Aug. [Sept.

IX't.

July.

Aug.

Sept.

July.

Aug.

July.

Aur,

lU

Iw Db

eio

2M

Is2

in

las lui

Z

ll

S30

IB2 AM BSt

'8H

eafi

33D

Is

18S Iss

Js

1,740

Uk) £3 4§2

as:

42H

iiofl

40B

3S2 B4U

S

Ok Mo Sse

l.fflO 1,890

1,840

3a

io.o"

jj

B.7 A.7

is

Is

tl

g-V

3,7

n

Si

12,1

!i

7,0

ila

i:3

""3M'

i,aw

'f

*4i

Ml

,1

3G6

Iso

is

Hi

2t

O.Mt

0.411)

o.io3

3Ii.S

ilia

3. on

1M4

In Inrhraon" dialnsparvai

o.i4i am

".:

log 74 percent ol the dIflerFi Franklin .

cThedlKhBTgcsstlhb a grsphasad Interpolation.

dlfaDalthel7thuidl9

d-lwl discharge.

Forkut the "kink" is 74 per cent ol thatol the Fortymilt It Franklin Treek. Dally dlschanrPS at the "kink " were ( a dinibarge between the Fartymile at Steele tJreek and tl

iiilbrAug.l3-lS,lT-2l

Creek wereooiBi.im i.y Uk- t and the South Fork St by comparative hydro-

MixeUaruoui rru

tainremtnu in North Fort oj Fortymile, Riper drainage basi

in. 1910.

Date.

Stream and lnoallly.

Drataigo

Discharge.

PBrwjuul

Jul 16

North Fork ol Fortytnlks River above Slate North Fork ol Fortymilo River at "kink "

3q. miUi.

a.oi

'33G

1,11 '

.ft IB. 6

is.e

Sfc.i.

Champion CroekbBlowArkwmu Crook

Middle Fork of Fortymtto River at mouth

gSSW— Bull. 480-11 14

MINEBAl. llESOltHfES OF AU1BKA, 1910.

1!AGI,E DIMTItlCT-

Location Of Abea.

The Eagle district in this report is as the area draJnod by Mission Creek and its tribiitan<!s. It liis tii tho Eagle prociiict and the town of Eagle is tho ctiiiter of conuiierciul activity. It was topographically suireyeil in l8dS nod is covered by the map of th. Fortymile quadrangle.

aAOraO STATIONS AND UEASUBINa POIHTS.

\\'hicli gaging stations made in 1910 in tba

The following list giv<'.s -loturioiis at were miuntained or disiliur>;t' nmnsiirciniMitt Eagle district:

Gaging ttaiMm and measuring -point fn BagU dtiMet, i910.

Hurion Creek dnunagB bosm:

Huoon Creek above Colorado Oerk.

HuBon Creek above Amerkan Giix'k.

Ezceldor at mouth.

American Creek at claim "No. Sabuvu."

American Creek at United SUtet immpinK plant.

Discovery Fork of American Greek lii'low Sinr Gulch,

UBBION CBBEK DKAlKAaS BASIN.

Mission Creek drains a circiilai-shaped area of 170 square miles lying between Fortymile and Seventymile rivers. It enters the Yukon at the town of Eagle and has a length of about 30 miles. It flows generally northeastwtu-d to Excelsior Creek, where it makes a sharp turn and takes a southeastward course for 8 miles to its mouth. Its most southern waters rise at an elevation of about 4,000 feet in the divide at the head of O'Brien Creek, and its two largest tributaries from the west, Seward and Excelsior creeks, drain a portion of the eastern slope of Glacier Mountain, which reaches an elevation of 6,000 feet. Above Excelsior Creek the valley is bordered by high, precipitous slopes on either side. Below the big bend to the east the stream channel follows closely the northern part of the valley, which has a steep and narrow drainage slope to the north, whereas on the south the slope to the summit of the divide is verygradual.

American Creek is the largest tributary of Mission Creek and joins it from the south about a mile from the Yukon. It flows northeastward and is about 18 miles in length. Diseoven." Fork b its chief branch and enters American Creek about 8 miles from the head. Above Marion Creek, wliich is a small feeder from tiie east, the valley is sharply V-shaped and in some portions is almost canyon-

Wateb Supply Of Yukon-Tanana Beoion.

like, bung on either side by barren rocky slopes. Below Marion Creek the valley gradually broadens until it finally loses its identity in the Mission Creek Flats. The average grade through that portion in which mining has been carried on is about 125 feet to the mile, llie total fall from the head to the mouth is about 2,000 feet.

Wolf Creek b tributar>' from the south about halfway between American and Excelsior creeks.

Spruce is the prevailing timber. An abundant supply is available for fuel, and in the Mission Creek valley considerable quantities of a size suitable for saw logs are to be found.

Dailji ditchargt, i

Itay.

Ju...

July.

Aug.

Tune.

Jul)'.

AuF.

Sejit.

3g

"LI l.S

ra

:?

a. 7

?:J

!:l

1:!

8:8

3.

a.s

iS

4.t

3.fi

A

L.—

it

'"

re dttermlued by comparative hydropsphs, but tli

UlNEItALi HESOUHfES OI" ALASKA, 1910. Daily dUrJtirgc, in neeund-feet, of Antencan Orrekjur 1910.

1 "

An.rrtaui at ctolm "Nn. Mniiove"(dnilneo rm.ai.l wiuarBinllw).

Amorloin st Unltail Binr

Jon..! July.

Aug. StpV

Joljr.

Aw,.

Sept.

Oct.

K

lis

a.0

it

S.B K.fl

e.B

11,4

lU

(*J

17. n

aw a?

S

7S

a

2t

Ml £7

au

in

w

w 3a

M

E

3:t

so

S

lui;---

B. B-

f

0,lfl

u.ais

Ib.U

D-um aTfl

ff

ZB.It

I1.W2

Run-nlt (cJepOi In 1w*h on dralnatte

" These 'iischargej are oujy approslmnie. MUeellaruxmt nwuuremenis in Mittian Creek drainage basin in 1910.

Streiini iind loailltj'.

.fnl.

Water Supply Of Yukon-Tanana Region. 213

Seventymile District. Location Of Akea.

The Seventymile district includes the area drained by Seventymile River and that lying to the north of the Seventymile and south of the Yukon. This district Ues entirely witliin the Eagle precinct, and Eagle is the supply point for the mines. The maps showing the area are those of the Forty mile and Circle quadrangles.

GAGINa STATIONS AND MEASUBINa POINTS.

The following list gives the locations at which gaging stations were maintained or discharge measurements made in 1910 in the Seventymile district:

Gating stations and measuring points in Seventymile district 1910.

Seventymile River drainage basin :

Seventymile River above Flume Creek.

Seventymile River at the falls.

Flume Creek one-fourth mile above mouth.

Flume Creek ditch near outlet.

Alder Creek at claim "No. 7 above.'*

Deep Creek at mouth.

Nugget Creek at mouth.

Granite Creek above forks.

Granite Creek below forks.

Barney Creek at ditch intake.

Barney Creek at mouth.

Sonickson Creek at ditch intake.

Sonickson Creek ditch at outlet.

Mogul Creek at mouth.

Crooked Creek below Eldorado Creek.

Bryant Creek 2 miles above mouth. Washington Creek drainage basin:

Washington Creek below forks.

Seventtmtle Biveb Drainage Basin.

Seventymile River has its source in a relatively high and rugged divide east of Charley River. It flows east for about 60 miles to a point 4 miles from its mouth, where it makes a rightangle turn and flows north, joining Yukon River a])out 20 miles below Eagle. The drainage area is 667 square miles and is extremely imsymmetrical with respect to the river valley, as over three-fourths of it lies to the south.

The principal tributaries from the south, beginning with the headwat-ers, are Diamond Fork, Flume, Alder, Granite, Green, Sonickson, Mogul, and Bryant creeks. From tlie north Barney, Washington, and Crooked creeks are the principal streams, although much smaller than those from the south.

14 MINERAL HESOtntCKS OF AI,ASKA,, 1910.

Extensive liench formations occur tliroughout the Seventyrnils Valley. Above the fiiUa, wliich are located about on&-half milp bekiw Washington Creek, the river flows through a rather bromi gravelly flood plain, but below the falls it is more closely confintHl ant! along a considerable part of its course has cut a rock canyon 20 to 30 feet deep. At the falls the river hna a drop of about 9 feet in a horizontal distance of less than 200 feet. From Forit to the mouth, a distance of 53 miles following the general trend of tlio vallev, the river has a fall of over 2,000 feet. Fnim Diamond Fork

to Barney Creek the river 1,400 ieH in 25 milcw and from Flume Creek to Barney Creek there is a drop of 600 feet in 15 miles.

Daily durhirrge. in ta-imd-fffi, o/ SrvmlymiU Hitrjor ISlil.

ecvHIIymlle atrc

July.

Aug.

Bqil.

Oct

June. Jnly.

\v.

.

i.i: ia

Its

(l

iw m

3.2M

i.aoo

Im

m

3U

Ml

am

an aus

m

K

21

4. mi

Im)

MO Mi

aw sea

'b33

sao

Sm Ms

'"

m

SiS

S2

1,Kw

sm

4W

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Water Supply Of Yukon-Tanana Region. 215

Daily ducharge, in stand-feel, o/ Flume and Alder creettfnr 1910.

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S16 Mineral Behour(.'Ks 01' Alaska, 1910.

Daily diieharge, in second-, of Barnry. Sonirkttin. and Cmatrd meit for 1910.

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MUcellanenut maigurcmenis in SeiienlgmiU Rircr drainage baton 11

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Water Supply Of Yukon-Tanana Region. 21 Y

Washington Cb£Ee: Dbainage Basin.

Washington Creek rises in the divide north of the Seventymile and flows northward for about 25 miles to its junction with the Yukon. At the head the basin is about 18 miles wide and is drained by several large tributaries which reach from Barney Creek on the east to a point about opposite Flume Creek on the west. Ten miles below the head the basin is abruptly contracted to a width of about 6 miles and it averages about that width to the mouth. The headwaters flow through broad valleys, which have gentle slopes rising to a uniform altitude of about 3,000 feet. The drainage area above the mouth is 190 square miles.

Just below the junction of two small feeders which form tlie' headwaters of the main stream and rise in the divide at the west of Barney Creek, a measurement was made August 31 to determine the quantity of water on that day available for diversion over the divide to be used for hydrauUcking on Pleasant Creek, which is a small stream entering Seventymile River from the north just above Barney Creek. No accurate survey had been made, and it is doubtful if water could be carried over the divide in a ditch with the intake below the forks. It was difficult to obtain an accurate measurement because the stream flows through a flat, swampy area in a deep-cut channel with overhanging muck banks. A discharge of 0.78 secondfoot was recorded.

IINEltAL RESOURCES OF THE BONNIFIELD REGION,

k

By Stephen R. Capps.

16 ron covered by tliis report lies on the nortii slope of the Alaska Range between Nenana and Delta rivera, and in a general waj' is limited on the south by the crest of the range and on the north by the Tanana Flats. It therefore fomis a belt about 30 mites wide and 110 miles long, extending from Nenana River eastward to the Delta. That portion between Nenana and Little Delta rivers hag been \viilely known as the Bonnifield region, which is here considered to extend eastward to Delta River, Since the establishment of Faii- ' banks as an important mining camp the arpa south of the Tanana J has been visited by large numbers of prospectors, and although no strikes of exceptional richness have been made placer gold is widely distributed and has been found in paying quantities on a number of [ creeks. Fm-ther attention has been to tliis region by the- J extensive fields of lignite, by reports of large lioiiics of low-grade - beanng ore, and by the possibilities of profitably developing some of the great gravel benches which carry a low content of placer gold.

The western border of this area was visited iir 1902 by Alfred H. Brooks ' and L. M. Printlle, the results of their work being embodied in a report now in press. In 1906 Prindle again visited that part of the area lying between Nenana and Wood rivers, and a brief account of his work has been published.' The notes, traverses, and manuscript of both of these investigators have been freely drawn upon by the present writer, who has also been greatly aided by them in personal conferences in the oitice. The oianization of the field party and its itinerary are discussed on page 1 1 of this volume.

General Description Of The Region.

OEOaBAFHIC FEATTJBEB.

The region bounded by Nenana, Tanana, and Delta rivers may be divided into three distinct eastweat belts of different topographic character. On the north the Tanana Flats extend from Tanana River to the footliUls. As Tanana River makes a broad loop north-

1 Brooks, A. H., uail rrlndle, L. IS.. Th Uount UcKiolej' region, Abslcu: Prof. Papn C. 8. OmL Burver N'o. 70, 1B11. Prindlt, L. U., Bull. U. S. Oral. Survey Ho. 31-1, 1907, pp. 205-2%.

Mineral Resoxtbces Of Bonnifield Region. 219

ward between the mouths of Nenana and Delta rivers, this flat is of varying width, being about 30 miles wide along the Nenana, 50 miles south of Fairbanks, and 20 miles on the west side of Delta River. This great lowland area is of slight relief, broken only by a few isolated hills which rise above the general level of the plain. Most of it is heavily timbered with spruce, and the drainage is so poorly developed that numerous lakes and marshes make summer travel over the greater portion of it impossible. Along its southern edge the Tanana lowland ends abruptly, giving place to a belt of foothills which stretch southward from 15 to 20 miles beyond the flats. These hills form minor east-west ranges parallel to the higher mountains to the south and have for the most part rounded summits and long connecting ridges of smooth outlines, ranging in elevation from 2,500 to 3,500 feet, although here and there hills with somewhat sharper peaks rise to heights of 4,000 or 5,000 feet. Between the ranges of hills there are in places broad structural valleys. The tliird belt comprises the rugged mountains of the Alaska Range, which here trends nearly east and west, and though not so high as that part west of the Nenana its loftier peaks are snow covered and support vigorous glaciers. The highest peak in this region. Mount Hayes, with an altitude of 13,800 feet, is a conspicuous landmark through much of the Tanana country. (See PI. X.)

The drainage throughout the region is tributary to the Tanana. The larger streams rising in the higher ranges and flowing southward cut transversely across the foothill ranges, in many places with deep, narrow canyons, but many of the streams from the foothills follow the east-west transverse valleys to join the larger north-south streams. The most important streams of the area, from west to east, are Nenana River, Totatlanika and Tatlanika creeks. Wood and Little Delta rivers, Delta Creek, and Delta River. Only those streams of considerable volume maintain definite channels to the Tanana, the smaller creeks being absorbed by the flats, which are drained by irregular swampy streams.

As supplies can be transported to the hills much more cheaply by sledding in the winter than by trail in summer, few trails have been built in this region. An old Indian trail from the Tanana up the Nenana has been cut out and widened, but numerous forest fires during the summer of 1910 were followed by the falling of the timber, and much of this trail is now obliterated. A trail from the mouth of Wood River to the diggings on Tatlanika and Gold King creeks is passable during the summer months, and a good winter road from Gold King Creek to Fairbanks has been chopped out. Another feasible route to Dry Creek and Wood River follows the military winter road from Washburn across the flats and then swings southwest over the bare ridges. A fourth route, but little used, leaves the

220 Mikebal Be80Ubcb8 Of Alaska Wb

Valdez-Fairbanks road near Donnrily's and foUowB tha low hills westward. Fairbanks and Tanana Biver points form the base of supplies for the region, and the greater part of the expense of freighting is usually incurred between the river and the creeks.

Horse feed is found nearly everywhere m the summer months, either along the stream valleys or in the heads of the small draws above timber, which commonly grows to an elevation of 2,000 to 2,500 feet.

OBXERAL OBOLOaY.

Hie geologic formations represented in the ron ineluae an old sdiisC series composed of metamorphosed sedimentary rocks and anotlildr schist series of igneous rocks, both havilig beeflrbut by large bodies of intrusives; much younger deposits of cemented and somewhat folded beds; high bendi gravels but little deformed; and more recent glacial and alluvial depomts. The old schists formed from metamorjdiosed sediments compose the greater part of the main range of mountains. They consist for the most part of quartz-mica schists with quartzites, cherts, and carbonaceous schists. Large bodies of granitic rocks have in places been infooded into these schists, and other varieties of igneous. intruSEves liave been injected into and metamorphosed with the sediments in an intricate way. This series has been called the Birch Creek lacliist. The second schist series of altered igneous rocks forms the more important of the foothill ranges. It contains some sedimentary material, however, so that the two schist series in places show such intergradations that the boundaries are difficult to establish. Quartzfeldspar schists are the prevailing type, the rock being porphyritic over considerable areas, the feldspars occurring as conspicuous crystals with characteristic boundaries. These feldspars in places are over 2 inches in diameter, and many slopes are covered with crystals which have weathered out of the matrix.

Unconformably overlying the scliists and occupying shallow warped basins between schist ridges are areas of Tertiary sediments consisting of slightly cemented sands and clays and beds of lignitic coal. The coal-bearing series when first deposited doubtless covered a much wider area than it does now. It probably covered all or nearly all of the foothill belt and may even now underlie large areas of the Tanana Flats. The beds var\' in attitude from a nearly horizontal position to dips approaching the veilical, but in general occupy basins in the schists, the coal series dipping away from the bordering schists toward the centers of the basins. Overlying the coal series is a thick deposit of gravels, which is evidently of considerably later age than the coal series but which locally seems to bo structurally continuous with it. The gravels have a total thickness of at least 1,500 feet and are in general less folded and tilted than the

u. s. ai

S

Mineral Resources Of Bonnifield Region. 221

coal beds. They, too, were formerly much more widespread than now, as is shown by the remnants of the beds and by scattered gi-avels over the tops of many of the footliill ranges. Still later in age than the high gravels are the glacial moraines and terraces and, latest of all, the extensive gravel deposits of the present streams.

MINERAL llESOURCES. GOLD PLACERS.

General Descriition.

The locations in which placer gold in paying quantities has been foimd all lie in the foothill bolt between the Tanana Flats and the high schist range to the south (See PI. X.) Furthermore, the pla(!ers all occur in the valleys of the smaller streams wliich were either north of the area invaded hv ice at the time of the maximum glaciation or which were themselves not occupied by glaciers. It may be that formerly there was a concentration of gold m the valleys of the main range, but if so this gold was removed by the ice and scattered tliroughout the moraine deposits, and postglacial erosion has been insufficient to reconcentrate it or to form new placers in its stead. Colors can be found in almost all the streams of the footliills, but gold in paying quantities has so far not been foimd between Little Delta and Delta rivers. The streams between Wood and Nenana rivers are peculiar in that in their northward course from the liigh mountains to the Tanana Flats they cross one or two, and one of them four, hardrock ridges into which they have cut deep canyons with steep rock walls. Between the canyons the valleys widen out and have developed broad gravel floors. Wide areas in the footliill belt are occupied by liigli bench gravels, and scattered gravels on the crests of many of the schist ridges give strong evidence that the high gravels formerly covered all of this area north of the main range. All the workable placers have been found in the streams wliich have cut their valleys into these gi'avols or which drain areas formerly gravel covered. The high gravels have in many places been shown to carry a small amount of placer gold, and doubtless most of the present placer deposits have been derived from a reconcentration of the gold from these high gravels, although some gold may have been contained in the Tertiary beds and upon their erosion may have been reconcentrated along with that from the high gravels, and some may have been derived directly from the weathering of the scliists.

With the exception of Moose Creek, a tributary of the Nenana, on which pay was first found in 1909, the list of producing creeks is much the same as it was when visited by Prindle in 1906, and the total number of men engaged in mining or prospecting is smaller than at that time. The creeks wliich were producing during the last season

S32 MINBfiAIj BEBOUBCfSS OT iTJMTi) ttU, "t-

ue Moose, Totatlanika and its tribntanM (HomwtAe, Cilifomia, and Rex), two tributaries to Tatlanika from dw east (Gnibetake and Roosvdt), Gold King, and Port-age creeks.

MOOaS OHEBS.

Moose Creek is a small tributary of the Nenana from the east, joining that rirer about 10 milea above the Tanana Elats. It heads in a rounded schist ridge which was. once cped hy high graveb, and some remnants of these gravels still remain. Tha stream in its upper course occupies a valley cut in the stdusts, then cuts throoi beds of the coal-bearing series, below which it (mcr'ji's npun tlic- (ivclty flats of the Nenana. The first pioductim) .>l 'niisL>(|ut.'iicc from tliis creek was in 1909, when it was reported.1 lUO ounros of gold wus recovered during the last three weeks cif tlie suaBon, the pay being taken from a gravel bench with sdiist bedrock. It seems probaltlo that the gold is a reconcentration &om the high gravcU which onc( covered the schist but most of which have now hecu remove'd by etomxa.. Seven men are rrarted to have been during 1910. '

TOTATUXmU BASCr.

TotaOmika OMib.— IVttatlanika Oeek is a stream <rf eooiidardde size which enters the Tsnana Flats about 16 miles east of the Nenana. It drains a basin in the liills about 275 square milea in area. It is formed by the confluence of a number of creeks which head in the high schist ridge north of Healy Fork. Below their confluence the stream flows through a succession of rock canyons and broad, open areas, the floor being narrow and difficult to travel in the canyons on account of the swift current of the stream, the steep rocky walls against wliich the stream cuts on one side or the other, and the accumulations of large bowlders and coarse blocky talus from the walls above. In the more o])en spaces between the canyons the valley floor widens, having a breadth of several huntlred feet in places, and is composed of cobbles, fine gravels, and sands. The more important tributaries which join the main stream are Homestake, Buzzard, and California creeks below its junction with Rex Creek.

During the last six years a large number of men, encouraged by colors which can be found in almost all parts of the valley, have prospected along this stream from its head to the mouth of the lower canyon, and most of it has been staked during this period. Especially in the canyons where the gravels are shallowest are to be seen numerous old prospect pits and cuts. During 1910 all attempts to work ground on this stream hud been abandoned except oh a single claim, 2 miles below the mouth of Homestake Creek, where five men were engaged in mining. It is reported that the ground worked was yielding considerably more than wages.

Mineral. Besoubces Of Bonnifield Region. 223

There is abundant water for mining throughout this valley. In fact, the labor required in building wing dams and bedrock drains makes prospecting expensive even in periods of moderate run-off, and in times of high water the control of the stream is a serious problem to the prospector.

HomestaJce Creek, — Homestake Creek is a small tributary of the Totatlanika from the southwest and joins that stream in its upper canyon. Owing to the custom common among prospectors of giving diflFerent names to different parts of the same stream, the lower portion of tliis tributary is called Homestake and the upper portion Piatt Creek. It heads in a broad, rolling depression bordered by schist ridges which extends between the Nenana and the head of Tatlanika Creek. This basin is underlain by unconsolidated beds of sands, clay, gravel, and lignite. Two miles below its source it leaves the open country to enter a narrow, steep-walled canyon through andesite mountains, broadening agam somewhat before it joins the Totatlanika.

This valley has been prospected throughout its length, but workable placers have been found only in the canyon and in the open part of the valley just above it. Here mining has been in progress since 1906. The gravels are about 6 feet deep and lie on a decayed schist bedrock. The values occur in a well-defined pay streak 30 to 60 feet wide carrying reported values of about $3 to the cubic yard, the gold being found either on bedrock or in thin beds of oxidized yellowish gravels and sands. The ground being worked at the time of the writer's visit evidently received its gold from a small tributary which enters at that point. The gold is somewhat rusty and rather coarse, numerous pieces valued at $3 to $5 having been found. The greatest drawback to mining this ground is the scant water supply, less than a sluice head being available through the summer, so that it is necessary to hold the water with a dam until enough has accumulated to give a good volume for groundsluicing and to supply the sluice boxes.

In the canyon of Homestake Oeek, below the mouth of a small tributary called Ptarmigan Creek, three men were engaged in mining, having been at work on this ground since 1906 with the exception of the season of 1908. Here the gravels average about 6 feet deep and lie on either a schist or an andesite bedrock. The values occur in a pay streak about 25 feet wide, and the gravels are reported to yield from $3 to $9 per square yard of bedrock. A sluice head or more of water is available for a season of about 80 days.

From the character of the gold and its distribution it seems probable that it has been derived from deposits of high gravels, most of which have now been removed by erosion.

224 MINBBAIi BESOUSrKii OF ALASKA, IQID.

It is estimated that the total pnxiiic-tioti of Ilompslake anil Piatt creeks from 1906 to 1909, inclusive, has bft'ii about $50,000.

(Mifomia Greek. — California Creok, wiijcli joins tJie Totatlaiuka at Ute head of its lower canyon, drains a considerable area iii tlie vicinity of Jumbo Dome and htis developed two canyons at puiiiU where it crosses schist ridges, tf ost of its course, liowever. is tbrouli a broad open country of rounded hills of gravels, sands, and liiinite beds. Colors can be found in many of tlie basin of tliiti stream, althou no information was obtained of gold having beeu produced in commercial quantities. During the season of being done in but a single locality at tlio head of a (anyon some 5 miles above the junction of Cidifoniia Creek witli Rox Creek. Hero two men had constructed a bedrock drain, in gi'avels about G feet deep lying upon a schist bedrock. At tJie time of visit the gold content of the gravels had not yet been determined, tliougli pamiing tests seemed to show fur values.

Rex Creek. — Prospecting on Rex Creek has been carried on intei mittmily nnce 1905 by a number of men with but indifFerent success. Thei creek, a tributary of tlie Totatlonika, heads in schist hiUs, some of which still have a portion of their ancient gravel capping. .Some of its tributaries have sluu-p V-sliaped valjpys cut into the schist, but Ute valley of the main stream i.s broad and in its lower reaches lies in beds of sands, clay, and white quartz gravel, with some beds of lignite which are thought to correspond with the base of the Tertiary as exposed in Ilealy Creek.

Botli the gravels of the main stream and the low bordering bench gravels carry gold which is in places sufficiently concentrated to yield good pay. The values, however, are unevenly distributed, especially on the benches, and no well-defined continuous jiay streak has been found on them. In the main stream tlie difficulties of securing proper drainage have prevented thorough prospecting. The water supply on upper Rex Creek is too small for extensive workings, between one and two sluice leads being available during the summer.

The ground worked ranges up to 6 or 8 feet in depth, the pay all being found close to bedrock, which consists of decayed schist and into wliich the gold has penetrated to a depth of about a foot. The gold is bright and fairly coarse, and the gravels contain no bowlders too large to handle.

Tatlanika Basin.

TatlaniJca Creek. — Tatlanika Creek drains an area east of the basin of the Totatlanika, the streams being miles apart where they reach the Tanana Flats. It is formed by the union of Sheep and Last Chance creeks, both of winch head well back in the liigh mountains. These streams on emerging from the main range cross areas of much

Minsbal Be80Ubces Of Bonnifieu> Region. 225

slighter relief, then enter gorges cut through quartz-feldspar schists, and below their junction enter a broad open basin in imconsolidated sands, clays, gravels, and some lignite, through which the stream has developed a gravel floor many hundreds of feet in width. The coalbearing series at this place is thought to be much younger than that occurring on California Creek. Through this broad basin the stream continues for more than 10 miles, abruptly entering another rock canyon from which it enters the gravel plain of the Tanana. In the basin above the lower canyon the Tatlanika receives tributaries from both the east and the west, those from the east being somewhat larger and having more deeply incised valleys. Three of the eastern tributaries. Grubstake, Roosevelt, and Hearst creeks, have yielded placer gold.

Grubstake Creek, — Mining has been carried on more or less continuously on Grubstake Creek since 1905, though only a few men have been employed there at any one time. The valley of the creek hes along the line where the high gravels join the schist ridge to the south and the basin includes portions of both the schist and the high gravel areas. Workable placers have been found only for a mile or two above the mouth of the stream, which has here cut a valley 200 to 300 feet deep through a wide gravel terrace into the beds of the underlying coal series. Where the stream gravels are worked they Ue on a soft bedrock of clay, sand, or coal, the pay being found in the lower foot or two of the gravels or on the bedrock. The pay streak varies from 25 to 75 feet in width, and the gold is flat, well worn, and rather fine, containing few coarse pieces. Though the gravels contain some bowlders of a large variety of rocks, derived both from the high gravels and from the schist, most of the material is small enough to be easily handled. About one sluice head only of water is available throughout the season, so that operations are restricted to open-cut workings. It is reported that in 1910 two men were mining on this creek in ground which yielded a satisfactory return.

Roosevelt Creek. — Roosevelt Creek joins the Tatlanika about 3 miles below the mouth of Grubstake Creek. It heads in a high ridge composed of unconsoUdated gravels, sands, and clays and has no hard bedrock within its basin. The workable placer ground lies in the lower 2 or 3 miles of the valley, which is here comparatively shallow and open, without high bordering ridges. The placer deposits occur in stream gravels suppUed by erosion of the liigh gravel covering of the ridge in which the stream heads, and the placer gold is doubtless the product of the reconcentration of gold from the same high gravel beds. In the absence of hard bedrock the gold is concentrated on a soft bedrock, consisting of clayey or sandy layers of the coal-bearing series into which the stream has cut its channel.

98319*— Bull. 480—11 15

326 MINERAL RESOURCES OF Al-.iSKA, 1810.

The ground workptl is sliaUow and tlip values ar obtained from a pay streak 20 to 60 widp. Tho gold is fliit and fine, and its worn appearance inditatHs that it has traveled far from its original source. An iiLsufTicient water supply has retarded development on thia creek, and the production for tlie last few years has been unimportant, Mining whs in progress at one place on a small scale during the seitMoii 1910.

Hearst Creek. — Hearst teek enters the Tatlanika from the east, a tittle more than a mile below the mouth of Roosevelt Creek, and also heads in the unconsolidated deposits, with the lower part of its valley cut into the sands and gravels of the coal-bearing series. In the absence of hard bedrock the gold has been concentrated iipOQ the more favorable of the unconsolidated beds. Sine* 1905 a feW' thousand dollars' worth of gold has been recovered from this valley' but no information be obtained of mining there during 1910,

Gold Kino Creek.

Gold King Creek in tlie first stream of imiMirtance east of the Tatlanika and flows through the footliill belt with a course somewtiat east of north to the Tanana Flats, in winch it joins Wood River, It hails in a high ridge of quarter-feldspar schists tlirough which it has eut a deep notch. From the achists it passes out into the area of liigl\ gravels, am! its valley 10 miles below its lieiid is incised 1,200 to 1,500 feet below the surface of the ridges to the east and west. These ridges were originally part of a gently sloping plain built up of gravels from the mountains to tJie north, and in many places portions of the original surface of thia plain are still preserved. The materials are for the most part well-washed gravels of moderate size, with some sandy and clayey beds, but some portions of the deposit contain bowlders as much as 2 feet or more in diameter. The bowlders and pebbles are all of rocka which can be recognized as having come from the ridges to the north. The stream was nowhere observed to have cut down into the coal-bearing series which probably underlies the gravels.

Mining has been carried on in the stream gravels of Gold King Creek since 1003. The ground worked hiis ranged in depth from 2 to 8 feet, the principal drawback being the presence of many large bowlders, derived both from the rocks at the head of the valley and from the high gravels. The natural tendency for a stream cutting through gravel beds is to concentrate the large bowlders as well as the heavy metallic contents in the stream channel, the liner and lighter material being carried away. Water is iisually .sullicient for small mining operations, three or more sluice heads being available even in periods of low water, and in wet seasons tlie flow of the stream is large. The gold is said to assay $17.82 an ounce and is flat, wall

Mineral Besoubces Of Bonnifield Begion. 227

worn, and rather fine. It is found either in the stream gravels or on a soft clayey bedrock. In 1910 mining operations were conducted on two claims, Nos. 19 and 21 below Discovery, and the yield at both places was reported to be satisfactory.

In the valley of GM King Creek, as well as at a number of points in adjacent creeks, large areas of groimd have been staked by those who iateud to mine the extensive deposits of high bench gravels into which the stream valleys are cut and wliich cover a wide area all along the foothill belt iu this region. These gravels in the valley of Gold Creek are more thau 1,000 feet in thickness and no facts are known as to their depth in the valley bottom. For a number of years these high gravels have been known to be gold bearing, and from them many of the producing placers have been derived by stream concentration. Reports of men who have prospected in different parts of the liigh-gravel area show their gold content to range from fine colors to 3, 5, and even 15 or 20 cents to the cubic yard. The lower returns are usually from the gravels near the tops of the ridges, and the higher values have been found along the lower slopes. This fact is significant and probably indicates that the values in the richer groimd have come from a concentration by erosion from the gravels above rather than that the actual gold content of the gravels increases as the deeper-lying beds are reached. Further evidence of the low average content of the high gravels can be obtained by comparing the amount of material eroded in those valleys which lie wholly within the area occupied by these gravels and the richness of the placers in these valleys. Although some of the gold derived from the high gravels might well be expected to have moved on down these streams, yet if the original gravels carried any considerable values it would be expected that the present stream gravels would be much richer than developments have so far proved them to be. Great care should therefore be exercised when prospecting the high gravels to drive tunnels far enough into the deposits to reach undisturbed beds which have certainly not been enriched by gold from above. Only by careful sampling in this way can the actual gold content of the beds be determined.

By far the largest project under way in the Bonnifield regicm, and one wliich may have a most important influence upon its future development, is that of the Berry & Hamil Co., wliich is making preparations to mine on a large scale the liigh gravels in wliich the basins of Gold King and Bonnifield creeks have been eroded. The company controls a large acreage of land in these two valleys. No mining has so far been done, but during the last summer 45 men were employed in building ditches and roads, erecting buildings, etc. It was expected that the ditches would be completed during the suifmier so that active work might be commenced early

[

228 MINEBAI. RE&OITRCES OF AlSKA, ISIO.

in the spriiig of 1911. The ditches include one 2i miles long and QUO 2 miles long, to take water from the leads of Mystic and Moose creeks, respectively, and drop it into the upper end of the Gold King drainage basin; another, 6i miles long, to take the water from upper Gold King Creek to tli© on elaim No. S below Discovery; and a fourth, a little more than a mile long, from Gold King to the cut. The long ditch, which is to supply water under pressure for the hydraulic giants, will carry 3,000 miner's inches of water and will give ft head of 700 feet at the cut. This is more pressure than will be needed, but the ditch has been so laid out that its continuation will cross the riiige into the Bomiifield basin and will furnish sufficient water for operations on both streams. Tlio giants, with 4-inch nozzles, have been set, and the cut opened so that sluicing may be begun without delay. The timber for flumes, sluice boxes, llniilding, etc., is sawed at the company's 'mill located some miles below the mine workings. Most of the upper portion of the valley fe timberless. So far as could be learned on the ground it appears ih&t the deposit to be worked has not been extensively prcspecUvl, aud its gold content can be accurately known only when some conuderable body of it ha-s been sluiced. Conditions should be favorabiit here for the hatidling of ground at a very low cost per cubic yard, as a very high gravel face will bo had when the cut is run back into the hill a few hundreil feet. Fiirthornion'. although suiiu' larjre bowlders occur in the gravels, most of the material is fine enough to be readily handled with the giants, and with the high pressure available it is largely a question of water supply. If the ground proves to be rich enough to warrant it mining will be established on a permanent basis in this region, as the gravels are practically inexhaustible and are so widely distributed that the water from a large number of streams could bo used in their exploitation.

DUV CREEK (little DELTA DRAINAGE).

Dry Creek heads in the high scliist mountains and flows north to the Xanana Flats, draining a basin wluch lies just east of that of Wood River, In the foothills the stream has a largo volume of water, but much of its water is said to sink into the gravels and disappear soon after reaching the flats. Above the mouth of Newman Creek, its largest tributary' from the east, the valley is cut into schists. Below Newman Creek, for a distance of 5 miles, the stream flows through a wide valley cut tlu'ough high gravels into the coal-bearing formation, then enters a schist canyon through which it flows for about 5 miles, eyeing into the broad, flat valley of the Tanana.

The stream gravels of Dry Creek are known to carry gold, and the valley floor has been staked for a few miles above the mouth of Newman Creek and considerable prospecting done. The gravels are trom

Minebal Resoubces Of Bonnifield Region. 229

4 to 8 feet deep and lie upon schist bedrock. Pay as high as $3.50 per square yard of bedrock has been found, but large bowlders are numerous and the ground proved too wet to work without establishing a bedrock drain, an undertaking which has so far discouraged the owners.

Caribou Creek, a tributary of Dry Creek from the west about 7 miles below the mouth of Newman Creek, flows through a valley wliich is in high gravels at its head but in schist in its lower portion. In 1909 two men made fair wages by working the stream gravels, but the ground appears not to have been rich enough to encourage them to return, and no work was done on this stream during 1910.

Newman Creek drains a basin which includes schists, the coalbearing series, and high gravels. The stream gravels carry some gold, and the high gravel hills are also auriferous, reported prospects from the upper beds of the high gravels showing a yield of 3 or 4 cents a cubic yard, with values increasing somewhat in the lower beds. At the base of the high gravels, which are similar to those already described for Gold King Creek (pp. 226-228), there is abed of clean rounded white quartz pebbles, locally known as the ''white channel/' on which there seems to be some concentration of gold. Newman Creek hafi so far not produced gold in commercial quantities, but a project is under way to exploit the high gravels on a large scale. One party has staked 125 association claims of 120 acres each in the basins of Newman Creek and West Fork of Little Delta River, water for hydraulicking to be taken from the latter stream. It was expected that the ditch would be surveyed during September, 1910, and active construction started in the spring of 1911.

Portage Creek is a small tributary of West Fork of Little Delta River and has a basin in the high gravels east of the head of Newman Creek. Placer mining of the stream gravels has been carried on continuously for the last five years by one outfit, the pay being concentrated on a clay bedrock. No hard bedrock occurs in this gulch. The total production of the creek to date is estimated at $10,000.

Lode Minino.

The wide distribution of placer gold in the Bonnifield region lias attracted the attention of many prospectors to the search for placer mines, yet comparatively few men have been seriously engaged in the search for the lodes that must have furnished the gold to the gravels. Both the geologic and the physiographic evidence at hand point to the high schist moimtains of the Alaska Range as having been the ultimate source of the gold, and these mountains hold forth considerable promise to the hard-rock prospector. Associated with the schists of the main range which have been correlated with the Birch Creek schist of the Fairbanks region, and also cutting the quartz-feldspar

p

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180 MINEHAL RESOURCES OF AlASKA, 1910.

BchietB to tlie nortli, are many intrusive granitic rocks, and there is some 1'ea.soii to believe that tlie luiueralization of the schists ra&y be due to tiiese intrusions. The schists in tlie neighborhood of such granite and diorita masses are therefore the most promising tiehls for tlio search for mineral-bearing lodes. Lode prospecting lins so far been confinetl largely to the basin of Wood lliver.

Chute Creek.

Chute Ci"eok is a tributary of Wood River from the east. It is 5 or 6 miles lung and flows in a deep narrow-bottomed gorge through a complex series of scliists cut by intmsives. In 1908 a certain zone of the schist series was discovered by J. C. Rogers, a prospector, to he considerably mineralized with iron pyrite and to carry gold values. Tlie lodo is an altered igneous rock wliich weathers to conspicuous red and yellow colors and is witli extremely small cubes of finely diasomiuated pyrite. The mineralization wos observed to occur in a zone which has a width of over 100 feet, striking nearly north and south, and which has a high dip, so that alarge body of pyritized rock is exposed. The same rock, or a very similar one, occurs in the valleys of Sheep Creek to the south ami of Dry Creek to the east. In 1009 a 3-stamp mUl was installed on Chute Creek and operated for about a month. In August of that year the mill wag wa.shed out by a frc'sli*'t iiTid ithiiH since been removed to jinrt of Ihecoiiulry. A 30-foot tunnel driven this year into the ore body shows no changes in tlie rock other than those due to protection from surface weathering.

The owners report that assays show a yield of $5 in free gold and $4 in concentrates.' The rock milled is also reported to have carried values of about $9 a ton. Assays of similar rocks from Chute, Sheep, and Dry creeks all showed traces of gold, though no attempt was made to sample any ore body. If further tests prove the average gold content of this mineralized zone to bo anywhere nearly equal to the values reported, there is here an opportunity to develop mines in which the lai-go supply of ore and the favorable conditions for mining should allow a liberal margin of profit over the cost of production. A rather good grade of lignite coal could be procured for power within 5 miles of the ore croppings.

Kansas Creek,

Kansas Creek is one of the larger tributaries of Wood River from the east. In its basin, as well as in that of Co]>per Creek, which enters opposite Kansas Creek fnim the west, bodies of a black quartzitic rock which are reported to carry gold values are associated with the schists. The only development work which has been done in these

resources ot Alsska— Raport on piOEiesa of loves tigattooa In IM: BolL

Mineral Besoubcbs Op Bonnipield Region. 281

bodies is on Kansas Creek, where, it is reported, a 90-foot tunnel has been driven into such a black quartzitic bed, which shows disseminated pyrite. No report of the assay value of this rock was obtained.

Coal Deposits. General Description.

The coal-bearing rocks referred to frequently in the preceding pages occupy a large area in the foothills north of the main range. They have their greatest known development and offer the best exposures on the western edge of the area under discussion and were visited as far eastward as Wood River and their approximate distribution mapped by L. M. Prindle in 1 906. ' During the summer of 1 910 further information was obtained regarding the areal extent of this important series, and numerous exposures were found which extend the limits of the formation eastward to the neighborhood of Delta River. Report from prospectors also show that coal, probably of the same age, occurs both east of the Delta and west of the Nenana, so that further investigation may extend this field both east and west much beyond its limits as now known. It also seems highly probable that the coal series underlies parts of the areas of high gravels and of the Tanana Flats. From the facts now known no estimates can be made of the possible coal resources in the region where the formation is completely covered by later deposits, as the coal beds may there he too far below the surface to be economically available, and the large supply of more easily accessible coal will certainly be used before an attempt is made to use that which is more deeply buried.

The coal-bearing beds, where best known, he in low troughlike areas between the east-west ridges of schists which form the foothills. The series consists of sands, clays, gravels, and coal, the beds being in general but slightly cemented. The base of the series is composed of beds of pebbles and angular or partly rounded bits of quartz in a matrix of white sandy clay, or of kaolinic material, which where exposed is conspicuous for it whiteness. This is succeeded by alternating sands, clays, and coal, the coal beds being in general thicker toward the base of the series and becoming thinner toward its top. One section shows an aggregate of 230 feet of coal, of which over 200 feet is in beds 4 feet or more thick, and in other less complete exposures the total thickness of coal measured was in many places from 50 to 130 feet, single beds reaching thicknesses of 20, 30, or even 40 feet. In many places, too, certain of the coal beds have been burned out, leaving the adjacent beds burned to a bright tile-red. Where this has occurred, the beds just above are in places brecciated and much disturbed by caving down to fill the void left when the coal burned out. The red baked beds are much harder than the associated uncon-

232 Mineb.U, Eebources Of Alaska, 1910.

solidateii deposita and retained the imprints of fossil leaves which show the coal series to be of Tertiary age.

The coal or more properly lignite beds of the Kenai formation vary considerably in character, being firm and compact and commonly very thick lignite beds near the base of the section but becoming thinner and more woody aa the upper beds are reached. No openings were seen which would give an opportunity to collect fresh unweathered samples for analysis, but the surface croppinga of the lower beds furnish a fuel wliich has had some small local use and wliich is said to burn freely and without much ash. Though probably of too low ft grade to ever compete with the better coals of the coast for export, it woulil find a ready market for use in the interior of the Territory. It also offers exceptional opportunities for the development of power in the coal fields for electrical transmission to points in the Tanan& Valley. Fairbanks is less than 60 miles from the nearest of these fields and well within the zone of economical transmission.

A heavy series of gravel beds overlies the Kenai formation at many points and was probably once continuous over much of the foothill area, but erosion has now removed tlie gravels in many places where their former piesence is shown only small patches or by scattered pebbles. The exact stratigraphic position of tliis gravel series is still in doubt and can be detei-mined only by more detailed investigation. No dcterniinahle fosils have so far boon found in it. It seems to be distinctly older than the glacial deposits and occurs at elevations above those reached by the ice at its greatest development, being folded and tilted more than the Pleistocene deposits. Near the Nenana it seems to be structurally conformable and continuous with the top of the coal-bearing beds and was thought by Prindle to be a continuation of the Kenai formation. At points farther east, however, it seems to overlie the Kenai unconformably, and the writer is disposed to think that an erosion interval elapsed after the Kenai before the high gravels were laid down. It is possible, however, that different conditions existed in different localities and that the gravels may be continuous and conformable with the coal-bearing beds in some places and unconformable in others.

Local Descriptions.

Healy Creek. — The valley of Ilealy Creek is occupied by the coal formation for about 10 miles above its mouth. In a general way these beds form a synclinal trough with its axis parallel to the valley. The stream follows the trough of the sjTicline in its upper end, but lower down it crosses some of the beds. The deposits lie in a basin in the schists, upon which they rest unconfoimably on both limbs o[ the basin, the dips of the coal beds ranging from vertical in a few places to horizontal at the bottom of the trough. Near the east end

Mikebal Besoubces Of Bonnifield Beoiok. 288

of the coal basin Healy Creek flows for more than a mile in the trough of a coal bed which forms the banks of the stream on both sides. The folded coal beds have suffered vigor*ous erosion both by streams and. by glacial ice and in upper Healy Creek much of the series has been removed. A measured section about 6 miles above the mouth of the stream shows a thickness of about 1,500 feet of these beds, and here the upper part of the series is missing. Near the mouth of the stream a carefully measured section gave over 1,900 feet of the coal series, with about 2,000 feet of the overlying gravels. The coal series may or may not be complete at this point. At the two places where measurements could best be made the total thickness of coal found was, in the section near the mouth of the creek, 230 feet in 23 beds, of which seven beds contain 174 feet of coal. A section 6 miles east of the above showed 130 feet of coal, of which four beds contain 80 feet. As some beds of coal have been burned out in almost all sections examined, the above measurements probably fall short of the original thickness.

Lignite Creek. — The Lignite Creek coal basin is separated from that of upper Healy Creek by a high schist ridge, but the two fields are probably continuous at these lower ends. It extends eastward beyond the head of Lignite Creek and includes areas at the headwaters of Totatlanika and Tatlanika creeks. In its eastern end exposures are few and poor, as the streams have made only shallow cuts into the beds, but sufficient outcrops of coal were seen to place most of the basin among the known coal-bearing areas. By far the best exposures are to be found in the valley of Lignite Creek and its tributaries, which have cut sharp, steep-sided valleys as much as 1,000 feet into the coal-bearing beds, without, however, anywhere exposing the imderlying schist in the center of the valley, so that the lower part of the series is not shown. The beds, Uke those in Healy Creek valley, he in a basin bordered by schist ridges and old intrusive rocks, the beds dipping away from either border toward the center of the valley. Although at some points along the borders the dips are high, being as much as 45° on the south side of Jumbo Dome, in general the coals of Lignite Creek Ue much flatter than those of Healy Creek, and through most of the valley they appear to the eye to be horizontal. The beds consist of cross-bedded sands, soft blue shales, some fine, loosely cemented conglomerates and gravel beds, and coal. In the deeper exposures the coal is hard and dense and the beds are heavy, but toward the upper beds the coals become woody and fibrous, with much shaly material, and the beds become successively thinner. As the coal series of lower Healy and Lignite creeks is overlain by a thick deposit of gravels, its actual areal distribution is much greater than is shown by a map of its surface occurrence.

B84

MINERAl. RESOIIECES OP JOASKA, 1910.

A section of the coal script's tncaBurcd by L. M. PriiKile, about 6 luUeH above the of IJite Creek, gives 129 feet of coal in a total thickness of 726 feet of beds. Of tliia more than 100 feet occurs in beds 8 feet or more tliick. Anottier, about 2 miles farther upstream, shows 48 foet of coal in a section 170 feet liigh. These two exposui-ea show only part of the whole series, and the total thickness of coal in the complete section is' doubtless much greater than that of either.

California Oreeh. — California Creek heads on the south side of Jumbo Dome, in the Lignite Creek coal field. North of this dome it flows through anotlier area underlain by the coal-bearing series, whicli crops at the surface over about 15 square miles. The beds here have the same structural relations us elsewhere, lying in a basin bordered by schist ridges and dipping toward the center of the basin. The dips, however, are gentle, and thi-ough much of the field the beds are nearly horizontal or lie in gentle wavelike swells. The streams have nowhere made deep cuts tliruugh the coal series, and the thickness seen is probably much less than the actual thickness, as there may be many coal beds below, no surface outcTOps of which were seen. The e.' of the field is also greater than the surface distribution, for along its western edge the coat beds are overlain by a heavy deposit of gravels. They are composed of santis, shales, and white kaolinic materials containing quartz fragnienl sand pebbles, and beds of lignitic coal. Along the main stream for several milea a heavy coal bed 12 feet thick shows in the stream bluffs, in places dipping below the stream bars but in general lying nearly flat. Other croppings of the same or a similar bed show in tributary valleys to the east, so that it is probable that the field contains at least 12 feet, and probably more, of coal throughout its area.

In the basin at the lower end of California and Rex creeks the beds of the coal series cover an area of about 20 square miles. In character they are similar to those on upper California Creek and are conspicuous for the prominent white bluffs exposed along Rex Creek and for a bright-ied color in many jtlaces where the coal has burned out and baked the adjacent beiis. Some woody coal was seen on a small tributary south of Rex Creek, but no workable coai beds are known in this basin.

TaUanika hasin.—Oa the east side of the Tatlanika Valley, in lower Grubstake Creek and between Ronscvelt and Hearst creeks, the clays, sands, and coal beds of the coal series outcrop, and it is reported that similar occur as far north as the head of the lower canyon of the Tatlanika. Little is known of tlie amount of coal present, although a bed 12 or 15 feet thick is said to outcrop at the surface, dipping at a low angle to the east. No development of the coal has been attempted here, but its occurrence is of interest,

Minebal Resoueces Of Bonnifieu) Eegion. 235

as it affords strong additional evidence that the area of high gravels is underlain by coal between Tatlanika and Wood rivers.

Wood River basin. — In the valley of Mystic Creek and westward to that of Moose Creek the coal-bearing beds have an area of about 7 square miles. One section shows 30 feet of coal in two beds, and at another point the upper 10 feet of a coal bed outcrops. The coal has here been used for cooking and heating in a camp of 25 men, with very satisfactory results. The total thickness of the series and of the contained coal beds is nowhere exposed.

At the head of Coal Creek, which joins Wood River 4 miles below the mouth of Mystic Creek, the coal series is exposed, dipping steeply from the schist ridge to pass beneath the high gravels north of Coal Creek. No opportunity was had to study this section closely, but some 16 coal beds were seen, the aggregate thickness of which will reach more than 100 feet. In the uplift and cnimpling of the beds the coals may have been given a greater thickness here than they possess farther to the north, but unquestionably there is a valuable coal field beneath the high gravels, concerning the extent of which we know Uttle.

Dry Creek basin. — In the valley of Dry Creek, at the mouth of Newman Creek, 140 feet of the coal series is exposed beneath the high gravels. Coal beds at this place have been on fire for at least five years and are still burning. Prospect holes and coal croppings, while giving Httle information in regard to the thickness of the coal beds, show that the series with workable coal beds lies beneath the high gravels on Dry Creek.

Isolated coal croppings in the basins of Little Delta River and Delta Creek also indicate that' the coal is widely distributed and may underlie large areas of the high gravels as far east as Delta River.

Gold Placer Miumg Developments In Toe Innoko-Iditauod Region.

By A. G. Maddren.

Although several of the pioneer American prospectors of int* Alaska are known to have and passed through p the Kuskokwim Valley as early as 1889, and others are i have visited the Innoko Valley as early as 1898, placer gold in pair quantities was not discovered in this part of Alaska until lOlM In the summer of tliat year gold was found on Ganes Creek, one c the principal headwaters of Innoko River, and since then a plac< camp, with an average population of 150 working miners, has bee maintained in the upper part of the Iiuioko Valley. (See i PI, XI.) A settlement named Ophir, situated on the mam riw at the mouth of Ophir Creek, has been the center of this community since the spring iif 190S, Tlie Jnimku district, in spite of many discouraging ciroumstiinces, due chiefly to its isolation and diffi culty of aeceas, hiis established itself as a worthy producer, and from 1908 to 1910, inclusive, its placer-gold output has totaled about $750,000. Tliis has served tn stimulate interest in the gold-' bearing possibilities of the stmuns which drain either side of th Kuskokwim Klountains and flow into Yukon and Kuskokwiia rivers. Up to the present time, however, the Innoko district has suffered from a chronic scarcity of both provisions and naxf ing equipment, and in consequence of the high costs that hart prevailed very few persons have felt justified in expending mudi time or money in prospecting the outlying parts of the district The result is that after three years very little is yet known aboilj the gold-bearing possibilities of a wide extent of country that it drained by the northeastern headwaters of the Innoko and tributaries of Nowitna and Kuskokwim rivers adjacent theresa Prospects of placer gold are reported to occur upon the hoadwaten of the Nowitna, a tributary to the Yukon that lies northeastward from the northeastern headwaters of the Lmoko, and upon thi Tuentna or Nixon Fork, tlio large nortlipnstern branch of thi Takotna, situated east of the upper Innoko, but no productive

t

/

.

Placer Mining In Innoko-Iditabod Region. 237

mining has been developed within these basins to date — in fact , no genuine prospecting has been done within them, although considerable wholesale locating of ground, especially in the Tuentna Valley, has been done by a few speculative individuals using powers of attorney in the unrestricted manner now practiced in Alaska.

Prospects of gold also occur on small streams that drain the northeast end of the Kaiyuh Mountains, which bound the west side of the Nowitna Valley. Several thousand dollars' worth of gold has been mined from a short gulch stream named Reeley Creek, tributary to the Yukon, opposite the mouth of Melozitna River.

Southwestward from the Innoko district more has been accomplished than toward the north and east. Some prospecting has been carried on at intervals since 1907 on eastern tributaries of Tolstoi Creek, a large branch of Dishna River, and it is said that fine colors of gold are so widely distributed within the deposits of the valleys of Madison and Mastodon creeks that prospects may be obtained at a iiumber of places. So far, however, no concentrations of Id of sufficient worth to pay to mine have been found on any orthe tributiaiies of Tolstoi Creek.

Since 1908 a Uttle prospecting and a great deal of locating have been done along both the northwest and southeast flanks of the Kuskokwim Mountains where they separate the headwaters of the Dishna and Iditarod, tributaries of the Innoko, from those of Takotna, Black, and George rivers, tributaries of the Kuskokwim. (See map, PI. XI.) During the winter of 1909-10 colors of gold were found on Deadwood Creek, a headwater of the southwest fork of the Dishna, and some open-cut pick and shovel work was done there in the spring of 1910 by several men but was soon discontinued because it did not prove profitable under present conditions. Extensive locations for placer mining have been made in this vicinity on Deadwood, St. Patrick, and other creeks tributary to the southwest fork of the Dishna and also across the divide at their heads to the south on July, Willow, and Moore creeks, which are headwaters of Takotna River, a tributary of the Kuskokwim. Very little work has been done on these locations — in fact, on most of them none at all. Moore Creek is the only one upon which gold in paying quantities has been found to date, but no production to speak of had been made there up to 1910. This general locality, however, appears to be worthy of careful prospecting.

In the later part of the summer of 1908 two prospectors, W. A. Dikeman and John Beaton, who had been to the Innoko district earUer in that year but were not encouraged by the outlook there, descended the Innoko in a small steamboat. Upon reaching the large southwestern branch of the Innoko, now named the Iditarod, these two men decided to explore that stream and prospect on its

238 MINERAL, HESOURCES OF AlASKA, 1910.

headwitters. Thpy asccaded the Iditiiroil as far as the low stage of water of that season would peniiit their lioat to go and there prepared for winter by building a log houe which has since been caUtwl "Discoverers' Cabin," This house is situated on the main rivet about 8 or 9 miles below the present town of Iditarod, or some 25 miles below the mouth of Otter Creek. During tlie early winter they sledded a prospecting outfit southward from their winter ] quarters across several low ranges of hills to Ottr Creek ami decided to look for gold in the valley of that stream at a point about 1 2 miles , above its mouth. Their choice of a location to prospect, decided upon at haphazard, as it was in midwinter, proved moat fortunate, ' for they were rewarded by finding gold at a depth of only about 13 feet in the first holes they dug to bedrock, the discovery being made on Christmas day, 1908. The discoverers then located a moderate J number of claims for about a mile along Otter Creek for themsclvea and a few friends.

Owing to the dlsttuice of Otter Creek from settlements or routes oi travel and to the fact that the discoverers were practically aloue information about the newly found pros|>ect8 of gold did not spread rapidly. It wa not until the summer of 1909 that other prospectors gathered there from the Innoko and Y.ukon districts. The result of their arrival wan I he locating of claims that covered practically all the valley Inmls nf Otter Cii'ck, its tributaries, and the tiiljiirent streams. Almost no mining was done during the summer of 1909 because of the lack of equipment and supplies. During the later part of this summer most of the several hundred people on the Iditarod were chiefly concerned with getting enough supplies at hand to enable them to remain through the coming winter. Considerable amounts of supplies that were sliipped to the new district did not arrive because Iditarod River was at a low stage during the open season of 1909 and navigation was closed by ice earlier than usual that autumn.

In spite of these handicaps some systematic prospecting of the claims on Otter Cieek was undertaken during the winter of 1909-10 and some gold was mined from small underground drifts. The reports about this work were either sent out in such optimistic form or became so magnified in transmission that a great deal of interest was aroused about the new district, with the result that when navigation opened on the Yukon in May, 1910, a couple of thousand people and a considerable amount of supplies and macliinery were bound for the Iditarod. Until the middle of July the traffic to the new camp taxed the capacity of the available steamboat transportation on the Yukon and for a time the movement to reach the proportions of a so-called stampede. The total gold production of the Innoko and Iditarod districts in 1910 is estimated to have a value of $825,000,

Piaceb Mining In Innoko-Iditabod Region. 239

Geography.

When gold was discovered on Otter Creek in 1908 all of the Innoko basin constituted a subdivision known as the Innoko precinct and was included in the second judicial division of Alaska, whose court offices are at Nome. This precinct, with its recording oflBce at Ophir, was bounded and described as follows:

Beginning at a point on the eastern bank of the Yukon River, about 50 miles above the village of Anvik and opposite the divide between the Innoko and Yukon rivers; thence following the divide northeasterly to the divide between the Innoko and the Nowi rivers; thence in an easterly direction or southeasterly direction following the divide between the Innoko and the Nowi rivers to a point on the divide between the Innoko and Kuskokwim rivers; thence in a southwesterly direction following the divide between the Innoko and Kuskokwim rivers to the western bank of the Yukon River at a point south of Holy Cross, this last-mentioned line being identical with a part of the northern boundary line of the Kuskokwim precinct; thence northerly along the western bank of the Yukon to the place of binning.

An act of Congress taking effect July 1, 1909, resubdivided Alaska into four judicial divisions instead of three and placed the original Innoko precinct in the fourth division under the court at Fairbanks. A new adjustment of several precincts was made necessary by this redivision and to facilitate recording matters the Innoko precinct as formerly defined was divided into two precincts, the recording office at Ophir being retained to accommodate the miners in the eastern headwater portion of the Innoko Valley, and a new precinct named Otter being formed to include the Iditarod placer-gold district or western part of the Innoko basin. The recording office for the Otter precinct is at the town of Iditarod.

The Iditarod gold-placer district is situated along the upper valley of Iditarod River, about 65 miles east of the settlement of Holy Cross or Koserefski, on the lower Yukon. (See map, PI. XI.) Iditarod River is the largest branch of Innoko River, which is the largest eastern tributary of the lower Y'ukon. The Innoko joins the Yukon about 300 miles from Bering Sea. It flows into the Yukon through two or more divergent and crooked channels in which the currents are so sluggish that they are generally called sloughs. The channel most frequently used by the steamboats that ply the Innoko and Iditarod enters the Yukon a few miles below and opposite Holy Cross. This channel may be considered the mouth of the Innoko. The lower 150 miles of the Innoko is commonly but incorrectly called Shageluk Slough, owing to the fact that a side channel of the Yukon flows into the Innoko at that distance above its mouth. This channel, which is about 35 miles long and navigable for steamboats, leaves the main Yukon about 80 or 90 miles above Holy Cross. It delivers a considerable amount of Yukon water to the Innoko and is of considerable consequence in increasing the volume of the lower 150 miles of that river, but the Innoko proper furnishes by far the largest

240 MINERAL EESOL'RCES OF AtSKA, 1910.

amount, although many )>eraons consider the numth of Innoko River to at the confluence of Shaeluk Slough with the Innoko and name the lower 150 miles of the Imioko channel Shageluk Slough also, tliis designation sIiouM be restricted to tlie side channel that carries Vukon water exclusively.

The main Innoko River is about 500 milee long and with ita tributaries drains tiio laiest part of an extensive area that hes between tlie central lower courses of Yukiiu and Kuikokwim rivers. Its principal or northeastern lieadwaters, upon which the Innoko placers aro situated, he between the Kaiyub Mountains on the northwest and the Kuskokwim Mountains on the southeast, these ranges separating its upper "valley from the drainage of Yukon and Kuskokwim rivers, respectively.

The southern (wrtion of the Innoko basin is drained by Idjtarod River and its tribntaries. Tlie chief or eastern headwaters of this stream rise along tho divide of the Kuskokwim Mountains about 75 miles east of iloly Cross and drain an extensive area that lies along the northwestern slopes of these mountains. Iditarod River flows uito Innoko River about 45 miles above Shageluk Slough, or 200 miles from Holy Cross by the regular steamboat route. In direct distance its source is not more than 100 miles south of its mouth, but the total length of the actual course of the Iditarod is prubiiMy 300 miles, as it luis an extremely meinuU'ring chiiunoj, especially tliroughout its lower portion, for both the Innoko and Iditarod meander widely for many miles through sluggish channels across swampy plains that occupy the lower half of the Innoko Valley. During the spring freshets the whole lower valleys of these rivers are inundated, and after the floods have subsided large areas of swamps, shallow ponds, ami lakes remain over its surface.

Iditarod River drains a considerable area on the southeastern side of lower Yukon Valley along its southeBstem boundary, the Kuskokwim Mountains. The 100 miles of its cours*is along the northwestern foolliills of these mountains and the river receives its chief headwater tributaries from them. Broadly considered the Iditarod district comprises an area of about 500 square miles that is drained by several of the larger eastern tributaries of tliis river. In upstream order these tributaries are named Caribou, Otter, and Bonanza creeks. Extensive locations for placer minuig have been made throughout the vaUeys of these streams, but the area within which actual tliscoverios of placer gold have been made and mining operations imdertaken is much smaller and may be included within a tract 10 miles square. Practically all the productive placer ground now known lies within the valley of Otter Creek and about the sources of several small streams just south of Flat Creek, which is the most important gold-bearing tributary of Otter Creek.

Placeb Mining In Innoko-Iditarod Region. 241

TRANSPORTATION, SETTIjEMENTS, AND POPUIiATION.

The only practical way of transporting supplies to this district is by means of shallow-draft stem-wheel river steamboats plying Yukon, Iimoko, and Iditarod rivers. During 1910 most of the freight was brought up the Yukon to Holy Cross on large steamboats and there transferred to smaller ones which ascended the Innoko and Iditarod to the supply points that have been established at several places along its course. Considerable freight, consisting largely of mining machinery, was also brought down the Yukon from Fairbanks and taken to the new district by way of Shageluk Slough and Innoko and Iditarod rivers.

During the stages of high water that ])revail in these rivers in June and sometimes at other periods during the summer months steamboats of moderate size are able to ascend the Iditarod as far as the mouth of Otter Creek, a distance of about 216 miles above its mouth. During the average summer stages of water, however, the moderatesized steamboats can not ascend the Iditarod so far, and the upper settlements can be reached only by much smaller steamboats and launches. This variable condition of the navigability of the river has determined the location of the supply settlements on the Iditarod.

At present there are three such settlements of importance on Iditarod River. These, in down-river order, are named Otter, at the mouth of the stream of that name, which is about 216 miles above the mouth of the river; Iditarod, situated about 16 miles by the course of the river below Otter; and Dikeman, which in air-line distance is only 29 miles but by the river 70 miles below Iditarod. Dikeman is about 130 miles up the Iditarod from its mouth, or 330 miles from Holy Cross by the steamboat route, and the town of Iditarod is about 400 miles from Holy Cross.

Dikeman is situated on the east bank of Iditarod River where it leaves the low foothills that border its upper course. The river from Dikeman to the Innoko flows sluggishly 130 miles by a very tortuous channel across the swampy plains of its lower valley. Its channel is deep enough at all stages of water for moderate -sized Yukon steamboats to ascend to Dikeman, and tliis point is considered the head of low-water navigation. Dikeman has been established as a storage and transfer point for freight and passengers to the placer district, and several of the larger commercial companies have built substantial warehouses and stores here for that purpose. Its population in 1910 numbered about 100 persons.

The town of Iditarod, with a population of 600 or 700 persons, has been, since its establishment in June, 1910, the commercial center of the district. It is situated on the east side of the river, 70 miles above Dikeman by the summer water route, or 31 miles by a wititer sled trail recently laid out by the Alaska Road Commission. The 98319''— BuU. 480—11 16

242 Mineral Kebocbces Of Alaska, 1910.

town aile in on a rattier unfavorable frozen boggy bank, wliose onJy local advantage for the purpose of settlement seems to be that it stands high enough to be above the waters of spring fresliets. A number of substantial warehouses and business buildings have been erected there, and all the activities of a boom town were much in evidence during the summer of 1910.

Tliis town ia 8 to 12 miles from the mmes by an overland route that is too boggy in its present condition to be of much service for Iiauliug supplies to the mining camps with horses and wagons. Although tliis method of transportation was carried on during the summer of IH 10 it was accomplished with great difficulty and expense, and unless a good road w built this overland route can not compete with the water route by way of the river and Otter Creek.

The settlement of Otter, at tlie mouth of Otter Creek, ia an important point for the ilistribution of supplies to the mules, as steamboats can reach this place at times of high water and from it freight can be transported up Otter Creek to the diggings by means of scows towed by horses. The distances from the mouth of Ott<!r Creek to tJie mining settlements on that stream are from 16 to 20 miles by the water route or from 8 to 10 miles by laud,

Tlie most important mining settlement is named Flat. It is located oD the east bank of Otter Creek about 16 miles above it confluence with the Idltarod just below the mouth of Flat Crock, which is the most iiupurtaiit tributary of Otter Creek liriiriri<; pliicer gold. About 2 miles above Flat, on the west side of Otter Creek, ia a place named Bowlder, and from 1 to 2 miles farther up Otter Creek, on the same side of the main stream, is a stragghng settlement called Discoverj- because it is located at the mining claim so designated.

In 1910 the population of Otter numbered about 50, and Flat and Flat Creek probably had a population of 400. Bowlder, Discovery, and the near-by claims along Otter Creek had about 300 residents. During 1910 there was also a floating population of about 1,000 men in the district, who were temporarily campeil at different places along the river and creeks. In August and September about 500 of these men were busy locating placer claims on tributariett of the Kuskokwim opposite those of the Iditarod to the south. It is estimated that on an average 2,.500 people were in the Iditarod region during the summer of IfllO.

Supplies are transported to the Innoko district by taking them up Innoko River on medium-sized Yukon steamboats as far as Dishkakat, which, like Dikeman, on the Iditarod, is considered the head of ordinary low-water navigation for such craft. At times of high water smaller steamboats may ascend tlie Innoko about 100 miles above Dishkakat to the vicinity of the North Fork, some 90 miles below

Placer Mining In Innoko-Iditarod Region. 243

Ophir. From the North Fork the freight is carried to Ophir in lots of 4 to 6 tons on light-draft scows towed by horses.

A considerable amount of supplies for the Innoko placer district is now being brought up Kuskokwim and Takotna rivers to a settlement called Takotna Station, which is about 20 miles from Ophir by a winter sled trail that crosses a low divide between the Innoko and Takotna drainage. The Kuskokwim route appears to be the best way to supply the Innoko placer district.

Geologic Sketch.

The Kuskokwim Mountains form a divide from 2,000 to 4,000 feet above sea level between the drainage of Innoko and Iditarod rivers and that of the central part of the Kuskokwim Valley. The hardrock formations of the region are fairly well exposed along the crest of this range and the secondary ridges which separate the streams that flow therefrom. These mountains appear to be mostly made up of a widespread series of sedimentary formations largely of ilesozoic age, witli which are intimately associated considerable amounts of volcanic rocks of various kinds, some of which, at least, are older than a large part of the sedimentary formations, because fragmental detrital materials derived from the volcanic rocks are commonly interbedded with the sedijnents as tuffs.

Tlie sedimentary rocks of the Kuskokwim Moimtains are a series of alternating beds of sandstones, carbonaceous and calcareous shales, slialy and siliceous limestones, granitic arkoses, volcanic tufts, and conglomerates. The sandstones are generally rather thinly bedded and flaggy. The shales range from soft to fairly hard rocks and in tlie Innoko district appear to be altered to slates. Near their contacts with granitic intnisives they have been locally hardened into blocky quartzites and argiUites.

The general structural trend of the sedimentary series is northeast and southwest, with southeasterly and northwesterly dips at angles varying from 20° to 80°.

The volcanic rocks of these mountains are more or less altered rocks of basaltic types. They all have a general greenish color such as naturally belongs to ancient and somewhat altered lavas that are considerably decomposed. Closely associated with these volcanic rocks in many places occur large amounts of more or less consolidated fragmental igneous material which appears to be directly derived from the volcanic rocks and so may be classed as tuff. These beds of tuffs in places appear to change laterally into shales and sandstones of undoubted sedimentary origin, or to be at least interbedded dth such rocks. The definite relations of the sedimentary formations to one another and to the volcanic rocks have

[ 244 Mikkkal Bksources Of Alaska, I9I0.

not biMin determined, and bo far aa the evidence goes they may he proviBionally considered as essentially contemporaneous in origin, their differences being accounted for by variations in local conditions. It may bo noted, however, that tlie volcanic and intrusive igneous formations appear to be must extensively developed along the main divide of the Kuskoknim Mountains and that the sedimentary' formations of these mountains become more free from mixture with either Tolcanic or intrusive rocks along both their outlying northwestern and southeastern flanks as they recede from the backbone of the range. These probable relations seem to indicate that the volcanic rocks and closely associated tuffs and sediments which lie along the (rentci" of the Kuskokwim Mountains may be older than the outlying Redimontani' formations that make up the mountain flanks, and the presence of arkose sandstones, apparently deriverl from granitic roclts, in these flanking formations seems to indicate that the granjtic masses distributed along the mountains, which may be the source Tfit the nrkose sandstone.'<, are older than at least a part of the outlying formations, Tlie few fragmeiitarv- fossil remains of land plants and marine-shell forms that have so far been found in these aoiliments point to an nniJonhtecl Mesozoic age for the series and a probable Cretaceous age for its younger members, of which the arkose sandstones appear to fonn a part. This meager evidence indicate.'! thfit ii Inrye prt of tlic gnmitic intrusive rocks arc of early or p re-Cretaceous age; at any rate the older sedimentary and closely associated volcanic formations ap])ear to have been the country rock which the intrusives penetrated.

Most of the highest areas throughout this general region are made up laiely of mountainous masses of these intrusive granitic rocks. Dikelike bodies of these siliceous intrusives trend in different directions, but mostly northeastward and southwest ward, across the intervening areas of sedimentary rocks in a manner that vaguely suggests that there may be a more or less connected network of intrusive dikelike bodies extending between the large intrusive centers. The dikes are ordinarily of siliceous varieties, such as biotite granites and hornblende diorites, sometimes porphyritic, although some are more basic, such as diaba.se porphyn,' and basalt. It is possible that these more basic dikes may belong to an earlier period of intrusion and be more closely connected with the volcanic flow rocks.

The sedimentary' rocks are generally more or less metamorphosed near the intrusives, the degree of alteration becoming progressively less with distance from the contacts. The contact metamorphism that has occiirred along these intrusives apjicurs fo have caused the conditions that have brought about, in places at least, the mineralization along the contact zones from which the placer gold has been derived.

Placee Mining In Innoko-Iditarod Region. 245

The rocks of the Kuskokwim Mountains do not, in general, contain well-marked veins, but in the vicinity of some of the siliceous dikes the country rocks are altered, chiefly by silicification, at some places for only a few feet from the contact but at others for considerable distances, and there occur narrow vein deposits near the contacts of dikes with stratified rocks, and locally small gash veins within the dikes themselves. The material of these veins is generally quartz but in places calcite. The metallic minerals associated with these veinlets and zones of alteration are sulphides, of which iron pyrite, chalcopyrite, galena, and cinnabar are the most common kinds. Some of these minerals are presumed to be gold bearing because the placer gold is evidently derived from the decomposition and erosion of these mineralized contact zones.

Occurrence And Distribution Of The Placer

Gold.

Obigin Of The Placebs.

The placer-gold deposits of the Iditarod district appear to be of distinctly local origin. As now developed, the commercially important stream concentrations of gold are small in extent and their distribution is evidently very closely dependent upon the apparent bedrock origin of the gold. The origin of the placer gold appears to be closely connected with the mineralization that has taken place locally along the contacts of siliceous intrusive rocks with the more basic igneous rocks and the sedimentary formations. For example, in the valley of Otter Creek the placer gold is foimd in very close association with bodies of granitic intrusive rock. Here two bodies of granite seem to be present, one lying across the valley of Otter Creek just below Granite Gulch and the other on the head of Flat Creek, a tributary on the south side of Otter Creek. These granitic masses have a width of at least half a mile and a length of 1 to 3 miles. Their longest dimensions have a northeasterly and southwesterly direction in conformity with the general structural trend of the sedimentary formations; they are in line with each other along this trend and may be connected, although this is not known to be the case.

In the Innoko district the direct local derivation of the placer gold from zones of contact mineraUzation is not so evident as it is in the Iditarod. There are no large intrusive bodies very near the Innoko placers, and the gold seems to be distributed farther from an apparent bedrock source. There are, however, some siliceous dikes cutting the country rocks within the valleys of the placer streams. Some of these dikes are known to be mineralized with pyrite, and it may be presumed there are more of them so mineralized. Vein quartz occurs along the walls of some of the dikes, and some of Uv\& %.xVl

MINEEAl. BESOUKfCS OF ALASKA, lOW.

tia known to contain gold. Thus it appears fliat the jiluccr gold is Istively local in origin distribution.

DfNOKO OOLD-PLCER DISTRICT.

An account of tlu- Jnnoko district lias alrp.idy been piiblislied ' in whicli a gonornl description of this region has been given and its mining development up to 190S outlined. Therefore only a brief review and summary of the progress of miiimg development up to 1910 i.'i given here.

Practically all the mining in this diatrict has Iwen performct! within the valleys of Opiiir, Spruce, Little, Ganes, and Yankee creeks. The placer gold ocean* in creek, bench, and gulch deposits. Various methods df mining have been practiced according to the position and character of tlie deposits; sinking and drifting, groundsluicing ami open cut, scraping and hoisting by steam power, shoveling and hoisluig by fiand, and canvas-hose liydrau licking have all been used in different combinations npon the different creeks.

Oanrk Cheek.

Placer gold was first minml in thf Innoko district on Gunes Creek in ID07, near the plac* wliere it was discovered the previous summer. It soon became apparent to those interested in Hainis on this stream that the gold-bearing deposits which could be mined most profitably were not those in the present stream bed, but older gravels which rest on bedrock benches that now stand from 30 to 60 feet above the level of Ganes Creek. These benches, wliich are remnants of an older valley floor, are situated for the most part on the east side of the creek about 7 miles above its mouth. Tlicy are from 100 to 500 or 600 feet wide and extend along the valley for several miles, with interruptions at intervals caused by gulches that have been cut down them liy nine short tributary stretims. These bench gravels have been mined each summer since 1007 at the most favorable places by half a dozen or more parties, each composetl of about three to six men. The mining operations have not been conducted upon an exiensive scale because enough water can not Iks obtained from the short gulch streams that rise along the eastern side of the valley behind and above the benches for elfeclive hytlrauhcldng with a large plant, and because the capital with which to purcliase and install the equipment of such a plant has been beyond the moderate resources of the men who are interested in the ground. The result is that all the mining has been conducted uijon selected areas of small extent in as simple and inexpensive a manner as possible. A cover of muck and silt is sluiced oJT with sln'ams of water led upon

lUuU. U. S. QooJ. Survp>' No. 110, lUlD.

Placee Mining In Innoko-Iditarod Region. 247

the benches from small ditches that have been dug up the short gulch tributaries. The supply of water obtainable from these gulches varies much from year to year and even from week to week during the same summer; consequently the amount of mining that may be accomplished during a given season is always uncertain. On some of the bench claims enough water for the mines can be obtained only during the spring thaw and after uncertain rains. During dry summers all mining operations on the Ganes benches are greatly handicapped by arcity of water.

After the overburden, which varies from 2 to 12 feet in thickness, has been removed the pay gravels, which are from 1 to 6 feet thick, are shoveled into lines of sluice boxes arranged to carry the tailings over the edge of the bench or dump them into gulches cut below the level of the bench — wluchever is the more convenient. From 6 inches to 3 feet of splintered and flaky slatelike bedrock which contains gold is also shoveled into the sluice boxes. Considerable areas of these bench deposits that may be worked by these methods still remain, but a large part of the most favorable ground has been mined.

Several drift-mining operations of sUght extent have been conducted along the base of the rock bluffs upon which the gold-bearing gravels rest, and from this source some gold has been obtained. There seems to be no doubt that the gold found in the lower-level gravels along the base of the bluffs that form the benches and in the present bed of Ganes Valley has been derived from the deposits on top of the benches.

The total gold production of the Ganes Creek placers up to the present time is estimated to be about $150,000.

Little Greek.

Little Creek lies northwest of and parallel to the lower part of Ganes Creek, which it joins about half a mile above the Innoko. It is approximately 7 miles long and is separated from Ganes Creek by a ridge about 2 miles wide and 600 feet high.

Gold was discovered on this stream during the summer of 1907 and mining has been conducted since 1908 on claims that occupy the middle 3 miles of its valley bottom. The unconsolidated deposits vary from 10 to 25 feet in depth. In some places they are frozen and in others thawed. They consist largely of mucks and silts, with a small quantity of gravel. In some locahties gravel beds 2 to 4 feet tliick rest on the bedrock beneath the silts, but in many places the silts lie directly on the bedrock and gravels are practically absent. The bedrock of Little Creek is a hardened shale or argiUite that varies in texture from gritty to fine grained. In places it has slaty cleavage, but most of it is massive. Its upper 10 feet is generally very much shattered. It breaks into blocky slabs and shingle fragments

r

848 Minerai, Rrsource.S Of Aiska, 1910.

also iuto i-ouglily columuar 4-sided to 7-aided forms from 2 to 4 inclies ill diameter and from 10 to 18 indite in length. Many of tJipse columnar pieces stand on end in tlio weatliered bedrock, and wliere gold is present iJie best concentrations are generally found in tliis kind of bedrock, which acts as natural riffle blocks. From 2 to 10 feet of the upper part of tlie bedrock is generally thorougiilj" shattered in tliis blocky or slabby manner and the fragments are commonly Bepunited, the spaces between them varying from one-tenth to 1 inch or more in widtli. These spaces are fJled to a depth of 2 fi feet with sediment or silt, which appears to have filtered down from above. Most of the placer gold, wliich consists of flaky, fresh rough pie<:es of small size, occurs in llieae sediment-filled spaces in the bedrock, where it appears to have heeome <concentrated along with the sediments that fill the interspaces. From 2 to 6 foet of the shattered bedrock is dug up in mining, and most of the gold output is obtaincil Iherelrom.

The Little Creek platers have been mined both by surface opencut ground sluicing and underground ainldug and drifting methods, the practice adopted depending upon the position, depth, and condition of the deposits. Along the Talley bottom, where the deposits are deepest and contain more or less perpetual frost, consideralile sinking and drifting work has been done; but this has proved profitable only where the gold happens lo ho concentrnled in quantities above the average. Such concentrations appear to be distributed in disconnected strips and spots along the bedrock floor of the valley, but they are of uncertain extent and dillicuU to trace. As soon as drifts are extended beyond the limits of the richer concentrations or into thawed deposits, the underground work generally becomes improfitable. Though it may be continued for some distance in the hope of finding other rich places, such work is more of the uncertain nature of prospecting than the mining of ground known to contain fairly uniform paying values, such as are essential to success, especially in a district like the lunoko, where all mining operations are expensive.

Underground mining would probably not be undertaken at all in the Innoko district if it were not for the lack of water in sufficient quantity for hydraulic mining and of suHicient grade to the valleys to afTortI dumping space for tailings. None of the workings on Little Creek is more than 30 feet deep, and if enough water could he readily obtained in this valley no doubt all its gold-bearing deposits might be cheaply mined by hydraulic methods if the tailings were elevated. But this stream is so small that the average supply of water is barely sufhcicnt for ordinary sluicing operations, especially during summers of little rainfall. By taking advantage of the more abundant flow of water during the spring thaw and at uncertain times of heavy rainfall, surface open-cut mining has been carried on to a moderate extent at several places, both in the present creek channel and UDon

Piacer Mining In Innoko-Iditarod Region. 249

either side of the stream. The deposits along either side of the present stream are termed "benches'' by the miners; but they are not distinct terraces, such as occur along Ganes Creek, for on Little Creek there is no abrupt break in the vertical position of the gold-bearing deposits as there is on Ganes Creek. They rest on a fairly even bedrock surface that slopes up sufficiently from the lowest part of the valley to afford dumping space for the waste material it is necessary to remove in order to lay bare the gold-bearing bedrock that occurs on either side of the stream at some places. Practically all of the waste overburden consists of silts, clays, and vegetable muck, which varies from 3 to 10 feet in thickness. There is little or no gravel present and cobbles or bowlders are not plentiful.

The waste overburden is removed in the usual manner by groundsluicing or washing it away with streams of water led upon it from small ditches that have been dug along the valley slopes above. After the bedrock in these open cuts has been laid bare, from 2 to 4 feet of the upper shattered part is loosened with picks and washed through lines of sluice boxes to recover the gold that is lodged in the sediment that fills its crevices.

An average of six to eight outfits have mined along Little Creek since 1908. The open-cut work can be done only during the season of flowing water and then only at the times of maximum flow, which are generally in the early part of the summer. The drift mining may be carried on more or less throughout the year.

Some of the open-cut mining has produced as much as $1 to the square foot of bedrock surface, but most of it yields less than tliis. In the underground drifts, as in the open cuts, about 4 feet of shattered bedrock is dug up and washed for gold, and good ground will yield $1.50 to the cubic yard, but the additional cost of steam thawing, of the labor to hoist the loaded buckets from the shaft by hand windlasses, and of the unproductive work performed in extending the drifts through ground that contains little or no gold reduces the* profits of work of this kind. The total production of gold from Little Creek since 1908 probably amounts to about $150,000.

Spruce Creek.

Spruce Creek is northwest of and parallel to Little Creek, being separated from it by a ridge about 2 miles wide and some 800 or 900 feet high. Its valley is about 6 miles long and is similar to that of Little Creek. The country rock within it is likewise the same hard blocky shale or argillite. The creek appears to carry a Uttl 5 more water than Little Creek but still not enough to permit very satisfactory hydraulic operations.

The alluvial lands along this valley have been located for placer mining since 1908, and although some prospecting has been done at several places along the stream from time to tiixxi iio\)cica\%

I 260 MtNERAL RESOURCES OF ALASKA, 1010.

K discovered that to productiv* mining within its basin until (he

B- autumn of 1909, when prospects were found on a low boncli

V aituiiteij about 3 miles iip the valley on its eastern side, about

H2OO j-ards from the present course of the stretim. At this locality

B the creek now flows along the base of a steep bedrock slope that

K forms the western Hiile of (lie Tulley, nnd the gold-bearing area

extends eastward from it, the bedrock floor of the Talley rising some

30 or 40 feet in this direction within a distance of about 500

feet. This sloping valley floor is covered by 5 to 15 feet of clay,

silt, and muck, the greater part of which is frozen. The eastern

riso of both the bedrock across the valley and the surface of its

overburden make it practicable to groundsluice the waste mantle

aside into the creek in the same manner as on Little Creek.

B As the supply of water obtainable from Spruce Creek is somewhat

H'lQoro abundiLDt than that of Little Creek, the groundsluicing open-

L'CUt work may be carried oQ more continuously throughout the sum-

mer. The claims that are being mined receive water from above,

Hibrought by a ditch about 9,000 fet long that has beeji dug along

libo eastern side of the valley, so as to deliver water about 50 feet

H-ftbovo the creek at its lowei' end, where it is upon the sloping

H bench thi-ough canvas hose and the gold-bearing bedrock is cleared

H of ids frozen mantle of clay and muck. The shattered bedrock, in

which th,- goi.l or-curs in the ftainc as tm Little Creek, is

then loosened with picks and shoveled into lines of sluice boxes

for washing.

About J20,000 worth of gold was mined from these so-called bench claims during the summer of 1910 by the open-cut groundsluicing method described above.

No productive drift mining has yet been done in this valley.

Ophik Creek.

Ophir Creek lies about 1 J miles northwest of and parallel to Spruce Creek. It is about the same length (6 or 7 miles) and size as Spruce Creek, and the ridge dividing them is about the same height as that between Spruce and Little creeks. In brief, all three of these valley have very similar features of length, width, depth, direction, bedrock, and other general characteristics.

Ophir Creek differs from Spruce and Little creeks principally in that its placer gold is more abundantly and uniform!}- distributed along the bottom of its bedrock channel and that the valley is more evenly filled across and along its bottom with silts, clays, and muck, which for the most part are frozen and of uniform thickness. The valley filling averages 25 to 30 feet in de])th. At some localities it is a few feet less than 25 feet and only in a few places more than 30 feet from the surface to bedrock. As a rule there is little gravel in the stream deposits, but occasionally some gravel is found on bedrock.

MaOeH Mining in iNNOKd-iDitAROf) region. 251

Most of the placer gold, as on Little and Spruce creeks, is lodged in the sediment that fills the numerous crevices in the shattered bedrock to a depth of 2 to 5 feet. The best concentration of gold, or the pay streak, varies from 20 to 70 feet in width across the rock floor, the wider distribution of gold appearing to be along the lower part of the valley. The pay streak is not always continuous or of uniform richness along the length of the valley. At some places the gold is concentrated more abundantly on one or the otlier side of the bedrock channel near what are called 'rims, which are generally upraised portions of harder bedrock; at other places it is found somewhat restricted to small areas or patches of bedrock ; but on some claims the gold is rather uniformly distributed in the sliattered bedrock over considerable areas.

Although the placer-gold deposits in Ophir Valley are nowhere more than 35 feet below the surface and may be classed as comparatively shallow diggings, practically all the mining that has been performed along the creek has been done by sinking and drifting with the aid of steam thawing. Mining of this kind has been carried on continuously along Ophir Creek since 1908, in the spring of wliich year gold in paying quantities was first discovered in this valley. Most of the mining has been accomplished with very crude and inadequate equipment, various kinds of small boilers of the prospecting tjTe being commonly used to generate the steam for thawing the frozen ground. Many of these boilers are of insufficient capacity for effective work. Most of the hoisting from the shafts has been done with homemade wooden hand windlasses operated by one or two men, but recently several operators have installed automatic-dumping steam-hoist equipment.

The largest part of the gold-bearing material is mined during the winter and ac9umulated on dump piles which are washed for their gold content at the time of the spring thaw, when water is more plentiful than at any other time of the year. The supply of water available for sluicing during ordinary summer seasons is never abundant and during dry periods is often entirely insufficient. At some places sluicing can be carried on during the summer season only after heavy rains and, as such times of increased water suppi} can not be predicted or depended upon, the amount of gold washing that may be accomplished during a summer is uncertain. Occasionally portions of a summers output of gold-bearing material can not be washed until the spring after it is mined.

It is no doubt a fortunate circumstance that mining operations on Ophir Creek have not been handicapped by having the placer claims located in the objectionable form of large association groups, whereby the mining privileges to large tracts of land may be dominated by a few individuals, who generally have not the resources or initiative to mine the ground themselves and generally retard mimn

SS2 MTNEBAI RESOrnOES OF ALASKA, lOlO. H

by making unreasonable or even proliibitivp demands of those who may wisli to mine. All the properties on Ophir Creek are located in tlie form of single claims of about 20 acres or leas, so the interests in mining; ground are sufliriently divided to afford ojtportiinities for independent mining to a number of individuals. There are two discovery claims on tliis creek, a lower and an upper. Eight claims are numbered ia dowTistream order below Jjower Discovery claun, and above thi? claim they ore numbered upstream to "No, 12 above Iower Discovery." "No. 12 above" is the samp us Upper Discoverj', and U|>streani from this claim the numbers begin again with 1 and extend to the head of the valley.

Productive mining has been done along Ophir Creek the summer of 190X, on nearly all the claims from "No. 4 below Iower Discovery" to '"No, 4 above Upper Discovery," which cover 4 or 5 miles of the middle length of the creek. From 15 to 20 partie.s have been mining aloag the valley each year. These parties number from three to ten men each. The larger operators have frequently employed labor, but much of Uie mining has been done by tliree or four men working together on a. partnership basis,

Ophir Creek has been the largest and steadiest producer in the Innoko district, Tlie output of placer gold from it for the tliMft years 1908 to 1910 t.tals about

Yankee Creek,

Yankee Creek is a stream of considerable size and about 12 miles long that lies about 4 miles southeast of the lower course of Ganes Creek. Its valley trends in the same direction as that of Ganes Creek and the other three tributaries of the upper Innoko, upon which placer mining is being conducted. All five these streams flow from the southwest toward the northeast. The general jtarallelism of these valleys and the ridges which divide them may be due to structural features of the sedimentary formations of the district, for these appear to extend in a general northeast-southwest direction throughout the region.

Although locations were made on Yankee Creek for ])lacer mining in 1907, gold in paying quantities was not found in its valley until 1909. Most of the mining has been done upon ]>artM of two large tracts located in the form of association-group claims, about 160 acres each, situated 6 or 7 miles above the mout h of the creek. The titles to someof this ground became a matter of litigation in court as soon as the land was learned to be of value, the questions involved being whether the first locators, who were not present when gold in ]>aging quantities was found, had not forfeited their rights in the property by abandonment, whether they really knew there was gold on the claims when they located them, and whether they did any assessment work to show their intentions to mine the ground after they made their origiual

Placeb Mining In Innoko-Iditabod Region. 253

locations. The point worthy of notice is that the ground in dispute was located in the form of large association-group claims, so that the htigation involved a large area of land and thus retarded mining developments in a way that would not have occurred if the ground had been located in the form of single 20-acre claims by individuals.

The gold-bearing deposits that are being mined on Yankee Creek differ somewhat from those on Little, Spruce, and Ophir creeks in that they are more shallow, being only about 8 feet deep, and are composed largely of beds of coarse gravel from 5 to 7 feet thick, covered by only 1 to 3 feet of silt and muck. The valley bottom has a fairly broad, flat cross section and its sides have moderate slopes in most places, so the unconsoUdated deposits have a uniform depth and considerable width. Tlie stream has a good flow of water and more of a grade than the other placer creeks. The gravel deposits appear to be well drained and largely unfrozen, perhaps because the unconsoUdated deposits are not deep, because there is a good circulation of water through the coarse porous gravel, and also because the silt and muck covering the gravels is comparatively thin.

The mining of these shallow placer deposits is summer open-cut work. After the deposits covering the surface are groundsluiced off for a width of about 100 feet the gravels are shoveled into wheelbarrows and then conveyed to a hoist bucket suspended from an oVerhead cable and elevated to a dump or rock box at the upper end of a Une of sluice boxes erected on trestles. The coarser material is forked out of the rock box and the remainder washed through the rifle boxes. The general procedure is the same as that practiced on Flat Creek, in the Iditarod district (see pp. 255-258), but the operations have not been as extensive as those on Flat Creek, partly because some of the ground on Yankee Creek has been tied up by litigation, and also because there has not been an adequate supply of steam hoisting and scraping machinery available in the Innoko district. Only one steam hoisting plant was installed on Yankee Creek in 1910. The other operators were hoisting the gold-bearing gravel to the sluice boxes by hand windlasses.

Yankee Creek first became a producer in 1909, the for that year amounting to about $15,000. During 1910 from $50,000 to $60,000 was mined. The total production for 1909-10 amounts to about $75,000.

Xditabod Gold-Placeb District. Otter Creek.

Otter Creek is in reaUty a small river whose valley has a length of about 30 miles and a width between the crests of its bounding divides of 6 to 8 miles. For the greater part of its length Otter Creek flows near the right-hand aide of its valley bottom along the foot of abrupt

254 Mineba.L Besources Op Ajska, I!)10.

eiopos thiit rise directly from llio slreara chiinncl to heights of 500 to 1 ,600 feet witliiii dtstanres of ! to "J miles. At the scene of mining on Ottir Creek the floor of the valley is about on<*-fourth mile wiih' ami the placer claims practically all lie on the left aide of the stream. Beyond these claims the left slopes of the valley rise gradually to the dh-ide, 4 or 5 miles distant. Tlie volume of water in Otter Creel* is large enough to afford trausportfttion for supplies by means of horse 8C0W8 and poling boats from Iditarod River to the mines, but the grade of the vulley is not sufficient to make tlita water available for hyilriiulicking the placer deposits.

Tlie productive gotd-placer ground lying along Otter Creek is of local extent when the length and size of the valley are considered. The present raining operations on tliis creek are confined to a limited tract of land nbout 2 miles long and one-fourth mile wide situated in the valley bottom about 12 miles above its mouth. iJegiuning at the upper limit of known productive ground, tho mining claims included wilhiii this tract in downstream order are as follows:

The Gum Boot group, whirli consists of about 00 acres that extends across Otter Creek at the mouth of a right-hand tributary nameil Granif* Creek, lies between claims located on the lower part of Granite CYeek and the Otter Association group. The latter group, which is 1 mile Iddj; and onr-finirth niiln wide, oxtcmls nkin<: the center of Otter Valley Flat, with (he mouth of Granite Creek about opposite the middle of its lengtli. These two association groups have been prospected and the conclusion reached that gold in paying <|unntitics lUwa not occur in them aliove Granite Gulch.

Below Otter Association group there is a row of six single placer claims designated Nos. 2 and 1 above Discoverv', Discovery claim, and Nos. 1 , 2, and below Discover)-. Along the left side of these six clainLS is another Vmc of simihir claims with corresponding numbers and the additional dcsigniition "first tier of left-limit bench claims." There i.-f also ])art of a second tier of left-limit liench claims and several small fractional claims. Altogether these claims cover the width of the valley flat for about 1 i miles along its length. Below No. 3 below Discover!' there is a group of claims named the K. P. M. Association.

It is reported that prospects of gold are found as far down Otter Crook as the K. P. M. Association, but it is generally conceded by those who have prospected along Otter \'alley that gold in productive quantities, in the sense that is now accejited in the district, does not occur below the vicinity of claim No. 2 below Discovery. Thus the general extent of tlie productive area on Otter Creek, as now defined, is that part of its valley floor that extends ilownsfrenm from the mouth of Granite Creek for about H miles. Throughout this area the country rock upon which the gold-bearing deposits rest is com-

Placeb Mining In Innoko-Iditarod Region. 255

posed largely of granitic rocks, the upper parts of which are considerably decomposed and overlain by a layer of residual sands derived from the granites. Itese sands grade into the solid countryrock in many places and as a whole do not appear to be very much washed or sorted by running water. Mixed with them are some gravels and a considerable number of residual granite blocks, bowlders, and cobbles, which are evidently harder portions of the granite that have resisted decay and have not been moved any great distance from their original bedrock source. These deposits hold the placer gold, which also has the same residual character as the material in which it rests in that it consists mostly of sharp, rough, flaky pieces, rather than of smooth waterworn nuggets. Most of the gold occurs in the sands and decayed bedrock. Much of it has sifted down into crevices in the bedrock, where it is present in thin seams of fine sediment that fill these cracks to a depth of 3 to 6 feet. The gold also has a tendency to concentrate more abundantly upon layers of clayey sediment interbedded with the sands and gravels.

The gold-bearing placer beds vary in thickness from 1 to 6 feet. In mining them from 2 to 6 feet of the bedrock upon which the unconsolidated deposits rest is also taken up to recover the gold in its crevices. Covering these deposits is an overburden of sediment and vegetable muck from 4 to 12 feet thick. Altogether the unconsolidated materials of the placer area on Otter Creek have a total thickness of 10 to 20 feet and the placers are classed as shallow. They are in general frozen, but where mining is being done it has been found that the deposits are not frozen throughout and that considerable areas are thawed and wet. This may be caused by the presence in the valley of large quantities of flowing water. Where the gravels are thawed underground water is abundant, but as all the productive mining is done by open-cut methods the presence of flowing water and thawed ground does not hinder working them as it does in deep or underground mining.

Flat Creek.

Flat Creek is a southeni tributary to Otter Creek, which it joins about 2i miles below Discovery. It has its source on a wide-topped mountain mass at an elevation of about 1,600 feet above sea level and flows about true north for 5 miles. The elevation of Otter Creek at the mouth of Flat Creek is about 300 feet above sea level, but although there is a difference of about 1,300 feet between the mouth and source of Flat Creek about 1,000 feet of this difference occurs within 1 nyle of its head, and the lower 4 mUes of its valley has a comparatively low% even grade of about 100 feet to the mile. It is this characteristic of the valley that has suggested the name Flat. This name is also applied to the most important mining settlement

256 Mineral Resources Of Alaska, 1D10.

in llip district, which is located on the south bank of Otter at the mouth of Flat Creek.

The liead of Flat Creek valley is a semicircular, steep-sided hasin whose catchment area is laie in proportion to the size of the valley w a whole, and for this reason Flat Creek has a larger volume of water than is usual for so short a stream.

The of intrusive granite previously mentioned (p. 24.5) as extending across the head of Flat Creek occupies practically all of the steep headwater slopes of this vaJley, or the upper mile of its length, hut throughout the rest of the valley, or its lower 4 miles, Uie softer sedimentary formations of the region occur. Along tlie Bonc of contact of the granitic and sedimentar>' rocks considerable alteration has taken place, and mineralization appeiirs to have occurred in hoth along a belt of considerable width. Quartz strikers from 6 tq 12 inches tliick occur in the granites, and the sandstones and shales have been hardened to quartzits and argillites or blocky slatos. Tlie hardening of tlie sedimentary rocks extends as far as a mile from the granite but gradually becomes less with iucreasiog distance from the

k contact. Tiiis contact crosses the upper part of tlie valley in a diagonal northeast-southwest direction along the lower slopes of its Iiead- Water basin, then passes up through a saddle on the divide to the southwest and continues across Happy Gulch, a headwater of Willow Creek, 11 short (ributar>- oF Iditarod River west of Flat Creek. The southwestern end of the Flat Creek granite mass is a short distance southwest of Happy Gulch. Placer gold is found on Happy Gulch and Willow Creek.

The richest gold-placer deposits so far found in the Iditarod district occur on Flat Creek from 3 to 4 miles above its mouth. The bedrock origin of this gold is apparently the zone of alteration and mineralization along the contact of the granites with the sedimentary formations that cross the upper ]>art of the valley. The placer mining claims that include the productive ground are of such iirular sizes and shapes that a general written description, unaccompanied by a detailed plat, can not give an ' intelligible idea of their location or extent with reference to one another, so individual properties will not be mentioneil in this a<:count. The side and headwater slopes of the valley are also covered by clauns of various extent and area. About the head of the valley most of the claims are in the form of association groups that contain the equivalents of two to eight single 20-acre placer claims.

In general the prospected ground covers all of the valley Soor of Flat Creek from mouth to source, but at present the ipoBt active mining development is on the upper part of Flat Creek, from 3 to 4 miles above its mouth. The gold-bearing deposits on this part of the creek are from 10 to 25 feet deep. They are composed largely

Placeb Mining In Innoko-Iditarod Begion. 257

of gravels, sands, silts, and a considerable number of bowlders, mostly derived from the decomposition and erosion of the granite country rock that forms practically all the headwater slopes of the valley throughout the upper mile of its length. This granite is deeply decayed and its surface is thickly covered with large blocks and bowlders of the same rock, which are mostly residual accumulations of its more resistant portions. Some of these bowlders and slabs are fully 20 feet and a large number are more than 3 feet in their greater dimensions. To travel over these slopes often necessitates stepping from one bowlder to another, as there are many open spaces between them, although for the most part they lie as a closely packed mantle of d6bris from 5 to 20 feet thick with smaller fragments and cobbles wedged between them, and the slopes are partly covered by sandy soil and turf, on which grow some good spruce timber and dense thickets of alder and willow brush. A large part of the precipitation that falls about the head of the valley sinks beneath this mantle of loose rock and flows down by many undergroimd channels between and under the bowlders, to reappear near the foot of the slopes and form Flat Creek.

Placer gold has been foimd in paying quantities along the lower slopes of the granite area, where the bedrock is decayed granite and the wash is of granite bowlders, cobbles, and gravels. This gold is, with Uttle doubt, derived from the mineraUzed quartz veinlets that occur in the granite and where now found is concentrated from the residual granite sands by the numerous small streams that flow down the slopes. The gold is in rough, flaky pieces, some of them attached to angular fragments of quartz that appear as if they may be freshly separated from vein matter.

The richest concentrations of placer gold, however, are downstream from the granite contact, where they rest upon and within the hard, blocky fractured sedimentary bedrock as successive outwash accumulations derived from the numerous small streams of the granite headwater slopes. The sands, gravels, bowlders, and gold have been fed into the upper part of Flat Valley by these small streams and spread out below along its course by the larger combined flow of water. The unconsoUdated deposits along the lower 4 miles of Flat Creek become progressively finer in texture downstream. Along the upper part of the valley bottom bowlders, coarse gravels, and sands occur in larger proportion than fine sediments, while in the lower parts of the valley the finer sands, silts, clay, and vegetable muck become greater in amount.

The distribution of the placer gold in the unconsoUdated deposits along Flat Creek has apparently occurred in the same order as the deposition of the coarser and finer sediments. The gold appears to be d8319**~BuU. 480—11 17

258 MINERAL, BESOUltCES OF Al,ASKA, 1910.

maul nbtindantly concentrated along the upper part of the valley imii to become less in quantity and finer in size itnwnatream from it source, the richest placers being located from 3 to 4 miles above the mouth of the creek. This is apparently due to Uie probable bedrock origin of the gold at or near the contact of the intrusive mass with the sedimentary rocks that cross the head of the valley anil also to the fact that the headwater fitreams flowing over the mineralized granites have gathered and dumped gold-bearing wasli info the upper part of the main valley, where the combineil drainage loses much of its grade and transporting capacity a short distance below Uie mineralized contact belt. In consequence of tliis tlie ability of the runnijig water to concentrate tlie gold in the gravels and sands is greater on the upper section of the stream than elsewhere.

On the upper part of Flat Creek the coarse unconsolidated deposits are not overlain by a very thick barren cover of frozen sediment. The transporting power of tlie creek appears to be sufHcicnt to carry most of the fine sediment farther downstream, for such deposits of silt with vegetable muck become thicker and more widespread toward the mouth of tlie valley.

The best pay layers in the washed deposits are the lowermost beib of gravels and sands from 1 to 3 feet thick that rest upon the bedrock surface and underlie from 16 to 20 feet of less productive or locally barren iiiatcriiil, Ilowt'ver, at some jihiccs tlie iijjpcr part of the creek nearly the whole thickness of washed material contains more or less gold, fine light particles of it being found in the soil just beneath thp turf. Much of the placer gold is also found from 3 to 6 feet down in the fracture cracks of the hardened sedimentary bedrock, where flaky pieces are embedded in thin seams of fine sediment that have been deposited therein. Without doubt this gold has been sifted down from the overlying sands and gravels by circulating water that has filtered through them into the crevices in the bedrock, the water washing the finer sediment and particles of gold from the sands into the bedrock crevices, where the sediment clogged the spaces and held the gold and the water passed away beneath.

Willow Creek.

WiUow Creek is a stream of about the same length and size as Flat Creek and has its source immediately southwest of the head of Flat Creek over a divide about 1,000 feet high. It flows into Iditarod River about 7 miles above Otter Creek. The principal headwater tributary of Willow Creek is named Happy Gulch.

Happy Gulch has its source on the west side of the same broad, gentle slope of the mountain mass on which rise the southern headwaters of Flat Creek, and like them it drains part of the same granite area. The southwest end of this granite mass is only a short distance southwest of the head of Happy Gulch. Along its northwest

Plageb Mining In Innoko-Iditabod Region. 259

the granite is in contact with the same sedimentary formations that occur on lower Flat Creek and these sedimentary rocks likewise form the country rock throughout the lower valley of Willow Creek. The contact between the granite and sedimentary rocks crosses Happy Gulch near its head. In fact, the gulch topography of this tributary begins near this contact and extends downstream as if it may be due to the fact that the sedimentary rocks in which it is cut are more easily cut down by stream erosion than granite. Although the sedimentary formations are softer than the granite, they nevertheless have been hardened to a considerable degree along their contact with the granite. This alteration is the same as that on Flat Creek. The metamorphism gradually diminishes away from the contact and at a distance of a mile the sandstones and shales are of ordinary hardness and texture.

Mineralization appears to have occurred at and near the contact. The granites are deeply decayed, and accumulations of partly residual and partly waterworn granite sands, gravels, cobbles, and bowlders, similar to those on the slopes of upper Flat Creek valley, occur throughout the upper mile of Happy Gulch. Placer gold of the same rough, angular, little-worn appearance as that found on upper Flat Creek, many pieces showing faces of crystalline form, occurs in the granite wash deposits along Happy Gulch where it cuts across the contact belt. The best concentration of gold appears to be in more or less disconnected layers of gravels and sands from 6 inches to 2 feet thick, mixed with bowlders that lie near the bottom of the unconsolidated deposits. These deposits vary from 5 to 10 feet in thickness. Their surface is covered by a growth of moss and turf and dense thickets of willow and alder brush.

A small amount of open-cut, ground-sluice, pick and shovel mining was performed on Happy Gulch during August and September, 1910, on what is named the Summit claim, which Ls near the head of the gulch and a short distance above the contact of the granite with the sedimentary rocks. This claim is about as far up the gulch as water in sufficient quantity for groundsluicing may be obtained. Even here the adequacy of the supply is largely dependent upon the occurrence of frequent rains on the mountain slopes above. Fortunately these slopes are extensive and of gentle grade, so the run-off is somewhat regular, and by digging small reservoirs enough water may be retained for small mining operations. The granite bedrock on the Summit claim is so deeply decayed that the action of running water quickly erodes down into it, and a ground sluice, if it is allowed to work in one channel too long, readily cuts below the gold-bearmg waterworn material that rests on top of the decomposed bedrock.

Placer gold also occurs along the main valley of Willow Creek for several miles below Happy Gulch. The country rocks of this valley are shales and sandstones which are for the most paTV>

iB60 MINERAL, BESOURCES OF AIISKA, lUlO.

unaltered cuiulitioii ; but witliiri a which extends out dtwut a mile from tli gianitir intrusive mass that crosses tlie upper part of Hiippy (iiilch tliese sotUmcntary rocks have been altered and hardened by tlie deposition witJitn them of considerable ijuartz in the form of numerous thin veinlets. This silicified condition of the sedinjentaij' .rocks appears to be more evident near the contact of Uie griuiitic intrusive mass and to become less marked away from it.

The priiaeiit Willow Creek flows along tlie nortJi wr right-hand eddo of ita valley, in a manner similar to Otter (.'reck, and cuts into ft bingo of bills to form a line of low rock bhifi's. Thus the widtli of its valley floor, wliich is about half mile, lies south of the stream, along its left side. Tlie surface of tJie valley bottom rises gradually to the slopes of tlie bodi-ock ridge that bounds the valley on tlie south. Tins ridge separates Willow Creek from a southern tributary named Gold Creek, which joins Willow Creek about 1 1 miles below the mouth of Happy Gulch. Tliis ridge betwei"!! Willow and Gold creeks is composed of sedimentary' rocks, and it lies vitbin the zone that has been altered by the quartz mineralization wliich has apjiarently been induced by the intrusive granitic rocks tliat occujiy Ihe head of Happy Gulch.

The unconsolidated deposits of Willow Creek valley arc laiely frozen silts and clays, near the bottom of wIiicK are some tliin beds of gravels composed mostly of partly worn fTiiinicrils nf the hard-shale country rock. Many of the pebbles in the gravel are angular, as if they had not traveled far enough to be well rounded, and may be derived from a neighboring bedrock source. In places they rest and grade by mLxture into the broken-up and decomposed hard, shaly bedrock and locally they are mixed with sticky clay. Most of the frozen sediment is a dark-colored carbonaceous material that appears to bo largely derived by disintegration from the shaly country rocks. These deposits vary in thickness from 10 to 25 feet. On top of them lies a cover of several feet of mucky vegetable humus and moss.

prospecting has been done by sinking and drifting on the claims that are located along the pniscnt course of Willow Creek near the low bluffs that border the north side of its valley, but the results obtained have not led to any noteworthy production of gold to date. Along the south side of the chain of claims that extend along Willow Creek from the mouth of Happy Gulch down t) Gold Creek there is located an association group of placer groimd about a mile long named the Haggerty Bench claim, which practically all of the width of the sloping valley bottom that is not included within the creek claims already mentioned. On the lower end of the Haggerty Bench claim, a short distance above and between the ftirks formed by Willow and Gold creeks, an open cut about 12 feet deep has been

Piaceb Mining In Innoko-Iditakod Region. 261

made by groundsluicing to test the value of the deposit. It is reported that this open cut yields about $1.25 to the square foot of surface. The bedrock in this open cut is a shattered hard shale or argillite, commonly called slate, which contains thin veinlets of quartz. The 12 feet of unconsoUdated deposits exposed in the cut are frozen silts and clays. The clays are plastic and difficult to wash. The water for groundsluicing this open cut is obtained up Gold Creek by a ditch that brings it upon the upper margin of the sloping bench at an elevation sufficient to furnish enough pressure for hydrauUcking the deposits with a canvas hose. It is planned to increase this water supply to about double the present quantity by digging a similar ditch from upper Willow Creek and joining the two ditches on the nose of the ridge that separates Willow and Gold creeks.

The placer gold on the lower end of the.IIaggerty bench is probably derived from either one of two sources, or possibly from both of tliem. One source may be the upper part of Happy Gulch, where the presence of gold in considerable quantity is evident, and the other source may be the ridge of altered sedimentary country rock that extends between Willow and Gold creeks from the granitic mass that crosses the upper part of Happy Gulch, although it is not known that the contact-mineralized sedimentary rocks on this ridge are gold bearing. However, if this is the case a concentration of placer gold from the ridge along the south side of Willow Creek valley would be a natural result to expect. In either case the gold that occurs along the south side of the valley appears to have been concentrated in its present position by Willow Creek at a time when it may have flowed nearer the south or left side of its valley. The present position of Willow Creek on the north or right side of its valley gives the impression that the channel of the stream has migrated across its valley bottom from left to right, and even now it is strongly inclined to work northward, as is showTi by the low rock bluffs it is cutting along that side.

Mining Methods.

The mining methods practiced in the Iditarod district may be briefly classified as prospecting and testing, stripping off overburden, excavating the stream-laid deposits and shattered bedrock which contain gold, conveying and hoisting the material to a washing plant, passing it tlirough sluice boxes, removing the angular rock fragments that may clog sluices, and disposing of the tailings.

The prospecting or testing of the placer-gold deposits that have been mined in the Iditarod district is not difficult because they are comparatively shallow, their usual depths varying from 10 to 25 feet. Being shallow, they have been mostly mined by open excavations from the surface. A large part of the ground so far developed is in a

262 MINERAL BESOllRCEH OF ALASKA, 1910.

tlittwcil (;(mdit iuii, but areas of largo and small extent alsO' occur. It is oiily in tlie frozen areas tliat underground or drift mining on bt-drofk may bo done satisfactorily, for wlien tliawed grfjuml is opened the water it generally contains is liable flood workings to such an extent that only expensive pumping will keep tliem free, Kven in open pits seepage water often flows so abimdajitiy that it hns to Iw drained into a sump hole and pumped away. The orifrinal discoveries of goUl in Otter Creek valley were made by sinking small shafts tfl hedmck, and most of the prospecting properties preparatory to mining tlum has been done in this maimer. During the winter of 1909-10 a moderate amount of sinking and drifts ing was done in Otter Valley to test the gold values in the ground, and at one or two localities this metliod has been continued in ft. small way during the summer, biit in general this kind of work haa been handicapped by encountering water in quantities large enough to flood tlie underground excavations. On the upper part of I-'lat Creek some prospecting has been done with a steam drill. Someground was tested near tlie mouth of Flat Creek and on Willow Creek during tlie summer of 1910 by groundshiicing or wasting out opeacuts into the frozen deposits. Theee frozen deposits are mostly ofsiits and clays, the frost binder of which, when exposed to the action of air and running water, rapidly disintegrates them into Sowing slimes that are removed in suspension by running wator. This opencut work, however, can be done only during the sununer, or the season of running water, from May to October, and at localities where sufficient water is obtainable. If prospecting or mining is undertaken during the winter seastm it must be done by sinking to and drifting along bedrock, and if water seeps into these underground excavations in any considerable amount the work is generally abandoned at that jmrticular place. Sometimes a short distance from a thaweil place a solidly frozen spot may be found, where sinking and drifting may bo carried on satisfactorily over a small area without interference by seepage water.

Owing to the shallowness of the gold-bearing deposits of the Iditarod and the largely thawed condition of the ground that contauis the best values practically all the larger ojjcrations so far undertaken have been open excavations from the surface down to and into bedrock. Tliis involves tho meclianical removal and handling, in one way or another, of tho whole tliickness of the unconsolidated deposits and that part of the disintegrated and loosened bedrock which contains profitable amounts of placer gold.

It is generally necessary to remove a variable amount of more or less barren material, such as brush, moss, humus, soil, and sUt, from tho upper of tho unconsolidated deposits. Tliis stripping off of the barren overburden is done by chopping and grubbing away the

Piaceb Mining In Innoko-Iditaeod Region. 263

vegetation and, if running water is available in sufficient quantity and the grade of the surface favorable, directing one or more streams over the 'ground by several channels until the surface material is washed away or groundsluiced. If this work can not be done with running water, horse or steam scrapers are used to move the barren material aside. The steam scrapers are similar to ordinary horse scrapers except that they are of larger capacity and are operated by a system of wire cables and steam hoisting engines so arranged that the scoop is filled by drawing it through the earth and then dragged aside to a dumping ground by a cable attached by a pulley to the top of a stout, securely guyed mast, the scoop being then automatically dumped by a tripping arrangement.

After the placer deposits are stripped of the barren overburden it is necessary to excavate and elevate the gold-bearing material into sluice boxes through which it is washed by water to separate the gold from the sands, gravels, and fragmentary bedrock. In the Iditarod placers the bottoms of the valleys are too flat to allow Unes of sluice boxes to be set up on the bedrock grades and the gold-bearing material to be shoveled directly into them, as may be done in many placer districts. In order to get sufficient grade to the box lines for washing the gold-bearing material and room to dump the tailings from the lower ends of the sluices it is necessary to erect lines of boxes on trestles from 15 to 30 feet high and to elevate all the gold-bearing material to the upper end of the sluice boxes. The hoisting is done by means of a specially constructed sheet-iron dump bucket attached to a running cable that passes through a combination of pulleys mounted in a carriage which runs along a fixed cable that is stretched across the excavation from the top of a firmly guyed mast. This mast is placed so that the upper end of the fixed cable is suspended above a dump box at the head of a line of sluice or riffle boxes. The running cable is adjusted so that the bucket may be lowered or hoisted at different places in the excavation beneath the fixed cable and drawn along that cable to its upper end near the mast, where it automatically trips and dumps its load on an apron or steeply incUned platform. From this the material sUdes down into the upper end of the riffle boxes, to be washed through them by a stream of water conveyed to the sluice by a flume, which, Uke the sluice boxes, has to be elevated on a trestle in order to raise it to the required height.

Steam-boiler equipment varying from 20 to 60 horsepower has been used to operate the hoisting engines at the several plants. This amount of power is considered insufficient by some operators, who intend to install larger boilers in the future. Wood is the only fuel available, and as the supply is none too abundant or convenient it forms a considerable item of expense.

264 MINERAL ItESOURLES OF ALASKA, 1910,

With the exception of the steain hoisting ami scraping of the unconsuUdtktcd deposits as described above, practically all of the work of mining is accomplished by Jiianual labor, from 10 to 60 men being employed in and about the different excavations according to the magnitude of the operations undertaken. Most of the men work in the open pita digging up the gold-bearing material with picks and shovels and conveying it to the hoist buckets in whelban-ows. Sovcriil men are generally required at the sluice boxes to keep the water golil-boaring material properly passing through them. Most of the larger angular pieces of bedrock are not allowed to go through the liffle boxes because they are liable to become wedged Bud clog them. To avoid obstructing the boxes with this angular rock material it is forked out near the head of the sluice after the gold-bearing sediment attached to it has been washed off either by the sluice water or by a stream of water from a hose. The rounded gravel, sand, and silt is washed through the boxes and allowed to stack up at their lower end as tailings. Generally the sluice boxes aie erected high enough above the ground to afford space for the disposal of the tailings by gravity, by occasionally changing the arrangement of the boxes, but in some places the tailings must be moved aside mechanically by a scraper or hoist to prevent" blocking the dump,

JinNING COSTS.

The mining operations conducted in the Iditarod district during 1910, the fii-st year of its development, can not be considered normal, because the district has suffered from the effects of many conflicting conditions such as often attend the opening of a new part of Alaska that is comparatively easy of access. .Tlie first year or so of the development of a new placer gold district in Alaska is generally a period of more or less confusion and luicertainty for both the mining operations and the dependent commercial activities. This is probably more pronounced in the Alaskan gold placers because there the natural conditions arc more severe than in most other countries.

When placer gold is discovered at a new locality in Alaska, if a general opinion that the district olFers considerable mining promise gains popular acceptance, the movement of population to the new locality during the first years of its development is often out of all proportion to its gold-productive possibilities. A condition of overpopulation has characterized the early history of many of the placergold districts of Alaska, especially those which are fairly accessible by summer routes of water transportation, and this condition often continues until a district has passed its period of maximum development. On the other hand, districts which are sufficiently removed from steamboat transit to be difficult to reach are seldom overpopulated, and the

Placer Mining In Innoko-Iditarod Region. 265

mining development of such districts to their full possibilities generally lags for want of sufficient supplies and equipment. This prevents the exploitation of deposits which in more accessible locahties could be mined with a profit that would sustain a considerable population.

As a rule the mining and commercial activities of an Alaskan placergold district, although closely interrelated and intimately dependent upon each other, are rarely in economic harmony. Tliis lack of adjustment often continues throughout the history of a district and is directly reflected in the cost of mining. In most places, especially in the interior of Alaska, transportation is a primary factor governing mining development and is of most vital importance, a high cost of mining generally being chargeable to the lack of cheap and satisfactory facilities for the conveyance of ample supplies from the United States to the placer-gold districts. The mining industry is largely controlled by this factor, for no matter in what part of the Territory mining is undertaken the problem of transportation enters as a primary influence in determining the relation of the mining costs to production, and the difficulty or ease with which a particular locaUty may be supplied with the food, clothing, implements, and machinery required by a mining population determines the possibilities of exploiting deposits of different values. Practically all these suppUes are obtained ready-made from the United States, and the freight charges for their carriage to points on the water routes of transportation, especially in the Yukon Valley, are considerable. The cost of transportation, however, is generally much increased before the supplies reach their final destination, for in most cases it is necessary to move them from 5 to 50 miles overland and the cost of this, especially for large or heavy pieces, such as boilers and hoists, increases enormously with the distance.

Probably it will never be possible to obtain the data necessary to present a complete analysis of the commercial mining condition of a placer-gold district in Alaska, especially for the first years of its development, because reliable evidence in the form of accurate figures is rarely obtainable. Some of the more systematic operatoi-s keep business accounts, but a great amount of placer-mining work is done without keeping records of the costs. The few statements of costs available show that the cheapest mining in the Iditarod during 1910 cost 22 per cent of the production of a particular operation. Another comparatively low-cost operation was performed for 32 per cent of the production. These costs are the lowest reported. On the other hand, much of the mining so far done has cost 70 per cent or more of the production. The general average cost of mining in the district for the season of 1910 probably was between 50 and 60 per cent of the total production. The cheapest operations are much below the

266 MINERAL RESOURCES Df AlvAaKA, 1010.

average of tlie district mid me ijriibtilily iietirly na low as will ever bfr accomplished by the methods used, jVlthough costs may bo reduced if conditions become better balanopd, sucb results probably will be Attained only upon small tracts of favorably situated ground. Th deposits mined at the lowest costs ciletl above are about 10 feet deep and rest upon a soft bedrock of deeply decomposed granitic rock that may be readily scraped up and very easily waslied after an ovei-burden of muck and silt is removed by groundsluicing. The actual cost of mining this deposit was about 128 cents per cubic yard. This is as low as the cost of some dredge mimiig on Seward Peninsula, , where the lowest cost of placer-gold cfredguig so far attained is 18 cents per cubic yard. In the Iditarod district it will cost considerably more to install and ojierale dredges than on Seward Peninsula, as transportation and fuel will be far more expensive, so it is doubtful if dredge mining can be conducted in the Iditarod for 18 cents per cubic yard. I

The possibility of placer-dredge mining on considerable tracts of flat-fying stream deposits that cover the valley floors of Otter and . Flat creeks, wliith are presumed to be gold bearing to a greater or lesser dree and extent, has been discussed in a preliminary manner by some of the persons in ground on these creeks. Sucli an enterprise should not beimdertaken without first setruring a satisfactory community of interests for considerable tracts of pJiR'er ground and prospecting them thor.iughly enough to determine the extent and thickness of the gold-bearing beds, so as to enable reliable estimates to be made of the amount of gold that occurs, with known quantities of the material to be by a dredge, including the barrenoverlyingdeposits with which the gold-bearing material is associated. Due allowance must also be made for the dilliculties that may be encoimteretl by dredge buckets in digging up the shattered bedrock, in the cracks of which much of the gold lies, and also in handling the bowlders wliich are present in the deposits in considerable numbers. Experienced dredger men should be consulted before such an investment is made.

Commendable energy has been shown by the real mining element of the Iditarod district in overcoming the obstiudes the mining situation presented to them; for the camp, so far, never lias promised to produce enough new wealth to satisfy even the reasonable expectations of all the people who have interested themselves in the district in various ways. Before June, 1910, very little was definitely known about the occurrence of the placer gold and there was not an adequate supplyof mining equipment at hand with which to work, but after the season opened no time was lost in commencing operations which

Flaceb Mining In Innoko-Iditarod Region. 267

would demonstrate the mining possibilities of the district. The necessary boilers, hoists, etc., with which to perform effective work were brought to the head of steamboat navigation on Iditarod River and thence moved with considerable difficulty and expense to the better-known placer tracts on Otter and Flat creeks, where they were quickly installed and actively operated without delay until the freeze in October.

When it is considered that the district has been greatly overpopulated by a class of persons whose intentions are not to mine but to gain indirectly from the results of the miners' labor, the first season's gold production has been as large as could be expected. Of the 2,500 persons who entered the Iditarod district during 1910 not more than 1,000 engaged in work directly related to its mining development. The remainder, or much over half of the population, had no other intentions than to engage in parasitic pursuits of minor importance to mining, and it is probably unfortunate that the district has been thus overburdened, especially by so many persons who have shown overenthusiasm in town-site booming and kindred speculative enterprises.

The gold output of the Iditarod for 1910 amounts to about $500,000 in value, of which about $200,000 may bo credited to Otter Creek and the remainder, $300,000, to Flat Creek. There was also a few thousand dollars' worth of gold mined from Black and Willow creeks in the course of preliminary development work.

Outlying Placer-Gold Localities.

The one significant result of the overpopulation of the Iditarod has been to stimulate a widespread search for placer gold throughout the surrounding territory, particularly south of the present center of mining on the headwater branches of largo streams that flow into Kuskokwim River from the divide that separates them from the Iditarod drainage. The results of this movement, which during August and September, 1910, was participated in by over 500 men and reached the magnitude of a ''stampede," indicate that prospects of placer gold occur in several areas of moderate extent within the valleys of Moore, Jualin, Donlin, and Crooked creeks, which are south of and opposite the headwaters of Otter and Bonanza creeks. Prospects are also reported to occur on Little Creek, a tributary of Iditarod River about 75 miles above Otter Creek. Although there appears to be little doubt that some prospects of placer gold have been discovered at particular spots of small extent on several of the smaller tributaries of the streams named above, it is not possible at this time to make any definite statements about the extent or richness of these new gold-bearing areas. The men who participated in this stampede movement did not apply their energies toward making or verifying discoveries of placer gold, but, after the

268 minebaij resources of aiaska, l9lo.

manager dow commoiily practiced nil over Alaska in such cases, they devoted practically all their time to traveling rapidly over the coun- I try and hastily placing location stakes and notices so as to embrace -vast tracts of land for placer mining without making any effort to B determine its gold-bearing character (a primary requisite of the ' law), simply assuniiiig that placer gold may possibly occur in some of the ground located from the meager fact that there may be an actual occurrence known within several miles, perhaps in the siuae valley or some adjacent basin. Oftentimes, however, not even tliia small stimulus is considered essential, the optimistic imagination characteristic of the gold seeker being enough to make liim think that, to use the common expression, "the country looks good." Ipdeed, the cu.stom of making wholesale locations of land in the form 'of countless association-group claims of 160 acres each, for the ostensible purpose of placer mining, has become so general throughout Alaska during the lust four or five years that it is now unusual in many districts to find ground located as single 20-acre claims. It is not uncomjuon for several men in partnership or even one individual, sometimes provided with powers of attorney of a number of absent persons, to claim by priority of location from '25 to 50 and . occasionally as many as 100 association-group claims of 160 acres — in other words, to make ridiculous claims of intentional mining rights on .0,001) to 1 iifre of tlio domain. The manner in which this practice appears to be countenanced by Alaskans gives ground thus falsely claimeil a sort of concessionary value that is considered as an asset, by which claunants ho])c to profit if by chance a genuine discovery of gold ia eventually made upon or near some of their illegal holdings. It is a matter of common knowledge throughout Alaska that no actual discoveries of gold are made on 90 per cent of the claims staked when they are first located for placer mining, The apparent purpose governing the whole matter is to first get what is considered a prior control of largo tracts of land with the idea that gold may bo discovered upon some of it afterward, which discovery may then be turned to the financial advantage of the per sons who claim priority of location but who have done nothing to deserve reward. In brief, the prunary object of the mining laws, whose intent is to encourage citizens to search without restriction for mineral wealth upon the public domain and, if thoy actually dbcover it, to protect their rights as individuals therein as long as they ve evidence of reasonable interest in the exploitation of such mineral wealth, is utterly ignored. The exploitation of Alaska's placer deposits at the present time is apparently suffering fiom the chaotic condition brought about by an utter contempt for both the mining laws and the common rights of the public in the matter.

Popular opinion throughout Alaska seems to strongly denounce the abuse of tlie locating privilege by the unrestricted use of poweia

Piageb Mining In Innoko-Iditarod Region. 269

of attorney and association-group staking. The personal opinions expressed by most individuals are to tlie effect that such methods should be aboUslied, yet they do not intend to deny themselves such privileges as long as they have no guaranty that others will not take advantage of them.

Conclusion.

At present it is not possible to make conclusive statements regarding the future mining possibihties of the Iditarod district. During the summer of 1910 enough experience was acquired with the placer deposits on Otter, Flat, and Willow creeks to define fairly well the character of the unconsoUdated stream deposits where mined and the conditions surrounding the occurrence of the placer gold in tliem. The work performed shows that there is a general similarity in the kinds of unconsoUdated deposits on these three streams, but there are some variations in tlie relative proportions of the finer and coarser materials, in tlieir tluckness, and in the presence or absence of perpetual frost. All the deposits belong to the class of shallow placers, which may be best mined by open surface excavations.

Though considerable prospecting has been done to determine the extent of the placer-gold deposits and though their hmits of distribution on Otter, Flat, and Willow creeks seem to be well defined in some directions, it can not be stated now with any degree of certainty how extensive they may be or how much gold they may contain. It may be said, however, that the mining situation on these three creeks is well in hand and without doubt will soon adjust itself to the conditions surrounding the occurrence of the placer gold. No doubt more ground may be mined with a profit in the future than would have been possible under such conditions as were prevalent during 1910.

From wliat is known of the occurrence of placer gold in the Iditarod and the adjacent districts of Innoko and Tuluksak it appears probable that there ma}' be other similar but separate areas of auriferous minerahzation of moderate extent distributed in a more or less scattered manner tlu'oughout the central part of the Kuskokwim Mountains. Li this provmce the indications seem favorable for the discovery of gold-bearing stream placer deposits at or near mineralized zones of contact of granitic mtrusive rocks with the sedimentary formations. These areas, however, do not appear to form a continuous gold-bearing belt.

The probable future expansion of placer mining in this region will depend chiefly upon the discovery of more occurrences of local goldbearing mineralization in the vicinity of intrusive masses or dikes of granitic rocks such as are known to occur at several places along the Kuskokwim Mountains from tlie headwaters of the Innoko and Tuentna on the northeast to the Tuluksak on the southwest. At this date several new gold-bearing localities of this kind are reorWL*

MINERAL. RESOURCES OF ALASKA, Ifil

Those nearest tlie Iditarod on Jualin, Donlin, Crooked, and Litllfl creeks have attracted the most attention, but portions of the valley of Moore Creek, a headwater branch of the southwest fork of tha Takotna, and of the large northeast branch of this river, whicli ia called tlie Tuontna or Nbcons Fork, have also aroused enough interest to be extensively located upon in the customary wholesale maimer for placer mining. The residta of prospetting that will be carried on at all these new localities during the present year will be voty important in determining the extent and activity of placer mining tlirougliout tlie Kuskokwim Mountain region.

Northward from tlie lunoko district the Kaiyuh Mountains may prove a good field for prospecting, because granitic intrusive rocks simUar in lithology to those that appear to have brought about the auriferous mineralization of the Innoko and Iditarod districts are known to occur there at many localities.

The Shijngnak Region, Kobuk Valley.

By Philip S. Smith and Henry M. Eakin.

Introduction.

In the central part of the Kobuk River basin there is a mineralized area in which placer gold has been mined and copper, gold, leadsilver, and asbestos deposits prospected. These deposits had not been studied by members of the Survey before 1910. The region was the scene of a stampede of gold seekers in 1898, but although a few thousand dollars in gold was produced annually for several years, in 1910 the district was nearly deserted. Many problems of importance both to the prospector and to the geologist still remain to be solved by more careful examination, but until such studies are made it has seemed expedient to set forth the general geologic observations and to point out some of the important subjects that require further investigation.

The region considered in this report lies north of the Arctic Circle, adjacent to the 157th meridian. Particular attention is given to the region between Kogoluktuk River on the east, Shungnak River on the north and west, and the Kobuk on the south. Altliough this small area is the place where minerals of economic importance have been found and is directly the subject of this report, a somewhat larger region is described in order to show the setting or general relation of this field to the geology and geography of the central part of the Kobuk Valley. A still broader and more comprehensive account of the features of northwestern Alaska is in preparation and will serve to extend the area covered by tliis more detailed report.*

Geography And Topography.

Figure 19 shows the general location of the area, which for convenience vnH be called the Shungnak region. The settlement from which this name is taken is about 250 miles from the mouth of the Kobuk, measured along the crooked course of the river. Measured

1 Smith, P. S., Geology and mineral resources of northwestern Alaska; In preparation.

The 8Hungnak Begion, Kobuk Valley. 273

in a straight line, however, it is only a little more than half that distance. Throughout this distance the stream is navigable for boats drawing as much as 3 feet, and an even greater draft could be carried if it were not for shallow bars at the mouth of the river and the crooked, shifting course of the channel farther upstream. The best approach to this region is by way of Kotzebue Sound and Kobuk River, for a mail boat from Nome touches at Kotzebue three times a month, and launches and barges can be taken there for points up the river. A description of the method of reaching Kiana, at the mouth of Squirrel River, is given on pages 306-309 and appUes to reaching Shungnak as well, but the river trip continues for another 175 miles and consequently takes from 5 to 10 days longer.' In 1901 Mendenhall reached this region by way of Koyukuk and Alatna rivers, and this route has been traveled by natives and prospectors for many years. This is, however, a roundabout way of reaching Shungnak and is not suitable for bringing in supplies, etc. In 1910 the writers reached the region by going overland from the Koyukuk near the mouth of the Hogatza, but this is not a direct route and is not a feasible way of reaching the Kobuk except during the winter months.

Belief.

The larger-scale map (PL XII) shows more details of the Shungnak region than are given on the sketch map (fig. 19). Although the topography of the map shown on Plate XII is in a measure obscured by the patterns used to denote the several geologic formations and groups, the major features of the relief are evident. From this map it will be seen that there are five more or less distinct belts of rehef . The most southern of these belts is a range of hills, averaging about 2,000 feet in elevation, succeeded toward the north by the Kobuk Valley Flats. These are in turn succeeded by a narrow range of hills reaching heights of about 3,000 feet in the eastern part and gradually decreasing in altitude toward the west. North of these hills is a lowland 3 to 4 miles wide which is succeeded toward the north by rugged mountains.

The southern hills, called by Mendenhall in 1900 the Sheklukshuk Range, form only a narrow highland between the Kobuk lowland and the Selawik lowland on the south. These hills have been only slightly explored, but they are probably not more than 10 to 15 miles wide and trend in a general east-west direction. The higher points reach elevations of 4,000 feet, but the average elevation is only about half as great.

The Kobuk lowland, so called from the large river which traverses it, is from 10 to 15 miles wide and has an average elevation of 200 to 400 feet above the sea. The highlands which bound this lowland to

W319**— BuU. 480—11 18

SM mineral resources of ALASKA, 1010.

the north and smith rise rather abruptly from the nearly featureless plaui and enipliastze by tlieir sharjiness the plain's slight relief. TIio flood plain of the Kobiik occupies a width of several niUea along the eeiifreJ part of the lowlanda, distinguished by the occurrence of lerous bayous and cresccntic hikes marking former coui-ses of tlic river. The higher parts of the lowlands on either side slope fmiu the bordering hills tlic river, descending to the slightly lower level of the flood plain with more or less distinct bluffs. The surface of such parts of the lowlands is not altogether smooth, aa locally thero are lakes of irregidar shape and small size.

North of the Kobuk lowland, as already noted, a range of hills, in places 3,000 foot or more in height, rises abruptly and forms a strip of highland 10 to 12 miles wide toward the east but gradually narrowing toward the west as it approaches tiio junction of the Kobuk and the Ambler. No name has been given to these hills, though tlie\- uj)- pear to the continuation of Lieut. Stoney's Schwatka Mountains.' Owing, however, to the misconception that aa tn the general topograpliy and to the tact that tlie name as applied does not septirate tliis front range from the mam ranp;e to the north, it has been proposed to call the feature above described tlie Cosmos Hills. This name is given because Stoney's wintfip camp on the Kobuk was called Fort Cosmos and the stream near his camp, wiiich heads in lliese hills, wns also called by this mime. These hills are characti'ri/,cd liy a !:; east-west trend but are considerably (hssected, so that the liigher points are irregularly distributed.

Beyond the Cosmos Hills is a lowland not so extensive as the Kobuk lowland but still a marked topographic feature. To, the west this lowland is drained by Ambler River, but to the east it is traversed by Shungnak and Kogoluktuk rivers and it persists even farther east, if scattered observations reports are to be trusted. Even where it does not contain a laie scream this lowland is stil) presen-ed and it is believed to he a significant structural feature. A particularly clear illustration of a portion of the lowland without existing streams is shown by the area between Ambler and Shungnak rivers, At this place the distance between the two streams is about 3 miles and the elevation of the divide between the two is not over 200 feet. In order to have a short descri]>tive term for tlus feature it will be called the northern lowland.

North of the northern lowland the mountains rise steeply to heights of 3,000 to 4,000 feet above the main streams, so that their relative relief is strong. Only the southern margin of these moimtains is included witliin the mapped area. P'rom a study of Stoney's map it is evident that this highland belongs to the group of hilla named by him the Baird Mountains, and by this name they will be

U. 8. Beologioal Survey

Sua, BnTri.ind lilt. ftuvutllc. lacmthne.

Oej

Thb8Hungnak Region, Kobuk Vaisley. 275

called in this report. Serrate crest lines and deeply intrenched valleys characterize these mountains and give a rued, hospitable appearance to the landscape.

Drainage.

The drainage of the Sljimgnak region presents a number of different types of streams, many of which have a complex history. The master stream is the Kobuk, wliicli heads in the hills far to the east and flows westward, receiving tributaries that head in the higliland areas along its course. The Kobuk is a large river, having a width near Shungnak of 600 to 800 feet and a current of 2 to 4 miles an hour; the depth varies, being in many places as much as 15 to 20 feet. It has a meandering course tlirough the lowland and many of its deserted channels' form sloughs and oxbow lakes. The strength of the current is sufficient, however, to make it an easy river to descend, and above the delta even one unfamiHar with the river finds little difficulty in avoiding blind channels. Within the mapped areas there are no rapids or treacherous stretches.

Kogoluktuk, Shungnak, and Ambler rivers are the largest tributaries to the Kobuk from the north. All these streams head in the Baird Mountains and flow in glacially sculptured valleys, receiving many tributaries until the southern face of the mountains is reached. Thence they traverse the northern lowland and then flow in rocky canyons through the highlands of the Cosmos Hills, later traversing the Kobuk lowland to join the main stream. This course, transverse to the dominant geologic structure and also to the topographic structure, indicates the complex history that made such drainage possible. Some suggestions as to the origin of this peculiar drainage are given on page 287, where the course is explained as in large measure due to glaciation and structure.

All these streams carry laie volumes of water during the early spring and summer and with the exception of the easternmost are not fordable during ordinary seasons. Owing to their heading in the high mountains they derive a large amount of water from melting snow and so maintain a more constant flow than the streams not having a sunilar supply. In the highlands their courses are comparatively straight, but in the Kobuk lowland some of them meander m irregular curves. Low falls and rapids occur on these streams as they the Cosmos Hills ; in fact, the name Kogoluktuk is said to mean in the native language "river with falls."

The larger streams entering the Kobuk from the south have not been explored, and little is known of their geography except from the reports of natives. Kuikcherk, Pick, and Black rivers are the three largest streams, and probably all of them head in the Sheklukshuk

276 Mineral Besoubces Of Alaska, S

Kanti'. Tliey are smaller than tlie nortliLTii Iributarics because tliry (Iraii) siaallcr ba.siii3 and also because tho lower hills in which they licad are not so effective in anow storage as the higher Baird Mountains to the north. In their lower courses these streams are rather sluggish and their water is in large measure derived from the tundra which they flow. The dark swamp water Is suggested by the name Black River, given by Stoney in 1886 to the westernmost of t'lese streams.

In addition to the larger tributaries there are many smaller st retina originating in the higlilands and entering the main stretun indejieudently or joining one of the larger branches. The streams from the Cosmos Hills show many intricacies, as they join the transverseflowing streams, such as Kogoluktuk and Shungnak rivers. Thus munv streams beading on the north side of these hills flow northward to the northern lowland or a transverse stream, where they turn abruptly and ci-oss the range and thus enter the Kobuk. One of the best examples of this feature is Ruby Creek, which heads within 3 to 4 miles of the Kobuk lowland but flows northward for 7 to 8 miles before joining the Shungnak; thence its waters are carrietl southwest for about 20 miles before reachuig the Kobuk. Tliis condition |)revails in spite of the fact that near its head there is to the south a pass not over 400 feet above the Kobuk, which has evidently been occupied by former <drainage.

Passes similar to the one described at the head of Ruby Creek, although at somewhat higher elevation, are found at the head of many of the otlier streams. For instance, Cosmos Creek heads practically on the southern slopes of the northern lowland hut flows southward across the range to join the Kobuk. These examples serve to show that many of the valleys through the Cosmos Hills liave been eroded by agencies other than the existing streams and that the present rivera have had their courses in large measure determined by this earlier topography. It is believed that these passes and transverse valleys are best explained not as due to antecedent streams which persisted or failed to cross the Cosmos Hills hiring the possible deformaticm of the region but as due to drainage mod ideations induced by glaciation in the Baird Mountains and contiguous territory in comparatively recent time.

Climate.

There are but few data as to the metcorologic conditions prevaolii in the Shungnak region, though there are more observations here than in other parts of the Kobuk Valley. Mendenhaii summarized the available temperature observations as follows:'

am Fort Qamliu U KotHbue Sound, .AlBsku I'ral. Fet U. 8. ,

The Shunqnak Beoion, Kobuk Valley.

Summary of temperature observations on Kobuk River 1885-1899.

Dato

July

August

August

September.

October

Novem!)er. December. .

January.. February.

March

April

liay

June

July... August.

February.

Minimum.

-G5

Maximum.

ti8 ti8

a5

Mean.

Authority.

Lieut. Stoney.

Do. W.L. I'oto.U. S.Geol. Survey. Lieut. Sidney.

Do.

Do.

Do.

Do. Do. Do. Do. Do. Do.

McElwaine. Do.

As the mean annual temperature of the region is far below the freezing point, the presence of ice exerts an important control on the length of time that placer deposits can be worked. Snow may be expected in the highlands during almost any month of the year. According to Cantwell the hills west of the Ambler were snow covered on August 9, 1885, and in 1910 the hills above 2,000 feet in elevation east of the Kogoluktuk were covered with snow on July 20. In 1885, according to Stoney, ice had formed on most of the small streams by September 23 and along the main streams by the 25th. Bv October 18 the main river was frozen so that it could be crossed. Freezing continued until in February the ice had a maximum thickness of 5§ feet. On May 19, 1886, the ice along the banks of the Kobuk began to crack, and by June 6 of that year the river was free of ice. Joseph Grinnell, who spent the fall of 1898 and the spring of 1899 a little west of the vShungnak region, reported that on October 15 the Kobuk was full of ice and by the 21st the ice was a foot thick. In the following spring the ice began to break on May 24, and by the 31st the river was free. It should be noted, however, that while the river itself breaks by June 1 , Sound remains frozen until the first week or so of July, and therefore communication with the outside world is seldom established the later part of July or even the first of August.

No instrumental determination of the precipitation is available and but few observations even as to the number of rainy days have been made. W. L. Poto,* a member of the Mendenhall party, is

CantweU, J. C, Exploration of the Kowak River, Alaska: Report of the cruise of the Revenue Marioe Steamer Cctwin in the Arctic Ocean in the year 1885, Washington, 1887, p. 47. t Stoney, O. M., Naval exptorationa in Alaska, Annapolis, 1900.

Orinnell, Joseph, Gold hunting in Alaska, Chicago, D. C. Cook Publishhig Co., 1901, pp. 7-84. MfgMtonball, W. C, op. cit, p. 65.

278 Mimebal Resources Of Al.1Ska, 1910.

as recrdin}; 15 rainy daya during August, 1885. and McEl- 1 wuuie ' reported for June, July, August, and September, 189S, 19,, 11, 18, ami 12 rainy days, respectively. During 1910 the autlioisj were in the Shungnuk region from July 22 to August 11, inclusive. 1 and the number of rainy days and duration of precipitation were a follows :

PrtdpiUaion in the Shwtgnat ngion. July ?,' to Augutt II. 1910.

July 22 Shovera and rain.

July 21 Haui in evog.

July iR Rbui all day.

July W Bain all day,

July 26 MUland min; heavy ruin in cvinint;.

July 20 Rain.

July 30 Heai'yTnist in moniinj;.

AiiR. 2 Rain.

Autc. -.Ruin in morning; ehowem in Hfumoon.

Aug. 4 Heavy iiiiAt and rain,

Aii. S Ruin and heavy misl.

AuR. G -Rain.

Aug. 7 Riiin.

Aug. 8 Throatpning in mominR; cleared later.

Aug. 9 Rain all night; foggy in morning; showers in afternoon.

From thia it will be seen that of the 21 days spent in the Shunnak region 15 were marked by showers or rain. It should, however, he noted that last year was exceptionally wet, and therefore tlie figures by no means represent average conditions. There is, on the other hanoi, hitle room to doubt that most of tlic preeipitation comes during tlie summer, so that July and August are usually the wettest months

Vtigetation Ani} Andials.

Owing to its high northern latitude the Shungnak region has a typically subarctic flora. Timber is hind mainly along the laier streams and does not extend on the mountain sides to any considerable elevation. Spruce and hinh are practiciiiiy tlie only trees that grow to suiiicient size for lumber, and only spruce is large enough for cabin logs or sluice boxes. Stoney notes that the largest sjiruce tree seen by him in the whole alley was near Cosmos Creek. It measured SO inches in circumference at the base and 68 inches at a height of 6 feet above the ground and was 80 feet tall. This was an unusually large tree, however, and the average spruce docs not exceed a foot in diameter. In the higher parts ot the region even spruce is wanting, and the pros|>actor is compelled to resort to scrubby willows and nlilers for fuel.

Berries are exceedingly on the unforestcd slopes of the highlands and on manj- parts of tlie lowlands. Blueberries are

Uendeoli&ll, W. C.op. dt., p. M. 'SUuwy, 0. U., op.dt., p. 83.

The Shungnak Begion, Kobuk Valley. 279

particularly plentiful on the higher parts of the Kobiik lowland where trees and bushes are absent. Salmon berries are found on all parts of the lowlands and are so plentiful that people and animals depend on them for food. Some currants and cranberries were seen, but they are not as abundant as the two other kinds of berries.

Grasses for stock are found on the lower hill slopes and on the surface of the lowlands. Mendenhall notes rye grass, blue grass or redtop, and a variety of bunch grass as the more usual species. Horses show a strong liking for the so-called goose grass, an equisetum, but it seems to contain little nourishment. The grasses flourish particularly in the neighborhood of the old settlements and camps and quickly spring up in the burned-over areas. None of the grasses seem to stand frost well and all appear to wither and lose their strength-giving qualities as soon as freezing nights begin. This is probably due to their exceedingly quick rank growth.

There are but few game animals now in the Shungnak region except bear. These are found mostly back in the hills or along the unfrequented streams. Both black and brown bears are reported. Caribou have been shot at several places within the region, but they are not numerous and the natives have to travel far to obtain their supply. There is, however, a herd of reindeer in the Sheklukshuk Hills and strays from this herd have probably been taken for wild caribou. Small fur-bearing mammals, such as fox, mink, and marten, are occasionally caught, but they are found in no great numbers and are becoming scarcer each year.

Fish are abundant in almost all the streams. Salmon is one of the most important food supplies. These fish are particularly abundant in the Kobuk and during the last week of July and the early part of August native fishing camps are established at several places, especially just above the mouths of Kollyoksok and Black rivers. A large white fish, known to the natives as ''she,'' is also caught in the Kobuk and is much prized for food. Grayling can bo found in almost all the side streams and mountain brooks. Trout, probably salmon trout, weighing as much as 3 or 4 pounds each wore caught in Dahl Creek and are reported from many of the other streams.

Many birds are found in the Shungnak region. Most important for food are ptarmigan, spruce hens, and ducks. Owing to the cold climate these can be kept for months during the winter without spoiling. Beside these game birds many song and other birds are either smnmer visitors or Uve permanently in the region. Grinnell gives a list of the birds wintering in the region near the mouth of the Ambler, noted by him, as follows: Pine grosbeak, redpoll, spruce grouse, ptarmigan, three-toed woodpecker, jay, and chickadee. The

1 Mendenhall, W. C, op. cit., p. 57.

Orinnell, Joseph, Gold hunting in Alaska, pp. 68-60.

;.

280 Mineral Resources Of Alaska, 110.

same writer states tlint tho first bint from the south arrived in 1899 on April 22. After that diite many familiar birds, sutli as s|)arrows, thrushes, sandpipers, robins, loons, and blackbirds, came to tho rogioa for tlie suniracr.

Bettlekents And Fofttlation.

In 1910 there were only about a dozen whito ptiople in the entire Shuinak region, though in 1S98, when a rush to the Kobuk was in progress, there were several hundred. Tlie only village at the present time is Shungnak, where the Ignited Stats proramiasioner and r£M?order for tlie district formerly lived and where a post office is moiutAined during the six winter months. A Friends mission has also located there. Tho town is the headcjuarters of the Government schoolteacher and superintendent of tlie reindeer herd. Tliere is a smaQ store kept by a trader, bnt usually not many supplies are kept in stock, so that by tlie end of the winter they are practically exhausted. Around this white settlement a group of native camps has grown up and before the fishing season commences over a hundred natives are settled witliin a short distance of the white men's cabins.

Tliree or four prospectors are now on Dahl Creek and Shungnak River, On the former stream four or five cabins, several of which are now deserted, are located near the soutliem face of tbA Cosmos Hills, and on Shungnak River is a similarly located cabin. On Dahl Creek, 2 miles or au above the lowor cnbius, are prospectors' camps. These are the only inhabited white men's cabins in the region, but there are many others now deserted along both the Kobuk and its tributaries. Some of these deserted cabins are located as follows: \ear tho head of Riley Creek, near the forks of Ruby Creek, on tho slopes of tho valley of the left fork of Ruby Creek, on Wesley Creek, near the lower end of tho canyon, on the lower part of the Kogoluktuk, aud at scattered intervals along the Kobuk, the largest number at any one place being near the mouth of the Ambler.

The largest settlement of natives is, as already noted, near Shungnak, but there are also smaller settlements along the Kobuk. The largest of these is probably the one called Kalla, near the mouth of Kollyoksok River. It is inijiossible to give any accurate estimate of the native population, for during the summer many are away on hunting or fishing trips or go down the river to Kotzebue. Mr. Robert Samms, the missionary' on Kotzebue SoumI, after a careful estimate during the winter of 1898, placed the number at 500. According to the governor's report for 1910,' the enrollment of children at the Shungnak school during 1909 was 61, and this of course represented only a small part of the native jmpuiation of even the Shungnak region.

Report o( tlw goTemor ot Alaska lor iX9, Wasblngton, 1910, p, 20.

The Shungnak Begion, Kobuk Valley. 281

Most of the travel in the region is by boats during the summer and by dog teams during the winter, so that good trails are more or less lacking. However, owing to the need of communication between the mining camps and Shungnak during all seasons of the year, the United States commissioner wisely had certain prisoners build a trail from the town to the upper placer diggings on Dahl Creek. Another trail has been built from the Kobuk, near the mouth of Wesley Creek, to the mine near the forks of Ruby Creek. A boiler was taken over this trail by dog team in the winter, so it has been well leveled and brushed out, but it is not very good for summer travel. Connecting with this is a well-marked trail from Dahl Creek to Wesley Creek along the southern slopes of the Cosmos Hills.

These are the only marked trails in the region, but horses may be taken through the hills or the lowlands back from the larger streams by one experienced in Alaska travel. The Survey outfit was carried by pack animals, and it was possible to go practically at will where the work required.

Descriptive And Historical. Geology.

General Statement.

Only a small part of the Shungnak region has been seen in detail, so that the description of the geology is necessarily confined to the larger subdivisions, and no attempt has been made to map more than three main groups into which the rocks and surface deposits naturally fall. These are the metamorphic rocks, both sedimentary and igneous, the Mesozoic and Tertiary (?) rocks, and the unconsoUdated sands, gravels, and glacial detritus. Such a classification serves not only to differentiate the rocks on lithologic and textural grounds, but it also places them in historical order, beginning with the earliest and closing with the latest deposits. Not only are the geologic features described, but the history of the region is traced as far as the structure and lithology give insight into past conditions.

Metamorphic Bocks.

The oldest rocks in the region belong to the metamorphic complex. The greatest areas of this group are in the Cosmos Hills and the Baird Mountains. In these localities several hundred square rniles are underlain by these rocks. In the highlands south of the Kobuk these rocks do not occur, but they are believed to extend for several score miles north of the mapped area, and east and west they probably continue uninterruptedly from Seward Peninsula through the headwaters of the Koyukuk to the Yukon. Rocks of different

The efficient and competent manner in which the Survey horses were taken through the region was due to the untiring activity and sldU of the head paclcer, A. O. Winegarden, of Montana, to whonv writen design to publicly oximbss their thanics.

282 MINERAL EE60UECES OF AI.ASKA, I'JlO.

composition, age, and miles of origin aiv together in this metamorpliic complex, wliich is termed a complex mainly becnuae so little work has been done to determine its stratigraphy rather than because it is undetenninable. Both sedbnentary and igneous rocks are represented in this group. Though the former occupy a greater area, it is impossible as yet to state the relative proportion of e-ach.

Tlie sedimentary rocks of metamorphic character are quartzoae acliists, crystalline limestoues, and shearetl conglomerates. Tha quartzose scliists, as their name inipUes, are composed mainly of quartz and mica or elilorite. They can not be distinguished by the eye from many of the rocks of Seward Peninsula, The amount of aiit'aring antl attendant nietamorphisra has hail an important effect upon the physical character of the rocks; thus in pl&a they schistose, with wavy or knotted fleavagc, and secondary minemlsi such as mica have been but sparingly develojwd. In this group ars the black grapliitic quartzose slates so commonly found in the vicinity of the productive placers in Seward Pemnsula. Slates and schists of this tjpe are found near tlie lower placers on DahJ Creak where the stream leaves the Cosmos Hills and on the divide between that stream and Riley and Ruby creeks. Smaller areas are also found at other places and there seems to be a rather close cotmectioD between this rock and the placers. In most places there are a great number of qiiailz veins and in the griipliitic shit's and scliists, ranging from microsco]>ic filaments to masses 2 or 3 feet in width and traceable for several liundred feet along the strike. Veins of this sort are particularly numerous on the divide between Dahl and Riley creeks, and the whole hillside from the divide to the latter stream is with a heavy quartz float, many of the pieces weigliing a hundred pounds or more.

Bluish-white crystalline limestones are closely associated with the schists of sedimentary origin. Tiiey also have been deformed, and thoir irregular distribution clearly indicates that they have been subjected to pronounced dislocation. It is therefore not always possible to make out with certainty their relations to the other metamorphic rocks of the region. In the area between Wesley and Ruby creeks it is certain that the limestone overlies the black slates and schists, and the Slime relation is shown on the central part of Dahl Creek. There is, however, a possibility that the up[)arent relatiim may have been induced by faulting, so that the stratigraphic succession may not be as suggested.

No ilefinite information as to the age of the limeslones was obtained, as fossils have been in huge measure dcMti-oyed by metamorphism. In the Iloat in the central part of Dulil Creek, not fur from an outcrop of a down-faulted block of limestone, indistinct corals were found ia a limestone bowlder. These were too poorly preserved to permit

The Shungnak Begion, Kobuk Valley. 283

specific determination but were of precisely the same appearance as fossils collected in 1909 from the Umestones along the eastern flanks of the Darby Range in southeastern Seward Peninsula that were identified as Devonian and Carboniferous.* Another similarity between these limestones and some of those of Seward Peninsula was the strong petroUferous odor emitted when freshly broken. The limestones with these particular characteristics were dark, nearly black in color, with interlaminated bluish-white bands, the whole somewhat crystalUne.

The schistose conglomerates that were observed in the region are especially developed in the southern part of the Cosmos Hills. In this locaUty the conglomerate occupies a strip about 2 miles wide trending in a general east-west direction and has a southward dip. Although the relations to the other metamorphic rocks are not perfectly clear, the direction of dip indicates that the conglomerates overUe the schists and slates. Further evidence in support of tliis interpretation is aflForded by the fact that recognizable pebbles of black slate and of chloritic schist, together with nimierous quartz pebbles, make up the conglomerate. These pebbles prove by their presence that schists and slates with quartz veins were in existence and had been eroded before the deposition of the conglomerate, and they suggest an unconformable relation between these rocks and the conglomerate. No pebbles of Umestone were recognized, and the structure is not sufficiently definite to prove whether the limestones antedate the conglomerate or not.

On the succeeding page another conglomerate is noted, but it should be distinctly understood that the one described above and included in tliis section deaUng with the metamorpliic rocks is thoroughly sheared and schistose tliroughout its extent and can in no way bo explained by the small amount of deformation to which the later-described conglomerate has been subjected. Not only have the pebbles composed of the softer rocks been deformed, but even the quartz pebbles have been pulled out and elongated, so that now they are many times their original length. Many pebbles 3 inches long were recognized, but tliis measurement, however, should not be interpreted as sho\\dng maximum distortions, for by excessive elongation the pebble form becomes more and more obUterated, so that finally it can not be recoguized.

Igneous rocks that have been subjected to pronounced deformation and consequent metamorpliism have also been recognized in the Shungnak region, but the exposures examined were poor. An outcrop of greenish scliists belonging to this group extends for some distance along the ridge between Cosmos and Wesley creeks a mile or

Smith, P. B., and Eakin, U. M., Geology of soutbeastni Seward Peninsula and the Nulato-Norton Bay region: Bull. U. S. Oeol. Survey No. 449, 1911, p. 48.

284 MINERAL RE80UECES OK AlSKA, 1910.

SO south of Iron Mouottiiii. It appeara cut Uic underlying slatfl nnd forms a sill between that rock auti tho overl_\"iug limestone. So ffir as observed it docs not cut the liutcstono nor does that rock show any contact effects. however, lina proceeded to such' lengths that these criteria are not defmitjve. These older igneous rocks have a schistose structure, are greenish in color, and consist m&iiilj of greenwh chlorite and plagioclase feldspar, the latter as a rule completely They boar a close resemblance to the nirtitmorphic green.stone schists of Seward Peninsula and are believetl toi have had a similar history and origin.

Taken as a whole, the motamorphic rocks show that two or possi three periods of deposition have taken place. Two of thee may haTfrl been separate*! by a period of motamorphiNni and erosion. Vein.s werai injocteil prior to tlie deposition of tho conglomerate and its subsuquentj metamorphism. Though it is by no means certain that theip wns an; earlier period of motainurphism before the veins were such ft conclusion seems to be indicate*!. Igneous activity also occurred.., Its extent has not been but it does not seem to have bea:; connected with the formation of valuable mineral deposits. ' metamorphic rocks, with tiie exception of the conglomerates, seem be mineralized and they are believed to be the ones in which deposita< of metallic minerals are to be sought and from which the placers haft been derived.

Uesozoic And Tebtiaby Boces.

A vast area south of the Kobuk, represented within the Shungnak region by the Sheklukshuk Hills, is occupied by sedimentary rocks assigned to the Cretaceous, As htis already been stateil, these hills have not been explored witliin the mapped area by members of the Survey, and as there is no description in the literature knowledge of them has been gained only by explorations east of the Shungnak region and by tlie long-range recognition of certain characteristics elsewliere studied in more detail. From these observations it appears that many of the higher points and a laie part of the range consist of conglomerates with some sandstones, the relative proportion of the latter increasing toward the south. Those beds have been folded and faulted, but in no place has schistosity of a marked character or of extensive development been seen. Emphasis is placed upon this feature because it is impoitant in .separating these newer rocka from the sheared conglomerates of the metamorphic complex.

The pebbles composing the lower of this group have been derived from the older rocks and present a great diversity of tithology. Quartz derived from veins and lenses in tlie sclusfs forms the larger number of fragments. Tliis is probably due not so much to the abundance of the quartz in the schists as to its greater hardness.

The Shungnak Begion, Kobuk Valley. 285

which prevented rapid destruction. A laie part of the finer material found in similar rocks farther east seems to be of volcanic origin, and the rocks contain abundant plagioclase and ferromagnesian minerals. These more recent rocks occupy a part of the northern lowland and occur on the flanks of the bordering hills. These rocks in the lower part of the Ambler basin are described as follows by Mendenhall:*

Along the lower course of the Ambler outcrops were examined which consisted of a series of conglomerates, soft cross-bedded sandstones, and shales which were often carbonaceous and carried obscure remains of plant stems. Some phases of the conglomerate are made up wholly of material derived directly from the mica schists and but little sorted. White vein quartz, somewhat rounded, finishes most of the material for the pebbles, which are embedded in a matrix consisting chiefly of fine muscovite and chlorite foils. These beds make up the low hills between the lower Redstone and the Ambler and between the latter stream and the Kowak [Kobuk]. Similar beds associated with' limestone are reported by Mr. Prindle along the middle course of Shingurk Creek [Shungnak River].

Fossils have not been found in any of these rocks within the mapped area. Mendenhall,' however, on the basis of their lithology and similarity to fossiliferous beds on the lower part of the Kobuk, assigned the beds in the lower part of the Ambler to the Tertiary system. In the light of the further CAridence afforded by the surveys of 1909 and 1910 in the region south of the Kobuk, whereby a great Cretaceous area was outlined, it has seemed probable that these beds belong to the Mesozoic rather than to the younger era. According to this interpretation, the metamorphosed sediments on the south side of the Kobuk are part of the uninterrupted Cretaceous area that extends southward to the region beyond the mouth of Kuskokwim River and from Seward Peninsula on the west to Melozitna River on the east. The sediments m the northern lowland are considered to mark an infolded or infaulted block as the region of greater mountainbuilding stresses, the Baird Mountains, is approached. If, on the other hand, the younger rocks in the northern lowland are Tertiary, they may mark local basins eroded in the metamorphic and Mesozoic rocks in which later sediments have been deposited. Further investigation is needed to determine these points, but the question of age has little or no bearing upon the mineral resources.

In the region to the east igneous rocks cutting the Mesozoic and Tertiary (?) sediments have been recognized. Owing to the slight study of the later rocks in the Shungnak region no igneous rocks in place have been recorded, although they undoubtedly exist. It is highly probable that some of the unmet amorphosed basic dikes found cutting the metamorpliic rocks may have been intruded during Mesozoic and Tertiary ( ?) time, but their upper age limit could

1 Mendenball, W. C, Reconnaissance from Fort Hamlin to Kotcebue Sound, Alaska: Prof. Paper U. S. GeoL Survey No. 10, 1002, p. 41. 'Idem, p. 43.

286 MINEllAl RESOUECES OF ALASKA,

not be detcnnineti owing to the absence of late sedimentary beds of known age. Tlio ty[>ea oF igneous rock to be from analogy with the more fully studied regions are basic volcanic rocks such u flows and tuffs, majniy of andesitic eomposilion. Some granitio intrusions also have been recognized, but if the evidence afforded by the ea'*t*rn part of Seward Peninsula is applicable here most of tlia granitic iutnisions were pre-Cretaceoiis,

Veins ore practically lacking in the Mesozoic and Tertiary areas, and consequently mineral deposits requiring veins for tha derivation of tlieir valuable constituents should not bo sought for ia areas occupied exclusively by this group of rocks. The only economic resourcoa likely to occur in these areas are coal beds, but, as will fa shown in the section <leaving with the economic geology of the region (p. 304), thie n-sources are probably not sufficiently valuable ttt tempt expensive investigation.

Ttnoonsolidates Deposits.

Altliougb the hard-rock geology is of prime importance, the pli miner is must intimately interested in the unconsolidated sands an gravels in which valuable mineral tieposits may be sought. ThOTJ are many different conditions undei* which the uocoosolidal deposits were formed, and in order to understand these it is necessary to joint itiit the recent hi.story of the iv'ion, ['s|>e(.-ially as regarils the agencies, la order to do tliis the phj-biography of the region will be treated from the close of the latest period of mountain building down to the present.

Tertiary And Recent History.

At the close of tlie hiat great mountain-building period, highlands trending in general east and west had been formed in the region between the Kobuk and Noatak. Probably the Mesozoic and Tertiary (?) sediments covered this range and metamorphic rocks wore practically absent from the surface. Owing to tlie great elevation, erosion was more airtive in the high mountains than in the lower areas and consequently sooner removed the surficial covering. The drainage originally trended at right angles to the mountain range, and consequently the streams flowed north towani the ancient Noatak or south toward tlio Kobuk. The <!formation, however, by no means resulted in a single anticline but was marked by several subordinate parallel ridges with intervening syiiclines or downfaulted areas. Each of these influenced the drainage and longitudinal valleys resulted. The northern lowland is interpreted as marking one of tliese const rue tiona! low areas where the Mesozoic and Tertiary ( ?) sediments had been relatively least elevated. The

The Shungnak Region, Kobuk Valley. 287

Kobuk lowland probably marks another such area. After the dramage had been well established on tliis relief, valleys were eroded and the surface no longer corresponded to the constructional surface because the rivers were striving to cut their courses down and all the otlier processes of erosion were reducing the country to slopes appropriate to degradational processes. Thus, while the general position of the larger units of the region had been outlined by the mountain building, the present topography probably nowhere shows any vestiges of the actual surface that was produced by this process.

When the surface of the region had been carved to one somewhat remotely resembUng that of the present, either a climatic or some other change capable of producing glaciation in the highland areas took place. In this period of glaciation and in the succeeding time which extends down to the present the unconsoUdatcd deposits treated in this report were laid down. Although sands and gravels undoubtedly were deposited earlier than the period of glaciation, they have not been recognized in this region. In this report, therefore, two classes of deposits are described — first, those of glacial origin and, second, those formed after the period of glaciation, which for convenience are called stream gravels. This nomenclature is not entirely appropriate, for. the glacial deposits were in many places transported by streanLs and have water-laid rather than ice-laid characters.

Glacial Deposits.

During the period of maximum glaciation the ice centering in the highlands of the Baird Mountains on the north flowed down the existing valleys and covered the lowland areas. During the advance most of the former valley fillings of gravel were eroded and transported by the glaciers. The maximum extent of the glaciers has not been determined, owing to the lack not only of detailed studies but even of exploratory surveys over much of the region. Ice extended down the Kogoluktuk Valley, across the northern lowland, through the Cosmos Hills, and even into the Kobuk Valley. The Ambler Valley was also occupied by glaciers, at least as far as the Kobuk. Mendenhall states:

About 2 miles above the mouth of the Ambler River, on ita left bank, occurs a deposit of blue bowlder clay 25 feet in thickness. Blocks and pebbles of dark crystalline limestone, much greenstone, and relatively small amounts of conglomerate and sandstone are scattered through the clay, and these bowlders are sometimes subangular and finely striated. The rocks of the lower course of the Ambler are sandstones and conglomerates, so that the greater part of the coarser material in the clay hajB been transported at least some miles. Overlying the clay are depoflita about 100 feet in thickness of irregularly stratified yellow sands and clays without coarse material. The lower portion of this deposit at least is to be regarded as a true ground moraine, thus proving the extension of the Ambler Valley glacier to beyond this point.

1 Mendenhall, W. C, op. at., p. 48.

L 888 Mineral Re80Crce8 Of Amska, 1910.

The proof of the extension of the Kogoluktuk Valley glacier, at least as far as the Kobuk lowland, is alForded by the distinct nioraink' topography of the knobs and kettles as far south as the lower cabin. No definite proof of the amount of ice in the Kobuk Valley has ben obtained, but the effect on some of the streams indicates a body of ice of considerable extent. No frontal moraines of the glacier that occupied the Kobuk Valley have been recorded, although recessional moraines of the tributary streams are sharp and definite.

Attendant upon the advance of the ice was the blocking of proexisting drainage and the consecjuent discharge of water by unnatural channels. This continued through the period of maximum glacintion and even into the cloamg siageri, so long as free discharge was prevented. Marking these obstructions are deposits of unconsolidated material laid down behind the ice barriers in temporary* lakes or (|uit water. Nanow gorges through the hills also attest the effect of past obstruction of the drainage. Except the passes of the larger streams, such as the Kogoluktuk and possibly the Shungnak, wliich were occupied by ice, the low passes through the Cosmos Hills were probably spillways for the impounded water that was not able to pass out by its normal coui-se by way of the northern lowland, owing lo the presence of the Ambler and the other glaciers, r Not only were deposits formed in those places where obstructions caused diversion nf drainage, but even where a free discharge was permitted glacially eroded materials were <leposited beyond the front of the ice. It is at present impossible to indicate just how extensive were the modifications of the topography produced by thia enormous outwash of material. Without doubt much of the higher parts of the Kobuk and northern lowlands is formed of this group of deposits, though definite criteria are now unrecognizable, as the gravels have been partly transported by miming water. The problems connected with the glaeiid occupalitin of the region are of importance in the search for productive pincers as well as in deciphering the details which are of more purely scientific interest.

From the nature of the agency involved in gathering and transporting the materials that the glacial deposits, certain facts concerning the general chaa.ter of these deposits may be Inferred. First, owing to tlic lack of sorting action by glaciers during transportation deposits directly formed by glaciers generally consist of a heterogeneous collection of material unaffected by gravitative select tion. Second, owing to the way a glacier acquires the materials it transports and its great erosive power, the deposits it makes are, as a whole, loss weathered than those formed by rivers. The rocks are ground down or plucked bodily from the bed, so that a rock flour results from the erosion rather than a separation of the constituent rock minerals. Although the above statements apply only to depomts

The Shungnak Region, Kobuk Valley. 289

formed directly by glaciers, they require but slight modifications to fit the indirect deposits formed as outwash from the front of the ice. They are, therefore, important principles which will be referred to later in discussing the possible extension of the auriferous placers (p. 298).

Stream Gravels.

With the disappearance of glaciation the drainage modifications that had become established were continued and the temporary features due only to the ice occupation were abandoned. As a result channels marking short-hved discharges, now unoc(*upied by streams, are represented by passes such as that between Wesley and Ruby creeks or by the divide at the head of Cosmos Creek. With the development of the new drainage the streams were in some places forced to excavate part of the glacial filling of tlieir valleys; in other places glacial erosion had deepened the valleys so that stream deposition took place ; in still other places glacial modification was so that the streams flow almost on the preglacial surfaces.

In those stream valleys where glacial deposits have been formed and subsequently in part excavated, bowlders derived from rocks outside of the local drainage basin in which they now occur are found in the gravels, together with fragments which have not traveled so far. In the excavation of the valleys by the present streams the changed relation of the drainage is such that in many places the stream has not stopped its downcutting after incising its course through the unconsolidated deposits but has cut down into bedrock, forming a narrow gorge. In these places the gravels are relatively thin and are derived largely from the local rocks, although the harder and larger blocks from the older, higher gravels may occasionally be found. The incision of the present streams in narrow rocky gorges may be seen in many places where previous glacial filling is not indicated. Thus the Dahl Creek valley seems not to have received any such additional material from outside sources. This valley has a rocky trench near its base, in which the stream flows, and an older, more open valley above.

The unconsolidated deposits formed by these streams therefore present a great diversity of types. In one type the materials have been derived from basins outside the one in which they now occur, but although they have been transported a long way the sorting has been but slight. In another type, although the material is not of local origin, the earlier deposits have been so thoroughly rehandled by streams that considerable sorting has been effected. In still another type the unconsolidated deposits consist only of materials that have been derived from the basin in which they occur and transported and deposited only by streams. Each of these different types

98319*— Bull. 480—11 19

r

290 MINKRAI. RESOt'RCES OF ALASKA, 1910.

can, tliereforp, in u, measure be recognized by the size, shape, and Utholojry of its component materials. The recognition and the realization of the significance of the different characters presented by the difTerent typea of unconsolidated deposits are of importance to the placer miner, for certain fiypes of deposits are more likely to contain profitable placers than others.

The pliysical of the stream gravels witii respect to cementation by permanent frost has an important bearing on mining and prospecting, but the data available are not adequate for a tliorough analysis of the Practically all the shallow gravels are not permanently frozen. Tlie thicker deposits, especially those in whicJi there is a large amount of clay, and some of the bench gravels are probably frozen. In natural sections, sucli as occur along streams, definite evidence is not obtainable, for where the sun and air can reacli tlie material thawing takes place. Thus a section of the gravels near tlie old cabin on the Kogoluktuk showed 4 feet of uncemented and unfrozen gravels overlain by 3 feet of frozen muck, which in turn was overlain by a cover of vegetation and frost litter. The frozen layer was so covered by tlie mat of vegetation which had been undermined by the river that it was protected from the sun and air, whereas the lower gravels were not. The presence or absence of permanent frost seems to be in laie meiisiire dctfrmincd by tlie ciTet.'tiveness of siibaiirfuro dniinasie. Such drainage is best in well-rounded gravel deposits at an elevation above the streams and is poorest in those deposits containing a lai percentage of clay or silt and lying below the level of the groundwater table. The fact that the mean annual temperature as detei mined from the mean of Stoney's observations (quoted on p, 277) is less than 16° F., or 16° below tlie freezing point, makes it possible to explain permanent fr(>st in this region as due to existing climatic conditions.

Economic Geology.

History And General Stateubnt.

The gold excitement which followed the Klondike discovenee caused a geneml influx of prospectors and others into all parts of Alaska. Every little while a new camp would be reported and a rush to the new diggings would be started. During 1898 such a stampede into the Kobuk occurred. Many of these gold seekers were unequipped for tlie difficulties encountered, and as they failed to find enormously rich placers they spent the winter loafing in their shacks and when reports of the rich strikes at Nome and on the Koyukuk reached them they struck out for the new fields. An account of the experiences of one of the disappointed gold seekers on the Kobuk*

I Orlane]], Joseph, Uolit buallng la Alaska, Cblcago, D. C. Cook PubUsliliig Co., igoi.

THE SHUNGNAK BEGION, KOBUK VAUiEY. 291

gives a realistic picture of what was almost the universal condition in the region during 1898 and the early part of 1899.

With the opening of navigation in 1899 almost all the prospectors who could do so left the Kobuk and reported the region as worthless. A few prospectors have stayed with their claims and have each year taken out enough gold to Uve on and do a Uttle more prospecting, buoyed up by the hope of a rich strike. It is probable that between $50,000 and $75,000 in gold has been produced since 1898. There is an enormous region to prospect, however, and with scanty means and small outfits progress has been slow. Attempts have been made, so far unsuccessfully, to interest outside men in financing different projects.

Not only have placers attracted the attention of the prospectors, but lodes of gold, copper, and silver-lead have been located and some development work done. No production has been made and there has not been enough exploitation to demonstrate satisfactorily the character or extent of the ore bodies.

The economic conditions imposed by the geographic position of the Shungnak region have exercised and must always exercise a control that will prevent working deposits which in a milder climate and in more accessible regions could be successfully mined. It is not possible to evaluate these factors, but a brief consideration of even the single item of wages may indicate the relatively high costs that must be met.

In the Shungnak region practically no white men are working for wages, so that there are no accurate data on this subject. From the fact, however, that ordinary pick and shovel miners demand $7.50 a day and board at the Squirrel River diggings, nearly 200 miles down the river, and consequently nearer civilization, there is small reason why miners in the Shimgnak region should receive less. It is true that some of the placer miners pay natives $4 a day and board, but as a placer miner can work for only 60 to 80 days a year and must in that time gain suflScient to Uve for the other 275 days or so, $7.50 a day is by no means an excessive wage. The short season, of course, will be in part nullified if lode mines or deep placers are discovered which would give employment during the winter months. These, however, would probably not afford employment for all the miners required for open-season mining. Some decrease in living expenses is, of course, to be expected as transportation faciUties are improved. As the country raises practically no foodstuffs and probably can not, it is necessary to import everything* The long distance that such supplies must be carried, the frequent handling required, and the short season available for water transportation make it improbable that any considerable reduction can be made in this item. Consequently, as these charges must be met by wages, the apparently high cost of labor must be regarded as an almost inevitable result of the isolated position of the region.

j92 MINERAL RESOUECES OF AUASKA, IBIO.

GOLD FIJICEBS. From the foregoing statciiK'nts roncprning th number of miners in I the Shungnak region, it is evitkint that placer mining is not came<! L on extensively and tiie production from the region is but little more [than enough to pay wages to the few men employed. Tlic main placer developments are on the streams heading in or flowing tlirough the Cosmos Hills, namely, Dahl Creek, Shungnak River, and Riley Creek, a tributary of Kogoluktuk River, Eaeh of these will in turn be described and the general placer resources of the ropion noted.

f DAHL CREEK FLACERa,

Dulil Creek is a stream 7 to 8 niilea long, the lower 3 miles or so of its cijurao being through the Kobuk lowland, the middle 2 or 3 miles in a narrow rocky gorge, and the upper mile or two in a rather open valley. The placers that have been worked are located near the aoutheni face of the Cosmos Hills and in the central part of the valley, where the junction of three small side streams with Dahl Creek has made a small flat. During the time that the Survey party was in the region no work was in progress on any of these claims, but mining had been carried on earUer in the season at both places and had been in progress for several years in the past.

The bedrock under the unconsolidated deposits here is black slate and schist mth numerous small vf'ms of quartz niid in places some sulphide mineralization. Tlie bedrock breaks into rectangular blocks of small size and the joint faces are often iron stained. The dominant strike is across the creek and thus the rocks make natural riffles for catching the gold, Tlie slope of the bedrock surface is rather low, 80 that some diiliculty is experienced in disposing of the taihngs from mining. Near the lower group of claims scliistose conglomerate outcrops but does not form bedrock under the productive placers. Limestone occurs near the placer ground in the middle part of Dahl Creek, but although float from this rock is found in the gravels it does not come down as far as the creek and does not form any of the surface on which gravel accumulation took place. Igneous rocks of a dense texture and greenish glassy color were noted u])stream from the placers, but though these rocks have furnished many of the bowlders in the placer deposits they do not seem to have been connected with the mineralization and did not contribute valuable minerals to the placers.

Only the creek gravels have been mined on Dahl Creek. These average about 4 feet deep. In places they are only a foot or so thick but in others they are as much as 8 feet. Holes sunk on some of the low benches on either side of the stream have shown unconsohdated deposits 15 feet thick. Practically all the stream gravels are unfrozen, except for seasonal frost, hut some of the low benches that have been prospected are reported to be permanently frozen.

The Shxtkonak Rechon, Kobuk Valley. 293

The gravek in the productive placers are typical creek gravels, consisting of well-rounded pebbles with only a small amount of muck. Large somewhat angular bowlders, most of which are of local derivation, are numerous in the gravels and cause a good deal of trouble in the mining operations. One of these large bowlders a short distance below the placers, near the southern face of the Cosmos Hills, measiired 14 feet in length. It is made of the sheared conglomerate and has not been transported far. Many smaller bowlders occur directly in the auriferous gravels, however, and it is necessary to blast them out of the way.

The pay streaks differ in no essential respect from the overbiuden. They are usually from 1 to 2 feet in thickness and practically all the values lie in and on bedrock. The distribution of the auriferous gravelsis very irregular, and it has been impossible to trace successfully any continuous pay streak. The values occur in pockets which when exhausted give no clue as to their relation to other rich spots. Such a distribution seems to indicate that values were either laid down more or less evenly and then dispersed by a change in the discharge of the creek, or else that the gold was originally deposited by a stream having strong variations in transporting abihty.

Owing to the irregular distribution of the gold, statements of the value per cubic yard are of little significance. When a rich spot is found, several hundred dollars may be taken out in a few days, but at other times only a dollar or so a day can be made. Figures for the total production are also unsatisfactory, but they give a more accurate estimate of the value of the ground. The returns are not complete and probably exaggerate the amount of gold recovered, but they are an index of the size and present importance of the creek. According to the returns from tlie miners, in no year has Dalil Creek produced more than $10,000, and probably half this amount is nearer a correct estimate for tlie average production during the last six years. If this assiunption is correct, not over $30,000 lias been taken from tliis creek since its discovery.

Only a small amount of Dalil Creek gold was studied, so that a fuU description can not be given. The gold examined from the upstream group of placers was of a reddish to brass-yellow color. The pieces were small and some were distinctly spongy and had fairly sharp outlines, as if they had not been transported far from their place of origin. Some wire gold was also seen, but it was rare. Nuggets of considerable size have also been found in this part of Dahl Creek. One of these was seen which had a gold content worth about $65. It was a fairly well worn piece and had a considerable amount of greasy-looking milky quartz attached. Assays are reported to have shown gold value of about $16.20 an ounce.

Among the concentrates from the Dahl Creek placers magnetite is the most abimdant mineral. There is also a

294 Mineual Eesources Of Alaska, 1016.

chromito, some of the pieces being a foot or so in diameter. Gamete are almost entirely absent. The ocfiurence of native silver in the eoncentratea has been reported and pieces nearly an inch in diameter have been examined. The silver seems to be particularly free from admixture with other metallic minerals such as copper or lead; a small amount of cadmium, however, was recognized bj' blowjiipe examination. No evidence was procured as to the bedrock source of the silver.

Mining is done by pick and sliovel methods ainl the gold is won by passing the (jjavels through sluice boxes of whipsawod lumber. Owing to the high transportation cJiargos, machinery would be expensive to install, and owing to the character of the gravels and their tenor, few mechanical devices could be successfully operated. Short J ditches provide the necessary head for sluicing, and there is almost I always a sufficient water supply to meet the demand.

From the physical features of the gold and the distribution and other characters of the aiiriferous alluvium, it seems probable that the gold has been derived from a source within the Dahl Creek basin. especially from the areas occupied by the blatrk slates and schists. It is believed that the source of the mineralization is the quartz veina which are so abundant in this formation.

Some prospect holes have been sunk near Dahl Creek close to the southern front of (he Cosmos Hills or the northern margin of the Kobuk lowland. The returns, however, have been insufficieDt to warrant development and the holes have been allowed to cave, so that it was impossible to examine a section of the gravels. It was reported by prospectors that the bedrock surface slopes southward at a high angle below the lower cabins, so that shafts even 40 feet deep failed to reach bedrock. In this lower part of Dahl Creek the stream is flowing through the unconsolidated deposits of the Kobuk lowland. The absence of any shallow placers in this part of its course seems to indicate that the upper parts of the gravels of the lowland area do not contain sufHcient gold to form economic deposits where subjected to tlie sorting of such streams as Dahl Creek.

Kogoluktuk River.

Sparsely disseminated colors of gold have been reported from manj parts of tile Kogoluktuk basin, but the only stream on which placers have been mined is Kiley Creek. Tins is a tributary from the west, heading against the Dahl Creek divide and flowing first north and then east to join the Kogoluktuk. Placer ground has been mined in a desultory way by parties of one to three men on the headwaters of this stream since 1908. Mining was in progress here when the region was visited by members of the Survey in the early part of August, 1910, but soon afterward was abandoned for the e

The Shungnak Region, Kobuk Valley. 295

The placers occur in a region of black slates, limestones, and a few intrusive igneous rocks. The bedrock is similar to that of the placers on Dahl Creek except that limestones are much more numerous. Evidences of deformation and dislocation are pronounced and the stratigraphic succession of the rocks has not been determined. Quartz veins are particularly numerous in the black slates that form the bedrock under the ground that has been worked and are believed to be closely associated with the formation of the productive placers.

In the placers typical stream gravels are practically lacking. Sections show angular slide and slightly worn unconsolidated deposits of local origin in which are irregularly distributed bowlders from outside basins. Most of these foreign bowlders are of large size and are mainly igneous rocks belonging to the group of greenstones and associated rocks. They are generally well worn and probably have been brought into their present position by the combined action of ice and water during the closing stages of the glaciation of the northern lowland. Although these greenstone bowlders are found in the placers they are in no way connected with the origin of the gold, and their distribution, except as marking former glacio-fluviatUe conditions, is of no economic significance.

The gold occurs mainly in the crevices of the bedrock and in the angular unconsolidated material lying on top of the bedrock. In the part of the deposit that is mined large bowlders are less numerous than in the upper 2 or 3 feet of the deposit, but there are many bowlders even in the pay streak. The whole character of the material in which the gold is found is more like that of residual placers than that of ordinary creek placers.

The slight amount of transportation that the auriferous material has undergone is also indicated by the shape and quality of the gold. Practically all the pieces examined were sharp and angular and many had small particles of quartz attached. No large nuggets have been reported from these claims. Pieces worth as much as 50 cents were seen, and a few worth $2 to $3 were reported. The gold is bright and in an average sample the pieces were worth from onetenth cent to 2 cents each. The individual particles are spongy and consequently appear, to one not used to the run of placer gold, to be worth much more than is actually the case. The precise assay value of the gold was not learned, but it was understood to be about $16.25 an ounce.

Accurate estimates as to the total production are not available, but from the amount of ground that has been mined during the last three years and its reported tenor it is beUeved that not much more than a thousand dollars a year in gold has been won.

Mining costs are high and the Riley Creek placers are unfavorably situated for economic development. The two greatest obstacles to

296 Mineiul Eesouhces Of Alaska, 1010.

cheap milling ure the nlwenrp (if a sufiU-ient Wftti?r supply the preaof luip> ixiwldcrs, The Intt'r tniublc, however, is not so scriouit- OH the lack of water, for fi'W of the [wwliltra ure so lame thiit Lhcy t'tia not be ndled buck by hand or got rid of by undermining. Practically thi) only wBt(<r itvailabli* is dmTcd from the inciting snow on the northward-faring ship of the divide between Paid and Kiley creekH. Furrows parallel witb tlie contour have been dug on the hill slope ta collect the surface and shallow soepage water formed fi-om the melting snow bunks. From theso furrows the water is led down tlie hilUide and impounded behind a sod dam. Thenc it is led by ix short ditch and hydraulic hose to the sluice Iwxes. So slow is the collection of water tliafr under fiivoriiblc conditions it takes about ;ji hours lu; collect enough for 1 i hours' sluicing. No waU-r, of course, can 14 spared for groundsluicing. Even shoveling into the sluice boitm caiL only be done for four or five periods n. diiy. During wet weather ti reser\-oir fills up more rapidly and so relatively longer periods ofsluicing lire possible.

After the period of nluiciug and while the re3er\'oir is refilling tJi niinets clean away the large bowlders and get everything in rciulineM for the next tunc that the water has accumulated. The large bowl ders ore not cleaned hut are simply rolled upon the part of the claim already worked uut. In order use ths water effectively tlie aluics boxes are miidc mdy iibout hidf the ordinary width and were formerly set on a [litch 1 inch in 1 2 inches. Subse(|uently, however, in order like ciire of llii' (.tilings and lessen the height to which the gravels were slmvele.l, ,i pitrli of ] to 15 whs adopted.

The Riley Creek iiljieci-s Inivo been worked seem to derive their gold content from llie rucks e\])osed in the immediate vicinity. They arc ,sii .situiited that they hiive no adequate water supply and bowlders are so nnrnenuis that tlie placer can be developed only at great ex|)cnse. Furtlier ilowiistreiim, where the water supply might more nearly nigel the di'mands, thicker overlying <leposits and birge bowlders ure pndmbly ]ire,sent. The absence of especially effective sorting in this part of the basin suggests tiiat placers will be of distinctly local importance. The whole Kogiihikink basin, so far as indicated hy the conditions on Kiley Creek, scene to promise only loealixiMl placers of irregular distribution, workable as pockets rather tlian tis extensive ileposits.

SnUXGXAK KIVF.R.

Placer mining nn Shungnak River has been carried on for a mile or so below the nari-ow canyon in which this stream traverses the Cosmos Hills. Work has bcen in progress here during the open season almost uninterruptedly since 1898. Only two or three parties of three or four men each liave attempted mining during any one year, and in 1910 only one placer camp of one wliite man and two

The Shunonak Region, Kobuk Valley. 297

or three natives was in operation. The use of native labor is an interesting experiment, and although it is reported that white men can do more work the wages paid the natives (about $4 a day and board) are so much lower that the difference in efficiency is compensated for.

Bedrock in the productive part of the river is mainly black slate and schist, but other sedimentary and igneous rocks occur at no considerable distance from the placers. Limestones occur near the head or northern end of the canyon but are not closely associated with the deposits of auriferous alluvium. The igneous rocks in proximity to the placer mines are composed mainly of serpentine, are of a darkgreen color, and contain scattered particles of magnetite. These rocks have been sometimes mistaken for jade, and it is probably owing to this error that the whites have reported the name Shungnak to mean jade in the native language.

Most of the mining has been done near the southern face of the Cosmos Hills, where small flats permit turning the stream aside by wing dams. The gravels mined are generally shallow. The upper 2 feet or so is stripped off and the lower part only is put through the sluice boxes. The overburden is made up of typical river gravels with some large bowlders irregularly distributed throughout. It is not known whether the valley of Shungnak River through the Cosmos Hills was at one time occupied by ice, but it is certain that glacially eroded and transported bowlders have been brought in by glacio-fluviatile action and form part of the reworked material of the unconsolidated deposits.

The auriferous gravels are rather irregularly distributed and therefore mining has been in the nature of pocket hunting in those places where the water could be handled. The gravels are unfrozen, and in a measure this is a disadvantage, as it allows much water to seep into the pits. During high water the miners are sometimes driven out of the workings. The values are found in the lower part of tlie unconsolidated deposits and in the crevices of the bedrock, especially where the bedrock is black slate.

The larger part of the gold found in the placers of the Shungnak is in small pieces worth from one-half cent to 3 cents, but nuggets worth about $40 have been found, although they are by no means numerous. The gold is of a reddish color, and although not rusty it is not bright and shiny but has a dead luster. Its assay value is reported to be $16.70 an ounce. The form of the gold is very characteristic and is distinct from that of the gold from any other part of the Shungnak region, the Uttle pieces being like shot flattened with a hammer.

Among the concentrates collected with the gold magnetite is by far the most abundant mineral. This is probably derived from the basic intrusive dikes which cut the metamorpbic locJsa. CiwcYkfcXi ot

298 Minebai Resoubces Of Alaska, I&Io.

so-called ruby, is almost entirely absent from tlie gravels. Small nuggets of copper ami also of silver are soiiietinies found in the sluice boxes. Some of the silver nuggets are nearly an inch in diameter and contain but very small amounts of other metals as impurities. No clue as to tho origin of the silver was obtained, but the nuggets were ])robably derived from the zone of rock impregnated with copper sulphide near the limestone-schist contact, an example of which is described iu more detail on page 300-302.

Statistics of the production from the Shungnak River placers have not been kept, and estimates prepared by interested ]>arties are not rehable. It is improbable that the annual production amounts to mora than a few thousand dollars in gold, and a Uberal figure for tii total production from tliis river would not be more than $50,000.

Scmmaky.

The amount of development and thp estimated production iudicottt that the gold jilacers discovered are not extensive or liighly profitablsj The gold seems in general to be of local origin and tliis necessarily curtails the area in which productive placers may be sought to ' Cosmos Hills and the Baird Mountains. The general effect of tht glaciation of the region lias been to disperse auriferous depouta that might previously- have been formed and so destroy rather than produce commercially vuhialilc jdaccrs. Where gliiciiil ami nttL-nilunt gIacio-flu\'iatilc action <lid not entirely remove the auriferous deposits it undoubtedly- partly eroded and tnmsported them, and this fact ]robably accounts for ii good deal of the irregularity of distribution. The disadvantageous economic situation due to geographic and trade conditions docs not need to be discussed at length here, but these conditions arc necessarily deterrent factors in the development of these ]laccrs.

Lode Deposits Of Metallic Minerals.

At the present time no lodes liave been developed to a producing stage in the region antl there are ver3' few jtlaccs where even prospecting has amounted to much more than the annual assessment work stipulated by law. As is usual, much of the trouble has been due to the prospectors overburdening themselves with more claims than they could handle, so that their efforts have not been concentrated on any particular |)!acc. Conscquentlj-, so far as affording information about the lodes is concerned the prospecting has been largely valueless, and one examining the region is forced to rely mainly on natural exposures of the possible lode deposits. TTiere are indications of mineralization at many places, but the general inaccessibihty of the region and the high valuation set on many of the prospects do not invite the investment of outside capital. Without

The Shungnak Region, Kobuk Valley. 299

abundant funds the developments are hampered and many of those attempted are ill directed.

Golu Lodes.

On the divide between Dahl and Riley creeks, as has already been noted, there are numerous veins in the black slates and schists. Most of these veins are small stringers, but some lenses 18 inches to 2 feet in width were noted. In one vein in particular on this divide specks of gold are reported in the quartz and a shallow prospect hole had been dug. The broken quartz from this hole had been panned and numerous small particles of gold are said to have been obtained. On the northern slopes of this ridge and continuing as far as the placers on Riley Creek there is heavy quartz float all over the surface. In many pieces of the float fine gold is visible and some containing several dollars' worth of gold are reported to have been found. The auriferous quartz from this place is mostly of a dense texture and a greasy white color. Sulphides are almost entirely absent. In this respect the veins resemble those of Seward Peninsula. In places the quartz is iron stained, but the discoloration is not present everywhere or in considerable amounts. The quartz in places shows indications of a comb structure and does not seem to have been recrystallized or badly smashed. On account of these characters it is believed that the veins from which this quartz was derived belong to a series formed later than the maximum period of regional metamorphism. This interpretation is further supported by the greater continuity of these veins as compared with those in the oldest schists of Seward Peninsula. It is beUeved that these quartz veins are intimately connected with the local placers on Riley Creek and that they are the sources from which the placer gold was derived.

An attempt to interest outside people in developing this gold quartz has so far proved unsuccessful. From the character of the exposures of quartz veins in the immediate vicinity it appears that the treatment of the vein material would require the handUng and miUing of a large amount of the coimtry rock as well, and this would necessarily reduce the gold tenor. The question whether these veins can be worked is answerable only by careful and extensive sampUng of the kind of material that must be mined and milled if the project is developed commercially. It is evident that picked specimens are absolutely worthless in arriving at the valuation, and samples of the vein material alone are likewise misleading.

There are many other places where veins similar to those at the head of Dahl Creek have been seen, and it is by no means improbable that they, too, carry some free gold, although in the hurried examination it escaped detection. These veins are more nimierous in the areas occupied by the black slates, especially near the base of the limestones. This distribution appears to be

300 Mineral Besoubces Of Alaska. Imo.

jiliysioal features of the 8lat.es, biit the deposition of gold may tinTt Ik'011 due to chemical reactions induced by the presence of carbonaceouB material tlimughout these rocks.

COPPER PllOSPECTB.

At two places at.t* htivo been made to prospect copper leads, but at neither place have the explorations been sufTiciont to deter mine the extent or other geolopc relations of the ore. Orie at ihvsci projects is located on the west aide of Ruby Creek shout 6 miles from the junction of that stream with Shungnak River. Tfae oilier lies west of the left fork of Ruby Creek, near the head of Cosmos Creek. A low limratone hill, locally known as Aurora Mountain, is the center around which the claims at the latter locality are gmuped and this name will therefore be used to designate that locality,

leads on Ruby Creek have been known for many, yours and were critically examined in 1906 by experts in pnvata employ to <determine their commercial value. Conditions at* that; time prevented the purchase of the properties, and only a smati' amount of work has beon done recently. Owing to the lenglii of time that has elapsed since active work was in progress, many the pita and open cuts have caved and filled to such an extent that they afford poor opportimity for examining tlie deposits and adjacent nicks. In this part of the Ruby t'reek valley on the lower slopes there is a heavy covering of talus and vegetation, so that without pits and other sections many important facts are indeterminable.

Mineralization on Ruby Creek appears to be confined to a breccintcd zone or zones in the limestones. Sulphides have been deposited ill the open spaces thus formed and the ore-bearing solutions have the limestone along the manj'' cracks and crevices and in ]>art replaced it. There is some hrecciated dolomite at the niirif, and it also has been replaced and intersected by sulphides. The sulphides of economic importance are mainly bomite and chalcopyrite, but galena and pyrite were also noted. In the sur- (icial part of the built the blue and the green copper carbonates are common. Timtmite, derived fr()m the weathering of the pyrite, in several places forms a gossan, or "iron hat," several feet tliick over the sulphide-impregnated limestone. It is reported that the weathered nuiterial when panned yields colors of gold. Average pans of the gossan from an open cut above the miun workings are said to give from 1 to 3 cents in gold. Assays are said to have yielded as much as 1 1 per cent of copper, but no details were obtained as to the manner in wliich the samples were taken.

The main developments on the northernmost property consist of an adit and two open cuts. The mouth of the adit is only a few feet above the high-water level of the creek. The tunnel has been

THA SHUNGNAK region, KOBUK VAUiEY. 301

driven about 40 feet through a much slickensided and fractured limestone in places showing mineralization. Two short drifts, totaling only about 30 feet in length, followed especially strong indications of miaeralization but evidently soon passed out of rich ore. The walls stand fairly well, but caving of the surface has so blocked the mouth of the adit that there is 12 to 18 inches of water standing on the track. A boiler was brought in from the Kobuk by way of the low pass at the head of Wesley Creek by a team of 70 dogs. When work was started a homemade mine car was used to tram the broken rock away from the working face, but a new automatic dumping car has since been installed. Wooden rails are, however, still in use. Natives have been employed as muckers and for the simpler mining operations and are said to have given satisfaction.

On the hill at an elevation of about 150 feet above the adit an open cut about 30 feet long and 10 feet or so wide had stripped the surface and had cut into the bedrock to a depth of 5 to 7 feet. Most of tliis pit was covered with caved surficial material so that little could be seen. The mineralization seemed to be essentially the same as that exposed in the adit. In the open cut although the bedrock is limestone it differs in some respects from that exposed in the tunnel, for none of the dolomitic phase was recognized and in places it seemed to be darker and suggested correlation with a luther horizon. However, there has been so much dislocation that the structure was not determinable and in the absence of fossils the above suggestion is to be regarded as little better than a guess.

At about the same elevation above Ruby Creek as the adit already described and 200 to 300 yards southeast of the open cut on the hill another open cut about 30 feet long has uncovered a zone of mineralization. The mode of occurrence is essentially the same as at the two other places, but only the upper weathered portion has been exposed. Copper minerals are less abundant here, but there is more limonite. Sulphides were but sparingly seen; the iron occurred mainly as oxide and the copper mainly as carbonate. It is reported that samples of the ore from this cut have a higher accessory gold content then that from either of the two other places.

About 3 miles west of the Ruby Creek copper leads is Aurora Mountain. The geologic structure at this place is essentially synclinal; brecciated and deformed Umestone forming the top of the hill hes above a series of dark slates and scliists that form the lower slopes. Near the contact between the two rock groups but occurring almost invariably within the limestone are indications of sulphide mineralization. The surface of the hill is so covered with frost-riven talus of limestone that except in artificial cuts the rocks are not exposed in place. Here and there copper carbonate float is found in considerable abundance.

302 Minekal Resouhces Of Aiaska, 110.

Developments on Aumrn Mountain consist mainly in finding placLis whoro copper float is particularly abundant and then digging a hole tlirough Uie overljTng mantle of detritus. The only prospecting of this sort tJiat has been carried to any considerable extent is on the northeastern slope of the hill about 300 feet above the contact of tlie iiuiestone and schists. Exploration at this place at first consisted in sinking a shaft on the uphill side of a particularly conspicuous area of carbonate float. At the time tliis place was visited in 1910 the shaft wa.s partly filled with water and its walls were so covered with ice that tliey could not be examined. It was reported that the shaft was about 22 feet deep and intersected a fairly promising copper lead about midway between the surface and tile bottom. The bottom of the shaft is also said to have shown some good ore. Samples from the lower part of the shaft show bomite and chalcopyrite as well as carbonates.

Owing to the difficulty of mining the shaft was abandoned and & crosscut at about 2-50 feet lower elevation was commenced to connect with the deepened shaft. This adit is now in about 30 feet, and it will he necessary to extend it over 250 feet to reacii a point directly underneath the shaft. Throughout its length the adit is in barren brecciated limestone, in few places showing any mineralization. Slickensiding is evident at many places, but although amount of throw wiia not dclcruiined it probably was nfit vciy great, as dilTcrent rocks were not brought into juxtaposition. In spite of the brecciation and faulting the rock stands well, and it has been necessary to timber only the entrance to the adit where it passes through the surface detritus.

Analyses by Thomas Price & Co.' of picked specimens of the bornite are reported to show 0.04 ounce of gold per ton, worth about 82 cents, and 1.4 ounces of silver per ton, worth about 91 cents, in addition to tlie copper content. Assays by the same analysts of chalcopyrite from Aurora Mountain yielded 0.01 ounce of gold per ton, worth about 20 cents, and a trace of silver in addition to the copper. Neither at Ruby Creek nor at Aurora Mountain, however, does the sulphide mineralization seem to have produced auriferous placers. In Ruby Creek colors of gold have been found, but at Aurora Mountain no placer gold has been reported in the stream gravels.

Although the Ruby Creek and Aurora Mountam localities are the only ones where prospecting has been carried on, there is probably similar mineralization at many other places. In fact, mineralization near the contact of certain of the hmestones and schists has been recognized all the way from Seward Peninsula to this region. So far prospecting has failed to show that any of these deposits either in Seward Peninsula or in the Kobuk region are workable. ' LlOf d, L., uapublUhed letter.

The 8Hungnak Region, Kobuk Valley. 303

Until the mode of origin and the general characters of ore bodies of this type are fully understood it seems unwise to do much dead, work, such as running long crosscuts to intersect a possible ore body in depth. Even after a considerable body of ore has been disclosed a careful scrutiny of the costs of mining in this remote and rather inaccessible region should be made before expensive permanent mining machinery is installed. Although these facts should not discourage intelligent prospecting, they should serve as a warning that the search is likely to be expensive, as the cost of proliminar}' investigation will be high.

Other Metallic Resources.

Galena has been found in small quantities associated with the copper sulpliides at both Ruby Creek and Aurora Mountain. A small amount of vein quartz and some brecciated and recrystallized dolomite with galena was seen near the high hill west of Wesley Creek. A shallow prospect hole has been sunk on this stringer, but so far the indications are not at all promising.

At many places magnetite in masses as much as a hundred pounds or so in weight has been found on the surface, especially near the limestone-schist contacts. Float of this sort is particularly abundant on the slopes of the sharp conical hill locally knowTi as Iron Mountain, east of the pass between Cosmos Creek and the left fork of Ruby Creek. Specimens from this place show a nearly pure magnetite with here and there drusy cavities lined with small octahedral crystals of this mineral. As the magnetite has not been seen in place, speculation as to its origin is hardly warranted. There are no near-by igneous rocks, so it seems improbable that these bodies are due to contactmetamorphic effects. Owing to the occurrence of limonite and hematite bodies in similar limestones in the Solomon region of Seward Peninsula a tentative suggestion Is that the magnetite of the Shungnak region may have been formed by the metamorphism of similar iron oxides which were laid down either contemporaneously with the inclosing limestones or earlier than the great period of dynamic metamorphism. The magnetite shows no signs of having been sheared, so it must have been either entirely recrystallized or deposited subsequent to the period of regional deformation.

Whatever theor} of origin of these ores proves to be the true explanation probably matters little, for tlie deposits so far as known have but slight economic value. The high operating costs coupled with the absence of large ore bodies will necessarily deter capital from undertaking their development.

DEPOSITS OF NONHETAUilC MINEBALS.

The geographic isolation of the Shungnak region has prevented will probably for a long time prevent the development of any of

804 Minrrai, Eebources Of Ajuasea, 1910.

tliL' nomnetollic: rtfsources t-xcept such ns can be consumed near iho plare where they ar produced. Of these resources the water supply is llie OTio most necessary for local uses, but so far it haa been little dfivplopfid. If mining of gold and other metallic minerals increasea in llie region, this source of power mnj become of great value. At the present time, however, placer mining is conducted on so small a scale that either a siifficient water supply can be secured by short ditches or the claims can not afforil to pay for an adequate supply.

Ill the Mesozoic and Tertiary ( 'i) areas of the Sheklukshuk Hills and of the northern lowland some coal has been reported. The chances of deposits of sufficient value to be used at places murt than u short distance from the veins seem to poor. This opinion is based on the fact that on the Kobuk a coal bed belonging lA tlus same series of rocks, exposed on the banks of the river and situated almost 200 miles nearer ocean transportation, has notproved commercially valuable, although attempts to mine it hars. been made at intervals ever smce 18S6. Although probably none ol* the coals that may be found in the Shungiiak region will support extensive industry, their value for local consumption may be su& cient to warrant the search for coal in the areas of Mesozoic and' Tertiary( ?) rocks near productive metal mine.

Some attempts have been made to mine asbestos. This minora! is found in morp or Ifss close iissnciiition wifli the greenwlono irilnisives. Several holes have been in ledges of this rock on the east side of Dald Creek above the upper placer mines, and samples of the asbestos have been submitted to manufacturers. It is reported, however, that tJie asbestos although of good color has slight tenacity, so it Is not suitable for making high-grade articles and therefore commands a low price. For ordinary purposes this jisbestos is well suited, but tiie small amount paid for this grade is not sufficient to pay the transportation chaises. Furthermore, the amount so far knoll is small, and it would therefore be expensive to mine.

In almost all the streams of the SImngnak region north of the Kobuk bowlders of a hard green, slightly translucent rock are plentiful. These are commonly called jade, but this determination is probably incorrect. A complete examination has not been made, but some pieces are imdoubtedly serpentine, others are green quartzite, and still others are probably nephrite. The last-named mineral is closely akin to jadeite but Is an ampliibole instead of a pyroxene and Is not of gem quality. It is doubtful whether any jade of value occurs in this region, for of all the material from the Kobuk so far examined by the experts at the National Museum none was jade. Even in the so-called jade no pieces of gem quality were seen. The imperfections are due to rock cleavage and to the presence of a metallic iron mineral, probably magnetite. The cleavage causes the

The 8Hungnak Region, Kobuk Valley. 305

mineral to split into thin layers, wliich makes cutting difficult and the surface flake off; the magnetite spoils the translucency and gives the stone a spotted appearance.

In concluding this report on the economic geology of the Shungnak ron certain generalizations already expressed or implied seem of sufficient importance to bear repetition. At the present time the developments are on a small scale and their production is almost negligible. Prospecting has been inadequate to test the region thoroughly, but it has been commensurate with the number of men and capital available. The future of the region seems to depend more upon the auriferous deposits than upon the nonmetallic resources or the lodes of the base metals. Therefore unless placers of a type different from those now worked are found in the gravels of the lowland areas there is only a small field for prospecting and this is limited mainly to the Cosmos Hills. The geograpliic conditions affecting the economic future of the Shungnak region will continue to impose limitations that only especially rich deposits will be able to overcome. For these reasons, although a small and perhaps increasing production may be expected, the region as a whole does not seem to hold forth any great promise of large enterprises. It should be stated, however, that although the region may not rival the better-known camps it appears from the observations made in 1910 to have resources capable of supporting a small community, so that some prospectors and miners will find a profitable field for exploration.

98319°— BuU. 480—11 20

The Squirrel River Pucers.

By PniLip S. Smith.

Introduction.

Diirinfi the later part of the o|({'n season of 1909 a new nf productive gold placers was discovered in the Kobuk mining district, Alaska. Although this oamp is still in the early stages of development and although the production so far has been small, the promIs held out to miners in this little-exploited field is attracting attntioD, The following observations were made in August, 1910, during a few days' visit to the new camp and are necessarily incomplete.

B RODTE8 AND ACCE8HIBIUTY OF ItEOION.

The productive area so far discovered is in the lower part of the Squirrel River baain. J

The general po-silioii of this region with respect to better-known parts of northwestern Alaska is shown by figure 19 (p. 272), A largerscale map of the eastern part of this field forms Plate XIII. This map is based mainly on surveys bj' Reaburn in 1901 ' and reports by prospectors, most notably John Tyapay, one of the original locators of >- Creek, togetlior with such notes as were collected during the writer's recent visit. But small cartographic precision can be claimed for tliis map, though tlie representation of the relation of the streams to one another is approximately correct. In such an undescribed region even a sketch map of this sort maj' be of service to the prospector and will certainly make the local nomenclature used in this paper much more easily understood.

Squirrel River is tributary to the Kobuk from the north, about 42 miles in an air line from Hotham Inlet or 60 miles from the nearest coast settlement, Kotzebuc. Owing, however, to the circuitoua course of the Kobuk and tlie approach to its mouth the distance to be traveled is 28 miles from Kotzebue to the mouth of the Kobuk and 68 miles from this point to Squirrel River, or a total of nearly 100 miles from Kotzebue. In the winter, when the region is ice-

1 MvnJfiihaU, W. C. llnwnDalssance Iram Fort llBmlln to Kotubue SouiicI, Alaska: Prof. Paper U. S,

The Squirrel Biveb Placebs. . 807

bound, access is much easier than during the summer, when countless sloughs and 'niggerhead' tundra preclude overland travel.

Kotzebue is the seaport of the entire Kobuk region and is normally the home of a missionary and family, three white traders, a few boatmen and mechanics, and a small settlement of natives. After the break-up in the spring, however, missionaries, school-teachers, and prospectors, together with a great number of natives from all the neighboring rivers, congregate for trading and fishing in preparation for the coming winter, so that during July and August there are 600 to 700 people living in the town, which then stretches for more than 3 miles along the coast. A mail-boat service from Nome to this place is maintained every 10 days during the summer. The boats, however, are only 30 to 50 ton schooners with auxiliary gasoline power, and the passenger accommodations are cramped and inadequate, although the food is good. The trip from Nome by one of these boats takes about three days, as stops are made at many way points, and tlie charges in 1910 were $25 apiece for passengers and about $20 a ton for freight. It is not possible to use boats drawing more than 5 to 6 feet of water, as the channel up to Kotzebue is narrow, crooked, and shallow. Some larger boats from Seattle enter Kotzebue Sound, but they can not approach nearer than Cape Blossom, wliicli is 10 to 12 miles south of the town of Kotzebue. In the winter a mail service by dog sledge once a month is maintained from Nome overland to Candle and Kiwalik and thence along the coast and on the sea ice to Kotzebue.

In the summer freight and passengers from Kotzebue for the Squirrel River diggings are transshipped to small gasoline launches or scows which draw only 2 feet of water or less and after crossing Ilotham Inlet go up the Kobuk as far as the junction of Kobuk and Squirrel rivers. Tliis trip takes from one to two days, depending on the stage of water and the load, and the charges are $15 apiece for passengers and about $15 a ton for freight. A short distance above the junction of the two streams is a small settlement formerly called Squirrel City but subsequently renamed Kiana. Here are a score or so of log cabins, a store and restaurant, and many native families engaged in fishing. It was understood that before the freeze-up two more stores were to be opened at Kiana and the recording office for the Noatak-Kobuk precinct was to be established at this place. The houses cling to the steeply incised valley walls, and there is but little drained flat land available on wliich the town can develop. Timber is scanty in the immediate neighborhood but can be floated down the Kobuk from points farther upstream where it is more abundant. Logs suitable for cabins were sold for a dollar apiece delivered in the water alongside the town. Water for domestic use is taken from Squirrel Kiver and is likely to be contaminated

SOS - MINEIiAI. RESOURCBS OP AL.A&KA, 1910.

unless carl is exervi'd, no olhpr supply is availabk*. Prices for sUjilu tirtU'lca in 1910 were Iiigh in Kiuna owing to the coat of pftling supplies inti) tJie tiic loss attendant upon the many reliandtings, and the lack of active compotilion.

Tu continue tlie journey lu the plarer dings the next stage is by small boat from Kiana up Squirrel River. The country betwei'ii the river and the hits h wet and swampy, and though during high water light-draft launches can go for many miles above the settlement, ordinarily the trip can be best made by dory or other boat drawing not over 6 or S incht-s of water. By tliis method Squirrel River ia ascended for about 7 miles to a slough which makes off toward the north and east and which at the lime of the visit by the Survey geologist was so sJiallow near its junction wilh Squirrel River tliat the dory, containing only about 500 pounds of freight, had to be partly unloaded and hauled over the shallow riffles by men Uftitr on each side of the boat. Finally (he slough enters a nearly round lake iwlween one-fourth and one-half mile in diameter, which is the nearest point by water to the placer diggings. The freight ehargm from Kiana to this place are 2 cents a pound. Several tents had been put up on the shores of the lake by some of the miners for their own accommodations, so that a traveler coidd obtain shelter. From the lake it is about 7 miles over rolling slopes to the placers that are M being worked, but midwiiy there is n rood h'.'use where bojird Hiid lodging can be hod at a dollar a meal or bed. A freighter with two hoi-ses, employed mainly by one of the mining companies, makes more or less regular trips from the hike to the dings. The trail is over veiy soft gi-onnd, where even the foot traveler is most of the time half-leg deep in muck and water, bnt the freighter is able to carry loads of 700 to 1 ,(100 pounds in a two-horse wagon at a rate of ahiiut a cent a mile a poiuul. Altlumgli horses and wagons are used on tlus trail, one inexperienced in the country should be warned that onlj' a thoroughly competent driver with horses long accustomed to the peculiar and tretichenms footing ran successfully make the trip. Furthermore, the cost of keeping horses in the region is great, for (hey must be fed oafs, which cost from .5100 to $150 a ton.

C'Limate.

In addition to the difficulty of reaching the region in the summer time and the high cost of transportation, the shortness of the open season exercises a marked influence on the economic problems. The entire basin of Squirrel River lies north of the Arctic Circle, so that freezing weather prevails during nnx'h of the year. According to reports tlie ice is seldom out of Kotzebue so that Kotzebue can be reached before the miildle of July, and by the middle of September the river.s arc frozen; it is unsafe to count on a mucli later season, though there have been years when the soimd near Kotzebue

The Squirrel River Placers. 309

was not closed before October. Therefore the open season is practically hmited to two months, or about 60 days. Even during tliis period, however, snow and ice form. During 1910 on the night of August 15-16 ice formed on the sides of the streams and on the stagnant pools at an elevation of not more than 200 to 300 feet above the sea. On August 18 the hills around Squirrel River basin were covered with snow far down their slopes, though their tops do not reach elevations of more than 2,000 to 3,000 foot.

Drainage And Relief.

Little is knowTi about the geography and geology of the Squirrel River basin. The main river probably heads against the Noatak basin on the north and the drainage into Ilotham Inlet on the soutli. Broad flood plains traversed by sloughs and marshes occupy the lowlands from 1 to 3 miles wide on each side of the river and appear to be due mainly to the filling of a more deeply eroded older valley by tliick deposits of gravel. Beyond the bottom lands the valley walls slope more or less abruptly to merge with the uplands. Even on the valley slopes, however, there are thick deposits of gravel which extend to elevations of several hundred feet above the normal level of Squirrel River. These deposits are recognizable not only in the Squirrel River basin but also for considerable distances along the Kobuk both eastward and westward.

The larger tributaries to Squirrel River, some of which are 30 to 40 miles long, in their headward portions flow on steep gradients over exposures of bedrock slightly covered with recent creek gravels. Farther down, however, benches, in part rock-cut and in part built of gravels, mark former stream levels below which the present tributaries are incised. In this portion the streams flow in rock-walled canyons, some of which are a hundred feet or more deep. Still farther downstream the creeks debouch from the hilly country and traverse the lowlands of the main river. In this part of their courses the streams are slow and have tortuous meanders and abandoned earlier channels forming sloughs that make approach dif licult ; no bedrock is exposed and probably it is at a considerable depth below the surface.

Little of the upland of the region was examined, so that only a most general description can be given. Viewed from a distance, however, the sky line is more or less irregular, but in general the elevations of the summits are between 2,000 and 3,000 feet. The ridges as a rule show but small undissected areas, the elevation in the main being the result of the erosive activities on the two sides of the divides. Along the summits of the higher ridges pinnacles of fantastically weathered rocks make prominent landmarks and afford excellent exposures of country rock.

Misebal Resources Of Alaska, 1010. Vegetation And Game.

]

Throughout (li* Region the vegetation 13 typically- subarctic and arctic. All the trees show more or less stunting and the number of species is relatively few. Near the larger streams spruce forms a narrow fringii of dark green a few hundreil yards in width. Few of the trees are more than a foot in diameter at tlie base and they taper rapidly toward the top. A few birches grow on the well-drained gravel terraces along the Kobuk, but they are not abundant in the Squirrel River basin, The white and the black birch are useti aa timber; the pro-strate birch, which is of much wider distribution, is too small to be used even for fuel. Willow and alder are found along the smaller sti'eams and necessarily will be an importaol source of fuel on many of the more remote creeks where spruce tft lacking. The larger pai't of the basin is devoid of trees of any kind and the only vegetation on all the near-by flats and the lower hill slopes is rank grass and moss. Although the grass in places is abundant, it grows so rapidly during the long summer day and is so full of, water that it does not make good feed for horses. \Mien touched, with frost, the grass seems to lose the little nourishment it had wheJv green and stock dependent upon it rapidly lose strength.

Undoubtedly in the more remote parts of the Squirrel River ba large gutne, such us liner sinil caribou, may he found, but in the parts near the placer diggings this is not the case, and there are few indications that there has been much game in the region in the recent past. Ptarmigan and water birds, however, are abundant, and may be approached sudicicnllj' close to obtain a considerable number, but it is believed that they are not to be entirely depended upon for food. Fish are numerous in all the streams. Salmon by the hundreds are caught in dragnets in the Kobuk and lower Squirrel River, and grayling may be had in almost all the smaller streams. So abundant are the fish that they may he safely counted on for food. The grayling will usually take either fly or bait hooks, salmon eggs on the eye of a grayling making the best bait.

General Geology.

Geologically the region nianj- of the same features that are seen in parts of Seward Peninsula to the southwest. The rocks of the region, so far as known, belong in the group of met amorphic schists and limestones referred in Seward Peninsula to the Nome group. No further light was obtained as to the ago of these rocks, but little hesitation is felt in assigning them to the Paleozoic or earlier periods. Schists of a variety of different churactei-s were seen in the vicinity of the productive placers. Practically all the schists contain large amounts of chlorite, but some are domiBantly quartzose and others are calcareous.

The Squiebel Biveb Piaceks. 311

Metamobfhio Bocks.

The quartz schists are of two main types; one is a rather fine grained slaty schist of dark, nearly black color, with some carbonaceous material which is, in part at least, graphite; the other type is free from carbon, and the rock in fresh specimens is greenish gray, with mica or chlorite as the principal mineral observed on the cleavage surface and quartz the principal mineral observed transverse to that direction. The carbonaceous phase is lithologically similar to the Hurrah slate of the Solomon and Casadepaga region and the Kuzitrin formation of central Seward Peninsula, especially south of the Bendeleben-Kigluiak Mountains and in the southern part of the Kougarok district.

The calcareous schists, as their name implies, have a high lime content and are more or less schistose. All phases between a slightly sheared limestone and a thoroughly recrystallized schist are represented in this field. In the more schistose varieties there is an abundance of chlorite and mica flakes which increase proportionately as the Ume content decreases. A yellow weathering color is in general characteristic of these calcareous schists, and topograpliically they do not form as prominent ridges as the limestones or some of the more quartzose schists. Some of the calcareous schists undoubtedly represent old sediments deposited contemporaneously with the sandstones which form the quartzose schists, for they appear to be interbedded with them. Some, however, are the sheared equivalents of the limestones, and these may belong to younger horizons than the quartzose schists.

Slightly sheared and metamorphosed limestones, similar in lithologic character to the thick limestones found in the vicinity of all the productive Seward Peninsula placer deposits, are recognized in the Squirrel River basin. In this district, as in the region to the southwest, these rocks make bare white hills practically devoid of vegetation, forming notable landmarks for long distances. Although minerals and structures due to dynamic deformation are developed in places throughout these limestones, the amount of metamorphism does not seem to be as great as in the quartzose schists and some of the calcareous schists. For this reason it seems probable that an unconformity exists between the heavy limestones and the metamorphic schists. This fact has not been definitely proved but seems to be indicated not only by the different amounts of metamorphism but also by the areal distribution of the limestones. No fossils have been found in the limestones of this region, and the prospector should be urged to save any traces of organisms that may be found in the rocks, as they may give a clue to many important problems.

312 MINEBAl- UESOUBCKS OF A1-*SKA, WIO.

Ionbou8 Rocks.

In addition to the eidimontiirv desi;ribed arc iiUo sotnn formed by igneous ngenc:ics, Tlipse rocks arc mainly tlta Ijrtvnsloncs and grpenstoim McliiHtjf. Only a few exposiira* of tliou wpfB , but the cjoso similarity of the other rocks to thosa of Snward Peninsula suggetta that probably, with mori> cJdcnsJTt sLudy of the rcjion, thco old igntwus rocks will bo found to be fairly niimoi'oiiH. All thi> greenatonoa are more or Inss shrarad and metamorphosed and were therefore Introduced in the period preceding the great deformation of the region. None of the f;rant0 noted in parts of Seward Peninsula have bcenobwrved in this roii, and there docs not seem to be much probabihty that ihesi* mora' recent rocka have been injected in the neighborliood of the producttvt placers.

Economic Geology.

As has already been noted, Uie developments in tiio Squirrel Rivw, region have been small, ajid altJioiigli gold prospects are said to hav been found on eight or ten tributaries of Squirrel River mining wag in progress on only one of the streams, namely, Klein Creek. It ia difficult to believe that this is tlie only place where productive exist, for conditions luiuldfroiis to i,lio>,i.' on Klcry Creek are reported at several other places in this basin. With further prospecting undoubtedly other places may be found as rich as the known ground on Klery Creek. There is, however, a strong tendency of prospectors to hold ground on a proved creek and prospect tlie adjacent areas only when driven to it by the exliaustion of the known ground or the inability to secure clnims on a certain creek. Furthermore, the field in which placers may be expected to occur covers a large area, which takes time and nioney to and as yet there are but few men in the region and most of these have not enough capital to undertake any extensive exploration. At tlie time the region was visited by the Survej" geologist there were not over 50 men in the whole region and about a of this number were employed on one claim. Capital hatl not taken hold of the region, and there were few opportunities to work for wages; consequently the camps were run on a partnership basis and few of the men were equipped with the necessary supplies to carry them for a year or so of improductive labor in building drains, etc., preparatory to opening a property. Wagea were said to be $7.50 a day and board for ordiiiarj' miners, but as there was only one company emploj'ing men and ns that company was able to obtain all the help it at So a day the above figures are more or less fictitious. Wliile the labor conditions will undoubtedly change if the camp proves successful, persons should be warned

The Squibbel. Biveb Placers. 313

against going to Squirrel River if they have nothing but wages to depend on. In 1910 there was employment for only a few men, so that without suppUes or funds the venture would be unsuccessful.

Furthermore, the usual wholesale staking of the region has tied up much of the available ground, so that unless the prospector goes to some distance from the productive creeks his chance of obtaining a claim by original location is slight. One is therefore compelled to go to a considerable distance from the proved ground or else buy or obtain a lay on a recorded claim. Any of these choices compels additional expense which the prospector sliould be prepared to meet. Tlie unjustness of the system is well sliown on Klery Creek, where 64 claims have been recorded above the Discovery claim and at least 20 below that point, and yet work has been done on only 10 of the claims and of these probably not more than four or five have produced a thousand dollars during the last year. This statement is not intended to discourage prospecting but only to point out the small amount of work really m progress.

Placebs. Creek Placers.

As Klery Creek is the only stream on which mining is in progress and as two or three claims on this stream were seen in detail, a description of its placers will be given. It sliould be borne in mind that the general facts seen at the placers where mining is being done are to be expected in similar places throughout the field, and the facts learned by mining on one claim are helpful in the understanding of unprospected ground.

The most active work is in progress near the mouth of a small tributary. Jack Creek, a short distance above the Discovery claim. At this place there is a rock-cut gorge with a gravel-covered floor about 150 yards wide. On this floor the stream formerly followed the eastern side, but in order to allow mining the stream was turned to the other side by a roughly constructed dam. Owing to the exceptionally rainy season of 1910 the stream was abnormally high, and three times during the summer the dam was completely waslied away by the floods and some of the sluice boxes with the gold in them were recovered only with difficulty. The upper 12 to 18 inches of gravel in the bed where the stream had been turned aside is removed by shoveling it aside and the larger bowlders are either rolled back upon worked-out ground or are pulled out of the way by a team of horses brought in the spring from the Inmachuk. This stripping is done rapidly and is carried down to a point where the gravels show some "sediment*' or fine mud coating the pebbles and filling the interstices. None of this surface material is put through the sluice boxes, as repeated experiment has shown that it contains

MIKERAL HESOl'KCES OP ALASKA, 1910.

pmcticftlly no gold. Betwpen tlie upper foot or foot and a Iialf ot gravel that is stripped off ami bedrock is 12 to IS inches of gravel wliicli values are obtained. Tbese priivels are typical river wish but have been less recently Iiatidk'd by the stream than tlie upper oneft. The lower gravels, togetlier with ttio upper 6 inches to a foot of difr intctited bedrock, are put through tlio sluice boxes and it is froiQ them tluit tile gold is won.

Bedrock on this ckiiii in mostly scliist, but on the lower end of thd claim aiid continuing downstreBm on the next adjacent claim t massive, much-fractured, and contorted bluish-white limestone standi ing at a high angle and cutting transversely aeroas the creek. Tii( schist sliows many dilTorent phases on the claim that is being mined In part it ia a dark grapliitic slaty selust with numerous small vein* and stringers of quartz. The bands of this schist are not more thi a few ffi't in thtrknens and are interlaminated with somewhat ct careous and quartzose schists. Some of the latter schists are rust}] yollow in color owing to the decomposition of some of their constii enta. The iron mineral from which this iiraonite had been deriv could not be determined, but it was probably in part pyrit*. In least one place on the claim a narrow band of limestone iutedaminatW with the schist was seen. From this description of the bedrock it iS' evident that iithologically the rocks are similar to those in the richer puts of Iho Xoiiie iTjriitn.in llio Irnri OrcLk hjisiii, in tlic Kuugarok, on Ophir and Melsing creeks near Council, in the Solomon and Casadepaga regions, and near Bluff. Tliis resemblance is further strengthened by the relation of the scliists at all these places to the heavy bluish-white limestoues.

Several hundred ounces of gold from tliia claim was examined and the coarseness of the pieces was remarkable. Practically no fine gold was found and few if any pieces of the gold recovered were worth less than one-fourth of a cent. Several nuggets worth 'from $25 to $50 have been found, and wliile the writer was on the ground one nugget weigliing nearly 7 ounces and worth about $125 was picked up in the gravel. In form the gold from this claim is chunky, or in nufiets, but a little wire gold was also seen, though no flaky or scaly gold was observed. The gold is dark but almost never black and shows few signs of recent movement. Although some of the camera have been rounded the gold as a whole does not appear to have traveled far. In fact, many pieces aie sharp and angular as if but recently unlocked from the parent ledge. Some of the nuggeta have pieces of the country rock still adhering to them. The most abundant mineral attached to the gold is quartz of the same physical aspect as the quartz in the strings and lenses in the schist. Black graphitic slaty schist is also attached to the gold in some of the specimens, and the way in which the gold forms filaments in tliis rock shows indis-

The Squiebel River Placers. 315

putably that some of the placer gold has been derived from this kind of country rock.

Estimates as to the value of this ground are of Uttle use, for the nuggety character of the gold makes the tenor range between wide limits. It is reported that over 190 ounces was cleaned up from about six box lengths shortly before the visit by the Survey geologist, in 1910. At the time of the visit a clean-up of 120 ounces was made from about four and one-half box lengths. Tliis is equal to a bedrock surface of about 500 square feet, so that the production from this cut was nearly $4.50 per square foot of bedrock. A working force of 15 men were able to strip and shovel into sluice boxes this amount of ground in a little over a day. The exact width of the pay streak is not known, for all the work so far has been only on the eastern side of the claim and the western margin of the productive ground has not been reached.

Water for sluicing is obtained from Klery Creek by running a hydrauUc hose several hundred feet upstream and bringing the water thus obtained down on as flat a grade as can be maintained. This supply, however, does not furnish an adequate head, so that some other method will have to be used. But sUght difficulty' should be experienced in obtaining a satisfactory supply, for the volume is ample for the present demands. No accurate measurements of the volume of Klery Creek were made, but the fact that a crossing, even on a riffle, could not be made in less than 2 J feet of water, in a current of such speed that care had to be taken in keeping one's feet, shows that several thousand miner's inches is probably available during a season such as 1910. It should be noted, however, that last year was an abnormally wet one, and estimates based on observations during that time are undoubtedly above the average.

Few assays have been made of gold from this claim, but on a sample submitted to the assayer of the Nome Bank & Trust Co. a fineness of 888 was determined. Tliis would give a value of $18.37 an ounce.

In the concentrates collected with the gold in the sluice boxes magnetite is the most abundant mineral. This forms a much larger proportion of the concentrates than it does in those near Nome. Together with the magnetite are some ilmenite and a little pyrite and limonite. These iron minerals probably are derived mainly from the greenstones and greenstone schists, although the pyrite and its accompanying limonite may have come from veins in the schists or from the vicinity of the limestone-schist contact, a place frequently mineralized in other regions. Garnet, or so-called ruby, so commonly found in the concentrates from Seward Peninsula, is relatively rare and forms but a small proportion of the black sand. The small amount found is due to the absence of this mineral in the adjacent schists derived from

316 Mineral Eesoubces Op Aiaska, 1911).

ignaous and sedimentary rocks. None of tlie rare heavy minerab have sit far hwii rcrognized in the cnnceotratfts.

About a mile a quarter upstream from this claim is anoth? oUim, wiivre gold similar in physical uliaraottr has been found. Wurfe on this ground has been carried on by a crew of only four men and miiinlyof (lam building and bringing up a bedrock drain, so that only a small production had been made and the opportunity of examining a large amount of gold was not afforded. It. seems certaio, however, tliat the from tliis claim is of the same chunky cliaraUr as on tlio lower claim, although the proportion of fine gold ia larger and tlio nuggets, us a rule, weigh Ichs. From the shape of the gold it is beheved that it has not traveled far.

Midway between these two claims the gold is of an entirely different character, although the general geology shows no market! changA ejtcept that the limestone is more remote and the canyon character of the valley ia more pronounced. The gohl from a claim in thi locality ia practically all in fine bright scales. No nuggets worth mora thun a few cents each have been recovered, though several hundred dollars' worth of gold have been won. The scales are all nearly of tlu s&nio size, no lluur gold being seen. All the flakes are of a bright gold color with no tarnished nor black coating. No pieces witk' quarts or other foreign material attached were seen. Tliis gold was of the type morally known to tin* miners as "bar" gohl and showed by its physical character that it had traveled much farther from the ledge from which it was derived than the gold either upstream or downstream from this place.

Gold similar to this "bar" gold has also been found downstream from the first-described claim. It is identical in all essential respects with the one just described and has probably had a similar history. The fact that this gold has traveled farther from its parent ledge is indicated by the higher assay value of the gold. It is not possible to give its precise assay value, for the sample that was tested was mixed with nugget gold from one of the claims farther upstream. This mixed sample, however, showed a higher gold content than the nugget gold previously quoted as wortli $18..37 an ounce, so the difference is probably to be assigned (o the greater fineness of the "bar" gold,

Origin Op The Gold.

The distribution of the gold and the differences in the physical character presented by this mineral from the several claims in this stretch of about 2 miles present problems of economic importance. It is believed that the coarse nuggety gold on the two claims has been derived from near-by areas of bedrock and has therefore not traveled far from its source. Po-ssibly some of it had been concentrated in earlier stages of the valley development and was subsequently recoil-

The Squirrel River Placers. 317

centrated in the present streams, but the movement of the gold by this process must have been relatively slight. On the other hand, the fine flaky gold found downstream from tlie areas of coarse gold seems to represent the smaller, ligliter particles which, because of their size, have been carried farther from their source. Such a process of sorting is analogous to the well-known distribution of gold in a sluice box, where the larger, heavier particles are found toward the head end of the box and the smaller, lighter pieces near the foot or discharge end. According to this theory there are several localities of mineralization cut by Klery Creek, each being rather close to the areas of heavy gold, whereas in the intermediate regions the stream has not been so close to regions of as great mineralization and the gold has been derived from the areas upstream.

Too little is known about the region to determine beyond question whether the mineralization is confined to a single zone or whether there are a great number of mineraUzed zones, but from the number of places where gold has been reported in the Squirrel River basin it seems probable that there are at least several and possibly many zones of mineralization. Further study of this important question is necessary, for it affects the future of the region. Not onlj is it important in determining the probable area in which gold placers may be expected, but the information is also valuable in determining the trends of the placer ground. From the experience in Seward Peninsula it is beUeved that the contact of the heavy limestone and the graphitic or quartzose schists is one of the most favorable localities for searching for placer deposits in this group of rocks. This experience seems to be borne out in part by the work on Squirrel River, for the richest claim so far discovered has been near this contact. That there are other places where mineralization has been pronounced can not be doubted, and the prospector should therefore not place undue emphasis on the above suggestion.

Bench Gravels.

So far only the shallow creek gravels in the stream beds have been exploited. There are, however, bench and high-level gravels in this region as well as the broad fillings of the main stream valleys wliich are possible sources of mineral wealth. None of these older gravels have been prospected as yet, and therefore suggestions as to their probable value or character are tentative and subject to revision when more information is obtained. The lower benches already noted as occurring at several different elevations above the tributary streams, such as Klery Creek, seem to have had essentially the same method of formation as the known auriferous creek gravels. It is therefore believed that where these benches have been developed in the neighborhood of bedrock mineralization they will produce placer

818 AUNEBAL EESOUaCES OF AlJt£KA, 1910.

gold. Most of tlie benches of tlus character on Klery (Veck had bill small length or breadth, so that only dJacontinnous deposiu resulted- Such benches, however, may afford rich pockets of aurifei-ous griiv wliich would well repay exploitation. Many of the benches sem to be covered with muck and turf, wliich suggests that the gravels km frozen and will require thawing apparatus.

The higher gravels, which are of wide extent and not only cover th lower slopes of the Squirrel River basin but also extend botli up and down stream along the Kobuk. present problems much more di& cult to interpret. The origin of these gravels can be determined only by 11 general survey of a large area in the lower part of the Kobuk Valley supplemented by numerous good sections of the deposits by of prospect shafts. The cliaracter and distribution of tiiese Iiigh-level gravels strongly suggest that they liave not been foi-mcd by nomial fluviatUe action. There is a possibility that they may mark marinA deposition, but it seems more probable that they are tlie outw deposits from ancient glaciers that at one time occupied the m eastern part of the Kobuk Valley. If tliis interpretation is correct there is small probahihty that economically profitable placers will found in gravels. Although outwash deposits may contain gold| it is believed that normally the valuable minerals are so dissemiuatod that, except under conditiooB of subsequent concentration, they not be profitably extracted. These liigh gravel-plain deposit? co: largely of rolled quartz pebbles. No striated fragments or other marks of direct glaciation were observed. The physical condition of these gravels with resjiect to frost is not known. As a rule, gravel deposits at any considerable elevation above the adjacent streams are so well drained that they are not permanently frozen. At several places wliere these gravels arc exposed in the valley walls of the tributary streams there are indications that they are not frozen. These places, however, do not give conclusive evidence of the conditions of the gravels in the intermediate area between two streams, wliere the gravels are not exposed to the light and air and wliere the ground-water level rises so tliat tlie gravels are not as well drained. From the character of the surface in some of tiiese areas wluch are less well drained it seems certain that permanently frozen ground will be encountered.

No prospecting has been done in the deeper gravels that form part of the flood plain of Squirrel River, so that no definite information as to the presence of placer ground there is available. It is understood that prosjiectors have found colors of gold on many of the bars and in shallow holes which did not reach bedrock. The ground was frozen and the necessary machinery for exjiloriug the was not at hand, so that the deep ground was abandoned for the more easily worked sliallow creek diggings. From the experiences on Seward Peninsula it seems questionable whether important placer

The Squirrel River Placers. 319

deposits will be discovered in these flats. It should be reiterated, however, that the data for basing a decision are inadequate, and the above suggestion is little better than a guess warranted only by the desire to prevent the reckless expenditure of time and money on ill-considered projects.

Summaby Of Conclusions.

Taken as a whole, the Squirrel River region is one in which the small amount of prospecting already done has disclosed productive placers. The extent of these has not been determined, but it is believed that the region affords a good opportunity for industrious and capable prospectors. The rigors of the climate and the short working season are against the development of a large camp and should dissuade the incompetent from invading the new district in a 'stampede.'' The similarity of the placers so far discovered to those in the more productive parts of Seward Peninsula gives faith in the future of the region. Tliis beUef would be further strengthened if prospecting should show the existence of valuable bench or deep deposits capable of supporting mining during the winter season. A large output in the near future is not but adequate returns for intelligent and competent exploitation are indicated by the present results.

Index.

A. Page.

Acknowledgments

Administrative report 5 U

Alaska, allotments for survey of 7-8

metalliferous deposits in, map showing In pocket.

Alder Creek, discharge of 215

American Creek, discharge of 212

See also Discovery Fork. Amygdaloids, copper-bearing, occurrence of. 8(>-87 Animals of Shungnak region 279-280

of Squirrel River region 310

Antimony, occurrence of 91-92

Asbestos, prospects of, in Shungnak region ... 304 Aurora Mountain, copper prospects on 300302

B.

Bachelor Creek, discharge of 201

Banner Creek, discharge of 194

operations on 167

Barney Creek, discharge of 216

Basalt in Valdet Creek district 117-118

Beaver Creek, basin of, operations in 165

Bemers Bay region, gold-bearing deposits in. 67

operations in 95-98

Birch Creek, basin of, description of 196

basinof,nTiscellaneous measurements in. 197

discharge of 196.197

Bismuth, occurrence of 93

Bonanza Creek, discharge of 199

Bonanza Creek ditch, discharge of 200

Bonanza mine, Copper River region, vicinity

of, sketch map of 85

Bonnifield region, coal deposits in 231-232

geography of 218-220

geolog>' of 220-221

gold placers In 221-229

lode mining in 229-231

map showing 220

Brooks. Alfred H., Administrative report by. . 5-14 report by, on .\iaskan motalliforous loads. 43-93

on The mining industry in 1910 21-42

on surveys of puhliclands in Alaska.. 15-20 Buckskin Creek, discharge of 207

California Creek, coal on 234

mineral resources on. 224

Canyon Creek, discharge of 204

operations on Iti9

Capps, S. R., report by, on Mineral resources

of the Bonnlfleld region 218-235

and MofTit, F. H.,on copper deposits of

the KoLsina-( hi tina district 8-86

Central Alaska, map showing 48

98319*— Bull. 480—11 21

Page.

Charity Creek, discharge of 191

Chatanika Flats, operations on 156

Chatanika River, basin of, discharge from

streams In 18S-191

basin of, operations in 155-157

discharge of 180, 189-190

horsepower of 180

Chena River, basin of, discharge of streams

In 184-187

Chicken Creek, operations on 169

Chisna River, operations on 126

Chistochina district, geology of 124

operations in 124-127

Chistochina River, basin of, map showing. . . 114

Chute Creek, mineral resources on 230

Circle district, description of 194-195

gaging stations and measuring points in . . 195

operations In 160

Cleary Creek, operations on 155-156

See also Klery Creek.

Cliff mine, description of 29-31

Climate of Shungnak region 276-278

of Squirrel River region 308-309

Coal, delay in development of 23

deposits of, in Bonnifield region 231-235

descriptionof, in Matanuska Valley... 130-138

prospects of, in Shungnak region 304

suspension of mining for 42

Coal Creek, operations on 172

Cobalt, occurrence of 92-93

Copper, amygdaloidal deposits of 86-87

ores of, associated with greenstones and

limestones 82-87

associated with greenstones and sediments 80

disseminated in intrusive rocks 80

in greenstones and argillites 80-82

in zones of igneous metamorphism. . . 74-79

production of 25-26,27-28,31-33

on Prince of Wales Island 99-100

prospects of. in the Shungnak region.. 300-302

Copper Mountain region, map showing 74

Copper River region, gold-bearing lodes foimd

ore deposits of 48-49

placer mining in 38

Cottonwood Bay, diagrammatic section near. 78

gold-bearing deposits near 69

Craigie Creek, prospects on 146-147

Cretaceous formations in Matimuska coal

fields 129,130

Cripple Creek, basin of, operations in 157-158

Crooked Creek, basin of. description of 198

basin of, miscellaneous measurements in. 201

operations in 161-163

discharge of 199. 216

opnuiiotw on irei-ltei

lwnipy, opfrmlUmsBl 1J7

, nilnrtllttd, owufrrawor n-70

lIlMOTery Fork of AnwIcM Cnti, dli-

Uamf I'mk, opwiMonaon

Doutln* laliuid, (mlocU'iliddi nuipac M

DrylTnU. butnol, cwlbnlniii ZU

mliwml raoureM on as-JM

KaklD, n.M.,aDclBnilth, f. S., rriurt hy.on The ShuD)[iuk rrgion. Kaliiili

VBllej Ki-au6

KJIiult Ciwk: cllachr£ nl IMJH

KllsworUi. s,, nad Parkcf, c, 1.., report b;, on PlaoK mining 1q ibt

yukon-Twuiu ncloi in-tTX

on WBUrmipply of thr YtikoD-

r Angel f.Twk, prospepls on.

,. us-)w

banks I'ropli, oprmtions on

banks illitriul, cIcMTlpifon d

KWinB BUlions and nicks

na

flgie showing

. M

yield work in IB 10

Kl!>b orBliimgTiHk rfElon

ul SqulTTpi Rivar region. . I'tih Preck . huln of. npcrBI Ini

Klslihook OrMk, jirosiwcW on

yinl Creek, opwalioni on

Flume Creek, illsclutBeoI

Forly-nvi- I'up, dlsuhsrui-of

rari]-nile distrkl, kdeIhk iluloai

measuring puinla uf...

lotmlion o[

Furlymlle Ttlrer, baaln arilescrlptloil of

Foiirlh of July Creek. operBt

Fisnlilln Creek. DpeTSIIons o

Fiylngpiin Creek, dlwhwce i

proapeotlng on

prxKliuiUon ol Olnclil ilrpMlU In the St ()old, ntt of dUbIdg. In Ibe MIUrDd

ilepoxlUol, In AlulDt .. JS

In BonnUtld R( TZh3B

In niver regtoo iOt-Ut

in IDlnideil neka, . .

spire showing ra.KM

figure Bhowine

In Sbungntk nylon

In BDutheuleni Alukii...

in Willow Creek lu-lM

jilKvr mining of, on Flat OrMk . . .

on Utile Creek

on opblr Creek

on OtlerCrMk

on Spruce Creek

on WQloo

un YankaeCnwk

liroduetionot..

fromludm

Irom plwen ,

wum ol. in 'hlmi dlMrlrl w2

Oold Creek dlithct,openUlun*ln...

tiold King Creek, mineral nBOurcason 2-3H.J

Oold plaoenilD BoddUIcM leclon Ill

In binoko-Idltwvd Mttaa.oricnot... MMMfl

InSqulirelKImrncko USlf

In Cirok reKlun IJO-lll

hi Viikoii-TaHanii region, pro'lurtlon

Iroui IS-17I .

iloldflreuni Creek, basin ol, deacrlption

of IfO

basin ol. opeistlons In lAI-iai

ilranlte, -liearlng dfiposlls in (S

In Viildei Creek district UT-118

liiBDodlDTlIe, gold-beoriog deiusits in m

Urant, U. S., snd , D. F., on copperbearing lodes In ereeiulonn and

orgliiiteB tMl

llmvelsol Squirrel River nloii... 31-3U, IIT-llV

ol ShuoEoali niglon 3g9-Vl

ilretilones, copper deposits nmslUed

with n

flruliflnkD Creek, mineral rnnurceson. 231

(Jmbslnke . gold plimiii on ifiO-lS

liypsum. production of fl

Happy , orwralloni on. MM Ml

IlMKt Creek, mineral resouroaoD m

lletts Inlet dbjlrlet.opetstlonsln in-ISl

, n, F., and Grant, U. S., onoopper-

bearing lodes In

llomrcitake Creek. |!e of,.,.

niinerairesourciiaou.-

operullons on.

Itot Sprlngii dialrici, operations III IlutdUnson. CnNsk, dlscharie dI. ..

Index.

I. Page.

Idltarod, description of 241-242

discovery of gold at 237-238

Iditarod district, future of 269-270

outlying placer-gold localities near 267

production of 266-267

See also Innoko-Iditarod district. Igneous rocks of the Squirrel River region . . . 312

Independence Creek, operations on 163

Ingle Creek, operations on 170

Innoko-Iditarod district, description of 236-237

geography of 239-240

geologic sketch of 243-245

gold-bearing deposits in 70

placer-gold deposits in, origin of 245-246

map showing 236

transportation and settlements in 241-243

Intrusive rocks, copper ores disseminated in . 81

occurrence of 57-68

Investigations, details of 8-13

Iron, occurrence of 90-91

prospects of, in the Shungnak region 303

J.

Jade, prospects of, in the Shungnak region... 304

Junction Creek, discharge of 194

Juneau district, gold-bearing deposits in... 60-61

operations in 95-96

Jurassic formations in Matanuska coal fields. 129

K.

Kansas Creek, mineral resources on 230-231

Kasaan Peninsula region, copper-bearing

deposits in 80

operations in 100-101

Katz, F. J., report by, on A reconnaissance of

the Willow Creek gold region. . 139-152

Kechumstuk Creek, discharge of 206

Kenai Peninsula, gold-bearing deposits in. . . 62,70

mining in 32

Ketchikan district, copper-bearing deposits

in 74-79

gold-bearing deposits in 61-62, 68-70

operations in 98, 99

See also Kasaan Peninsula and Prince of Wales Island.

Klery Creek, operations on 312-316

See also Cleary Creek. Knopf, Adolph, on amygrla-

loids ' 86-87

on the occurrence of tin 88-90

report by, on Mining in southeastern

Alaska 94-102

on The Eagle River Region 10-111

Kogoluktuk River, operations on 294-296

Kotsina-Chitina district, copper deposits in. . 82-

copper prospects in, map showing S2

production of metals from 28

Kuskokwim basin, lodes in 51-52

mining in 39-40

Paleofoic formations in 54-55

Kuskokwim Mountains, description of 243-245

Labor in Chistochina district 126

In Clrde district 160

Lands, public, in Alaska, sorveyB of 16-20

Page. Lead, occurrence of 87-88

prospects of, in Shungnak district 303

Lignite Creek, coal beds on 233-234

Lime Creek, operations on 126

Little Chena River, discharge of. . . 180, 184-185, 186

horsepower of 180

Little Creek, operations on 247-249

Little Eldorado Creek, operations on 156-157

Lodes, metalliferous, distribution of 44-53

Lucky Gulch, operations on 122

M.

McLain Creek, operations on 164

McManus Creek, discharge of 191

Maddren, A. G., report by, on Gold placer mining developments in the

Innoko-Iditarod region 236-270

Manmioth Creek, discharge of 200

operations on 161-162

Marble, production of 42

Martin, G. C, report by, on A detailed survey of part of the Matanuska coal

fields 128-138

Mastodon Creek, operations on 161

Matanuska basin, coal field of, geology of. . . 128-131

coal field of, map showing 130

lodes in 49-51

structure sections in, plate showing 136

MendenhaU, W. C, on rocks of the Ambler

River basin 285,287

Mercury, occurrence of 93

Mesocoic formations, occurrence of. 56-58

occurrence of, in Matanuska coal fields. . . 130

in Shungnak ron 284-286

Metals. See Copper, Gold, Silver.

Metamorphic rocks of Shungnak region 281-284

of Squirrel River region 311-312

Miller Creek, discharge of 187

operations on 163

Miller Gulch, operations on 124, 125

Mineral land laws, abuse of 21,267-260

Mining, progress of, in 1910 21-23

Mission Creek, discharge of 211

drainage basin of, description of 210,211

drainage basin of, miscellaneous measurements in 212

Moffit. F. H., on copper-bearing amygdaloids. 86-87 on copper deposits of the Kotsina-Chi-

thia district 82-87

report by, on The Susitna and

Chlstochlna districts 112 127

Molybdenite, occurrence of 93

Monahan ttmnel, description of 120-121

figure showing 120, 121

Montana Creek, discharge of 209

Moose Creek, mineral resources on 222

Mosquito Fork, discharge of 206

Moimt Andrew mine, plan and cross section

of 76

Mulchatna region, mining in 39

N.

Nabesna River basin, copper-bearing depos-

itsin 78

gold-bearing deposits in 09

Napoleon Creek, operations on

.. NurUi Fork til Dlreh Cmk . InlDiCP buln

Fk of FortymlU Blw, llwhMjr

Paei.

im-iM f. ' xa

.. aM

.. m

Kx.

hail

..

. Iimi

m.af

B.

S,Upl*Ti*.rt.t dlHrtei, DiraUlcuu In.

.. Mi-

.. m iii-ia .. a

Simm

bulD of, pteiag sMUoiu and meaMff

n,

.. in

in-a

.-

Mo-2B3

. m 3sa-3a

uitw. JBcrtpilomrf.

hotsrpowCT of

F.

.. ai

2M-M

future o(

0. I, ud EILwofUi, C. E„ rep.

be

K-l'ltodMln

(Mldplwerslii

mrip.howl.it

"lift of

stream Rravels of

ITL-usher Crook. dralDBgi' I.mIu of, dfacrip-

dTBiniiKC basin ol. operalioro In

iM-ias u

Xw.B7

. w-icts

dfjiosilain

8!Blc Cwk distrttl. depwiiM of gold to

ks

00-301 12.V13fl

ruDliealluna issued or Id pTEpamlJon

QLiaWraary fonuairona, owuneuM of. .

operalionaln , t-llS

ami Eakln. H. wpon by, on Tt. Shiinpiafc nekm, KoTmk it

iey m-m

posllsof 71

KriCmk, mineral resouros on

Kili'yCmik.oprniltQnaon...

Roowvell rrsBk, mineral rtsourcm on

Ruby , poppfi prtBpPCls 01)

8oiTebrrk,di3<:hiu-Rro' 18S,W

Soulh Fork of Focl>-nilio , iwstn of, de-

Index.

Page.

Southeastern Alaska, map showing 40

production of gold in 95

Spencer, A. C. on ore deposits of Treadwell

mines 67-68

Spruce Creek, operations on 24250

Squaw Creek, discharge of 204

Squaw Gulch, operations on 169

Squirrel River, basin of, map showing 306

Squirrel River region, climate of 306-309

drainage and relief of 309

economic geology of 312-319

fish and game In 310

future of. ' 319

general geology of 310-312

location of 306-307

map showing 272

origin of gold in 316-317

placers in 313-319

transportation In 306-306

vegetation of 310

Steele Creek, discharge of 204

Sulphur, deposits of 42

Sunrise district, minhig in 38

Susitna basin. lodes in 49-1

map showing 114

muling hi 38

Paleozoic formations in 54

T.

Tanana Rivor, drainage basin of, description

of 192-193

Tatlanika Creek, basin of. coal beds in 234

mineral resources on 224-225

Tenderfoot Creek, operations on 167

Tertiary formations, occurrence of 58-9

occurrence of, in Matanuska coal fields ... 130

in the Shungnak region 284-286

Timberline Creek, prospecthig on 124

Tin, occurrence of 88-90

Totatlanika Creek, mineral resources on 222-223

Transportation in Circle district 160

in Squirrel River region 30(>-308

in Valdez Creek district 116

progressof 23-24

Treadwell mines, improvements at 95

ore of 67-68

Tungsten, occurrence of 88-90

U.

Unaloska Island, gold-bearing deposits on. . . 06

Valdez ('reek, course of 115

new channel of 118-119

Page.

VoIdeE Creek di8trk!t,economte geology of.. 119-124

general geology of 117-119

geologte sketch mapof 117

location of 112-113

transportation in 116

Vegetation of the Shungnak region 276-279

W.

Wade Creek, discharge of 207

operations on 169

Wages of miners in the Shungnak region 291

In Circle District iro

on Chisna River 126

Walker Fork, discharge of 207

operations on 168-ltW

Washington Creek, discharge and horsepower

of. ISO

drainage basin of, description of 217

Water power in Yukon-Tanana region 17&-180

Water-supply survey, data and methods of. 174-176

White Creek, gravels of. 123

Willow Creek region, geography of 139-142

geologic sketch map of 143

geology of 142-143

gold lodes in 144-146

gold placers in 150-151

mining in 32-33

operations in 256-281

prospects in, description of 146-150

summary description of 151-152

Wood River basin, coal beds in 235

Woodchopiwr Creek, operations on 172

Y.

Yankee Creek, operations on 252-253

Yukon region, gold-bearing deposits in 63

lode mining in 33-35

lodes In 51-52

Paleozoic formations in 54-55

placer mining in 39

Yukon-Tanana region, hydraulic development in 179

map showing 52

operations in 153-172

precipitation in 176-178

water power in 179-180

water supply of. 173-217

winter run-off in 180-181

Z. Zinc, subordinate occurrence of 87-66

Recent Survey Pubi.Ications On Aiaska.

[Arranged geographically. A complete list can be had on application.]

All these publications can be obtained or consulted in the following ways:

1 . A limited number are delivered to the Director of the Survey, from whom they can be obtained free of charge (except certain maps) on application.

2. A certain number are delivered to Senators and Representatives in ('congress for distribution.

3. Other copies are deposited with the Superintendent of Documents, Washington, D. C, from whom they can be had at prices slightly above cost. The publications marked with an asterisk in this list are out of stock at the Survey, but can be purchased from the Superintendent of Documents at the prices stated.

4. Copies of all Government publications are furnished to the principal public libraries throughout the United States, where they can be consulted by those interested.

General.

*The geography and geology of Alaska, a summary of existing knowledge, by A. H.

Brooks, with a section on climate, by Cleveland Abbe, jr., and a topographic

map and description thereof, by R. U. Goode. Professional Paper 45, 1906,

327 pp. II. Placer mining in Alaska in 1904, by A. H. Brooks. In Bulletin 259, 1905, pp. 18-31. The mining industry in 1905, by A. H. Brooks. In Bulletin 284, 1906, pp. 4-9. The mining industry in 1906, by A. H. Brooks. In Bulletin 314, 1907, pp. 19-39. *The mining industry in 1907, by A. H. Brooks. In Bulletin 345, pp. 30-53. 45 cents. The mining industry in 1908, by A. H. Brooks. In Bulletin 379, 1909, pp. 21-62. The mining industry in 1909, by A. H. Brooks. In Bulletin 442, 1910, pp. Railway routes, by A. H. Brooks. In Bulletin 284, 1906, pp. 10-17. Administrative report, by A. H. Brooks. In Bulletin 259, 1905, pp. 13-17. Administrative report, by A. H. Brooks. In Bulletin 284, 1906, pp. 1-3. Administrative report, by A. H. Brooks. In Bulletin 314, 1907, pp. 11-18. Administrative report, by A. H. Brooks. In Bulletin 345, 1908, pp. 5-17. 45 centfi. Administrative report, by A. H. Brooks. In Bulletin 379, 1909, pp. 5-20. Administrative report, by A. II. Brooks. In Bulletin 442, 1910, pp. 5-19. Notes on the petroleum fields of Alaska, by G. C. Martin. In Bulletin 259, 1905,

pp. 128-139. The petroleum fields of the Pacific Coast of Alaska, witli an account of the Bering

Kiver coal dcxjosits, by G. C. Martin. Bulletin 250, 1905, G4 pp. Markets for Alaska coal, by G. C. Martin. In Bulletin 284, 1906, pp. 18-29. The Alaska coal fields, by G. C. Martin. In Bulletin 314, pp. 40-46. Alaka coal and its utilization, by A. H. Brooks. In Bulletin 442, 1910, pp. 47-100. The possible use of peat fuel in Alaska, by C. A. Davis. In Bulletin 379, 1909,

pp. 63-66. The preparation and use of peat as a fuel, by C. A. Davie. In Bulletin 442, 1910,

pp. 101-132. *Th(? distribution of mineral resources in Alaska, by A. H. Brooks. In Bulletin 345,

pp. 18-29. 45 cents. xMineral resources of Alaska, by A. H. Brooks. In Bulletin 394, 1909, pp. 172-207. *Methods and costs of gravel and placer mining in Alaska, by C. W. Purinsrton.

Bulletin 263, 1905, 362 pp. 35 cents. Abstract in Bulletin 259, 1905, pn. 32-46. Prospecting and mining gold placers in Alaska, by J. P. Hutchins. In Bulletin

345, 1908, pp. 54-77. 45 centfl. Geographic dictionary of Alaska, by Marcus Baker; second edition by James.McC-or-

mick. Bulletin 299, 1906, 690 pp. *Water-supply investigations in Alaska in 1906-7, by F. F. Ilenshaw and C. C.

Covert. Water-Supply Paper 218, 1908, 156 pp. 25 cents.

328 suBVKV I'i'Hlicathjnh on alaska.

Topograpkir map*.

Alaska, topographic toity ocule, 1 : 2,500,000; preliminary edition; by B.

Goode. ContaincHl lu I'mltKH'innal Piip<-r 45. Not eepoiately. Map o( Alaska Khowing of minLTal rewjurcEn; scale, 1 : 5.000,000; bjr

A. II. Broobi. Cintained in Uiilletio :145 (in uockeH. Map of Alaska; scale, 1 : 5,000,000; by Alfred U. Brooks.

BoirrHXABTXiur ai-asxa.

Preliminary report on the Kolcbiknn mining dinLricI, Alaska, with an introductan* kelrh of the geology of noulheaHlern AIeu, by Alfred H. Briwhs rrofionU Paper I. 1902. 120 pp. 26 celia.

The Porcupine placer dUtrict, Alaska, by C. W. Wright. Bulletin IWM. 35 ppi,

Admiralty Island, Alaska, by C. W. Wright, pp. 138-154. Bulletin 287, 190(,

101 pp. Lode mining in poulheaKtern Alaska, by F. E. and C. W. Wright. In Bulletin 23*,.

1S06, pp. 30-63. NonmetaJlic deposits of eoulheaatem Alaska, by C. W. Wright. In Bulletin 284,

1908, pp. 54-60. The Yftkutat Bay rion, bv R. 8. Tarr. In Bulleliu 284. !B06, pp, Gl-64. Lode mining in southeastern Alaska, by C. W. Wright. In Bulletin 314, 1907:

pp. 47-72. NonmelalliferouB mineral resources of southeastern Aluskn, by C, W. Wright.

Bulletin 314, 1907. pp. 73-81. ReconnaiiwHnce on the Pacific coast from Yakutat to Alsok River, by Eliot Blac

welder. In Bulletin 314, 1907, pp. 8288.

*Lode mining in Mutheoatem Alaska in 1907, by 0. W. Wright. In BullMin

pp. 78-97. 45 cents, The building Bloneu and mati'rinU of soiilheanlern Alaska, by I.'. W. Wight. Id

Hiillc'iid 345, 190S, pp. IHi- Vlii. 4S <, Copper depot-ils on Ka.saan Penin.''Ulai Prince of Wales Island, by C. W. Wright and

8iduey_ Pa%e. In Bulletin 345. 1908. pp, 98-115, 45 cents. The Kelchikan and Wrangell mining districle, Alaska, bv P. E. and C. W. Wright.

Biillelin347, 1908,210 pp. The Yakulal Bay region. Alaska: Phvi-ioRraphv and glacial geology, by It. S. Tarr;

Areal geology, by It. S. Tarr and B. S. Butler. Professional Paper G4, 1909,

Mining in southeastern Alaska, by V. W. Wright, In Bulletin 379, 1909. pp. 67-8. Mining in southeastern Alaska, by Adulph Knopf. In Bulletin 442, 1910, pp. 133-

143, The occurrence o( iron ore near Haines, by Adulph Knopf. In Bulletin 442, 1910,

pp. 144-146. A water-power reconnaissance in southeastern Alaska, by J, C. Hoyt. In Bulletin

442, 1910, pp. 147-157. Geology and mineral reiHources nf ilir HeniiTs Bay region, Alaska, by Adolph Knopf.

Bulletin 440,1911,58 pp.

Tojioffra/thur maps.

Junoau special <juadraugle; scale. 1 : (12.500; by W. J, Pptetw. Por sale at 5 centa

each or $3 per hundred. Berners Kay special map; scale. 1 : 02,500; by R. B, Oliver, Fur sale at 5 centa

each or per Imndri'il. Topiraphic map of the Juneau gold belt, Alaska. Contained iu Bulletin 387,

Plate XXXVI, 190li. Not iH.-ned separately,

GONTROIXSR BAT. PRIITCE WlI.LIAlf SOmTD, AND COPPER EtIVXS BEOIOXg.

The mineral resources of the Mount Wrangell district, Alaska, by W.C. Mendeohall, Professional Paper 15, 1903, 71 pp. Contains general map of Prince WUliam Sound and Copper River region; scale, 12 miles inch. 30 cenlfi. Bering River coal field, by G, C. Martin. In Bulletin 259, 1905. pp. 140-150.

Survey Publications On Alaska. 329

Qape Yaktag placers, by G. C. Martin. In Bulletin 259, 1905, pp. 88-89.

ltes on the petroleum fields of Alaska, by G. C. Martin. In Bulletin 259, 1905,

pp. 128-139. Abstract from Bulletin 250. The petroleum fields of the Pacific coast of Alaska, with an account of the Bering

River coal deposits, by G. C. Martin. Bulletin 250, 1905, 64 pp. Geology of the central Copper River region, Alaska, by W. C. Mendenhall. Professional Paper 41, 1905, 133 pp. Copper and other mineral resources of Prince William Sound, by U. S. Grant. In

Bulletin 284, 1906, pp. 78-87. Distribution and character of the Bering River coal, by G. C. Martin. In Bulletin

284, 1906, pp. 65-76. Petroleum at Controller Bay, by G. C. Martin. In Bulletin 314, 1907, pp. 89-103. Geology and mineral resources of Controller Bay region, by G. C. Martin. Bulletin

335, 1908, 141 pp. Notes on copper prospects of Prince William Sound, by F. H. Moffit. In Bulletin

345, 1908, pp. 176-178. 45 cents. Mineral resources of the Kotsina and Chitina valleys. Copper River region, by F. H.

Moffit and A. G. Maddren. In Bulletin 345, 1908, pp. 127-175. 45 centi. Mineral resources of the Kotsina-Chitina region, by F. U. Moffit and A. G. Maddren.

Bulletin 374, 1909, 103 pp. Copper mining and prospecting on Prince William Sound, by U. S. Grant and D. F.

Higgins, jr. In Bulletin 379, 1909, pp. 87-96. Gold onPrince William Sound, by U. S. Grant. In Bulletin 379, 1909, p. 97. Mining in the Kotsina-Chitina, Chistochina, and Valdez Creek regions, by F. H.

Moffit. In Bulletin 379, 1909, pp. 153-160. Mineral resources of the Nabesna- White River district, by F. H. Moffit and Adolph

Knopf. In Bulletin 379, 1909, pp 161-180. Mineral resources of the Nabesna- Wnite River district, by F. H. Moffit and Adolph

Knopf; with a section on the Quaternary, by S. R. Capps. Bulletin 417, 1910,

64 pp. Mining in the Chitina district, by F. H. Moffit. In Bulletin 442, 1910, pp. 158-163. Mining and prospecting on Prince William Soimd, by U. S. Grant. In Bulletin

442, 1910, pp. 164-165. Reconnaissance of the geology and mineral resources of Prince William Sound,

Alaska, by U. S. Grant and D. F. Higgins. Bulletin 443, 1910, 89 pp. Geology and mineral resources of the Nizina district, Alaska, by F. H. Moffit and

S. R. Capps. Bulletin 448, 1911, 111 pp.

Topographic maps.

Map of Mount Wrangell; scale, 12 miles inch. Contained in Professional Paper 15. Not issued separately.

Copper and upper Chiatochina rivers; scale, 1:250,000; by T. G. Gerdine. (contained in Professional Paper 41. Not issued separately.

Copper, Nabesna, and Ohisana rivers, headwaters of; scale 1:250,000; by D. (l Witherspoon. Contained in Professional Paper 41. Not issued separately.

Controller Bay region special map; scale, 1:62,500; by E. G. Hamilton. For sale at 35 cents a copy or $21 per hundred.

General map of Alaska coast region from Yakutat Bay to Prince William Sound ; scale, 1 : 1,200,000; compiled by G. C. Martin. Contamed in Bulletin 335.

Cook Inlet And Sx7Sitna Region.

The petroleum fields of the Pacific coast of Alaska, with an account of the Bering

River coal deposits, by G. C. Martin. Bulletin 250, 1905, 64 pp. Coal resources of southwestern Alaska, by R. W. Stone. In Bulletin 259, 1905,

pp. 151-171. Gold placers of Turnagain Arm, Cook Inlet, by F. H. Moffit. In Bulletin 259, 1905,

pp. 90-99. Mineral resources of the Kenai Peninsula; Gold fields of the Turnagain Arm region,

by F. H. Moffit, pp. 1-52; coal fields of the Kachemak Bay region, by R. W.

Stone, pp. 53-73. Bulletin 277, 1906, 80 pp. Preliminary statement on the Matanuska coal field, by G. C. Martin. In Bulletin

284, 1906, pp. 88-100. reconnaissance of the Matanuska coal field, Alaska, in 1905, by G. C. Martin.

Bulletin 289, 1906, 36pp. Reconnaissance in the Miitanuska and Talkeetna basins, by Sidney Paige and

Adolph Knopf. In Bulletin 314, 1907, pp. 104-125.

.1:10 Siirvkv Pi'Blioations On Alaak4

<)i>([jc roccinnaiseRnop in th MftUniixka and Talkcotna liwriiui, Alaka, hy SidoM

pBigewiil Adolph Kiiopl. Uullplii. 327. 1907, 71 pp. Nntnii (in goolmiy and minciul pmerHv-u in the vicinity ol Sowani, Kenai Peninmil

by ITS. Grant. In Bullerin 379, 1B09, pp. 98-107- Prailiminary reporl on the mineral reeourcea ol the aoulhern part of Kena) Peniawli,

by U, S. Gnint and D. F. HigginB, In Bulletin 442, 1910, pp. 166-178. Outline of the ilogy and mineral remurces of the IlianuiA ano Clark lakm rfSKm

by G. C, Martin and F. J, Kali. In Bulletin 442, 1910, pp. 179-200. (iold plftcew of Ihe MulchaOia, by F, J. Rati. In Bulletin 442. 1910. pp. 201-202. The Mount McKinky region, by A. R. Books, with deacriptJone at the ignnuil

nx'ka and of the Bonuilield and RantiHhiia districbi. by L. M. Prindle, fW

feaaional Paper 70, IBll, 234 pp.

Topiigraphie mapt.

poHion; dcolc. 1:250,0110; by R. n. namjlkm r'oft. Not published geuamtelv. inap Malauuaku and Tulkcc

T, G. Gerdine and R. U. Sargi Beparately.

lunt McKinley region; scale, l:H25,00O; by D. L. Reabiiru. feeeioual Papern 45 and 70. Not piiblislicil

m, Alanka, by G. ('. Manin nd F J. lUiieiiii trto.

Southwbsterh Ai.Aska.

n Unalaaka IsLiad, by A. J. Cuthei La ul pp. "100-101. Notes on the petroleum fields of Alaska, by G. C. Martin. In Bullet

pp. I2S-13(). Abntiaot from BulU-liii 2.W The petroleum fielda of the Pacific coast Alaska, with an account of the Bering

River coal deposits, by G. (.'. Martin. Bnlletin 250, 1905, 64 pp. Coal reeourcee of eouthwefltern Alaska, by R. W. Stone. In Bulletin 259, 1905, 1. 151-171

V coal fields, by

1 Alaska, by W. W.

/,, ,irm.

Geology and niineml res.mriv," of jiurls of Ahiskii W. W. Atwood. Bul- l.'lin4()7.

Tukok Basis.

Tbo coal resources of (be Yukon, Alaska. bv A.J. Collier, Bulletin 218, 1903, 71 pp.

15 cente- "The gold placers of the Fortymile, Birch Creek, and Fairbanks rions, bv I.. M,

Prindle. Bulletin 251, 1905. 89 pp. 3-'. cents, Yukon placer fields, by L. M. Prindle. In Bulletin 284, 1906, pp. 109-131. nn.,nnoi™.,.. f,,T, Circle to Fort Hamlin, by R. W. Stone. In Bulletin 284, 1906,

. region, Alaska; deiM-r Prindle, Bulletin 295, 27 pp. The Bonnifield and Kantishna rons, by L. M. Prindle. In Bulletin 314, 1907,

pp, The Circle precinct, Alaska, by A. H. Bro.iks, In Bulletin 314, 1907, pp. 187-204. The Yukon-Tanana region, Alaska; of the FairbankN and Rampart quadrangles, by I., M. Prindle, F, L. Hess, and C, C, Coverl, Bulletin 337, 1908, 102 pp. "Occurrence ol gold in the Yukon-Tanana region, bv I,,, M, Prindle. In Bulletin

345, 1908, pp. 179-IH6, 45 cents, *The Fortymile gold -placer district, by I., M, Prindle, In Bulletin :i45, 1908, pp. 187- 197. 45 cents.

Subvey Publications On Alaska. 331

Water-supply invefltieations in Alaska, 1906 and 1907, by F. F. Henshaw and C. C.

Covert. Water-supply Paper 218, 1908, 156 pp. . Water supply of the Fairbanks district in 1907, by C. C. Covert. In Bulletin 345,

1908, pp. 198-205. 45 cents. The Fortymile quadrangle, by L. M. Prindle. Bulletin 375, 1909, 52 pp. Water-supply investigations in Yukon-Tanana region, 1906-1908, by C. C. Covert

and C. E. Ellsworth. Water-Supply Paper 228, 1909, 108 pp. The Fairbanks gold-placer region, by L. M. Prindle and F. J. Katz. In Bulletin

379, 1909, pp. 181-200. Water supply of the Yukon-Tanana region, 1907-8, by C. C. Covert and C. E. Ellsworth. In Bulletin 379, 1909. pp. 201-228. Gold placers of the Ruby Creek district, by A. G. Maddren. In Bulletin 379, 1909,

pp. 229-233. Placers of the Gold Hill district, by A. G. Maddren. In Bulletin 379, 1909, pp. 234-

Gold placers of the Innoko district, by A. G. Maddren. In Bulletin 379, 1909,

pp. 238-266. The Innoko gold-placer district, with accounts of the central Kuskokwim Valley and

the Ruby Creek and Gold Ilill placers, by A. G. Maddren. Bulletin 410, 1910,

87 pp. Sketch of. the geology of the northeastern part of the Fairbanks quadrangle, by

L. M. Prindle. In Bulletin 442, 1910, pp. 203-209. The auriferous quartz veins of the Fairbanks district, by L. M. Prindle. In Bulletin

442, 1910, pp. 210-229. Placer mining in the Yukon-Tanana region, by C. E. Ellsworth. In Bulletin 442,

1910, pp. 230-245. Occurrence of wolframite and cassitedte in the gold placers of Deadwood Creek,

Birch Creek district, by B. L. Johnson. In BuUeUn 442, 1910, pp. 246-250. Water supply of the Yukon-Tanana region, by C. E. Ellsworth. In Bulletin 442,

1910, pp. 251-283. The Koyukuk-Chandalar gold region, by A. G. Maddren. In Bulletin 442, 1910,

pp. 284-315.

Topographic maps.

Fortymile quadrangle; scale, 1:250,000; by E. C. Barnard. For sale at 5 cents a

copy or $3 per hundred. The Fairbanks quadrangle; scale, 1:250,000; by T. G. Gerdine, D. C. Witherspoon,

and R. B. Oliver. For sale at 10 cents a copy or $6 per hundred. Rampart Quadrangle; scale, 1:250,000; by D. C, Witherspoon and R. B. Oliver.

For sale at 10 cents a copy or $6 per hundred. Fairbanks special map; scale, 1:62,500; by T. G. Gerdine and R. H.Sargent. For

sale at 10 cents a copy or $6 per hundred. Yukon-Tanana reon, reconnaissance map of; scale. 1 : 625,000; by T. G. Gerdine.

Contained in Bulletin 251, 1905. Not published separately. Fairbanks and Birch CVeek districts, reconnaissance mans of; scale, 1 : 250,000; by

T. G. Gerdine. Contained in Bulletin 251, 1905. Not issued separately, (ircle quadrangle, Yukon-Tanana region; scale, 1 : 250,000; by I). C. Witherspoon.

('ontained m Bulletin 295. For sale at 25 cents a copy.

8Ewa&D Penznsxtla.

A reconnaissance of the Cape Nome and adjacent gold fields of Seward Peninsula,

Alaska, in 1900, by A. H. Brooks, G. B. Riclmrdson, and A. J. C/collier. In a

special publication entitled "Reconnaissances in the Cape Nome and Norton

Bay regions, Alaska, in 1900," 1901, 180 pp. A reconnaissance in the Norton Bay region, Alaska, in 1900, by W. C. Mendenhall.

In a special publication entitled Reconnaissances in the Cape Nome and

Norton Bay rwons, Alaska, in 1900," 1901, 38 pp. A reconnaissance of the northwestern portion of Seward Peninsula, Alaska, by A, J.

Collier. Professional Paper 2, 1902, 70 pp. The tin deposits of the York region, Alaska, by A. J. Collier. Bulletin 229, 1904,

61 pp. Recent developments of Alaskan tin deposits, by A. J. Collier. In Bulletin 259,

1905, pp. 120-127. The Fairhaven gold placers of Seward Peninsula, by F. H. Moffit. Bulletin 247,

1905. 85 pp. The York tin rmon, by F. L. Hess. In Bulletin 284, 1906, pp. 145-157. Gold mining on Sdwazd Peninaula, by F. H. Moffit. In BuUetin 284, 1906, pp. 132-141.

838 auRVEV publications os al&ska.

The Kougarok sion, by A. H. Brtxiks. In Bulletin 314, 16+ Water supply of Nomp reon, Sw&rd Penioaulft, Alaska, 1908, by J. CiHojl

F. F. Henahaw. Water-Supply Paper 19B, 1907, 52 pp. 15 cents. Water BUpply of the Nome region, Seward Peninsula, 1906, by J. C, Hoyt and F, F,

Hi-shaw. In Bulletin 314, 1907, pp. 182-186. The Nome nwion, by F. D. Moffit. In Bulletin 314, 1907, pp. 126-14.5. Gold fields of the Solomon and Niukluk river banna, by F. 8. Smith- In Bulh

314. 1907, pp. 146-150. Geology and mincml rewmrcwi ol Iron Creek, by P. 8. Smith. In Bulletia .'114,

1907, pp. !57-lS3.

The gold placeni of \MTte of Seward Peninsula, Alaska, iQctudiim the Nome, Council, Kougarok, Port Clarence, and Goodhope precinct, bv A. J. teller, F, L. Hnu, P. S. Smith, and A. U. Brooks. Bulletin 328, 1908, '343 pp. "Invefltieation of the mineral deputdu of Seward Peninsula, by P. S. Smith. In

Bulletin 346. 1908, pp. 206-250. 45 cento. *The Sewurd Femnula tin dopoails. by Adolph Knopf. In Bulletin 345, 1908,

pp. 251-267. 45ienlj.. 'Mineral deposits of the Lost River and Brooks Mountain regioHR, Seward Peninsula,

by Adolph Knopf. In Bulletin 345, 190S, pp. 268-271. 45 cents. 'Water supply of the Nome and Kougarok regions, Seward Peninsula, in 1906-7, by F- F- Henshaw. In Bulletin 345, 1908, pp. 272-286. 45 cents. Waterupply invttieiitioiia in Alaska, 1906 and 1907, by F. F. HeoHhavr and C. C.

Covert. Water-supply Paper 218, 1908, 156 pp. Geulo of the ScA'ard Peninsula tin depiisite, by Adolph Knopf. Bulletin .'iM,

1908. 72 up.

Recent aevelopmenis in southern Seward FeniuRula, by P. 8. Smith. la Bullelin

Water-supply inveetisations in Seward Peninsula in 190S, by F. F. Benshaw.

Bulletin 379, J909, pp. 370-401. Geology and mineral resources of the Solomon and Casadepaga qnadranglee, SewHd'.

PiTiiwuia, by P, S, Smith, Bulletin 433, 1910, 227 pi, Mineral reso ureses" of the Nulato-Council region, by P. B, Smith and fl, U, Ealdn.

In Bulletin 442, 1910. pp. 316-352, Mining in Seward Peninsula, by F. F. Henshaw. In Bulletin 442, 1910, pp. 353-

371, Water-supply inveslij'ationB in Seward Peninsula in 1909, bv P. F, Henshaw, In

Bullelin 442, 1910, pp. 372-418, A geolopio reconnaissance in soulheasfern Seward Peninsula and the Norton Bay-

Nulalo rcon, by P. S. Smith anil U. M, Kakiu, Bulletin 449, 1911, 146 pp.

Tojiugriijthic mips. The following maps are fur sale at 5 cents a cnjiy or t3 per hundred: t'afludcpaga quadrangle, Seward Peninsula; wale, 1:62,500; by T. G, Gerdine. Grand Central special, Seward Peninsula; scale, l:(i2,500; bv T. G. Gerdine, Notne special, Seward Peninsula; scale, 1: 62,500; by T, G, Gerdine, Solomon quadrangle, Seward Peniiicula ; scale, 1: 62,500; by T. G. Gerdine,

The following maps are for sale at 25 cents a copy or $15 per hundred : Seward Peninsula, iiortheastern portion of, topographic roconnaisaance of; scale,

1:250,000; byT.G. Gerdine, Seward Peninsula, northwestern portion of, toiMigraphic reconnaissance of; scale,

1:250,000; by T. G, Gerdine, Seward Peninsula, sontheni portion of, tiipiphic reconnaissance cif ; scale, 1 : 250,-

000; byT.G, Gerdine, Seward Peninsula, soulheaatern jwrtion of, topographic recoiinaiHsance of; scale,

I :250,000. Contained in Bulletin 449, Not tJejiarulely.

Northern Alabka.

A reconnaissance from Fort Hamlin Kanuti, Allen, and Kowak riven 1902, 68 pp.

Survey Publications On Alaska. 383

reconnaissance in northern Alaska across the Rocky Mountains, alone the Koyukuk, John, Anaktuvuk, and Colville rivers, and the Arctic coast to Cape Lisbumb, in 1901, by F. C. Schrader and W. J. Peters. Professional Paper 20, 1904, 139 pp.

Coal fields of the Cape Lisbume region, by A. J. Collier. In Bulletin 259, 1900, pp. 172-185.

Geology and coal resources of Cape Lisbume region, Alaska, by A. J. Collier. Bulletin 278, 1906, 54 pp.

Topographic maps.

Fort Yukon to Kotzebue Sound, reconnaissance map of; scale, 1: 1,200,000; by D. L. Reaburn. Contained in Professional Paper 10. Not published separately. *Koyukuk River to mouth of Colville River, including John Kiver; scale, 1: 1,200,000; by W. J. Peters. Contained in Professional Paper 20. Not published separately.

Department Of The Interior United States Geological Survey

HEORGB OTIS SMITH, BOLLKTrW 481

Results Of Spirit Leveling In California

1907 To 1910, Inclusive

R. B. MARSHALL, Chief Geographer

Washington

Qoveknhent Printing Office 19H

Contents.

Page. Introduction 5

Corrections 5

Personnel 7

Classification 7

Bench marks 7

Datum 8

Topographic maps 8

Precise leveling 11

Antioch, Courtland, Davisville, and Fairoaks 15 quadrangles; Bouldin, Isleton, Jersey, and Rio Vista quadrangles (Sacramento, Solano, and

Yolo counties) 11

Primary leveling 16

Fairoaks W quadrangle; American, Antelope, Arcade, Brighton, Clarksville, Folsom, Mills, and Scott Ranch 7y quadrangles (Placer and Sacramento counties) 16

Courtland 15 quadrangle; Bouldin, Isleton, Jersey, and Rio Vista 7Y quadrangles (Contra Costa, Sacramento, San Joaquin, Solano, and Yolo counties) 19

Jackson and Lodi quadrangles (Amador, Sacramento, and San Joaquin counties) 21

Byron and Tracy 15 quadrangles; Holt, Lathrop, Stockton, and Union Island 7y quadrangles (Alameda, Contra Costa, San Joaquin, and Stanislaus counties) 24

Dunnigan 15 quadrangle; Knights Landing, Lincoln, Marcuse, Nicolaus, Pleasant Grove, Rocklin, Roseville, Sheridan, and Vernon 7Y quadrangles (Colusa, Placer, Sutter, and Yolo counties) 29

Browns Valley, Gillsizer Slough, Grimes, Marysville Butte, Meridian, Ostrom, Smartsville, Spencerville, Sutter, Tisdale Weir, Wlieatland, and Yuba City quadrangles, and Smartsville special quadrangle (Colusa, Nevada, Sutter, and Yuba counties) 35

Bangor 15' quadrangle; Biggs, Butte City, Butte Creek, Cherokee, Clear Creek, Dayton, Dry Creek, Durham, French Crossing, Gridley, Honcut, KeefeiB, Nelson, Newhard, Nord, Oroville, Palermo, and Pennington 7y quadrangles (Butt-e, Colusa, Glenn, Sutter, and Yuba counties) 41

Etna Mills, Hoopa, Preston, Sawyer Bar, Seiad, and Yreka quadrangles (Humboldt and Siskiyou counties) 56

Capitola, Morgan Hill, New Almaden, Pajaro, Point Sur, Salinas, San Jose, and Santa Cruz quadrangles (Alameda, Monterey, San Mateo, Santa Clara, and Santa Cruz counties) ft5

C-ape San Martin, Paraiso Springs, Priest Valley, and San Miguel quadrangles, and Gonzales 15' quadrangle (Kern, Kings, Monterey, and San Luis Obispo counties) 71

Contents.

I Primary Weliii— Coniinued.

ConliD and Panoche W quadrangle*; Tracy 16' quBdrangle; Copperopolia,

Crows Landing, Uolt, Ingomar, Loc Bonce, Newman, Peteis, Stockloii.

VoltA, and Weelley 7)' quadranglee (Freno, Pierced, San Joftquin, and

Stanielaiw rountiea) 81

Bakenfield, CaJieate, Cholame, HusHiia, McKitUick, LoetHilla, and Tejon

quadnuigle(£em, Kings, and San LuieUbiepocouuliea) SK

Freeno, Maripoea, and Merited SC quadmlee (Freeno, Hadera, Mariposa..

and Merced counliee) 95

Bridgeporl, Hawthorne, and Mount Lyell<]uadranglet< (Mono and Tualumnu

counlieu) 102

Cracero and Ivanpah 1° quadranglep (San Bernardino County) IQb

Hantord 30' quadrangle (Kings CoJinty) lOS

dex lU

Platb I..leoU>(cal Survey nirk> 5

Results Of Spirit Leveling In California, 1907

To 1910, Inclusive.

R. B. Marshall, Chief Geographer.

Introduction.

The following results of spirit leveling are supplemental to and accord with the elevations contained in Bulletin 342. Corrections to Bulletin 342 should be noted as follows:

Page 13, Fairfield ; bench mark was moved in 1911 ; present elevation not known.

Page 23, Chandler, add the foUowing-deecribed bench mark: Chandler, 0.1 mile south of, on east side of railroad, opposite milepost 106, 6 feet from track; iron post stamped *'36 B 1902;" elevation, 36.227 feet.

Page 80, change descripticm of first bench mark to read: T. 10 N., R. 19 W., near northwest comer of sec. 4, just south of point where cutoff road to Bakersfield turns west, near telephone pole 1368, 12 feet south of gate across road, 10 feet east of center of road, 2 feet south of post 6 by 8 inches; iron post stamped ''1085 L. A.;'' elevation, l,08i6.919 feet.

Page 81, Santa Barbara; bench mark has been reestablished at northeast side of city hall, 8.5 feet southeast of northeast comer, iron post stamped "37 L. A.;" elevation, 38.007 feet.

Page 81, Santa Barbara, a new bench mark has been established, the description being as follows: Santa Barbara, city bench mark, comer De La Guerra and Anacopa streets (city elevation 32.545); U. S. G. S. elevation, 36.222 feet. Page 85, Casmalia; bench mark described has been destroyed.

Page 100, the following should be added to the Bishop quadrangle: Laws, 6.5 miles west of, north of road, 0. 5 mile west of canal; iron post stamped "4356;" elevation, 4,355.603 feet.

Page 108, Coalinga; bench mark has been moved but its elevation not materially changed.

Page 112, Fresno quadrangle; a portion of the elevations in this quadrangle have been readjusted, the corrected elevations being given in this supplement, pages 95-96.

Page 113, Kaiser quadrangle; the elevations of bench marks on this page are subject to a correction of —0.6 feet.

Page 114, the elevations of bench marks in the Kaiser quadrangle listed on this page have been changed to read as follows:

Bear Meadow, 0.5 mile northwest of, south of trail, gn summit west of Bear Feet. Meadow, in granite ledge; bronze tablet stamped '*7554 F 7, 561. 109

Caanidy Meadow, south side of Rattlesnake Lake, sec. 24, T. 5 S., R. 23 E., east of granite point, in ledge between trail and lake; bronze tablet 5,582.819

6 SPrRIT LEVELING IN CALIFORNIA. IBOT TO 1010.

ToUhODK KhDOUioaM neitkwtit Uosf pobUs load td powar booM, thtaM ftlOBC

plpa Uns to mairolr. thantw aloni ditch to polst nllBi toothaut of Xotik Fork. T, 10 S., R. 23 E.. sef, S, -nulh nf Lnlfrwctiou of Pini.- Ridge and power

house roads, in of granite ledge; bronie tablet a camped "2013 F" 2,008. 711

Stm Joaquin, eec. IS, T. 9 S., R. 23 E., light aiid power house, at Doneast

corner of building, iu gnmite pillar; bronie tablet tani|>ed "1013 F" 1,008,528

North Fork, sec. 30, T. 8 S., R. 23 E., 2 miles 8oulhea*l ot post office, weet

of mad and dilch, at sharp curve above field and house, in granite bowlder

10 by 8 feet; bronze tablet alauiped '2503 F " 2, 49S.C88

Pages 117, lis. 119, Bridgeport and Mount Lyell quadrangles; the elevations on these pages, benning with the Bridgeport quadtSiiigle, have had a coireclioit of approximately +4.0 feet made lo them. The corrected elevations are published in this supplement, pes 102-105.

Page 127, the elevations of bench marks in the New Almadec and Santa Cruz quadnnglea have been changed slightly by readjustment, and the correct elevations are published in this supplement, pages 60. 67.

Page 139, Antioch quadrangle; clevatiune of the following bench marks have been changed slightly by a readjmtment, and are now accepted ae follows: Fairfield courthouse. 2.8 miles eaet of. 100 feet oast of water tank, on south Feet.

side of toad; iron poet etampted "15 B" 14.670

T. 5N,, R. 1 W .southeast corner of sec. 29. 35 feel north of culvert, on eaat

aide of road to north of junction; iron po&t stamped " 15 6 " (set in 1S06)-. 14. 754 Denverton, 5 feet west of northwest comer of blacksmith shop, in front of

BchoolhoU8e;ironpoatHtamped"7 B" 6,618

Page 140, elevations of the following-deecribed bench marks are iiow acceplad u follows: MonteBuma schoolhouse, southeast comer of yard, west ot road; imm poet fm.

stamped "41 B " 41. 201

Willow Springs schoolhouse, soulbeaat comer of yard, weet side of road;

iron poet stamped " 58 B " 57, 738

Tolande Landing, 3 miles west of, north side of road, 1 foot south of fence

line, 8 feet east of gate, 0.2 mile west of feeding shed, 100 feet north of

enough; iron post stamped "10 B" 9.998

CoHinsville, 0.5 mile north of, southwest comer of schoolhouse, at croee-

roads; iron post stamped "5 B" 4.968

Page 142, Fairoaks quadrangle; the elevations of several of the bench marks in this quadrangle have been changed slightly. The descriptions and corrected elevations are given in this publication, pages 15-17.

Page 151, Greenwood; the elevation of this bench mark has been changed to read "198,472,"

Page 152, Squaw Hill Ferry, the elevation of this bench mark has been changed to read "196,162" The elevation of United States Corps of Engineers bench mark No. 6 is 198.273 feet.

Page 153, Coming; the elevation of this bench mark has been changed by a new adjustment to read "303.335. "

Pages 153 and 154. elevationsof the following bench marks in the Tehama quadrangle have been changed by a new adjustment as follows:

Red Bluff, 6.5 miles south of, west side of road, 3 feet south of telephone Feet.

pole; iron post stamped "311 B" 310.302

Red Bluff, 10.5 miles south of, west side ot road, 4 feet north of telephone

pole; iron post stamped "304 B" 303.349

Tehama, 5.5 miles weHt of, west side of road. Bed Uluff at crossroads, 5 feet

north ot telephone pole; iron post stamped "308 B " 307, 063

Cone estate, Antelope ranch headquarters, beside walk in front of residence,

east side of road; iron post sUmped "271 B " 270. B4

Personnd. — The field work for 1907 was done irnder R. B. Marshalli geographer, and the later work under T. G. Gerdine, geographer, under the general direction of R. B. Marshall, chief geographer. The names of the various levelmen are given in the introduction to each list. The office work of computation, adjustment, and preparation of lists was done mainly by S. S. Gannett, geographer, and D. H. Baldwin, topographer, and since 1907 under the general direction of E. M. Douglas, geographer.

ClcLSsiJication. — The elevations are classified as precise or primary according to the methods employed in their determination. For precise-level lines instruments and rods of the highest grade are used, each line is run both forward and backward, and every precaution is taken to guard against. error. The allowable divergence between the forward and the backward lines in feet is represented by the

formula 0.0 1 7 -/D, in which D is the distance in miles between bench marks. For primary lines standard Y levels are used; lines are run in circuits or are closed on precise lines, with an allowable closing

error in feet represented by 0.05 VD, in which D is the length of the circuit in miles, sufficient care being given to the work to maintain this standard. For levels of both classes careful office adjustments are made, the small outstanding errors being distributed over the lines.

Bench marks, — The standard bench marks are of two forms. The first form is a circular bronze or aluminum tablet (0 and E, PI. I), inches in diameter and one-quarter inch thick, having a 3-inch stem, which is cemented in a drill hole in solid rock in the wall of some public building, a bridge abutment, or other substantial masonry structure. The second form (F, PL I), used where masonry or rock is not available, consists of a hollow wrought-iron post inches in outer diameter and 4 feet in length. The bottom is spread out to a width of 10 inches in order to give a firm bearing on the earth. A bronze or aluminum-bronze cap is riveted over the top of the post which is set about 3 feet in the ground. A third style of bench mark with abbreviated lettering (B and D, PI. I), is used for unimportant points. This consists of a special copper nail IJ inches in length driven through a copper washer seven-eighths inch in diameter. The tablets as well as the caps on the iron posts are appropriately lettered, and cooperation by States is indicated by the addition of the State name (G, PI. I).

The numbers stamped on the bench marks described in the following pages represent the elevations to the nearest foot as determined by the levelman. These numbers are stamped with three-sixteenthinch steel dies on the tablets or post caps, to the left of the word "feet." The office adjustment of the notes and the reduction to

B SPIRIT LEVEl-ISO IN CAIJFOSNIA, 1907 TO 1010.

mean icii level datuiu inay so cliange some of the fibres that the original markings are 1 or 2 feet in prior. It in assumed that pngincore ftrid olliers who have occasion to usp the heiich-mark elevations will apply to the Director of the United States Geologieal Survey, at Washington, D. ('., forth adjusted values, and will use the markings as identification numliers only.

Thituin. — All United States Geological Survey elevations are re- . fcni'i! Ill mean sea level, which is the level that the sea would assume if 1 1ll- iiilliience of winds and tides were eliminated. This level is not tile elevation determined from the mean of the highest and tha lowest tides, nor is it the half sum of the mean of all the high tides and the mean of all the low tides, whicli is called the half-tide lev. Mean am ia the aeemge height of thf- yfcr, oH fges of Hie heing coitsvlered. It is determined from obseirations made by meai of tidal gages placed at stations where local conditions, such as lonl narrow hays, rivers, and like features, will not affect the iieight of the water. To obtain even approximately correct results these obaer ( vations must extend over at least one lunar month, and if accuracy J is desired they must extend over several years. At ocean stations t tlin half-tide level and the mean sea level usually differ but little, Ifc is assumed that there is no difference between the mean sea level t determined from observations in the Atlantic Ocean, the Gulf of* Mexico, or the Pacific Ocean.

The connection with tidal stations for bench marks in certain areas tliat lie at some distance from the seacoast is still uncertaiij, and this fact is indicated by the addition of a letter or word to the right of the word "datum" on tablets or posts. For such areas corrections for published results will be made from time to time as the preciselevel lines of the I'nited States Geological Survey or other Government organizations are extended.

Topograpliic nmyw. — Maps of the following quadrangles wholly or partly in California have been published by the United States Geological Survey up to June 10, Iflll. may be obtaijied (except as noted) for .5 cent.s each or a hundred, on application to the Director of the Survey at Washington, D. V. Alturas. ' Kakorsficlil niwHal.

Ainawi'"''?Kii'"(-''<'*'-''al.).' -i ISccuIh). , lUlliinU (ral.-Ncv.l.-' Anuheim. lUitii.T Itill xixrial.

Aiitioch. ! HJiU-dl liar.

Amiyii (.iraiuli-.* I ItinTrtT.f.

Out of print.

Kanidi sheet nnil lurlflol FiinincT' Crook, nnd I.Ida sIiMli.

Anahrtm .Sanln .Vrui vlitl-, uii V'uli'uri:ii:;..''ii, huvc lni'ii ,in'\ form pnrta ol Corona ,

Intboduction.

Bouldin.

Bruce ville.*

Calabasas.

Camp Mohave (Ariz.-Nev.-Cal.).

Camulos.

Capistrano.

Carbondale.*

Carquinez.'

Caetle.i

Cayucos.*

Chico.

Clements.*

Colfax.

Colusa.

Concord.

Corona.*

Coeumnes.*

Courtland.

Cucamonga.

Cuyamaca.*

Dardanelles.

Davifiville.

Deep Creek.

Downey.

Downieville.

Dimnigan.

Elcajon.®

Elk Grove.

Elsinore.®

Escondido.'

Fairoaks!*"

Fernando.

Florin.

Furnace Creek (Cal.-Nev.)."

Galt.i

General Grant and Sequoia national parks.*'

Genesee special.

Goleta special.

Goose Creek.*

Grass Valley special.

Guadalupe.

Hawthorne.

Haywards.

Headreach.*

Hesperia.

Holtville.

Honey Lake.

Hueneme.

Indian Valley special.

Indio special.

Isleton.

Jackson.

Jersey.

Kaiser.

Kaweah.*'

Kawich."

Kemville.

Knights Landing.

La Jolla.

Lake Tahoe and vicinity (Cal.-Nev.).**

(20 cents). Las Bolsas.

Las Vegas (Nev.-Cal.). Lassen Peak. Lida (Nev.-Cal.).** Lincoln. Linden.*

I Bniceville, Castle, Clay, ClemenU, Cosumnes, Elk Orove, Florin, Gait, Goose Creek, Headreaoh, Linden, Lockeford, New Hope, Waterloo, and Woodbridge sheets show Lodi quadrangle on larger scale.

s Calabasas and Santa Susana sheets, on scale of 1:62,500, have been reduced and form parts of Camutos sheet, on scale of 1:12.'),000.

Carquinez sheet, on scale of 1:02,500, has been reduced and forms part of Napa sheet, on scale of 1:125,000.

Arroyo Grande, Cayucos, Port Harford, and San Luis Obispo sheets, on scale of 1:62,500, have been reduced and form parts of San Luis sheet, on scale of 1:125,000.

6 Anaheim and Santa Ana sheets, on scale of 1:62,600, have been reduced and form part of Corona sheet, on scale 1:125,000.

Rlcajon sheet, on scale of 1:62,500, has been reduced and forms part of Cuyamaca sheet, on scale of 1:125,000.

7 Yosemite National Park map includes Yosemite and Mount Lyell sheets and part of Dardanelles sheet, together with that part of the park not shown on those three sheets.

Riverside sheet, on scale of 1:62..500, has been reduced and forms part of Elsinore sheet, on scale of 1:125.000.

Escondido and Oceanside sheets, on scale of 1:62,500, have been reduced and form parts of San Luis Rey sheet, on scale of 1:125,000.

M Fairoaks, Lincoln, Pleasant Grove, Roseville, and Sheridan sheets show parts of Sacramento quadrangle on larger scales.

II Amargosa region map includes Kawlch sheet and patta of Ballarat, Furnace Creek, and Llda sheets. Sequoia and General Grant national parks map is a combination of parts of Tehipite and Kaweah

diets on same scale, u Out of print. M Lake Tahoe and vicinity map includes Ovson, ICarUeeville, Pyrunid Peak, and Trackee slheeta.

Bio (iPIUIT LEVEUSG

N Oalifobsia. Iimi" To 1010,

LtK-ki'tord.'

Lompoi-.

Lm Angeles (duubli? ithiei-lU cents

'

Hucuae.

Maxwell.

Koik Creek.

Modoc Uto 11-<1.

nosevillc'

Mother Ix-dedwiriclupccUlllwoshe centei.

Sacramento.'

Saiton Sink (phoWilithogmph).

Mount Diablo,

San Antonio.

Mount UamiJtun.

Mount Lydl.'

San Diego.

Mount Piuoa.

San Francisco.

Mount Wliitney.

Sail Gorgon io.

San Jacinto,

Sau Juee.

Nevada City Bpeciul.

San Luis.*

New Hope.'

San Luis ObiEpo.*

San Luia Rfy.'

Oceaiwide,*

Sun Mateo.

Oil Center Bpecbl (2 duiible sheets-M

Sbu Pedro.

centa).

Santa Ana."

Olancha.

Santa Barbara special. j

Pklo AlW.'

Parker (Ariz.-Cal.).

Sanla Panla.

Santii Susana,"

Pleasant Grove'

SanU Ynez.

Pleaainion.

Sequoia and General Grant national

Pomona.

parka."

Ponnarforri."

Sliasl!!.''

Pyramid P-nk '

RBmimii.

' BnicevlllB, Carbondale, Casllf, Ciay. C

Headrouch, Linden, Loekeloril. New Hopf

Waterloo, and WoodhrldKe slieeta show Lodi quadrangle ou

larger Kale.

' Los .V neelf s map Indiiiies PaaaJena and Santa Monica sbl3.

Lake Tahoe and vlcinily map infludnit

arson. Mnrkleevllle, pyramid Peak, and Tnlckee sheets.

Yosemlle National I'ark map fncluJM Y

toeethw with that pari ol Ihe park not alion

nonthosethreeslieeu.

' C'jirqnlnei sbeet. on Kale of 1 jyism. has b

een rediifCl and lotins pari of Napa sheet, on scale of 1:125000.

Escoodldoand OcMn9ide3his,onsrale

ol 1 ;02S00, have (wen reduced and torn parts of San Loula Re>-

t,oi.u1eotl:12awo.

' I'alo Alio slit, on scale of l:25on. has

Falroalta. Lincoln, I'lea.'anl ((rove, liose

llle.and Sheridan sheetsshou- parts olSacramenW quadrangle

Arroyo Orandc, Cayiicos. I'orl lUrford

and San Luis Ohispo nheeis, on scale ol 1:02500, have been

reduced and form parts ol San Li.ls . o

Redding and Tehama Bheets s1io- pan

of Ited [lliifT quadrangle on career scale.

II Riverslilde sheel, on scale of l:b!aOli, li

13 Iwen reduced and forms pan of Elslnore sheet, on scale ol

l:l3Xm.

11 Anaheim and Santa Ana sheets, on seal

of 1:629110, have heen redui-ed and form parts of Conia alert.

"Calabasas and Santa Snaaoa sheets, on

wale of LC2,inil. have lieen reduced and tori pans ol CalniilM

ks map l.H a lomlilnallon of parts of Teblplte and Kawoli

iTsiTirjkl I'heel show, part of Shas

a quad

ngle on larger scuh-.

Pbboise Leveuko.

Sienaville.

Silver Peak (Nev.-Cal.).

Smartsville.

Sonora.

Southern California, sheet No. 1 (double

eheet-lO cents). Southern Galifomia, sheet No. 2 (double

sheet-lO cents). Southern California, sheet No. 3 (double

sheet-10 cents). Tamalpaifi. Taylors ville special. Tehama.* Tehipite.2 Tejon. Tesla.

Truckee.'

Tujunga.

Ventura.

Vernon.

Vina.

Waterloo.*

Wellington (Cal.-Nev.).

Wheatland.

Willows.

Woodbridge.*

Woodland.

Yosemite.*,'

Yosemite National Park (25 cents).*

Yosemite Valley map (10 cents).

Yuma (Cal.-Ariz.).

PRECISE liEVELING.

Antioch, Courtland, DavtsvUle, and Fairoaks 16 quadnngleB ; Bouldin, Islekon.

Jersey, and Bio Vista iy quadrangles.

Sacramento, Solano, And Yolo Countibs.

The following are the results of a precise level line run in 1907 and 1908 by L. F. Biggs from Sacramento down the Sacramento River to Fairfield; tying to bench marks previously established near those places.

The work was done in cooperation with the State.

FAZKOAKS QUADBAHOLS. ▲t SaoraBwnto, Oapltol to poit -oIBm.

Sacramento, 300 feet east of Capitol, in top of meridian stone; aluminum Feet.

tablet stamped *'21 B*' 20.866

Sacramento, poet office building, north wall, 5 feet above groimd, 15 feet

east of northwest comer; aluminum tablet stamped 31 B 1905 30. 527

DAVISVILLE QUADBAHOLS. Baoramento south alone weit bank of Saeramento Blver.

Sacramento, United States Weather Bureau gage at comer of Southern

Pacific freight shed, foot of L Street; nail in notch of 30-foot mark 29. 510

L Street gage zero (below sea level) —0. 481

United States gage zero (below sea level) —0. 507

Southern Pacific gage zero (below sea level) —4. 861

1 Redding and Tehama sheets show parts of Red Bluff quadrangle on larger scale.

Sequoia and General Grant national parks map is a combination of parts of Tehipite and Kaweah sheets on same scale.

Lake Tahoe and vicinity map includes Carson, ICarkleeyiUe, Pyramid Peak, and Truckee sheets. Bmoerille, Carbondale, Castle, Clay, Clements, CosumneB, Elk Grove, Florin, Gait, Goose Creek,

Headreach, Linden, New Hope, Waterloo, and Woodbridge sheets show Lodi quadrangle on larger scale.

Yosemite Valley map shows part of Yosemite quadrangle oo larger scale.

Yosemite National Park map Inchides Yosemite and Mount Lyell sheets and part of Dardanelles sheets lofsthsr with that part of the park not shown oo those three ibaeta.

18 apnuT LBVBLuni m caufosvu, isot to 1910.

PW So, 22, Yolo County. 1 niiU- onrthwml rd nrodrnr-k, an pcapertr nf ValPDti&p HkUMf, aiO f4 irmt ni h-vw. 500 (wH wwa of Biver. un line ul w ire touch ruautng rn and veM between two pastures: Fnt.

KlumimtiD Ublrt in top of lifor i

Plar N, 22; cnpin-r b-ili in bow ]

BraderidcS.OinilMwiuthut, wast side . in front o( bopUnng bnw on FkrvjihrT-: inwi pint atuniptd "B29 IMS P I" 2&071 i

Her Xo. 20. Yui'> County. 5 nitiM soutbwMl of Broderick. on pmperty nt 'ISulina U. riruhler. in romer tt fence, 230 (m BcnilheasI of hnme. fiOn let wen of Sacramenlo River leve*: tablet in lop of pier I

Kcr No. 2ft; copper Imlt in baep 16. DM

Rivriviilp, oppoeile. 300 feel aoulh of Uachanlfe'a hour, 20 feel Bonth of

rod; iron poet 8tanipf "22 B 1905 F 2" i

BBoaasBto Math aknt Mat task ot Sunarata Bti.

Pier No, 21. Sacniniento County, in oulakirts of Sacramento, on pwperty of W. W. Burler, in norlhweat coRier oi hop yaixlweet of and adjoining Riverside Road, 30 feet Ixan ievee on cast side of Sacntnenlo River, eOO feet west from saloon of E. H. Hoppe, 0.25 mile norDiwen nf end of eletric car line, 0.5 mile aouili of Odd Fellowa' Cemetery; aluroinum tablet in top of pier 21. 177

Pier No. 21; copper boh in base I

Sactamento, Southern P&dfic Railroad bench mark, in base of tive at railroad croasinif; spike 1

Pir No. 19, Sacrameitto Cotmty, 4 milee north of Freepnt and 125 miles below brickyard on left bank of Sacramento River, on prupaiy of Joe Tash, 225 feet east of leve on eoitlb aide of private road leAdin;; fmm county road to house of Joe Taah, 126 feet northeast of bam, 300 feet southwest of windmill, and 720 feet southwest of junction of county and private mad: aluminum tablet In top of pier 17.806

PirNn. 1!>; cop] w bolt in base 14.128

QITADKASQLE. Point * Gno CIsb loiitb giant weit bank of Bkcnunento BInr.

Glide Gun Club, 0.5 mile south of, on fence Hue between (ilidoaiid Content, 300 feet south of Manuel (.'onlent.'s house, l.iO feet west of levee, 20 feet smith of southwest comer of woodhouee; iron post stamped "16 B 1905

Pier No. 18, Yolo County, 1 .5 miles west of Freeport, on property of Lizzie H. Glide, near oak tree by fence on east aide of properly, 375 feet south of Bohoolhoiise ndjoinin); levee on riht bank of river, and 0.25 mile east fMm wharf and group of buildings belonging to Lizzie II. Glide; aluminum tablet in top of pier 15. 879

Pier No. 18; copper bolt in base 12, 261

Freeport, 0.5 mile north of Anton Fenian do's house, 40 feet from northeast comer o(, west side of road, northeast comer of house lot; iron post Stamped "21 B 1905 F4" 20,852

Clarksburg, 0.5 mile north of, 100 feet east of Merritt sehoolhouse, inside fence; iron post stamped "14 B 1305 F 5" 14.263

Pier No. 16, Yolo County, in town of Clarksburg, on property of Ella P. \V. Smith, ill south corner of pear orchard inclosed by wire fence, 37,'> feet Boillliwpst of Ella P. W, Smith's house adjoining Icvee on cast side of orchanl. feet south of sehoolhouse, 1 .000 feet northwest of store anil post ollicc managed by Cave db Co. ; aluminum tablet in tup o( pier 13. 429

Precise Leveling. 13

Feet.

Pier No. 16; copper bolt in base 9. 785

Clarksburg, gage zero below sea level —4. 382

(Note. — The foot graduations above 20-foot mark are numbered I foot too great; thus, 21 is numbered 22.)

Clarksburg; 2.2 miles south of, 40 feet south of Ross's house, 200 feet west of Sacramento River; iron post stamped "19-1906 B N " 19. 606

Courtland, 2.0 miles north of, 20 feet east of road, 150 feet west of drainage corral, 260 feet north of levee; iron post stamped 10 1906 B N" 9. 900

Pier No. 14; Yolo County, 1 mile north of Courtland, on property owned by J. L. McFadden, in southwest comer of pasture inclosed by wire fence, 750 feet west of J. L. McFadden's house, 400 feet west of bam, which is 480 feet southwest of house (both buildings adjoin levee); aluminum tablet in top of pier 1 1. 028

Pier No. 14; copper bolt in base 7. 354

Grand Island, north comer of bridge abutment; aluminum tablet stamped

1906N" 19.696

Pier No. 12, Sacrament) County, Grand Island, on property of Isaac G. Hall, 0.5 mile south of Vorden, on fence line on south edge of orchard, 10 feet north of road running west from levee, 160 feet west of large frame house owned by California Transportation Co., in southeast comer of orchard at junction of road and levee, 0.25 mile south of pumping station on west bank of river; aluminum tablet in top of pier 10. 337

Pier No. 12; copper bolt in base 6. 723

Point near LUbon lohool south alone oait bank of Saeramento Rtver.

Freeport Ferry, in front of ferryman's house, north side of road, in top of

hitchiag post; nail 27. 832

Pier No. 17, Sacramento County, 1.5 miles south of Freeport, on property of J. H. Beach, at southeast comer of storehouse, 450 feet south of vertex of angle formed by junction of railroad grade with levee, 75 feet north of house and 200 feet west of bam of J. H. Beach, 35 feet north of private road from levee through property of J. H. Beach, 125 feet northeast of

junction of private road with levee; aluminum tablet in top of pier .16. 301

Pier No. 17 ; copper bolt in base 12. 583

Pier No. 15, Sacramento County, 4 miles northeast of Courtland, on property of the William Johnston estate, situated in south comer of inclosure south of and adjoining house, 200 feet south of house, 100 feet southwest of windmill, 240 feet northwest of creamery, and 185 feet from intersection

of fence with levee; aluminum tablet in top of pier 12. 793

Pier No. 15; copper bolt in base 9. 078

Courtland; gage zero (below sea level) —4. 501

Courtland, south wall of Bauer, Miller & Newbert's store; aluminum

tablet stamped *'14 B 1906 N " 13. 755

Pier No. 13, Sacramento County, in town of Paintersville, on property owned by Maggie V. Painter, 2 miles south of Courtland, 3 feet from south side of high board fence of corral, 30 feet east of two large oak trees standing 20 feet apart, 300 feet southeast of house of Maggie V. Painter, 140 feet east of bam on east side of levee below house, 200 feet

from levee; aluminum tablet in top of pier 10. 101

Pier No. 13; copper bolt in base 6. 402

Vorden; gage zero (below sea level) —5. 252

lj.4 SPIRIT LEVELING IN CAUFOBNIA, UN37 TO lUlO.

GrsDcl lalsnd, i miles south of bridge, 250 feet mutheaet of E, B. Kinft'it hoiiso. 150 feel Qoitheadt of SacraniPntfl River levee, 100 feet uortheost of F(.

croBB levee; iron poet stamped "8 01906 N " 7, 51

Grand leland Bridge, about 4.1 milee aautheast of, 0.9 mile east of E. B, King's house, in base of spike (Sacramento Southern R. R. bench mark) 12.458

BOinJlIK. T8LZT0R, ncBSXT, jUTD UO TI8TA Tf QIIASRAKaLBS. PalBt MU iDiitliweit titus eonlimit iicla ol SuraiaaBto Blm.

Pier No. 10, Sacranienio County, in (own of Ryde, on property of W. A. Kesner, 250 feet weat of levee in northwest comer of alfalfa patch adjoining levee, 375 feet iiorthwent of W, A . Keener's house, 750 feet north of pumping station on south aide of road near junction with levee; aluminum tablet in top of pier 7, 356

Pier No. 10; copper bolt in baee 3. 7fil

Rydo; gage aero (below sea level! —4. fi2a

Ryde, watr gage, west end of pier; lo-foot mark 10.374

Pier No. 9, Sacramento County, Andrus Island, on property of Jane Smith, i milee north of Isleton, al edge of open space in orchard on wire fence line, 150 feet east of intersectioD of leveie with said wire fence which marka boundary between propertyof Jane Smith and George Nelson, I,0O0 feet soutbeaet of house of Jane Smith and 0.5 mile west of pumping

station on Georgiana Slough ; aluminum tablet in tap at pier 8. 9G&

Pier No. 11; copper bolt in base 5.246

Pier No. 8, Sacramento County, on Grand Island, on properly of Stem A Co., 0.6 mile northeast of Isleton, near end of row of poplar trees running J

north from Ipvpo, 280 fpet from jiincMoii of said row and levee, 1,000 feet northwest of house, near dividing line between property of Mrs. Buckley

and that of Stem & Co. ; aluminum tablet in top of pier 5. 847

Pier No. 8; copper bolt in base 2.253

Rio Vista, 1.9 miles north of, 100 feet east of saloon, near ferry landing, 60 feet west of river, east side of road, in top of 6 by 6 inch timber; nail. ... 9. 269

Rio Vista, ferry; gage zero (below sea level) —4. 403

Rio Vista, water gage; spike in 16.4 fool mark 12.361

Rio Vista; gage zero (below sea level) —4.039

Rio Vista, southeast comer of bank building, 2 feet above sidewalk; altmii-

num tablet stamped "23 B 1905 F IT" 22.425

Pier No. 6, Solano County, 0.3 mile south of Rio Vista, 0.3 mile west of Houthem end of Wood Island, just above edge of swamp in river bottom;

Ublot in top of pier 28. 849

Pier No. 6; copper bolt in base 25.158

Rio Vista, 3,5 miles southwest of, 100 feet from southwest comer of Madison's blacksmith shop, north comer of field, east side of road; iron post stamped " B 54 1907 F 20" 53. 822

Point naai Qion lODtbwaat along lontbe&il ilde of Sunmenta .

Pier No. 11, Sacramento County, in town of Walnut Grove, on property of Mary L. Wise, 0.5 mile north of post office; near fence on southwest side of corral surrounding bam, in line with short row of fruit trees mnning northeast from levee, 250 feel northeast of house near le\'eo, 400 feet east of large oak tree on river bank, marking comer in north boundary of property of Marj- L. Wise; aluminum tablet in top of pier 8.214

pier No. 11; copper bolt in base - 4.692

Pbimaby Leveling. 15

Feet.

Walnut Grove; gage zero (below sea level) —1. 3W

Georgiana Slough; gage zero (below sea level) —5. 829

Isleton; gage zero (below sea level) —4. 647

Ida Island, south of east end of G. F. Terschman's house, 85 feet west of,

200 feet south of Sacramento River; iron post stamped "5 B 1906 N " 4. 943

Pier No. 7, Sacramento County, on Brannan Island, on property of J. Desroeier, 2 miles west of Isleton, and 0.25 mile above Rio Vista Ferry, in northeast comer of orchard, 275 feet south of levee, 225 feet south of

house, 110 feet southeast of bam; aluminum tablet in top of pier 6. 245

Pier No. 7 ; copper bolt in base 2. 561

ANTIOCH QUADRANGLE. Tolandi TjftwiUng alone northeast bank of Baonunento Rtver.

Tolands Landing, summit of Blue Gum Hill, pier 4 ; aluminum tablet in top 119. 528

Tolands Landing, summit of Blue Gum Hill, pier 4; bolt in base 115. 838

Tolands landing; 12-foot mark, United States water gage 8. 292

Tolands Landing; 12-foot mark, California water gage 6. 529

Stratton ranch, summit of small hill, pier 2; aluminum tablet in top 37. 928

Stratton ranch, summit of small hill, pier 2; bolt in base 34. 198

Collinsville; 12-foot mark. United States water gage 4. 591

Collinsville; 10-foot mark, California water gage 5. 508

PRIMARY liEVEIilNG.

Vairoaks 16 quadiancle ; American, Antelope, Arcade, Brighton, ClarksvUIe, Folsom,

Hills, and Scott Banch ly quadrangles.

Placer And Sacramento Counties.

The elevations in the following list are based on the results of precise leveling along the Southern Pacific Railroad, published in Bulletin 342. Readjusted elevations are given for bench marks in the Fairoaks quadrangle.

The leveling in the Fairoaks quadrangle was done in 1901 by L. D. Ryus and in 1908 by L. F. Biggs and B. A. Jenkins, that in the American, Clarksville, Folsom, and Scott Ranch quadrangles was done in 1908 by Biggs and Jenkins. The State cooperated in the work.

FAIROAKS 16' QUADRANGLE, INCLUDINa ANTELOPE, ARCADE, BRiaHTON,

AND MILLS 7i' QTJADRANQLES.

Baenunento northeast to San Joan school, tbenoe to Fairoaks, south to Soudan, southwest alone Southern Padflc Railroad to Routler, south to Walsh station, and northwest alone Southern Padflo Railroad to Brlchton.

Sacramento, 3 milo northeast of State Capitol, at intersection of roads; Feet,

iron post stamped *'39 B" 39.320

Ben Ali, 2.5 miles east of, 150 feet west of windmill, at intersection of roads; iron poet stamped "69 B'* 68.576

San Juan schoolhouse, 1 mile east of, southeast comer of field, at intersection of roads; iron post stamped B " 190. 625

Fairoaks Junction, 300 feet east of switch, at southeast comer of field, north of track; iron post stamped "113 B" 112. 973

J

16 Spirit Levklinu In Caufoknia, Iiwi To I'Jio.

Vat.

Boutier, oppuedtc etatiuo, north of county iTd; iroDpciat HUuDpod"68B'*.. 08.tKIIi Walth, at Buulhwest of fii'ld, opposite eoun; iwn post sUmped

Socnunsnto north tloag XuTtrUlt cud to lulu of road at sortbwsit eoim of

K. 13, T. 10 v.. B, I E.. Uian >ut to qiurtm conac dd iodUi itda or nc. 10, T. 10

n., 8. 0 E., tha&ca HiBth to F&lI04kl.

Sacnimenlo, 5 miles nurlh of capilnl. 250 Cct north of houM, 100 feet west of comer al L of road; iron post atftaiped "28 B" JJ.mt

T. ION., R. 5 E,, mirthweat corntTof sec 19, atintETSectionof rcodrunniiig

east from main road ; imn post stamped "31 B" 30.862

T. 10 N., R. 5 E., southwest comer of aec. 13, 1 mile aoulh of Ccnier liii.iu erhoolhouBe, eusi side of road, at angle U) DCKth; iron post l&mped "89 B" MS.9S1

Antelope, 2 milca Dortheaat of, at edge of Southern Paoilic Railroad righl of way, norlhof road at crossing, weat of ti&ck; iron pat stamped "14G 11" I4ti. 130

T. 10 N.. R, 6 E.. near oenlr of see, 26, Boulhcasl comer of Sylvan school-

hoilSf yard at crosaroada; iron "151 B." 151. :;1J

Voclu ol toad S.i mUcs aail at Elaeo ouUi to csnlai llie of T. 10 H., tliancc aut a.lt mllai to Fotk road aaai Dr; Cnak, Uiatim aanth aod lontbvsit to Bacraasnto.

Roseville. 8.6 miiefl west by 2.8 miles south of, in southwest ariftle n! niasroads, 0.25 mile east of aonthewt corner of w. 16, T. ION., R.6 E., 1,000 feet Boutb of whit house, in fence comer; iron post stamped "81-R"..

DryCreek, 0.4 mile weel of, west of road, tietween sees. 14 and 23, T. tON., R. F... at srovp of oaks, in lia-xp 'if IW-inch iwk Iree, 60 feel we.st of wiond-claaa road; spike; wilh aluminum (ag stamped "74-84" 74.91

Sacramento, 9 miles northeast of, east of road through Haggan grant; iron

post slam|>c<) -(Hi B 190S, II ' 67.007

Sacramento, 8.2 milea norihca-t of, mih iMink of small creek, east of road through grant, in liasc of 10-inch coKonwood tree; spike; aluminum tag Btampcd "'53 S7'' 53.38

SacramcDio, 5.G miles northeast of, east of road, at road junction, 50 feet eaet of gate lo ranch house, at fence corner; iron post stamped "50, B. T., 1908, l{" 50.673

Sacramento, 3.2 miles norrh of, east of mad, at road junction, 20 feet iouth of fence corner; iron post stamped "39 B" 39.240

Sacramento, 2.4 miles norlli of, eal of niatl, at fen<-c line, 0.25 mile north of bridge; iron "C. S. E. IV B. M. 10 33.5" 29.925

Sacramento, 1.6 miles north of, north of road, 400 feet oorthotN. E. R. R. crossing; iron (I'liitcd StalcH Corps of Army Eiigincerji,' B. M. 8, elev, 28,5) 24. 991

Pout Dou Sytran ictaool gouttiwait 3.9 mllti, tance nortbwatt 1 mllai to fork l.t tnllai nartliweat of WaneE*- itaUon.

Sylvan school, sec. 20, T, 10 N., R. 6 E., 2.4 mile,' poulhwcsl of, south of road, opposite Twelvemile House, 25 feet south of southeast comer of IHinh of h.Hel; irm |kw( "108 I! 1908 H. V." 108.900

Warici.'!!, 700 feet east of slaliou, west of riylil of tta>-, 35 feet west of mile-

101. at fence line; ir..n piwl sianiiHul "107 B IHOS U. li." 1U7. 106

Looilty JLUuwu aa V. S. Eogiueer

Psimaby Leveling. 17

RoseiUle lontb and eait 8 mltoi (part of line to Oranferale).

Roeeville, 0.4 mile south of, bridge over creek, in top of floor; spike painted Feet. "150 98" 150.08

Rleco loatb 8.7 mllei to Fork road, thenoe east 8 miles.

Riego, 1.3 miles south of, north of road, in top of granite post on county

line; aluminum tablet stamped "37 B 1908 B. D. 1" 37.551

Sixmile House, 3.5 miles north of, at intersection of road running east from

main road ; iron post stamped " 31 B " 30. 862

Point 6.6 miles northeast of Sacramento east via Arcade to point 8.6 miles east of Ben AU, thence south to vicinity of Del Paso and west to forks of road 8.4 miles northeast of Sacramento and 0.86 mile northeast of brldfe over American Blver.

Sacramento, 5.6 miles northeast of, east of road, at road junction, 50 feet east of gate to ranch house at fence comer; iron post stamped "50 B 1908 B.T." 50.673

Ben Ali, 2.5 miles east of, 150 feet west of windmill at intersection of roads; iron post stamped "69 B" 68.576

Del Paso, 2.4 miles north of, at road crossing, 60 feet northwest of oak tree, 20 feet south of road; iron post stamped "94 B 1908 B. T. 1" 93.865

Del Paso, 0.25 mile west of, at junction of roads, 25 feet west of gate to headquarters of ranch, at telephone pole; iron post stamped "90 B 1908 U. 1 " . 91. 030

Del Paso, 2.2 miles west of, west of road, at gate and junction of road; iron po8t8tamped"44B1908B. V. 1" 43.950

Del Paso, 5.7 miles west of, west of Southern Pacific Railroad, 40 feet east of gate, near telephone pole at fence line; iron poet stamped "30 B 1908 B.W.I" 30.405

Twelvemile House east 1 mile, thenoe north 8.6 miles and west and south to Walsh.

Twelvemile House, 1 mile east by 3.5 miles north of, at southwest angle

of fork of roads; iron post stamped "B 1908 133 1 " 133. 105

Brighton school, 0.5 mile south of, west of road, north of fork road to west; iron post stamped " 68 B 1908 2 " 67. 832

Sacramento south 4.3 miles, thence east to Walsh.

T. 8 N., R. 5 E., southwest comer of sec. 19, southwest angle of crossroads;

iron post stamped B 1908 3 " 23. 936

T. 8 N., R. 5 E., south side of sec. 21, southeast angle of intersection with

upper Stockton road, opposite road house; iron post stamped "30 B

1908 4" 29.820

T. 8 N., R. 5 E., southeast corner of sec. 23, at northwest angle of crossroads;

iron post stamped "42 B 1908 5" 42. 409

Bench marks In vicinity of Falroaks.

Fairoaks, 0.7 mile east of, southwest comer of bridge, on concrete; chiseled circle painted "U. S. B. M." 151.17

Fairoaks, 400 feet north of store, in center of road comer, in notch in base of 50-inch oak tree; nail with aluminum tag stamped " 181 35 " 180. 78

Fairoaks, bridge over American River, in west face of south concrete pier; aluminum tablet stamped "89 B 1908 16" 88.603

Fairoaks, in front of railroad station; top of rail 104.81

95094**— Bull. 481—11 2

Is Rpiiitt I,F.Vei,Isg In California, Iiw" To 1910.

AMERICAII. CLASKSVIIXE. FOLSOH, ADS SCOTT SAXCH ty QTIAS-

PolBt IJ BiUai DOttbvait of Sloofb Hook.

Slough Doutie, 1.8 milLiB nonhwetil of, where Grant Liue iuterei-l. poit

Sacrttmento-Jackson road; iron poet slapped "ISO B 31)" 150.652

ysriu at roKd 1 mUa oaat bj 1J> Bllsi BOrth of TmtTsBilla Hodh aut to Bride* BoBw. OB FolMnn road.

.Twelvemile llmiae, milet* oast by 3 miles north of, oast of imhiI. al

angle; iron post "aoi IJ 1908 U" 20(). G25

Twolvemile Houne, eaL by 3 miles north o[, on Btimmil, O.o niilo

estofr&nchhouRO; iron p.iwt tam|)ed 'I'M U IWIHT" 250. 12

Bridca HevM Dortb to roltoo.

ficott ranch, 2.2 miles south of, 'in tnad, at gate to

private road from south; mtii etAmped '184 B 1908 9'' 1H4. -WKl

Bcott ranch, l.Ci miles south of, 20 feet weal. o( road, 0,4 mile mirth of angle

in road, in nolrh iit baae of oak tree; nail with aluminum tag

'Htamped "206 22" - aiil.02

Bcott ranch, 1 mile north of, 60 feet west of road, in large bowlder; tablet

ttlamped " IBS B 1B08 8 " 197, 993

Bcott ranch, t.7 miles north of, 200 feet aorlh of private ruad from wti,

east of road, in not(?h in root of 48')nrhoak tree; nail scribed and paint

'U.S. B.M. 21120" :;10.96

'Bcott , 3.6 miles north of, 100 feet south of big brid, at eat edge of

mad, in lodge: ahiminum tablet fitampeil "225 liMlS H 11" 225.423

FolMoni, 5 miles south of, 100 (eet east of interaeetion of roads, in center of

road; point on large bowlder painted "U. S. (i. S, I!, M. 341 25" 341.57

FolRom, 3 miles south of, GO feet south of Alder Creek bridge, at east edge

of road; inm post stamjK'd "237 B 1908 12" 237.467

Folsom, northeast I'orner of Calholli' Church lot; iron pout slapped "224 B

FnUim, infnmt of-<laliim; of mil 193.5

Folgom wait to Falioita.

Orangevale, 0.5 mile west by 2 miles south of. at inlerspotion nf road.s;

iwn post stamped "24B B ['908 15" 246. (M3

Fairoaks, 2.9 miles nordieasi of, norlliwcst angle o( croasroacis, in notch iu

ba.'K'of 15-inch oak tree; nail with aluminum laj; stamped :!2" 248.81

FoItoBi lontlnroit aloud rail via ITatooia to SaUibnrr.

Folaom, 100 feet east of bridge over American River, in top of large flat bowlder; aluminum ubiet stamyied "162 B 1908 14" 162, 109

Folsom, 0.7 mile west of, north of road, at fence line {U. S. Corps of Engineers' bench mark "58 188-5 ") 185.01

Folsom, U. S. Corps of Engineers bench mark Xo. 57 180. 804

Polsom, 3.3 miles west of, north of road, at fence line; iron post stamjied

"167 7 B. M. 51" (U. S. Corps of Engineers bench mark Xo, 51) 164, 182

P'olaom, 3.5 miles west of, stone briilge over Alilcr I'reek, southeast corner of granite guard: aluminum (able slainpeii "lo.j B 1908 B. A. 1" 165.374

I Looally known aa U. S. Engtnaet DrpBrtment,

Primary Leveling. 19

Natoma, 0.7 mile west of, south of road, at ience line; iron post stamped Feet.

7 B. M. 43" (U. S. Corps of Engineers bench mark No. 43) 136. 179

Natoma, 1.7 miles west of, south of road, at fence line; iron post stamped

"127 3 B. M. 41 " (U. S. of Engineers bench mark No. 41) 123. 787

Natoma, 2 miles west of, southeast comer of bridge over Buffalo Creek,

top of granite guard; aluminum tablet stamped "129 B 1908 B. B. 1 " . . 129. 162

Point neac Roferille east and loutb to Ofngwrnlt,

Roseville, 0.4 mile south by 1.9 miles cast of, south of road, at fence line, on bowlder; chisel point painted "237 B. M. 100" 237. 11

Orangevale, 5.5 miles north of, south of road junction, in fence comer;

iron post stamped "236 B 1908 B. Y." ." 235. 708

Orangevale, 4 miles north of, at junction of road, 50 feet south of bridge at fence comer, in base of 24-inch oak tree; spike with aluminum tag stamped " 195 B. M. 102" 195. 32

Orangevale, 2.5 miles north of, east of road, at junction, in fence comer, 500 feet south of white house; iron post stamped "203 B 1908 B. Z." 203. 293

Conrtland 16 quadrangle; BotUdin, Isleton, Jersey, and Bio Vista quadrangles.

Contra Costa, Sacramento, San Joaquin, Solano, And Yolo Counties.

The elevations in the following list are based on the results of precise leveling along the Southern Pacific Railroad and along the Sacramento River, and accord with the results pubUshed in Bulletin

The leveling was done in 1905 by R. A. Farmer, in 1906 by C. L. Nelson, and in 1908 by B. A. Jenkins in cooperation with the State.

COTTBTLAin) 16' QTJADBAITOLE.

Tnmont east 4 xnilet. thence south 6.5 miles, east 2 miles, south 8 miles, and west to

Binchamton.

Bulkey's ranch, southeast comer -of yard, west side of nwid; iron post Feet.

stamped '34 B " 34. 123

Hance Timm's house, 400 feet smtheast of, west side of road; iron post

stamped "31 B" 31.334

Jud Kinj's ranch house, 0.5 mile west of, southeast corner of stc. 36, T. 7 N.,

R. 2 E., southeast comer of field; iron stamped *'21 B " 20. 708

T. 6 N., R. 2 E., near northeast comer of sec. 24, southeast comer of pasture

fence; iron post stamped "8 B " 7. 409

T. 6 X., R. 2 E., 1 mile east by 0.25 mile north of Peter's house, southeast

comer of field; iron post stamped " 17 B " 17. 121

Jnd Kind's ranch house east 2 miles (double spur line).

Jud King's house, 2 miles east of, on north and south fence line, 50 feet east of levee, 150 feet southeast of dead tree on levee; iron post stamped ' 9 B " 8. 777

Bench mark at forks of Bntter and Steamboat slonchs.

Forks of Sutter and Steamboat sloughs, 0.7 mile north of, 0.25 mile northwest, of H. M. Donaldson's ranch house, 300 feet west of Sutter Slough, in northwest comer of Orchard lot; iron post stamped ''6 1906 B. N.'*. . 5. 916

i:

Pirit Levelisg In Cauforsu, 1907 To 1910.

OoaftUad MBtbuM to Walaat Osn.

Ishtiid. kt htuul ui Sloamhoai O.o iiiil north tiring, nl Een- Ilumw; Jiero oi pigt (Iwlow le<*el)

Giaod Island Ilridge, 3 miles tittst uf, 100 feet eonttaeaet <if 0.25 mile northwest nt pump house, at southeast comet of yard, won of rofui: iron pnai eUimpei) '--2 B. N. 1906" (betoveea level)

FtaakliB Kwd.

('ourtland. 1.2 miles north of, at eaat edgo of lovtw, 15 feet iouth of school, in 'inch oak tree; mitl wilh aluminum tag etmped "17 41" ]

Fikliu. 4.3 miles aoulhweAt by 5 miles WBOt of, im eciulb edge of se<-ond' rlaaa road, WU foet aoutheaat of creamery, in pyramiil on of 30-inrh oak IrvMi; nail wiih aluminum tag lilamped "6 39"

BOnjlin. IBLSTOV. JZBSET, AXO RIO TISTA 7}' OTJADRADOLES.

Tolandi '—'-f month aero Sbermaii Iiland to naitk bank or Saa JoaqiUn Ktni. tbaoc* wait to Aatlocli.

Tnlande Imdln. 3.0 milt-e ajulh vi, al south end of road cniiwing ?hemian Island Houlhward froai Tolands Landioc:. at turn 0.5 mile south n( pump bouse, 100 feet north of San Joaquin River, south of nd. 0,25 milo mmI of house; iron post stamped " — 1 1906 B. N." (below level) —

Bneb BaA at aorthMM eormu of MO. I, T. t X. I.

T, 4N,.R.2E .rom.Tofppcs. II, \2. 13. an,l 14, sidonf road; iron p-wl stamped "19 R" lg.900

lo fork of and Staua-

Rio Vista, 3.7 miles of, O.fi mile south of Westgate's place, 250 feet west of river, 200 feet west of houw> on north side of road; iron post stamped "—1 B. N'. I90G" (below sea level) —1.130

Walkere landing. 0.7 mile north of, we.'rt.eideuf rood, 150fcet west of Steamboat SlouRh. 2.J0 feet northwest of J. Tlollenbeck's house; iron post etampeil "4 ISOG H. N." 3.600

Walnut Qton soak aloiv ut ildt ol Trier Iitaad and wett to Rio Vlcta.

Tyler Island, east side of road across island, 200 feet west of Mokelunmo

River, on ranch '"J " of Bauman properly. 0,25 mile south of pump house;

iron post stamped "'-l X 190li" (below eca level) -1.088

Camp C, 140 foet east of house, 100 feet north of Mokelumno Kiver, 100 feet

northwest of barn ; iron post stamped "01906 B. N." (below sea level).. —0,282 Tyler Island ferry landing, l.)0 feet west of, north side of rond, 50 feet west

of saloon; iron post slampcl -'3 1906 R. N." '.. 3.040

Point 1.1 mll (ODthwait of Bncki Luidlnc Tla Bruk't pump taonn and Staton Iiland to Brannan'i ranch "J,"

Tyler Island, east of road, 200 feel west of Mokelumno River, on ranch "J" of Itrannan's property, 0.25 mile south of pump house; iron post stamped "-1 1906" (below sea level) — 1.08S

IfilMAET LEVELIKG. 21

ttaganivllto lonthweit dong Vortb Fork of Mokeluniiie Biwt to Ooldm State oa&- nery, thenoe month and wMt to Andma Idaad pump home, thenoe nortli to Idatoa.

Hagansville, 250 feet east of Staten Island pump house, on bridge across Feet canal; bolt head painted "U.S. -4 B. M. 36 " (below sea level) —3. 70

Staten Island pump house, 1 .8 miles south of, 20 feet south of house, camp 8, at comer of garden ; iron post stamped "—IB 1908 20 " (below sea level) . — 1. 274

Golden State cannery, 100 feet south of, in cottonwood tree; aluminum tag

stamped "4-47" (U. S. Corps of Engineers bench mark 26) 3.91

Golden State cannery, 1 mile south of, at comer of China House 100 feet west of Mokelumne River; iron post stamped "-2 B 1908 21" (below sea level) — 1. 840

Golden State cannery, 1.7 miles southwest of, at angle in canal, 1 mile west of pumping plant; aluminum tag stamped "—8 48" in post painted "U. S. -8 B. M." (below sea level) -8. 58

Andrus Island, at Jackson Dam, where Isleton road leaves levee and where Jackson Slough joined main slough before it was drained o£f, 50 feet west of house, 10 feet west of road; iron post stamped "—IB 1908 22 " (below sea level) —1. 229

Isleton, 1.8 miles south of, where road to Golden State cannery leaves Jackson Slough, 50 feet north of bam, at road angle; iron post stamped "B- 1908 -1 23" (below sea level) -0. 962

Jackson and Lodi 80 quadrangleB.

AMADOB, SACRAMENTO, AND SAN iOAQUIN COUNTIES.

The elevations in tlie following list are based on the results of precise leveling along the Southern Pacific Railroad from Benicia across the Gait and Woodbridge quadrangles.

The leveling was done in 1907 by B.A.Jenkins, except for a portion of that in the Jackson and Lodi quadrangles done by L. F. Biggs, the latter employing yard rod and prism level, and the former the ordinary Y level.

The work was done in cooperation with the State.

JACKSoir sty qtjadranqle.

Carbondale northeast 4 xnilet. thenoe northwest to point 2 milet east of an

Michigan Bar, 3.6 miles east of, north side of road, 15 feet south of fence; Feet, irtm post stamped '*BB 1907 5 255 " 254. 849

LODI 80" QUADBAHQLE. Florin east 8.6 milet.

Florin, 3.5 miles east of, at intersection of roads; iron post stamped "B 32

1907 63" 63.477

Elk Qroire east and northeast alone Orant Line road.

Elk Grove, 50 feet west of station ; iron post stamped " B 49 1907 " 49. 289

Sheldon, at road comer, 50 feet south of Sheldon saloon; iron post stamped

1907 73 31" 73. 523

Oalt northeast alone road 6.4 milet to point 1.7 milet wett of Oonley.

Gonley, 1.7 miles west of, at intersection of roads; iron post stamped "B

1907 62 22" 61.881

Looally known at U. 8. Engineer Departmeot.

fte SPIRIT LEVEILING IN' CALIFORXIA, 1907 TO 1610.

PoUit (Hath of Aistt nit its Bracarlllc BboollitiaH to erontnc ot SlocktoB road nd WfiUn Faoflc Rallvay, Umsca north lU FTuikUa lo point 1 bUu north ol

Brutevillf, JO iLfl WL-sl oi Btlioulliouse, At edge nI steps over ieaee; iron

pwnmamiwrl "B 21 No. 34" 21. Iff'

l-'raiikliii.coruiTof Musuuic Hall; BlumiDum Wblel sUmped "B 1907 1835" I8.fl<' fnuikliu. fi.7iuili mirth nf. 20 feet nonhiifarhoolhoUBo, in angle of fpnro;

iron "H rwl7 l.'.HIi" 15.34P

MacktOB romd booIbi on Wattern Pulflc Bulwa; mR t milei to pout U mile* ontb \iy i ullti wait of TTuikUn.

Franklin, *4, 3 milM enutli by 3 iiiileei west of, a) KOUlheast (.'nmer of bridge! across slough; iron post slampod "B 1907 5 37" 4 9H

Polat I allt dut of XtcblCKS Bi mit aioag read tIs linonk msd Slooih aonn to OiBBt lino. Uw&na kIdbc OnAt Ubb touI to point i nilu DortliHM of Bboldon.

Michiean Bur, northwest earner of achoolhuiise; iron jMWt stamped "BB

1907 () 333 333. .W

Bridge Unuije, 1 A miles north of, weal side of road, 75 feet east of house on

Buinmitof rise, atffnreforner; etampwi '"BB 1007 7 154" 15J,3

Road intanMtlon 1.7 rallai mit ol Conler north to Slonfh KooM.

Blough House, 13.2 mi lea southwest of, where tirst road from W, & R. 'a colony iuteraecterofld; iron pwt slapped "B 1007 73 27" 73.181

Slough House, (1.1 miles aoulhweel uf, in front of ranch house, west aide of

road; iron post sl4upped "B 1907 123 28" 123. 47L

6iuu Houae, 0.6 mite southeast of, iu top of south piei of UcCntcken's

timlsi'i bronze label r'lumiXHl "H WdT ll;J39" 113.47;

Point nau Conlar nortbengt nloDC road to CarbenOal*.

Couley, 200 feet miriheast of station, railroad croasiufr; top of rail 74.8

Clay, northweMt corner of aohoolhouBc; iron po8( stamped "BB 1907 10523". 105.291

Clay, 11 miles northeast of, 200 feet south of Alabama House, at junction of road loClay, at feiiei' cursor- inm post sUmpcU "BB 1907 237" 336.695

Carbondale, iu frout of nation; top of mil 214.0

Ureonk lontb Tl> WUbnr to Alabamn Hook.

Alabama House, 3.5 miles northwest of, 250 feet west of junetion of road, 2

feet west of gatepost; iron post stamped "BB 1907 2 ISO ' ISO. 109

Point naar WUbor wait alone road to point 2.t mllai north of Clay.

Alabama Houpp, fi.O miles wesl of, I A miles west of Weiss ranch house, junction of rnad, south side uf road, at fence line; iron jxisl stamped "BB 3 1907 lU' 140.826

Clay, 3,8 miles nurlheajituf, west side of road, 10 fwl south of gate to ranch house, 25 feet west of gale lo tloiind ranch, at junction of road from Slough House to Clay; iron post stamped "BB 1907 4 113" 112,150

Clay, 2,0 miles north of, where lane from house intersecla road; iron poat

stamped " B 1907 33 103 " 103. 260

Maw Oranl (ata lontb to point 1.7 mllai lontb of Dry Creek icboolhooM.

Swifts much, 400 feet west of ranch house, 10 feet north of road; Iron post Btamped"B1907 153 25" 153.218

leveling. 2d

Banoli mark at Tree East triangnlatlon itation (by double tpux Use in 1908).

Slough House, 1 mile southwest of Tree East triangulation station, on land owned by Archie Mull, on Jackson road from Sacramento, near Cosumnee poet office, at foot of tree, on west side of road, about 16 inches above Feet, ground; iron post 189. 819

Lodl eait alone wagon road to Lookeford, thenoe north to Dry Creek.

1.2 miles south of, east of railroad at crossing, north of road, at angle of fence; iron post stamped "45 " 45. 286

3.6 miles east of, where road from south joins road, angle of fence; iron post stamped 1907 72" 71.523

Lockeford, 5.8 miles north of, southwest comer of Elliott - schoolhouse grounds; iron poet stamped "B 1907 105 15" 105.089

Elliott weit alone road to cemetery entrance.

Gait, 4.6 miles east of, at intersection of roads; iron post stamped ''B 1907 64 16" 63.619

Zockeford eaet alone wagon road to Clements, thence north to point 1.7 milei month

of Dry Creek echoolhoase.

Clements, 4.4 miles north of, 20 feet west of road in front of deserted house; iron post8tamped**B 1907 214 26" 21762

lACkeford south alone wagon road to Farmlngton road.

Lockeford, 4 miles south of, where Lodi-San Andreas road crosses Lockeford- Stockton road, 40 feet southeast of, at fence comer; iron poet stamped "B 1907 80 9" 79. 459

Lockeford, 8 miles south of, angle of fence at intersection of roads; iron poet stamped *'B 1907 72 10" 7L 583

Farmington, near junction with Farmington road ; iron poet stamped " . 66. 551

Clements south along wagon road to point near Peters.

Clements, 8 miles southeast of, at section comer on north side of road; iron

poststamped *'B 1907 194 13" ' 193.802

Bellota, northeast (!oraer of post office; iron post stamped B 1907 130 14 " . . 130. 232 Peters, near southeast comer of junction of Peters-Linden road; iron post stamped " 102 " 101. 826

Oalt west along road via New Hope to Walnut Ghrofe.

Gait, 3.5 miles west of, north side of road, 200 feet east of intersection of fence from north; iron post stamped "B 1907 29 17 " 28. 467

New Hope, Don Ray & Co. store, southwest comer of cement porch; aluminum tablet "B 1907 13 18" 12.954

New Hope, Don Ray & Co. store, south door of; center of metal doorsill (county bench mark 13. 36

Lodi west along road via Woodbrldge to Brack's Landing.

Lodi, northwest comer of opera house; aluminum tablet stamped 1907 50.21" 50.604

Woodbridge, northwest corner of Masonic Hall; aluminum tablet stamped

1907 45 19 " 45. 805

Woodbridge, 3 miles west of, intersection of roads; iron post stamped *'B 1907 29 20" 29.049

SPIRIT IXVEUNG lil C&UFOUSU. 1807 TO 1910.

Spar from BneVi Xtatnt to potato bmi pwipbc puat hgr

Brack's Loudiii. amtheut rontcror varvhouxe; inin posi stAmpoJ "It liMIT

'i IailUi MaUut to Kaltlnua'i nuuk. UniM to Soatharn Puuai XAlItDftd mlkapon M.

Br<:k'B Ijuidini;. ,7 miles mulh of, un TiminuB tnad, north ido rJ rnod. 400 fet WMt of le%-'; inm ikkiC slampfl "B 1007 3$" tamptrd 4)

BrsrkVLiulini>. 9.limilf?)uUicjuit of. 500fe<-( suuth of Eettleman'e ranch

Fivemilp House, 1,000 feet north ol, west edge of Lower Sacramento road

? lane from wml interaocta; iron poet Hlamped "B 13 10"

Lodi, 7.2 miles south of, 15 feet riorth of milepost 97; iron pest stamped

" B I&07 2S '" 2S- m

Okll (OBlliiiBst ud aaat to nwd latanaiitloB 1 sHo Mat of SBtTwiM to maMnr.

Gall, 30 feet west of track, on line with north ond of Blallon; iron post stamped "11 1901 4i;" 45.576

BjFTon Bud Ttacf IS' qtudrancIeB ; Holt, Lathiop, BiMktoa, Utd ITalon Igland T}' AL.tHEDl, rOSTK* COSTA, KAS ANft KTA.MNI,Atl COVNTIES.

The elevations in the following list are based on the precise line from Benicia by (", H. Semper,

Most of the leveling was done by L. F. Biggs in 1910, although a part of that in the Byron quadrangle was done in 1907 by B. A. Jenkins, The State cooperated in the work.

HOX.T, LATHSOP, ETOCETOIT. AKD TTNIOir ISI-AHD TS' QUASHAKaiBS. Buta weit ud north 10 Grant LUi *, Uiancs lonthwsit to point 0.8 Bkla unth

Bania, 1 miii- wwt of, ni.rth sicl! oi mad, in lm- nt Ick-phone pole 42/9; Feei.

S))ikewilh aluminum tai; "SI" 31.33

Danla, 1 .5 tnilfs wx-st of, at T mad Boulh, in basi- of Iplephone pole 41/29;

spike with aluminum tag stamped "33 " 33. 04

Banta, 3 milea west of, at T nmd south to Tracy, in base iif telephone polo

40/12; spike with ahiniiniim tai? stamped "27" 27.32

Bantft, 3.!) miles west of, at T road north; in base of telephone pole 391;

spike with aluminum tag stamped "27" 26.91

Trary, 2 miles north of, 600 feet north of ltoj;l<'y's rancli house, eaat of rood

at fence corner; iron post almpcd "9, 1910, 1" 9. 471

T. 1 S., R. 5 E., comer of sees. 5, 9, 4, and 8, in base of ; spike with

aluminum tap stamped "5" 5.11

Tracy, 3.5 miles north of, 1 mile south of Naylee school houev, where road

turns north, in root of poplar tree; copper nail with aluminum tag

stamped "7 " 6. 89

Pbimaby Leveling. 26

Tracy, 4.5 miles north of, 50 feet north of Naylee schoolhoiue, 200 feet south of Old River steel bridge, west side of road; iron post stamped 1910, Feet.

Grant Line steel bridge, on southeast comer of abutment; chisel point

painted '*18" 18. 03

Grant Line steel bridge; 22.5 foot mark on gage 14. 41

Grant Line steel bridge, 2.5 miles west of, 175 feet south of levee, 150 feet south of pump house, on fence line; iron post stamped "2, 1910, 3" 1. 724

Grant Line north and eait to Stockton.

Grant Line bridge, 2.5 miles north of, south side of road, where road crosses levee; iron post stamped "2, 1910, 10" 1.489

Grant Line bridge, 2 miles north by 1 mile east of, north side of road; spike in base of comer fence poet; aluminum tag stamped " 2. 92

Bridge over Middle River, 200 feet east of, at T road north; iron post stamped *'6, 1910, 11" 5.603

Middle River, surface of water under bridge November 2, 1910 0. 14

Middle River bridge, 2.3 miles east of, 0.6 mile south of Fairchild schoolhouse, at T road south; spike in base of telephone pole, marked "6 " . . . 5. 78

Fairchild schoolhouse, 1.2 miles north of, 2.5 miles southwest of San Joaquin bridge, opposite road house ; iron poet stamped 2, 1910 " 1. 460

San Joaquin River, surface of water under bridge November 2, 1910 0. 1

San Joaquin Bridge, 60 feet east of, north side of road, at fence line; iron post stamped "7, 1910" 7.156

Stockton, 2 miles south of, at jimction of French Camp and Roberts Island roads, west levee of canal; spike in base of telephone pole; aluminum tag stamped 15.37

Stockton, south edge of town, junction of South Center and East Jackson streets; spike in base of telephone pole; aluminum tag stamped '13". 12.46

Stockton, west door of north entrance of San Joaquin County courthouse, in angle of wall; bronze tablet stamped 18 B " 17. 953

Holt Blong road north to Black Slough (unchecked ffyiir line).

Holt, 300 feet weat of station, south edge of right of way, east edge of road leading south; iron poet stamped "10, 1910, 15 " 9. 935

Black Slough Landing, south of, southwest comer of bridge over canal; top of bolt iminted -3 " (below sea level) —1. 40

Black Slough Landing, 90 feet northeast of Gorden's house, on edge of levee, San Joaquin River; brass-capped pipe marked "U. S. E. D. No. 206".. 11. 327

Middle RlTer weit and north along road to Holt.

Kingston schoolhouse, 300 feet northeast of, at angle of road to north, west side of road at fence line ; iron post stamped 7, 1910, 14 " 6. 422

Stockton, 5.8 miles west of, 200 feet east of milepoet 1127, on levee at fence comer; iron post stamped "9 " 8. 805

Point 1.6 miles north of Stockton weit to TT. S. Corps of Engineers ' bench mark 0 J

miles east of Shipyard Island (checked spur line).

Stockton, 1.5 miles north of, 8 feet north of milepost 94, east side of track, near fence line; iron post stamped "20 B " (United States Corps of Engineers value 23.388) 20. 075

Locally known as U. S. Engineer Department.

26 gPIRIT LEVELING IX C.iLrFOKNIA, IBOT TO IftlO.

Siorklnn, 2 tnilw norUi o(, ooutbwfvl Abutment of bridge over CWIftVtoaa RivM: lupofltulibiMd ttukrktd "'27 " 88.41

Weetm Padfir cnmitig; top of iit aH

Sluckldu. 2 mllM n< ut, uu lower SocwnenUi mad. B feet wpulit of multi- Must nbutmi-nt of bridge over CaUvens Rivir; poppy boll in vBp w4il ttluiuiDUD) tHK jumped "IS" I

IjOwct SwnuniMiIo mad bridKe, 1,2 milea reet nf, north love tuiul, '200 toot niiitiiwct of iimeT, in stump; cupper nail wiih Kluminum Us "Umpt-il "20" L'0.2

Lowrr SarrsniMilo nd bridge, 2.5 milcia west ril, nurl.h €e of Itvee, nl imrthtMial of huiiiH< at lmilii'E place; Irou jiuet <tlAmpd "'3" 3. JTj'

Smilli's hm;w>, 1 mile wot nf, spike iu base of power pole 5/10; aluminum tag Kiamptl " — 1 " (below wa level) t4(

Klrow<>d Karni Nu, 2, SOOftvt eiwt of bani; spiknitibMeot powpcilifl/7; aluminum Wgwlsimpmi "i"

Shipyard Imlaud.D.S mile iNui of, eiui bulk of San Joaquin at pump-

ingslation, inlnpofapilfi; cflpperbollwilh aluminum tagelamped "K". K30I

Shipyard Island, 0.2 milv eust vt, right bank of San Joaquin River, 40 ftwi. backof It'VPG midway bi!twc<!n hoiufl and bam; iron poet marked "U. 8. E. D.No- aK>"(Unlld Statw, forn ol Enginecn. value 4.770) 1

Pout tA mllM awth of Scant Una bride* to CaMp So. 1 LaadlBc.

Victoria Iclaud. 0,6 mile i-ael of. -40 feet Buuth of Middle River levpc, 5 feet

wiulh of red tank Iioubp; iron poat stamped "4, IfllO. 17''

Camp No. 1 Landing, uit liip of levee. 50 feet iiurlli u( baru in top of auub-

biiig ciippiT iioil, Willi aluminum ijig lli" 18.40

Poui K.S BUMi awt of Middle BHar lontliBaii lo fitatb Canp. Itrjiit Bridge, wiutli imuI ;iljuiiueiii r.f; aluminum laiilel stamped "21,

111 10. 30 " 20. 639

Ilrjut l.L' miles ea.-t i.f. !it T roiid aoulb, in telephone pole; spike

with iilumiiiiim lyg stamped 1 1" 10, 92

i-reiL< h Canip. I,:! uiilcs souili of, eai side of rnul at T road went, in baae of

lii.usi lro,>; Hpiiie w itli iilinniiumi ui' camped "IK"" 17,27

l-'ri'iiili (Hnip. -M mill's .-'iiiiih of. on east oiile of milroad at road cro!<pinB,

TRACT IS QUADSAKOLE. Paint 1 mile wait at EiUi louth and west to San JaaijulD , tbeuct nortliwtit

Ellis, 2 mili-c Noudi of, ill Wi'sieni Pacilir Railway croHsitin; spike iu baac of li'li'ptioiK- pole; aluminum lag " lUK'' 168.22

T. :t S.. H. eoni.Tof [<e.T. 4, 5. S. and 2.5 miles south by 1 mile wisii of 'I'r.ii y, ai Weaieni I'a'itie Railway iroasing; iron piwt camped IIS, lillll,,*' 148.371

Tun y, :l,:. loiles wiiilli l.y I mile we,-l of. 2 miles soutli of Jefferson wlioolliiiuse. at railrimd crosMiii]:: [)ike iti liaae of telephone pole: aluminum lag sliimpi'il 11l!f 198. 99

'I'nii y, 1.,'> inili'.s .smitli by 1 mile enHl of. at croKKniads: iron poal stamped

Sim llriilp', 4 miles west of, at Soulliem Parilic iTossing; spike in

basil nf leleplioiiepiile; aluminum tajisiumped "S:!" 83. H

Siiii Jiiiiipjiii Uricigi', 0,.') mile we.nl of. at T road; iron clamped "45.

Itmi, 7 ' 47.156

Peimaby Leveling. 2Y

San Joaquin Bridge, 1 mile northwest of, east side of road, at second-class Feet.

road to east ; spike in base of telephone pole ; aluminum tag stamped 'Ml " . 43. 1 9 San Joaquin Bridge, 2 miles northwest of, opposite T road west, in base of

telephone pole, scribed and painted 33 ; " spike 35. 32

San Joaquin Bridge, 4 miles northwest of, 5 miles southeast of Banta, east

side of road, opposite power pole 19/2; iron post stamped " 37, 1910, 8 ". . 39. 227 Banta, 3.7 miles southeast of, at crossroads ; spike in base of telephone pole;

aluminum tag stamped 31 " 33. 14

Banta, 2.5 miles southeast of, opposite second-class road west; spike in base

of telephone pole ; aluminum tag stamped " 23 " 24. 48

Banta, 1.9 miles southeast of, at Western Pacific Railway crossing; spike in

base of telephone pole; marked " 19" 20. 75

Banta, 1 mile southeast of, at T road to east ; spike in base of telephone pole ;

aluminum tag stamped "18" 20. 11

Banta, 10 feet north of milepost 75, south side of track; iron post stamped

*'22.181" 22.119

Point 1 mile west of Elllt eait to Tracy.

Ellis, 1 mile west of, 4 feet north of milepost 69; iron post stamped

102.656 B " 102. 594

Tracy, 2 miles west of, at road crossing; spike in base of telephone pole;

aluminum tag stamped "67" 66. 93

Tracy, 1 mile west of, spike in base of milepost 71 ; aluminum tag stamped

"65" 64.72

Tracy, 0.4 mile north of station, 4 feet north of milepost 72, on fence line

north side of track; iron post stamped "54, 1910, 8" 53. 875

Point 8 miles weit of Banta touth to Tracy.

m

Banta, 3 miles west of, at T road south to Tracy; spike in base of telephone pole 40/12; aluminum tag stamped "27" 27.26

Tracy. 0.4 mile north of station, 4 feet north of milepost 72, at fence line;

iron post stamped "54, 1910,8" 53.875

BYKON 16' QTTADBAKOLE. Bethany Ferry to Bethany.

Bethany, 100 feet east of station, on edge of right of way; iron post stamped

"36, 1910, 4" 36. 145

Point 1 mile west of Camp No. 1 Landing to Blzler.

Camp No. 1 landing, 1 mile west of, south bank of canal, 10 feet south of

pumping plant, in top of pile ; copper nail with aluminum tag stamped "2" . 2. 42

Old River Farms Co. Landing No. 5, 800 feet east of, south edge of levee at road leading south, 40 feet east of canal, 50 feet south of pump house; iron stamped "2, 1910, 18" L 727

Old River Farms Co. Landing No. 3, 50 feet north of office, in base of telephone pole; spike with aluminum tag stamped "7" 6.77

Coney Island, upper end of, 1,000 feet south of edge of east levee of old river, 150 feet south of warehouse, 5 feet north of old building; iron post stamped "7, 1910, 19" 7.158

Old Ferry, 1 mile north of, west bank of canal, northwest comer of house, in root of willow tree; copper nail with 0 aluminum tag stamped '' 1 " 0. 65

Mouth of Italian Slough, north levee, at landing; nail in top of snubbing post; aluminum tag stamped '*11 " 11. 02

Hft fiPIEUT LEVEUXd IK CAUPOBNIA, 190' TO ISlA.

Italian Slough, O.T taiio north of, junction of read west lo &t WMt levee, neu narthwMl cmier of liouee; iroo poet Btomprd Fia

"1, 1910, 24" l.SB

Italian Slough. 2 mile north of, weal levee of Old Eiver, 10 feet PoMih of hoiiBc. in root of willow tree: copper nail with alum inum tag stamped "0" U. 5V '

ManmM llouae, 1.3 miles south of, west leve of Old Rivef, 20 feet north

uldhuuae, in boseof willow tree; spike with aliuntnum ta stamped 'T' 1. -Of

Manmiin Ilouse, 1.000 (eel aortb of, west levee of Old River, oppodte mnal between Victiria atid Woodward Island, al northeast corner of oldhotwe; iron post stamped '3, 1910, 25" 2.958

Mansion House, 1.3 mira of, muth bank of Indian Slough, at pump house, in base of power pole; spike with aluminum tag stamped "2 ". . I, 77

Mansion House, 2.5 miles weet of, 2 miles aoulh and 1 mile fast of Dixler, 200 feet muIIi of while house, 40 feet weal of Indian Slough, al end of lane; iron post stamped "6, 1910. 20" 6. 5S4

Bixler, 2 milos south of, at (Toaeruad. is baaeof gum tree; epiko with aluminum tag stamped "13" - - IL93

Bixler, 1 mile south of, at troaBroads, in base of power pole 0/20; epikv with aluminum lag stamped "9" 9.61

Bttbaay Boitb and wut to OaUar-

Bethany, 1.5 miles northwest of, at T road west, in base of telephone

pole; spike with aluminum tag stamped "43" 42.78

Mountain House school, 0.5 mile north by 1 mile went of, at T road north

to Billy Cunphell's ; inm poet stamped "76, 1910, 20" T&.Tn J

Byron. 5.8 miles south of. at power line croanng. in base of power pole

6S 12: spike wilh alumijuim lac slaralied "?1 " St. 20

KjTon, 3 miles southeast of. at junction of road lo south, in base of power

pole 1 8; spike wilh aluminum lag stamped "14" 13. 72

1.5 miles south of, at junction of road to Byron Hot Springs, east

of railroad right of way; iron post slapped "23, 1010, 21 " 23. 171

Byron, south edg<! of town, 200 feel south of railroad crossing, in base of

power pole 4,12; Rpiko with aluminum lag stamped "25" 2.5.43

Byron, 2 miles west of, at junction of road lo west, on lenco line; iron

post slapped "IliS, 1910. 22" 164.891

Byron, 3 niilcs west by 2 niili's north of, 1,500 foci east of Moih Creek

bridge, 700 fei't cast of junctiiiu of Martiiu-z and Brentwood roads, 150

feet north of at iHiinl of hill, in bowlder outcrop; aluminum tablet

stamped '209, 1910,23" 208.856

Brentwood. 0.5 mite southwest of, SOO foet south of storehouse west of

ruad, in base of GO-inch oak tree; spike with alumiiuim tug stamped "160" 159.98 Stone House, 1 mile north of, west bank of Harsh Croek, 100 feet south of

windmill, in base of sycamore Inn.'; spike wilh aluminum tag stamped

Slono House, 2 miles north of. 60 feet west of Itlarsh Creek, 2 teet west of

house; iron post stamped "27 1910100" 100.723

Brentwood, 1 mi!o west of, west abulmeni of steel bridge over Marsh

Creek; aluminum tablet stamped "81, 1910, 28" 81.119

Brentwood, 1,5 miles northwHst of, in iiaso of milepost 81, Soulhem Pacific

Railroad; spike with aluminum tag stamped "82" 82.60

Brentwood, 2 miles northwest of, at road crossing, east of right of way;

iron post stamped " 95, 1910, 29 " 95. 249

Frimaby Leveling. 29

Ohara, 0.5 mile southeast of, at junction of road to north, in base of tele- Feet.

phone pole; spike with aluminum tag stamped "84 " 84. 22

Oakley, 1 mile west of, at crossroads, in base of power pole 18/14; spike

withduminum tag stamped "28" 29.50

Oakley, west end of station, 30 feet south of track ; iron post stamped " 19 " . 19. 180

Middle Borer northeast to Empire Cut (nncheeked line).

Middle River, 1 mile north of, in base of power pole 1/3; spike with aluminum tag stamped — 2 " (below sea level) —1. 947

Middle River, 1.8 miles northeast of, west side bridge over slough, in floor; copper nail marked " 1 " 0. 868

Middle River, 3 miles northeast of, at Empire Cut Landing No. 12, in base of power pole 3/8; spike marked " — 0 " (below sea level) —0. 060

Middle River, 3 miles northeast of, at Empire Cut Landing No. 12, in base of power pole 3/9; spike marked *'0 " 0. 256

Tnle weit aloii Atchison, Topeka Sc Santa Fe Railway to point 8 miles east of

Antiooh.

Tule, in front of signboard; top of rail 11. 3

Middle River, in front of station; top of rail 16. 1

Middle River, at southeast comer of cannery; iron post stamped ''B 1907

3,3" 3.292

Orwood, in front of station; top of rail 13. 8

Werner, in front of signboard; top of rail 12. 0

Bixler, in front of signboard ; top of rail 15. 0

Bixler, 200 feet southeast of signboard, at road comer, 20 feet east of section

comer; iron poet stamped "B 1907 15 4" 14. 322

Knightsen, west end of station, 40 feet south of track; iron post stamped

"B 1907 27 5" 26.460

Oakley, in front of station; top of rail 18.4

ly quadrangle; Knlglits Landing, Lincoln, Harcnse, Nicolans, Pleasant Orove, Bocklln, Boseville, Sheridan, and Vexnon 7Y quadrangles.

Colusa, Placer, Sutter, And Yolo Counties.

The following elevations are based upon results of precise leveling along the Southern Pacific Railroad published in Bulletin 342.

The leveling in the Dunnigan quadrangle was done in 1904 by C. H. Semper and in 1908 by W. H. Monahan; in the Marcuse, Nicolaus, Knights Landing, and Vernon quadrangles in 1904 by Semper, in 1905 by G. C. Douglas, and in 1908 by L. F. Biggs and Monahan; in the Lincoln, Pleasant Grove, Roseville, and Sheridan quadrangles in 1908 by Biggs and Monahan; and in the Rocklin quadrangle in 1908 by Biggs. The work was done in cooperation with the State.

Dxtitnioah 16' Qttadbakole.

Honhey toutheait alon Southern Padflo Ballroad to Tolo.

Herahey, 50 feet west of track, at road croedng, 50 feet north of Colusa-Yolo Feet

County line; iron poet stamped "137 B" 137.126

Dunnigan, 60 feet north of station, at edge of park fence; iron poet stamped

"67 B" 67.018

30 SPraiT LEVELING IN CALIFORNIA, IW7 TO IBIO.

Dunniiinin. 3.2 miles iiu1h at, 50 feet eaxt of milcpoet 101, (iO feet east of

tnu-k, at rood crwBiug;iron paelsUmpcd "45 B" 44.955

Ztmun (Blacks Sbdou pat office). O.H mile nf, 0,2 mile south of milppnst 9S, Mat of track, at cothgt of fonte on right of way at public roiid

cnmiiig, vec. 17, T, U N,, R, 1 E.; iron post stamped 45.&41

Rond> nlftlion, east of track at comer of rit of way fence at road croeBing

ear milpa't 94.7; iron post elamped "54 D" 54. 193

CoDac* oatbMKt and Matb to polat aaai ObbbIbui. JTohii'itHchuul, 1.1 niili.'p north tou'eat southeast angle of rrotBroade; iron

pnet tHampiHi "43 li" 43.017

Spanish ranch houso. 1.6 uiilea north o[, south fide of county lice, Ht

nlraore to ranch; iron post stamped "47 B" 47.024

Tcimbrey man's ranch, at fence line, noftheaet angle ol road to north; iron pout Blamppd ' U " 35. 702

San HiBH caub Tia Hawaii Point to Boaik and Kaadr LaaAUt-

Wilkins Slouch school. at weet end of fence, road in front of whonl; iron

post Hiam pod '32 fl" ' 32.140

Wilkine RIoufih Bchool, 2.3 miles south o[, at road lo J. M. Miller's ranch

house ; iron post stamped " 34 B " . . 34. 163

Bowellfl Point, entrance to landing, YoloColuna County line; iron poet

stamped "37 B" 37.383

Howells Point. 1.8 miles south of, gal leading to Bni Miller's nnchbouee;

iron post stamped "31 B" 31.071

Rough and Ready Landing, at junclioo of canal and river, south mde of

canal, 40feei wel larECoi' tank; iron poo t ii tarn pod "40B" 40. fi33

Enlchti T..iiiiii.f wait 4,8 mtlM. tbtUM nottta to KoDth and Raadr lAiuUsf .

Blacks Station post otBce, 4,3 mileaeast of, at croesroadstn Yolo and Grimes

Landing, northeast comer angle of roads; iron post stamped "41 B" 41.177

Zamora (Blacki Station poit oBln) eaat 4,1 mllai.

Blacks Station post office, 2, -5 miles cast of, at comer of gat 10 bareyard of

F, Rchliemann'H ranch house; iron post stamped "49 B" 49.093

Dnnulisa lontbwsit and tontli alonf coniitr road to paint d*u Brlialaj raacb.

Brimley ranch, 1 mile north of, summit between Dimnigan and Fairview f-h'>olhoiise,eat side of road; iron stamped "33,1 B" 333.203

Point a,S mUsi wait bj 1 mils north of HarcaH Tla ElrkrUla to point aeu Snttai School.

Kirkvillc, 2,5 mitefl south of, 3 miles north of Sutter schoolhouse, at angle in road et east side, 500 feet south of deserted building, where road turns east from river 0.5 mile in angle of road and north again 2 miles south of Perrj- Hyatt's place; iron post stamped "Prim, Trav, Sta, Ko, 160 CAL 1908 33" 32.860

Sutter schoolhouse, in county road, 2 feet from fence near northeast comer of schoolhouse yard; iron post stamped "Prim. Trav. Sta. No. 161 CAL

1908 36" 35.744

SlikTiUa north road to point S.B mllea north of Salem School.

Kirkville, 2 miles north of, eaat of road which passes through small grove of oak trees, 0,5 mile south of Mr, Correll's place, at base of small oak tree; ironpostBtamped"Prim.Trav, Sta. No, 2001908 28" 28.258

Pbimaey Leveling. 31

Salem school, 1.4 miles north of, on east side of road, under large black-oak

tree, 2,000 feet north of H. Poffenberger's place; iron post stamped Feet

''Prim. Trav. Sta. No. 210 C AL 1908 42 " 42.411

Knights Landing, Marcuse. Nicolaxjs. And Vebnon 7}' Quad-

Bangles.

Roui;h and Beady Landing southeast along rtyer road io hts Tanidliig station.

Derby Camp, 1.3 miles east of, north edge of river levee, Chinese

camp; iron post stamped '' 39 B " 39. 432

Knights Landing, bridge over Sacramento River, top of south abutment, south end of west wing wall; aluminum tablet stamped B " 41. 553

Knights Landing station, 30 feet east of track, at comer of road, opposite

north side of station; iron post stamped "32 B " 31. 825

htt Landing touth along rlTer road to Grays Bend.

Knights Landing, 4 miles southeast of, west side of road at foot of levee, south line of Mr. Roseberry's place; iron post stamped "30 B " 30. 132

Grays Bend east down rtyer road to Elkhom weir.

Knighta Landing, 10.6 miles southeast of, 0.25 mile north of Doyle's house, 40 feet west of junction of river road and lane, north side of road; iron post stamped "29 B" 28.958

Point near Blego northwest to Byan, thenoe north to Pleasant Grove station.

Sankey, 2 miles southwest of Northern Electric Railroad station; Ryan triangulation station, 20 feet northwest of windmill; iron post stamped "34 B 1908 B.E.I" 34. 564

Pleasant Grove, Northern Electric Railroad station, east of track, west of road, at fence line, 10 feet south of power pole; iron post stamped "32 B 1908 B.F.I" 31. 975

Pleasant Grove station north 7 miles, thence west via Nloolans to Chandler.

Alamos, in front of station; top of rail 35. 1

Striplin, 100 feet east of station, east of right of way, at fence comer; iron

post stamped "33 B 1908 B. M. I ". 33. 359

Nicolaus, in front of station; top of rail 41. 9

Nicolaus, southwest corner of yard; iron post stamped "33 B 1908

B . N I" 32. 864

Nicolaus, 1.4 miles west of, in center of road, in base of 48-inch oak tree;

spike with aluminum tag stamped " 31 B. M. 146 " 30. 72

Chandler, in front of station; top of rail 36. 6

Chandler, 0.1 mile south of, opposite milepost 106, 6 feet east of track;

iron post stamped "36 B 1902" 36.227

Forks of road 8.8 miles northwest of Biego west to Verona School, thenoe north to

Nicolaus.

Verona, 2 miles east of, Barney Mound triangulation station; iron poet stamped "35 B 1908 B. R. I" 34. 899

Verona, 1 mile east of, southwest of road, 150 feet south of warehouse, in base of 30-inch oak tree ; spike with aluminum tag stamped " 33 B . M . 153' 33. 55

Verona, 25 feet north of northeast comer of schoolhouse, at fence line; iron

poststamped "28 B 1908 B. P. I " 28. 592

McNamara ranch house, 1.2 miles southwest of, 75 feet north of Mahon's dairy ranch, at section line, east of levee; iron post stamped "38 B 1908 B. O. I." 38. 3K)

F

Spirit Leveling In Caufounia, Iiw; To 191D.

UcNanura lanch hoiian, Imt wrai of, mUi of n.wd, ai fpuce; inin pct Btiiitipl"40.2"(U. S. E. I>, bwiehnuu-k No. 37)

Niiulatw, 3,2 niilus MHithwMl ul, suuUi of river ruui], in boae of 3((-iiurh coIWdwixicI epic wilh aliimiiiuni xtiimpcil "27 B. M. H9"

Wbcadiind, 4 aiiies south by 4.S miles went uf. north of road, 300 feet nonb of inletsBClioa of roads; iron post dUoiped "59.9 B. M. 27 " M, '

Bir RiviT Bridge, 1.1 mileeBoulh of, 250 feel west of Weeleni Pacific Rsilwnynt bond of road, bI fence line; iron poet stamped "*7.5B. M. 21" 43. Ml

Bunr KiviT Bridge. 150 feet Dor'.h of, east of mud, at fence line; iron poet

stumped "IGB 1908 B. B. 3" m.m

Point 4 bUu wut by 1 uUm north of Ktimt to Itanuc.

Marciue, 2.0 miles west by 1 mile north of, at sou tweet comer of croeeroade;

iron [HiHtfltainped "31 1908" 31. 30S

Mari'iise, 0.4 mile north of, on west side of railroad at fence line, 5 feet naitb

of milepoel lOS; iroci post stamped "33 B 1902" SIK*

Murciise, 5.S miles vcel by 1 niilo north of, went of road, 300 feet west of

levee, driven in ground; iron peg marked "25" J

l.t Biaei norUieiLit of Klrlrrllte.

KirkvUle, 4.S miles of. month of ftad in tule swamp, standing out prominently; iron post stamped "22CAL1908" 2

point BUT fiattsi School to Knlchti LuiiUii(.

KiiiRhtR Tjindin, 2.6 miles north of, on eaeteide of river road under btack- -nlniit tree, 1.200 feet north of white homie with yellow-green roof; iron IHwt stamped "Prim. Trav. Sta. No. 142 CAL 1908 35" 34.748

KuiKhls l.aiidiMc, at railroad station, 30 Feet east of track at corner of highway and on line of north side of Ptalion; iron postBtamped "32 B 1902",. 31.825

o old taDroad

I'haniller, 3mileiitumth of, on westiiidc of railroad, 10 feet from lick, oppo- mIio milepofltioa; iron postBtamped "38 B 1902" 38.006

2.6 miles west by 6.2 miles southwest of, at north end of abandoned Ireallo of Southern Pscilic RaihNid and at south end near center iif old RTade, near end of line of willow treea; iron post stamped "22 CAL 1908" 2L468

Mnrcuse, 2,6 miles west by 5 miles south west of, in hape of tree on west side of old gnido railroad bed; spike with aluminum lagsfaroped "22" 22. 13

Mnrcuse, 2.6 miles west by 1.9 miles southwest of, west of old railroad bed; iron pen driven flush with Rround, marked "26" 26. 17

Marcuse, 2.6 miles west by 1 mile southwest of, weston old railroad bed; iron peg driven flush with RTOund, marked "27" 26.91

Point S. mllti woit b; 1 mU north at Kuoius lonthwnt SM mllea (donbltipni Um).

Yuba City, 16.6 miles southwest of, on levee about 3 miles west of Marcuee, near old cabin, iron post stamped "Prim. Trav. Sla. No. 305 38 CAL 1908" 38.402

Pbimary Leveling. Ss

LnfCOLK. PLEASANT OBOVS, R08BVILLE, AlTD SHEBZDAIT 7}' QTrAX>-

Bakoles.

Wheatland toatheaft aloii Southern Padlio Ballroad to BoMfllle.

Sheridan, 300 feet south of station, northeast comer of brick warehouse; iron Peot.

post stamped "114 B 1908 B. E. " 114. 007

Sheridan, 2.7 miles south of, east of track, 10 feet east of milepost 123; iron

post stamped "HOP. B. M. F." 110.016

Lincoln, 2 miles north of, east of track, 15 feet east of milepoet 120, at fence

line; iron post stamped "141 P. B. M. G." 141.458

Lincoln, 30 feet east of track, north end of station; iron post stamped

"163 H" 163.197

Lincoln, Burdge Hotel, northeast comer of concrete sidewalk; aluminum

tablet stamped "167 I" ', 167.687

Lincoln, 3.9 miles south of, east of track, in fence line, 20 feet northeast of

milepost 114; iron post stamped "124 K" 124.188

Roseville, 3.5 miles north of, east of track, in fence line, 20 feet northeast of

milepost 111; iron post stamped "131 L" 131.589

Roseville, in northeast corner of school yard; iron post stamped "159

B. B. M." 159.936

Roseville west alone road to point near Blego.

Roseville, southeast comer of brick church, 4 feet above groimd; alumimiin tablet stamped "159 N" 159.661

Roseville, 2.6 miles west of, north of road, atRoeecrest, 50 feet west of liveoak tree (forked) 24 inches in diameter; iron post stamped "153 0 " 153. 819

Roseville, 5.9 miles west of, north of road, on summit between two drains; at fence line; iron post stamped "103 P" 103. 272

Roseville, 8.6 miles west of, west of road, 20 feet east of road junction, 3 feet south of fence; iron post stamped "63 Q " 63. 609

Riego, in front of station ; top of east rail 43. 8

Riego, 500 feet southeast of Johnson ranch house, at bend of road, south of road, 10 feet west of telephone pole; iron post stamped "40 B 1908 B. C. 1" 89.964

Johnson ranch house, 1 mile northwest of, eaat of second-class road, in base of locust tree; spike with aluminum tag stamped "32 112 " 32. 344

Roseville northeast along Southern Padfle Ballroad toward Bocklln.

Roseville, 2.1 miles east of, north of track, in base of milepost 110; spike with aluminum tag stamped "201 96" 201.49

Pleasant Orove along road east 4 miles, thenoe south to crossroads 2.6 miles east of

Blego.

Pleasant Grove, at road junction, 75 feet northwest of hotel, 15 feet east of

windmill, at fence comer; iron ])()8t stamped "47 B. 1908 B. G. 1 " 47. 516

Pleasant Grove, 2.7 miles east of, in northeast angle of second-class road

junction, 5 feet eaat of fence comer; iron post stamped "75 B 1908 B. H.

1 " 74. 792

Falconer ranch, 1.9 miles south of, west of road, at section line; iron poet

stamped "64 B 1908 B. I. I." 63.617

Forks of road 7 miles west of Roseville north and east, thenoe north and weit to fofln

of road 2.7 miles east of Pleasant Grove.

Roseville, 5 miles west of; Kaseborg triangulation station at west end of cabin; iron poet stamped "106 B 1908 B. J. 1" 106.153

Pleasant Grove, 250 feet west of schoolhouse, weet edde of road, at fence corner; iron post stamped "106 B 1908 B. K. 1" 105.662

95094— Bull. 481— U 8

U SPIHrr l,KVKUNO fN (-AUFIIBNIA, 1907 TU IWO.

HMiftat Otom botU bIbsc iad IJ* nlM. tut 1,T hUm. ud BOMh te trfcriHBM

PlriiwiDt Gnivti, :l.". mil iwrlli "f, west of mwi ul itileiwctifin iil l.VJ foot of house, in EuutlitOKt eiirner of lot; imii pct tilaiii|>ed "50 B

1908 U.X.I" saiw

Gmve, 7,1 milw iiortheaat of, south of mad.atintPrawtionofrtiMla Dt iHiint whom line tuna west, 25 feet nartfa of gM: una poet stamped WBlMaB. V. 1" 5,877

IVhraiUnd, 4 miles soiilh by 3.7 mJlsB weat of, anutii of fowl, at fnieraecdoo of rouiU where )>owiT line limit snuth, 25 Icei met of power polw 34-£l>.' in.ri |wlBUunpl"61BI908U.2. 1" 81. 8N

WliKHllanJ, 4 niilM auulli ot. niudi rawj, at iuleTBeclion of roads, 25 font wi'sil of pilv, mhmo jKtvuT lino Mms wMt, 50 feet amity of pnwitr pnl 31 if'n pot atampeff "B2 B ia08B. A.2" IW

U'biwlhux). 0 5 milo ioulh of, nu* of maH. al f3ii lino; iron past stamped "83,8 B. M.4S'" (Unilod SutesCorpnolAnuyEngiijww' D. M. 48)

Toiki ot road* t J mili* botUi or Plaataat Sran wMt aloac road.

Whtttlland, 4 luilcsiiKudi by 4.7 iniliH wcstof, suuthot rmd, atinlereectioD mail from unrth, at lino, in base of fence post; spike wilb aluminum tag Btaroped "56 B. M. 188" jja

ToAi ot road* I.* nlla* nacth ol Flaaaaat Ordn aaat to *''

Liurnln, 4.4 mil™ wost siiilh I'f rigid at road at fence comer; iron post stamped "KM It I!n8 B. !.. 1" Hit Stf

Pteuast Orot* aortkaut and doiU to (snroadi 1.1 sillei wart ot UbooIh. Pli'U.sint drove, (l.fl milcH nortlicatiC of, at northeast comer of intersection of Miuis; iroiip,v-t.-tania>-'rl -'UH B 1908 B.S.I"

Uncoln BOrUi alone road t.B mllaii thaaae wait to Shwtdaa.

I iiii'oln. :l.4 iiiilfi" ii'irth of, at iiorlhwest corner of mad iutereection; iron |..i-( -174 I'AT. MKIS" 173.900

I iii.-'Iri. 1 niilr' nurih "f, nt nonheaat corner of T road east, on top of

I in<-o1ii. (i.(i nilli'ii niTlli of, 4. miles eat of sheridan, at nortbweet comer ,it pw.l iiii.'rsii'li.iii; imii iio:-t "2.J8 CAL 1908" 258.593

."lioiiilun, - iiiilos i';W of, at wmiheast corner ot bridge over small stream, l.'.i f.'.-i i'sl I'f T ro;iii ninh, in jiopt ; sjiiko with aluminum tag stamped Ml.-" 117.66

)>alBl Beat WheBtlaBd wait 1 mllai to SbarldaB.

lii'iill;io,l, I niili'.-< oiisi north nf road, S<)0 feet east of intersection of i.,l.. Ill li'u.e line: ir-.n clumiMil "78.2 It. M. 49" (United States r..ii ol .\ruiy KnsiurtTs lu-ni-li 74. 536

i. Hanstc Depanmeal.

Pbimaby Leveling. 85

▲t KoekUa.

Rorklln, 60 feet northeast of station, in foundation at southwest comer d Feet, roundhouse; aluminum tablet stamped "244 B 1908 B. 244. 429

Browns Valley, Oillsizer Slough, Grimes, Harysville Butte, Heridlan, Ostrom, Smartsville, SpencervlUe, Sntter, Tisdale Weir, Wheatland, and Tuba City lY quadrangles, and Smartsville special quadrangle.

COLISA, NEVADA, 8tTTEB, AND YUBA COUNTIES.

The elevations in the following list are based on the results of precise leveling along the Southern Pacific Railroad pubUshed in Bulletin 342.

The leveling in the Grimes, Marysville Butte, Meridian, and Tisdale Weir quadrangles was done in 1904 by C. H. Semper and E. M. Fry, in 1908 by W. II. Monahan, and in 1909 by W. H. Barringer; in the Gillsizer Slough, Ostrom, Sutter, and Yuba City quadrangles in 1908 by L. F. Biggs and Monahan, and in 1909 by Biggs; in the Browns Valley, Smartsville, Spencerville, and Wheatland quadrangles in 1908 by Biggs and Monahan; and in the Smartsville special quadrangle in 1908 by Biggs. The work was done in cooperation with the State.

Oillsizeb Slottoh. Obtbom, Sttttzb, Avd Tx7Ba Oxtt 7}' Qttad-

MarysvUle north by Boutkem Padflo BaOroad aad Mwt alone road to Bvnmlto

Hooae.

Marysville, 225 feet west of track, at southeast comer of railroad park; iron PMt.

post stamped *'61-B 1902" 61. 202

Marysville, 2.5 miles north of, south of railroad, at fence line, 5 feet north

of milepost 145; iron post stamped "65-1 " 66. 400

Marj'Sville, 5.7 miles north of, 50 feet south of railroad, at fence comer, 800

feet north of milepost 148; inm post stamped **73-2" 71. 896

Sevenmile IIousc*, 3 miles west of, at northeast comer of bridge over

Nigger Jack Slough; top of painted bolt with aluminum tag stamped

"75 5" 74.43

Sevenmile House, 2.3 miles west of, northeast comer of granite milepost;

notch marked "80 6 " 79. 45

Sevenmile House, 1 mile west of, east of road, 50 feet north of junction, 5

feet west of power pole; iron post stamped "90 3 " 89. 724

Point 1.3 miles south wett of Brophy School west to Maryivllle.

Brophy school, 1.2 miles southwest of, south of road, north of fence, opposite house on small rise; iron post stamped "84 21" 83.815

Mar>'svillc, 3.7 miles east of, north of road, 5 feet north of fence line, 1,000 feet northwest of house on mound; iron post stamped on rim "74.8" (United States Corps of Army Engineers* B. M. 71, their elevation 74.8 feet) 70. 236

Marysville, 3.2 miles east of, north of road, at fence line, opposite house; iron post stamped on rim "U. S. E. D. 75 " (United States Corps of Army Engineers B. M. 73, their elevation 75 feet) 70. 323

Looally known as U. 8. Sogioaer Dtpartmnt.

Spirit (.Kvfojso In Cai-Ifornu, Imt To 1910,

Muyivillf. 2. miW Miiillit<(ut uf. ai uurthwiwt I'onier of craeniMMb; iroa

pusi oumpMl "SS CAl. ItKiN "

UATjaWUc. 1,3 iiiHiw o(. on (iliue ai ntirthwrt cumur o( T rod'

chiwlpd muiiri'; aluminiini tui; "05'"

MuTfTlU* loot BontbwB pmeUke BaUrokil to OlbOB. Uarir'BViUe, 2.1 mili-n bkuMi "f, .W teet caat nf mUepOHl.laB, At fnDc, met nf

lnM!k; iron tampnl "81 B 1908 A. B,"

Mar}-still, 5 7 milfvi wiulh o(. east o( ick, 40 fst of miliiM I3G. nt

PolBI BMW PloBM Scfaool WHt to KuTMlk rw4. tfcM wiaa. Itt-ur lUvi-r Bfidgt-. a, 7 niili?? north of, cast nf ruurl, ul inliTwvtion ul ruwl

l( UKlH B.r.S"

Ili'Mf Rivt-r Bridje, 2.i luiW iwrlb of, eoiiliiMuiI corner til bridg* "'pr hdiuU

rri-i'k; lo|) of bolihcait and aluminum tag fltiimiH'cl "46 18V.

Ilownnl, 1 mile Boutb of niutiun, SO (wt eaat of Norlheni Eleciric tUilrtwd right of way, at. bond r>( vaA. in feTi<*e comer; inin poet itampMl" o3 B

1908 B.D.U"

41.L'96

MaryevtOe, 0.9 mile mtith of station, west of mind, at fence line, 5 levt

north of mileiKiel 121; iron post k turn ped '6S B 1902""

Yiiba('ily,3.4 raileHwmthwestof, in southeast comer of Lincoln Bchoolyard;

liruiit Si'hiHil, norlhwoKt corner uf yard, at crossroads; iron poet slumped

I'rini. Tniv. Sla."

(.ininr SrhiKil, IS.'i niiltw siiuth nf, in wmthwest comer of bridge over pond;

iiip ijf bull with uluniiiiiim tag riiamped "36" ;W. 0".'

(ir.irif Srhoiil, -I.S mill's with of, weft of rid, 150 feet north of Christopher-

.-i'li's ranch huiw; irnn posi staraped "35 <.'AL 1908" :ti. 3KI

It aloBC road ta fork of rouli

City.

miles sinilb by 0.5 mile east of, iu east comer of junction uf T

1 piB-t stump'il 44rAL 1908" 43.656

by 2.2 mileHea.'(of,inculvcrt over road; spike vrith

lui: sl:ii.ip.-d 46. 14

riiilo,* mniih by 3.5 miles cast of, in northwest comer of

V viird; iroiitiKwltiiamped "50('AL 1908" 50. 171

2 iiiili's by 4.5 miles east uf, north of road, in front of .Ki\ 111 bii.it of Inv; spike u'ith aluminum lag stamped "51".. 51.39

tltnat SPkool WMt and north toward SnttBr City. , .1 null" tt iwt i'(, Bi'si of roiid ul fork of road from north ; iron

.f, (H) fot'l northeast of jui II |Nci Htaniiied B 1909

Pbimaby Leveling. 37

Wooddrift BchoolhouBe, 0.4 mile west by 1 mile north of, center of road, in Feet, base of 36-inch oak tree; spike with aluminum tag stamped "72 B.M. 3 ". 71. 81

Wooddrift schoolhouse, 2 miles north of, 300 feet south of section line, west side of road, in base of 40-inch live oak tree; spike with aluminum tag stamped "75 B.M. 4 " 74. 78

Point 7.1 miles northeast of MarysvOle northeast 10 miles, thenoe west to Honcnt

(portion of line).

Nigger Jack Slough, 3.2 miles north of, southwest comer of intersection of east-west road; iron post stamped "95 B 1909 B.T.'* 94.609

Yuba City west along county road to Sutter City.

Yuba (ity, 3.8 miles west of, north edge of road, at section line west edge

of ditch, 30 feet north of bridge; iron post stamped "53 B 1909 B.K.".. 52. 831

Sutter City north, east, and north alone county road 7 miles.

Sutter City, 1 mile north by 1 mile east of at section line, west end of large gate to second-class road, in base of gate poet; spike with aluminum tag stamped "56 B.M. 40 " 56. 94

Sutter City, 1 mile north by 2 miles east of, north side of road, southeast comer of grove at intersection of road to north; iron post stamped "53 B 1909 B.L." 53.494

Sutter City, 2 miles east by 2 miles north of, west edge of road, in base of 40- inch oak tree; spike with aluminum tag stamped "57 B.M.41 " 57. 27

Sutter City, 2 miles west by 3.1 miles north of, 0.3 mile south of Union schoolhouse, west edge of road, 200 feet north of dry creek, in base of 20- inch oak tree; spike with aluminum tag stamped "62 B.M. 42 '' 62. 70

Union schoolhouse, northeast comer of school yard; iron poet stamped "66 B 1909 B.M." 65. 856

O&OESS, MARYSVILLE BUTTS, KEBIDIAN. AlTD TISDALE WEIH 7}' QUAD-

Bakoles.

Colusa southeast to Sycamore.

Sycamore, at east margin of highway, opposite saloon, between locust trees;

ironpit stamped "48 B" 48.129

Forks of road 8.7 miles south of Sycamore south and west to Arbuokle.

(Jrimes Landing, northwest comer of Main and Second streets; iron poet stamped "47 B" 47.089

Sam nines' ranch, in northwest angle of roads; iron post stamped "32 B ". . . 32. 108

Sam nines' ranch, 2.6 miles west of, 145 feet west of levee, south of road;

iron stamped "26 B" 25.932

College City, 1.5 miles north and east of, 1,100 feet west of bridge over slough, at southeast angle of road to south; iron post stamped "36 B ''... 35. 824

Point 3.6 miles north of Salem School northwest via Eddys Ferry to Meridian.

Eddys Ferry, 4.5 miles southeast of, at west comer where road turns at an angle of 90 degrees to right; iron post stamped "Prim. Trav. Sta. No. 215 CAL 1908 41" 41. 089

Eddys Ferry, 1 mile north of, on top of levee, in dredge cut, 500 feet west of road and 300 feet north of residence of Gerdine's dairy, first house on left side of road from Eldys Ferry; iron post stamped "Prim. Trav. Sta. No. 222 CAL 1908 47 " 46.554

Eddys Ferry, 3.4 miles northwest of, in front of large red brick house, in base of fig tree; spike with aluminum tag stamped "49 " 48. 93

' SPIRIT LK*EU!CO IS CALiroKMIA. tSCTT TO IBIO.

afidlaa. 2.3 mllM aMitb ol, hMv ii( hn-n-, wwt ndo trf trmi. ISO ImI

nuth at C. D. C'rookMi'c lunw!; ban pot Mapped " Pritn. Tiv. 8tk. Nn.

aa? CAL itweBi" aq Tij

rridutn, W. WawJ'sywd, iAtaMctknolcountj- iDrnliMUid buryroMl; iruo )HBtatuiiped "Prim. Tisr. Su. No 200 CAiL 1W8 61"

MwldUa MM M ilitaii SMtar CKT-

pridian, nf, in baup of Iver on BatlvSlou.niatii of mait. ill iiii|:li> oppupiU'An'l houM from Slough Bchoolboiwe; iran piM

Prim.TrBV.Sia- No. Sfi&tTAL 10S*S" -(.VlM

liter Clly, un ouiheMt of Colunaud Acarii meetH. ii Uw curoer lit ClpDifnt'* bftrayurd; iiun poet stamped "Prim. Tmv. S*x. No. STT CAI, 1D08 07"' - IT II

null SriKiul, 2,6 miU-M wwt vl. ilitiicv 3.6 miltit n.>ulbireBt of . outli uf ill liiUi aWBinp, 300 feet iiuitlieaal uf sntBlI allie; iruo pit iilsiiipcd ":hi IIRWCAL"

Mt SJ oUlH wut ot Mnldua aarUiinit nd mu( idosc Ugkintf lo PnabrU''

Wwl Butw, 3.1 nillfH Miutlioiut of, lower side of rud. ou bowlder; iliiapl Ijoiiil pkiiitnd U.S.H.M.Isr'

Wmi DuIU, O.d milv <4Ul by l.S niileH aoutb of. iu fiunt of Taik'HUiioJi (whlu tatum), caat Nida of , in bowlder; afurainum tablet Htuoppd -M 1000 H,V,"

\V<-Mi Itititi', \:.'2 mtli'H nurtli of, north side of road. SOOfeeteast of abackson hillKiili' iiliiiv.' 15 fi-'t iiorlh uf center of roadway, in bowlder; aluiiiiiMini liilil.'i (Jliimpfri "(17 H 1909 B.W."

N'nyi'sliinx, 1.1 riiili'H iiordi liy 0.3 Diileeaot of achoolhoiiso, easteide of mad. IIHI Ti-r'i fiiiiili ,,!' while hoiiM-. uii lop of email knoll. 5 feet weat of eaet Iriiii' hill' iihuii; riiii.l, ill larp' IwiwMer; aluminum tablet Ktamped "*71

Ciihiiiii <'<iiiiity roiirlliiiitM', 2 mil<>a noutheatit of, eaI aide oE road, ill liiin-iit 'l-tiii*li Hyiiiinore In-e; iiippcr brad with aluminum tag stamped

inlli'H Hiimlienxl of. enol Hide of levee road, 0.25 mile soulheaHt of (iiriiihniisi', 2 iiiili-s iinrthweat of Kent, 2 feet north of telephone pole pniiiK'd ' r. S, 11. M.;" inin iwt stamped "58 B 1909 H.T."

I inileH iiurilK'aKt of. 0.:t inileKiniih of Kent, eiist tiide of road. in nf hniwn lioiiHe and KM feet north of eiitninee (o j-ard; trunpoat Miiinii,.d -M It 1!KI!J It. X,

Meriiltan. :l.l mitcH north of, 1.2 miles of Kent, east aide of road, in flint uf white lumse, in base of large tig tree; spike with alui Ntanipeil "ri4 H, M. 57"

Valon tchoolboaM Kiatli kloiic Utbinr to CoIdw Iportloa of U

(Vilnsa. north wall of Ciilnsa County eourthoune, 15 feel went ui trance julnminum tablet stamped "60B 1904"

Primary Leveling. 39

BROWNS VALLEY, SMARTSVILLE, SPSHCERVILL AVD WHEATLAKD ly QTJADRANOLES AED GREATER PART OF SMARTSVILLE SPECIAL QTJAORANOLE.

Serenmlle House eait by road to Parki Bar Bridge crossing rarer, thence southwest by road to point 1.2 miles southwest of Brophy school.

Sevenmile House, 1.6 miles east of, 50 feet east of junction of road, 10 Feet,

feet north of telephone pole, north of road ; iron post 143 4 . . 143. 088

Sevenmile House, 4.5 miles east of. 500 feet east of road junction to Brown6 Valley, north side of road, 150 feet west of dwelling, in bowlder; aluminum tablet stamped 191 5" 190. 921

Sevenmile House, 6.3 miles east of, west of road, 50 feet east of junction of road, in base of 36-inch pine tree; spike with aluminum tag stamped "247 12" 246. 46

Barrier No. 1, 0.3 mile northwest of, 18 feet south of section post 14, 150 feet north of Yuba River; iron post stamped *'204.7'' (U. S. E. D. B. M. No. 26) 200. Ill

Barrier, on top of north abutment; chisel point painted 220 14 " 220. 14

Barrier, 0.7 mile southeast of, 400 feet southeast of draw, 400 feet from bar gate, north bank of river, 600 feet south of cabin on knoll, 10 feet north of river, 5 feet south of wire fence, on rock; chisel point painted "214 ". . 213. 69

Parks Bar Bridge, 1 mile southwest of, south of road, 20 feet south of bridge over small creek, in base of 24-inch white oak tree; spike scribed and painted "266 B. M. 42" 266. 49

Brady ranch, 0.3 mile southwest of, north of road, at summit of rise, 15 feet north of fence, in country bowlder ; aluminum tablet stamped " 349 18 ". . 348. 486

Heigson 's ranch, 0.1 mile southwest of, north of road, 15 feet south of fence, on summit of rise, in country bowlder ; aluminum tablet stamped " 227 19'* 226. 831

Lane ranch, 200 feet north of house, north of southeast comer of corral; iron post stamped "97 20" 96.824

Ostrom southeast along Southern Paoilio Railroad to Wheatland.

Ostrom, 2,3 miles south of, east of track, 5 feet north of milepost 133; iron

post stamped "71 B 1908 B. C." 71.242

Wheatland, north end of railroad station, 5 feet east of telephone pole; iron post stamped "86 B 1908 B, D." 86.104

\Mieatland, water tower, northwest corner of granite foundation; chisel

point ; iron foot plate stamped " 91 B. M. 61 " 90, 71

Wheatland, in front of north end of station ; top of rail 85. 8

Wheatland north to fork of road 2.1 miles west of Brady ranch.

Wheatland. 5 miles northeast of, at northeast corner of T roads, near comer

of fence; iron post stamped " 101 CAL 1908" 101. 052

Earle. 300 feet southwest of schoolhouse, at southwest comer of crossroads;

iron post stamped " 116 CAL 1908" 115. 894

Earle. 2 miles north of, at west side of road, 450 feet north of lane leading

U) house on east side of road, on rock; chiseled square marked " 123" 123. 45

Erle, 3,5 miles north of, in southeast corner of lane fence leading to house

on right; iron post stamping "189" 189. 471

Earle west by road to point 4.8 miles southeast of MarysTlUe.

Erle, 4 miles west of, 390 feet west of gate leading to the Boardman ranch house; iron poet stamped "74 CAL 1908" 73.

Spirit I.Eveliso In Taufobki '.

a Hooaty Dai aad tsidc* arwr iiocr iir* lUt it-irth miio nf nwd. 'AU it-M iionh <i( . 10 (eet

.)( lak irw, ill bowlili-r. iilumiiuim tabid, stamped 2al, 9

Purlui ttor Bridge, <in northiauil iibutmi-nl; Uip u( liMlplaU- 244.01

rarluIW Bridjie. im miithtrmt abiilmpnt: lop of timipUUc 747.8

Sumrtm'illu. 1.4 milui north u(. at niirthnun (-tinier o( bridjm ovcrYuha

(>Twk, lop of tfim; (nintnl bolt vith nltiminuRi tagKatnpM "MS 16".. 344 Q Snuirtavlllu': 'iM (put vubi u( auuth of road. 10 fM aouih <if

jiincninii at rtud. on larv bowldtn' ptunll "619 IS;" diiad pint SIS. VI

SinartwiHe, cimior nf porch fonndation to RsrdMi> huu;):

altuninitmUblitMiuiipMl 'SMS"

8niartviUt>. I).S mito aotith nl, raol of at mod jiinrtinn. on

paintml " 792 IB;" diJel point

martavillf, 1.3 tnilo* north (if, cwt n( rand, ino fmt caM of cnMnttde,

liH'l mirth of (litoh nii mtinjiiit. iif hill, in bowlder; adiifninuin Ubt4

sluiiipcl "09 lO"

Polat t.l nil*! w*ft of Bitdc*iK>[t lontb asd wmI atoac baak of Taba to Puki Bar,

Mouth of .South Fork (if Yuba Riv'r. 4.4 inilea aouiltwwi of. aouth butikof rivtr, at Jaincw linr. 2G fiut went of rable ovr rivw, on rock pointed "373 33;" chinnl p-iint -- - - 3?iali

Muulhot South Fork of Yilbn River, 5.7 raileii miilhwil of. opporitediuw. ftnilh sidn of , l.tKKI Icei west of hnm on oppokilp bonk of rivr. 50 fpet wcwlol claim fts.\u\ on nick painll chill point

Mouth of South Fork of Yuba Biver, B.5 milea aouthveHt of, wuthTreel point 01 mouth of dnw, hUt feet wt of dmr, on opposite nde of river, Bti'cp nic'ky jHiiiil, GO feel river in larce bowlder; aluminum ljilili'lliimiH.,l";!5.1 Itj- ;3.865

\tmjilL <if DeiT 1'r.H'k. 2IHt tf.4 rast uf, uii beiicii, cast bank of creek, south Imiikdf Yiilia HiviT, in nf knot iti ao-iiich two-fucked oak tree scribed imd piiiiili'il -H-J!!;!.-!." Kjiik,. :i2K01

Mimth ,if Di'cr I'. il.7 mil.' s.nillnvi'st of, with side of river, upper end nf t;nri.i' ill liciid nf riviT wiei']) bluff undcniemh overhanpnp rix'k. liiiiiilinl JN7;I7;" .liisel pninl L'Hd 47

N:imiW!<. 1.") feel i-.is( nf iinrili ;itii Imniw nf cmIiIc, uli rock aluminum tabid Hl;iin|.,.d 'tlS 17" -.. :{17. 733

Pirkn Kur Kridi-. :.>.<i mile" i-.isi of, nt cud of lou' sand 15 (eel south ijedriH-k painted "259::"

I'iirk.-i Itar Hrid;."i', 0.5 mile i-,i.<i <-i. imrili bank of river, on joint between two draH. 20 fn't norlli of w;i1.t's eilsf. im rock painted "227 41 1" chisel

Point nsar Ifooaer Fl*.t oortbtatt ta BrldEeport, thence weit l.S mUsa.

Mooney Flat, 1.3 miles iinrlhesisl of Bclioolhoufe, nurtli of road. 15 leet south of 3IJ.inch bull pine tree, on bowlder painted ''797 23;" chisel point 795. 03

Mooney Flat, 2 miles northeast of house, south of road, oppoeite

round hill, in lai bowlder; aluminum tablet stamped "1011 11" 1,010.840

-Mooney Flat. 3 miles northeast of. north of road, 50 feet west of end of lane, near top of ridge, on bowlder painted !'11GS24;" chisel point 1,166.78

Primary Leveling. 41

Mooney Flat, 4.1 miles northeast of, east of road, on summit of ridge, bend Feet.

of road, on steep bluff, on large bowlder painted " 1223 26;" chisel point. 1, 222. 72 Anthony House, 1 mile northeast of, north of road, 20 feet east of ditch, on

summit of rise, on bowlder painted 1259 chisel point 1, 259. 20

Anthony House, 1.6 miles northeast of, south of road, at ditch crossing, 600

feet east of cemetery, in bowlder; aluminum tablet stamped 1334 12'*.. 1, 333. 936 Rapps ranch, 0.7 mile northeast of, north of road, on bowlder painted

"1000 30;*' chisel point 1,000.305

Bangor 16 quadrangle; Biggs, Bntte City, Bntte Creek, Cherokee, Clear Creek, Dayton, Dry Creek, Durham, French Crossing, Gridley, Honcut, Keefers, Nelson, Newhard, Nord, Oroville, Palermo, and Pennington 7Y quadrangles.

Butte, Colusa, Glenn, Sutter, And Yuba Counties.

The elevations iii the following Ust are based upon the results of precise leveling along the Southern Pacific Railroad pubUshed in BuUetm 342.

The leveling was done in 1909 in the Biggs, Butte Creek, Butte City, Cherokee, Clear Creek, Dry Creek, Dayton, Durham, French Crossing, Gridley, Honcut, Pennington, Palermo, Newhard, Nelson, and Oroville quadrangles by Tj. F. Biggs and W. H. Barringer; in the Bangor, Keefers, and Nord quadrangles by L. F. Biggs.

The work was done in cooperation with the State.

Bavgor 15' Quadrangle.

Point 7.1 milei northaait of MarytvUle, northaait 10 milan, thanoa watt to Honcut

of Una).

Honcut, 4 miles southeast of, south end of large gate, at second-class road to Honcut, 150 feet north of house, west edge of road; iron post stamped Feet. *'119B 1909 B. U/' 118.719

Honcut Greek, 1 mile southwest of, 10 feet east of road, 1,000 south of Bryden ranch house, on 3 by 2 foot bowlder; chisel point painted 158 B.M. 69" 157.65

Honcut Creek, 0.7 mile south of, 0.5 mile north of Bryden ranch, at junction of road to east, west side of road, in base of 24-inch oak tree; spike with aluminum tag stamped 208 B. M. 72" 207. 96

Honcut, 4.5 miles northeast of, Honcut Creek bridge, northeast pier; aluminum tablet stamped "168B 1908 B. W." 168.248

Honcut, 4.3 miles northeast of, 0.2 mile we.st of Honcut Creek, at intersection of north-south road, in basi of stump; spike with aluminum tag stamped '' 194 B. M. 73" 193. 99

Bryden ranch eait 8.8 miles (spur line).

Bryden ranch, 1.3 miles southeast of, 400 feet east of junction of road, 10 feet west of road, in base of 24-inch oak tree; spike with aluminum tag stamped "324 B. M. 70" 324. 20

Buckeye schoolhouse, 2 miles north of, south side of road, on hill above creek, in base of 36-inch oak tree; spike with aluminum tag stamped *'292B. M. 71" 291.80

Buckeye schoolhouse, 2.6 miles northeast of, 2 miles north of Chinn Butte trlangulation station, on first section line east of butte, 20 feet north of load at section line; iron post stamped "334 B 1909 B. V.'' 334.190

42 Spibit Leveling Tn California, 1907 To 1910.

Butte Citt, Butte Creek. Fbevoh Cbossino, Avd Pehhutotov 7'

Blcti weit to PriBoeton.

Biggs, 0.7 mile north of, west edge of railroad right of way, where wagon road turns west, in base of telephone pole; spike with aluminum tag Feet,

stamped "91 B. M. 83" 90.320

Biggs, 1.8 miles west of, southeast comer of bridge over drain, in concrete abutment; aluminum tablet stamped "86 B 1909 B. 85. 967

Biggs, 2.6 miles west of, northwest comer of bridge over drain in top of concrete abutment; spike with aluminum tag stamped "84 B. M. 85' . 84. 57

Biggs, 3.2 miles west of, northwest comer of bridge over Spring Valley Mining Co.'s canal, in top of cord; bolt head with aluminum tag stamped"90B. M. 86" -. 89.84

Biggs, 3.6 miles west of, 100 feet west of junction of road to north, south side of road, in base of telephone pole; spike with aluminum tag stamped "79B. M. 87" 79.44

Bi£g8, 4.7 miles west of, south side of road, at junction of road to north, in base of telephone pole; spike with aluminum tag stamped " 76 B. M. 88" 76. 12

Biggs, 5.4 miles west of, at Landlowschoolhouse, northeast comer of school yard; iron post stamped "77 B 1909B.A.-1" 77.488

Landlow schoolhouse, 1 mile west of, south side of road, 100 feet west of old bam, in base of cotton wood tree; spike with aluminum tag stamped "72B. M. 94" 72.14

East fork of Butte Creek, 0.4 mile west of, south side of road, at section line northeast comer of field; iron post stamped "70 B 1909 B. C. 1" 70. 106

West fork of Butte Oreek, northwest corner of bridge over, in floor; spike with aluminum tag stamped "72 B. M. 98" 72.24

Union schoolhouse, 2 miles cast of, at intersection of north-south road northeast comer of field, in base of fence post; spike with aluminum tag stamped "71 B.M. 100" 70.88

Union schoolhouse, 2 miles east of, northeast comer of intersection of northsouth road; iron post stamped "72B 1909 B. D. 1" 71.900

Union schoolhouse, 1 mile east of, north edge of road, on section line, in base of fence post; spike with aluminum tag stamped "71 B. M. 101". . 71. 65

Union schoolhouse, 200 feet north of, 3 miles south of Butte City, 150 feet north of Marvin Chapel, northeast comer of churchyard, at intersection of north-south road; iron post stamped "74 B 1909 B. E. 1" 74. 161

Union schoolhouse, 1.5 miles west of, 0.2 mile south of, at Flannigan's ranch, in yard, in base of 48-inch oak tree; copper brad with aluminum tag stamped " 78 B . M . 36 " 7 8 . 69

Princeton, at ferry crossing, on east river bank, in base of 36-inch oak tree; spike with aluminum tag stamped "72 B. M. 37" 72.60

Sacramento River, at Prince Ferry; surface of water. May 25, 1909 65.6

Point 7.4 miles wett of north along highway to Wilson (portion of line).

Biggs, 7.4 miles west by 1.5 miles north of, 2 miles west by 1.5 miles north of Landlow schoolhouse, 20 feet south of northwest comer of fence, 0.25 mile west of white bam, in base of fence post; spike with aluminum ta$ stamped "77B. M. 2" 76.37

Landlow schoolhouse, 2 miles west by 2.5 miles north of, at intersection of county and second-class road, 150 feet east of ranch house, 10 feet west of telephone pole; iron post stamped "81 B 1909 B. A.!' 80. 645

Primary Leveling. 43

Landlow schoolhouee, 2 miles west by 5 miles north of. southeast comer of Feet,

field , west of road , at fence comer; iron post stamped " 92 B 1909 B . B . " . 92. 056

Iandlow schoolhouse, 2 miles west by 6 miles north of, west side of road, in base of fence post near gate; spike with aluminum tag stamped B. M. 5" 90. 74

Point 8 miles wett of Landlow schooUionte wett and louth to TJnion lohoolhonse.

Landlow schoolhouse, 2.3 miles west by 2.5 miles north of, 6.7 miles east of Butte City, in floor of Butte Creek bridge; copper brad with aluminum "84 B. M. 27" 84.0:]

Butte City, 5 miles east of, on north side of road, near section fence line, in base of telephone pole; spike with aluminum tag stamped "77 B. M. 28" 77. 056

Butte City, 3.5 miles east of, county road bridge over small slough, white house on west bank of slough, in floor at east end of bridge; copper brsui with aluminum tag stamped "84 B. f. 29" 83. 62

Butte City, 3.3 miles east of, at intersection of north-south and east- west roads, 1 ,500 feet east of ranch house in clump of trees and long barn on north side of road, northeast comer of roads; iron post stamped "80 B 1909 B. M. " 79. 983

Butte City, 2,3 miles east of, at intersection of private road to south, south side of road, in base of fence post at gate; spike with aluminum tag stamped "81 B. M. 30" 80. 72

Butte City, 1.2 miles east of, at intersection of north-south and east-west roads, in fence post which is evidently also a bench mark for some other survey, southeast comer of road crossing; 20-penny nail with aluminum tag stamped "81 B. M. 31" 80. 26

Butte City, at Neleon road entrance, 1,000 feet east of Dr. Gatliff 's dmg store, in base of telephone pole at street comer; spike with aluminum tag stamped "85 B. M. 32" 84. 58

Butte City schoolhouse, opposite, in comer of fences, at south end of blind street mnning north-south: iron post stamped "87 B 1909 B. N." 86. 200

Butte City, 1.2 miles east by 1 mile south of, east side of road, at section fence line, in base of 12 inch by 12 inch post; spike with aluminum tag stamped " 77 B.M. 33 " 76. 31

Butte City, 1.2 miles east by 2.2 miles south of, in center of county road, ' in base of large blazed oak tree; copper brad with aluminum tag stamped '78 B. M. 34 " 77. 65

Union schoolhouse, 300 feet north of, 3 miles south by 1.2 miles east of Butte City, 150 feet north of Marvin Chapel, northeast corner of churchyard, at intersection of north-south road; iron post stamped *'74 B 1909 B . E.-l " 74. 163

Parrott district schoolhouse south along highway to point S.8 miles east of Butte

City (portion of line).

Butte City, 3 miles east by 2.4 miles north of, east edge of road, at second class road to wet, in base of telephone pole; spike with aluminum tag stamped "90 B. M. 75" 87.84

Butte City, 3 miles east of, 1.4 miles north of, east edge of road, in base of second telephone pole south of bridge over drain ; spike with aluminum tagstamped"85B.M. 76" 82.87

Butte City, 3 miles east by 0.2 mile north of, southwest comer of bridge over slough, in floor; copper nail with aluminum tag stamped "85 B. M. 77 " 82. 94

SriHIT LEVELING IN CALIFORNIA. IWOT TO 1I0. B HbODlhmua KXtk loBc Uckwar to Ootu rpotHoB of Um>.

Uoion Bchonlhoiiiv-, 1 mile MiiUh of. in [mnt if Bofhtnt-j-'s , in liOM of FaA

(cinphone spike with ttluminuni lag slampi'd "71 B. M. 3i$" 71. tl

Uniuu HchuulhiniM), l.I* milua truth nf, at Attou pout offioc, nn \nmt adr of cotul, in baae of t1phone> pile; spike with aluminum tag Btampnl

"TOB.M. 39" Tttia

nninn srhnolbouw, 1.& milm twiilh by 1 milo wet uf. 2& feot ittst of east bank of Druui Ki'lipy Sluu){h, wiulh iud of ratA. in bow u( 48-iiii-h oak

--; with aliuniniim togitamped "75 B. M. 40" 74.75

Uoiiiii Hchuulhoiue, 1.5 mileaKxilh by 2 milea weal of, 2 miles weHtuf Afloo piMt iifiice, at intenection of niad ruining south to Coliua, 0,5 tnUe north of Warfleld's , north Ride of road; iron post, eiaroped "T7 B I90B

B. O." T6, T97

AJton, 2 mile* west by 1 mile aouih of post office, croasing of road over 8acramenlu Riv<!r levee, 0.5 mite south of Warfield'sraDrh, east aide of rood, iu btuN! uf telephone pole; spike with aluminum tag stamped "83 B. M.

41" - S3. 60

2 mitta west by 2 milea south of poet office, 1 mile north of Harmony Bi'hiiolhousc, eaatof lY-ad at turn, 50 feet east of levee, in base of tlepl>(inc

pole; Pike with aluminum tagatamped "76B.M. 42" 75. M

Harmony schoolhouae, 12 miles northeast of Colum, in front of schoolyard

and afeotnorlhof gal*; iron post stamped -76 3 1909 B. P." 76, 153

Iliirmuny SL'boolhouac, 0.3 mile south of, at turn in road. 1,000 feet iriwt of house, in bam of telephone pole; spike with aluminum tag

tampwl -TS B. M. 43" r 4, H

Harmony schoolhouae, 1.3 miles soutli of, 6.3 mile weat of, entnnce to

M'luMiiti miiih. fiisl side of road, in base of 12 by spike'

wLlh aluminum tag stamped "TOB.M. 4" 70.39

Iliiniioiiy 2 miles south of, 2 miles north of Butte Creek schoolhouse, 20 feet north of entrants to ranch house, 2 feet north of telephone p..le; iron piwlstamiied "71 B lOOil B,Q,;" pole painted "U, S, B,M.". 70,820 Itiilte Creek whiK.lhiiu', I mile north of, 300 foet east of ranch house on we.sl sidf o( rcKid, in b!U*e of giktepost of section lino fence on east side of

piaii; siiike with iduminura tag stamped "70B. M. 45" 70.01

Bill 1 1' Irerk scIiiioIIkiuhi-, in southwest comer uf yard, in base of tree; spike

with iduniiiitim tii;; stanip<'d B. M. 46" 67, 98

Btuti- Creek schiiiilhmise, 1 mile fouth of. near gate on east side of road. ,")(K) fei't iif till) larm" feet north uf road crossing over Sac-

riiiiieiilii River U-vee; iron jx.sl Nlam|}ed "67 B 1909 B. R." e7.2D8

Itiille Cri'ik wliiirhoiise, 2 miles suuth of. 6 miles north of Colusa, 1,500 feel Miiilli of jni; in nmil cm eii.''l .side, ill base of 24-inch oak tree; spike

iiilii iiliLiniiiunil;igsliim[)i'd "fi2B.M.47" 62.32

Culiisii. 5 tiiiles north of. turn inroad liisoutli, QOO feet .south of Piunsworth riiueh, ill base of fence at corner; spike with aluminum tag stamped

til H,M.48" 64.61

Coliirsi, 4 iiiileH norlheact of, 0.6 niilo north of \\"ai'hinglon schoolhouse, 20 feet eiuit of oak tree 40 inches in diameter, near gate; iron post stamped '

"59 B 190U 11. S." .'iS. 910

Coliisii. !l,4 miles nnrlheost of, at Wnsliington schoolhouae, in base of tree

in road; spike with ahiminum lag stamped "62 B. M, 49" G1.69

Orldly wit and month to Unoak (portloa of Ua*). Gridley, 3,8 mile,' west of. north of road al point whore (elephonc line crosses to south of road, in base of telephone pule; spike with aluniimtm lag stamped "75 B.M. 18" 74.27

Primaby Leveling. 46

Gridley, 4.8 miles west of, north of road, at junction of north-flouth road, in'base of telephone pole; spike with aluminum tag stamped ''72 B. M. jjit. ISr*' 7i.32

Gridley, 5.7 miles west of, 0.5 mile north of Butte schoolhouse, at junction of road to south, north of road, 5 feet west of signpost; iron post stamped "71 B 1909 B. G." 7.0. 543

Butto schoolhouse, yard of, in base of gatepost; spike with aluminum tag stamped *'71 B. M. 20" 70.71

Butte K'hoolhouso, 0.5 mile south of, southwest corner of field at intersection of ea8t-w<\st road, in base of telephone pole; spike with aluminum tag stamixd ''67 B. M. 21" 66. 91

Butte schoolhouse, 1.5 miles south of, east of road at section line, in base of fence post; spike with aluminum tag stamped "71 B. M. 22 " 70. 73

Butte schoolhouse, 2.5 miles south of, 2.1 miles north of Pennington, west edge of road, at intersection of oast-west road, 500 feet of large barn; iron post stamped "71 B 1909 B. H." 71. 192

Pennington, 1.2 miles north of, west side of road, at fence line, in base of

fence post; spike with aluminum tag stamped "68 B. M. 23" 67. 71

Pennington, 0.2 mile west of, at intersection of east-west road, northwest comer of concrete culvert; bolt head with aluminum tag stamped "79 B . M. 24 " 79. 05

Pennington, northwest comer of schoolyard, at fence line; iron post stamped "82 B 1909 B.I." 83. 577

Pennington, 1.8 miles southeast of, south side of road, at junction of road to east, large gate to lane, in base of gatepost; spike with aluminum tag stamped "76 B. M. 26 " 75. 01

Pennington, 3 miles east of, 5 miles west of Live Oak, south side of road, at entrance of lane to house, in base of gatepost; spike with aluminum tag stamped "70 B. M. 27 " 69. 61

Point 8.6 mallet eait of meridian northwest and eait along highway to Pennington

(portion of line).

Noyesburg, 2.5 miles northeast of schoolhouse, 6.7 miles west of Pennington, 200 feet east of turn in road, 150 feet east of sheep dipping corral, in base of fence comer post ; spike with aluminum tag stamped " 62 B . M . 68 " . 62. 70

Pennington, 5.5 miles west of, opposite private road to north, south side of road at turn, in base of telephone pole ; spike with aluminum tag stamped "86 B. M. 69 " 86. 61

Pennington, 5.1 miles west of, at private road intersection to south, 20 feet north of gate at turn in road to northeast; iron post stamped "84 B 1909 B. Y. " 85. 110

Pennington, 4 miles west of, at turn in county road, small bridge over drainage ditch, at south side of road, in stringer; copper brad painted "64 B. M. 70" 64.56

Pennington, 3 miles west of, at turn in road to north, 2,000 feet south of large grove of oak trees, on northwest comer of road int-erection, in fence comer; iron post stamped "75 B 1909 B. Z. " 76. 467

Pennington, 1 .5 miles west of, at road comers north-south and east-west, in base of 36-inch oak tree; copper brad with aluminum tag stamped "80 B. M. 71 " 81. 06

Landlow lohooUiouse south to point 6.7 miles west of Oridley.

Biggs, 5.4 miles west of, at landlow schoolhouse, northeast comer of school yard; iron poet stamped "77 B 1909 B. A.-l " 77. 488

F

SPIRIT LEVKUKO III itAUrtlllSlA, IfiHW To 1010.

IaiuIIow inlMolhnuM. I.l oiilo* Muth nf, wM mda at nw). bare rail turns weal, in baep of lane* poat; * wilk umlnuui taMuupmi "73 B.M.B9"

IjtiiHliiH- trtmnitwiiw, 3.S mtla ol. WMt itda coBd-cbB m4. through RHltour Oulhria ranch, O.G ntUi mnk at Qutiuie bauae, in baas of tolnpbnnn pol; npiki' with aluuioiiiii UgsUmpiMl "fl8 I). M. 90" t

lAndlow erIuKilhiMiM, 8 ol, O.fi luileiuaUi of BftUour Gutiirur hcHUV; wuit bank nt Spring Vollvy Minitig i'a. rnaa), SO leet oorlh olrwul; iron piMit linpml "75 B I1K B, B.-l" :

Baldmr Gulhrio ntm-h, 1 lulu south uf, D 3 lila luuUi at Spring Vsllay MiaioK caiial. on urund-rliuB nnd, wet nide of rood, in basn of hnea poi: apik* wilh alumimun UgHamped "67 B. M. SI" (

Oridli-y, 7.7 of, at junclimi of srcotid-iB road thmugli Guthrie rich, in base of tvlophonv ; gpikn witb aliuninum stamped "47 B. M.9S" 67.

firittley, 6.0 miles west ot, north edge of rood, in baae ol telepboaa pole; flpikeand aluminum tA stamped "97 B. M. 03" KBf

Gridley, 6.7 milua west of. 0.5 mile north ot Biillo athwilbouae, at junrtioa of mu) li> mulh, north nd)<v of road, 5 feel of signpost; iron pwl

BArrOM. DmHAM, KELSOK, AXS HZWHAKD Tf QUASXAjIOIXB. Dnihui ewt (JiBC ta OroflUs-CblDg road.

iJurbam. at Houlhern Pui-llic Railroad (rowing; lop of nil lOi

.Purhuu, 0.8 tiiilc rant of, eoiitheast comer of bridge over Butte Creek, in

floor; coppar tutil vith aluminum Ugetuuped "167 B. M. 11" 16A.T7

Ptirhaiii, 1.8 milwt (met of. imrlh odRo of road. 300 foot east ol bridge over dniiii. 1 niUii I'liKi of Butte Creek, in baae of 20-iuch oak tree; spike with

iiluiiiiiiuiu It M.12" 155.29

hiirbiiii. J.llTiHli'siiiiHlof. south.'idoof bridge over dry creek, in floor; spike

|iuiiii.'.i -nu It. .\I. Kl" 161,37

Murliiirn, 1 Miil<-.- ly-t at juni 'iini of Durham-Oroville-Chifo roads, 10

iron post thumped-' 181 R 1909 B-3" 181.556

Point T,4 mllai weit of Blsfi nertli tilasc hithwui' to IIcImb (portion of Uaa).

ijiridlaw .-"luiilhouwi, L' miles west hv 6.8 milw north of, east side of north

alMlliu.'ul of coiiiri'lo rulvcrt ovor small .-reek; aluminum tablet

HlainjH'ii :i;l H VMKi H T.- 92.171

Uuidliiw 2 vf: of by 7.3 mllefl north, county wagon bridoovfr Ituilo north ei.d, iu floor; copper brad with aluminum

l.iitulliiw wli.iiilhouHi', 2 miles wiwt by 8.4 miles north of, 5.3 miles west <i( tsi'iFaiii, 1 luilou'iiKt of rouuly bridge on Oroville road over But le Creek, lit turn ill Onivillii roiid and power line; iron poat stamped "100 B 1909

B. Ii," 99.987

MiiUiii, -1.3 iiiiUw wrist of, county bridge over Butte I'reckon Orovilleroad, in Hi riiigorovor southwest pier; painted bolt with aluminum tag stamped

"Ml H. M. 7" 111.01

Ni'Imiii. :1 ii uiiliiH wiixt of, northeast corner of field, opposite Chinese touch liouii', in biiw (if foiico |)ost; spike with aluminum tag stamped " 105

11. Ms" 104.40

Ni'Ifuiti, 'J 1 iniliw Hi'Ht of, norlhwetil corner of field, private road much houMi, side of UroviUe road; iron post "108 B 190!) 11. K." 107.847

Primary Leveling. 47

Nelson, 1.1 miles west of, in front of ranch house on north side of road, in Feet.

base of telephone pole ; spike with aluminiun tag stamped " 112 B. M. 9 " . 111. 54 Nelson, 700 feet north of station, on east side of railroad, 5 feet north of

milepost 173; iron post stamped "120 B1902" 119.767

Chico west along highway to St. John.

Chico, State normal school, southwest corner of building, front face; aluminum tablet stamped ''201 B 1902" 200. 776

Chico, west end of town, south side of road, at intersection of river road and road to south, in base of telephone pole; spike with aluminum tag stamped "177 B. M. 20" 177.08

Chico, 0.7 mile west of, where road bends to south, 15 feet south of gate to Morehead ranch, in base of telephone pole; spike with aluminum tag stamped '174 B. M. 21" 174.31

Chico, 1.2 miles west of, south side of road, at intersection of road to south, in base of telephone pole; spike with aluminum tag stamped *'166 B . M . 22 " : 165. 78

Chico, 2 miles west of, south edge of road, 800 feet west of water tank, 60

feet east of oak tree; iron post stamped B 1909 B-5" 153.893

Chico, 2.8 miles west of, north edge of road, opposite river road schoolhouse, in base of 40-inch oak tree blazed on south side; copper nail with aluminum tag stamped '*143 B. M. 23" 142.67

Chico, 4 miles west of, 1.2 miles west of river road schoolhouse, south side of road, 100 feet west of cross fence line, in base of telephone pole; spike with aluminum tag stamped "131 B. M. 24 " 131. 04

Chico, 4.4 miles west of, 1.5 miles west of river road schoolhouse, where road bends northwest, north end of gate to second-class road through Phelan ranch, in base of telephone pole; spike with aluminum tag stamped "129 B. M. 25" 129.03

Chico Landing, 0.6 mile south of, northwest comer of bridge over slough,

in cap; spike with aluminum tag stamped "136 B. M. 26" 134.42

Chico Landing, east edge of road, 30 feet north of lane to house, opposite

boat landing, 3 feet from signpost; iron post stamped " 132 B 1909 B. 6 " . 132. 180

Chico Landing, 0.8 mile west of, north edge of Northern Electric Railroad right of way, 150 feet east of end of trestle, in base of 30-inch oak tree; spike with aluminum tag stamped "130 B. M. 27" 129.54

Seco station, Northern Electric Railroad, southwest comer of cattle guard; copper nail with aluminum tag stamped "140 B. M. 28 " 138. 71

St. John, Northern flectric Railroad station, at road crossing; top of rail. . 139. 5

St. John, 300 feet south of Stony Creek, 40 feet northeast of intersection of crossroads, in southwest corner of school yard; iron post stamped " 1 43 B " 142. 996

Point 4.4 miles west of Chloo south to Parrott school district (portion of line).

Chico, 4.4 miles west of, 1.5 miles west of river road schoolhouse where nxad tums northwest, in base of telephone pole at north end of gate to second-class road through Phelan ranch; spike with aluminum tag stamped "129 B. M. 25" 129.03

Chico Landing, 2 miles southwest of, east edge of road, east end of field gate, in base of 24-inch oak tree; spike with aluminum tag stamped "120B. M. 29" 119.76

Phelan hog ranch, 5 feet west of field gate, west edge of second-class road, 3.2 miles south of Chico Landing; iron post stamped " 123 B- 1909 B. 7 " . 123. 408

SriBIT I.KVELING IK CAU FORMA, IIHJ'; TU Il'lO,

Phlan hoig; rrnncli, 0 T uiU wm nf, Kiutfa nnd of uit bonk of creelc, nL liold iv. in base at Zl-lnoh ciak trv: spike with ftluinintUD tagitampHd fm. I20B. M,30" IIBM

humtt (1 0 mile nnttli "f, O.K mJlD anuth of Urge brick houev. t-iutt aiilp nnul. ut oimcir, la base ol 24-iiich o&k tree; spike with oliuniuum uqc iLamiiMl 117 B. M. 31" 117,51

Parmil -hi).>lhoii>, cmthwort cotaPt of Hrhonl ynftl, al inl*weclion of iron fi"rt sUwnpert "IWB ISOSJ B.8"

I'lUTutt urtionltiuuni-, 1.3 luiltMs suult) vt, '2JjO uailimuet of house, uo Purmtl nuirh, 15 of road, in base oC S-t-inch oak tree; spike with kluiuiiiuDi iMKlMnpiKl "lOti H. M. 7!" icifiS

sboolhuiuv. 2A miles soutii of, 200 would al huge gUe, west of mul, iu buD of oak Iree; spike with aluinitiuin tag numpod '-Hil U M. 72'" -, im.n

PajTvtt achoilbouse, 3.0 milea souUi of, at Parrotl triuigiilation gtaUon. 20 uuTth ol ruid, 100 feel ol lai new bam; xrati poat Btampml "109 B Iflffllll. 19" 108 HE

pMTOtt Lriant-ulatinn station, 1.6 milM eouih ol, sonlhweat oomcr of junf i>( white house, io bane of fnce puat; aplkw aluminiuu lai; sUunptd 102B. M. T3" - iCCM

Butto City, 3 mite wn by 6 tnilM nl, whore maJ turn eun, 15 fwi wlo( fencotiirner; Iron poat stamped "102 iS ISKM B. W ne,38f

Uultv Cily, 3 iniliw uaal by 4 miami uorth tif, opposite tDtetBoctiun of T road to weat, inbamottolophnnf> withaluminuiu lag stamped

PBCTftM tatoaHona* aottbeatt Oaytaa, tfatsM aartk OUoo.

llLty|..[], :i.l iiiiloH -r.l Mi, ivl ..f Ii.OKh, e..lh .-i.k' ..f roati, in

haw nf (i.|i.jilioiic. jxijc; spike aluminum tag stamped "110 B. M. 32" 108. H Inn, L'.H mill's wi>.-t <if, Hide of road, oppoeite large bam, 0.5 mile

ui'sl nf Hulti- Cily rriiiil, in basi' of :i6-inch oak tree; spike with aluminum

Dayton, '.'2 miU-s of, south siile of niad, northeast comer of field at

int<'m-i'I iiiii nf lluin- City-Diiyton mads; iron poet stamped "119 B

imw 119.032

Uujtiin, it. 7 mill' wiurhwist of, whc-re road jogs to eouth and west, eaat end

of gall' li> ruMc'h, in h;i?v of 40-inch oak tre<'; spike with aluminum taf;

Ptampfi! l.ill!. M. (i" 131. IS

llaylon, wcp;! end o[ town, 100 (net west of large gate to Line, south side o(

ni!ul. ill har'i- of Iclephoiie pole: spike with aluminum tag stamped

i;!: 11- M..V .- 136.78

I iiiili- I'li.-it of, [>iithi'U!<i t'ornor of field, at crossroads, in baae of

lolcphnrie ])nle; spike with aliiniinutu lag stamped "141 B. M. 4" 141. 12

'liii'u, 3.7 mili'8 southwest of, north edge of road, at bend in road, in base

of telephone pole 1699; spike with uhimiuum tag Btamiwd " 143 B. M. 3 " . 143. 30 Chic'o, 2.7 miles southwcDt of, east erlge of road, eouthnest corner of field.

alinlersoctionof road to Durham; iron post stamped "155 B 1909 B. 1". 154.986 t'hieo, 1.9 miles southwest of. north edge of road. 400 feel east of large bam,

in base of telephone pole; spike wilhaluminumt stamped "165 it. M. 2". 160.27 rhino, O.U mile southwest of, north side ol road, opposite T road eaat,

south of (jate to field, in biiiW of telephone pole; spike with aluminum

tag stamjiwl "174 B. M. 1 " 174. 221

Ohico, 0,5 mile south of, on east side of railroail, feet north o[ milepost

5; itwn peat atampod" 185 B 1902" 184.842

Primaby Leveling. 49

DaTton eaft to Dorluun.

Dayton, 1 mile east of, northwest comer of field at crossroads; iron post Feet stamped "142 B 1909 B. 2" 142.241

Durham, 3 miles west of, south side of T road to south, north end of gate,

in base of fence post; spike with aluminum tag stamped B. M. 7 ". . 149. 85

Durham, 2 miles west of, south side of road, at T road north, 50 feet west of cross fence, in base of fence post; spike with aluminum tag stamped "156 B. M. 8" 156.

Durham, 1:4 miles west of, east side of road, at intersection of north and south road, iu base of 36-inch oak tree; spike with aluminum tag stamped "157 B. M. 9' 158.02

Durham, 0.9 mile west of, at intersection of road, southwest comer of field, in base of telephone pole; spike with aluminum tag stamped "155 B.M. 10' 154.89

Durham, in front of station ; top of rail 159. 1

Durham, 0.4 mile south of, east of railroad, 270 feet north of 179, 5 feet from telephone pole; iron post stamped " 152 B 1902 " 152. 288

sterling Junction northwest to Chlco.

Sterling Junction, east edge of road, north edge of railroad right of way, at road crossing, in base of oak tree; spike with aluminum tag stamped "201 B.M. 15" 201.27

Barber, 1 mile east of, southeast comer of trestle over creek; painted bolthead with aluminum tag stamped "200 B. M. 14" 200.45

KEEFSBS AVD HORD QUADRANGLES. Chlco northwest along highway to Visa.

Chico, 1.7 miles north of normal school, northwest comer of bridge over Big Chico Creek; painted bolthead with aluminum tag stamped "194 B. M. 51 " 194. 34

Big (hico Creek, 0.7 mile northeast of, north edge of road, at turn north, in base of telephone pole; spike with aluminum tag stamped "205 B. M. 52 " 203. 74

CTiico, 3.3 miles northeast of, west edge of road, at lane to ranch, in base of fence post; spike with aluminum tag stamped "202 B. M. 53" 201.67

Chico, 3.8 miles northeast of, west edge of road, at intersection of road to west, in base of fence spike aluminum tag stamped "193 B . M . 54 " 193. 48

tliico, 4.6 miles northeast of, northwest comer of bridge over Mud Creek,

in rap; copper nail with aluminum tag stamped "194 B. M. 55" 194.04

Chico, 5.3 miles northeast of, east edge of road, at junction of road to east, where road jogs northwest, 50 feet south of gate to second-class road; iron stamped "249 B 1909 B. 14 " 248. 607

Chico, 6.5 miles northeast of, 350 feet south of road to east, at cross-fence line, on summit of ridge, in base of fence post; spike with aluminum tag stamped "293 B. M. 56" 292. 64

Chico, 7.2 miles northeast of, east of road, 20 feet south of intersection of road to Richardson's spring, in base of 20-inch live oak tree; spike with aluminum tag stamped "308 B. M. 57 "., 308. 14

Junction of Chico and Richardson's Spring roads, 1 mile west of, at east end of gate to second-class road, in base of fence post; spike with aluminum tag stamped "304 B. M. 58" 304.10

96094— BuU. 481—11 4

SPIRIT IJiVEUXO tit CALtFORNIA. IWlT TO IfllO.

ImrnoM ol ii4l Kiilunlina'a Spiin); mwlB, 2 milm wmi nt. nortti nditr nf md. oppniip raM Mid oj urrtianl at Rkto to nmd, in faaa <if M-incb otk ime; spin itb Aluminum tag sumpod ' 233 B. M. Fau.

232.8

, Chiro. S milm noMh u(, in sec. 28, T. 23 N.. R. 1 V., at T rasd aUuiK (uiith bank of ltr|[ fmok. BuudiMM earner of pacb ofrhanii iiua part itampoil "227 ft IB09 H 15" 221 2

ShanuiMi tanrb. itiiiiaiiui hoiiw. north mul, tn base of 24-lur:fa lomwt

tirm; Kfiikp with aluminum taic stamped - 1J8 B M. 00" lOT, U

Shuiuonmw'h. l.'imilrarwnrt of, AOfiw't north of inlcmx-tlunur Chico-Vina- Cuhaax-t nails, 0.5 mile sDUlb of Kurk <'roDk ftriilgti. in bant of power pnle; yjlh aliHwinuni tag rtampri "1T7B. M. fil" ir7.3S

tiici4>; iroppcrtuulfrith aluminum tagstampHl "ISS B. M. W" IS3.BB

Rwk iVfk [faiilrn. I nonhraiA of. -i.h miin euutli of Antulope K-honlhoum, WBBt of nwl, at road thiough tanc-b "IMIB IMS B. IB" IBSaH

Anlelopa nrbnaUioiHe, l.S huIm aniiUi of, wnxi ihIsr o( at croM-fanrn line, lu baM uf loni-A puM ; ste with aluminum tag slompMl "210 B. M 83" 2i8,

Aniolope irhuQllKiuMi, M tent aoulh uf southtrMt comer of school yard, in bAmnf apikawilhldiiminum B. M. M"... -JNITO

AntnlnpowhnnlhouM, i milo north of , iriwt odge of road. Kiulhoast comer of ou i-tHinly lino, in basv of pcwi.; ejuko vitli aluminum Isk M, 8A" 3SS. !S

Iiin CriM-'k, KKilhwoBl I'unicr of bridge.-. in tpi coppar nail with aluminum

Live Oak acfaoolhouw. D.S mile north by O.fl mi1 west ol. 2.6 milea met of InaiiiriiliiTinn 'aii'iNiii Siiiufi.inlph"-'|ir,iri''h south edv'i' of wlivrc niH.I Tiir!i,' vn:. in h.iwIil.T buried Rush wilh ground; alum- It I'KKt U. IT" 283.068

Siiiiifnnl ?Il.i>|) r.iricli l.tiiiiili's east of, south edge of road, ;it fi'iii (iiniiT, ill lia.-'of fi-ncppoel; spike with aluminum lag stamped

ltuuford .-ihn-p niiiiK 1 niili' cast of, uorth edge of road, in

hiunKif [i-uri. ]Kisi; t-|iik.> witli aliiniiiium tag Mamtxd '229 B, M. 68".. 228.65

Slaiifonl shiH'i> rmiili luii.lniiiirii-rs, i'lO fwtsouthffost of house, 5 feet north .>f triaiii;uUiiioii fiuiimi; imii |Hist stamjuKi "238 H 1909 B 18" 238.035

Sliiiiford slii'i'p ruiiih hiMdiiuarli'n;, O.S mile north of, west edge of irrigation diK'li. iu Kl-jiu'h willow I ri'i': s>>ikt! with aluminum ta); stamped

Stiiuford sh(>(')> ranch hcadquarliT;!, 1.4 miles north of, 4.4 miles east of Vina, at iiitcr.-itiiiti of nast-wiwl nwd, north end of gate, in gate poet; !-pik<; with aliiniinum tagstnmiK"! "280 It. M.(i9" 279.98

Siiiiiford f'hei'p rant'h headnuarter,2.ti miles uorthof. 3,4 miles ea, of Vina, house, north side of road, al intersection of uorlh-south road, in base of fciieo spike with aluminum tag stamped "262 B, M. 70". . 262,00

Vina, 0,4 mile south o(, on cast side of railroad. 30 foci north of milepoat 204 ; iron jiost stamped "202 II 1902" 202.20

OrovUI* Borthmat i.1dii( hicliwar wl slactrlc rMlto&d to Starlloc JnaetloB. Oroville, Southern Pacific Railroad station, 200 feet south of. aouth Bide of road, east side of track, 6 feet eact of railroad property line post; iron post stamped "205 B 1909 J." 204.8

Pbimaby Leveling. 51

Oroville, northwest comer of steel bridge over Feather River, in concrete abutment, at end of railing top of bolt head; stamped B, painted ''191 B. Feet. M. 44" 192.41

Oroville, 0.6 mile north of, at crossroads, in base of signpost ''Chico-Cherokee;" spike with aluminum tag stamped B. M. 45" 268.04

Oroville, 1.5 miles north of, 15 feet east of fence line, where power line crosses road, in base of power pole 445; spike with aluminum tag "266 B. M. 46" 267.54

Oroville, 2.6 miles northwest of, northwest comer of field, 250 feet south of

large barn, at foot of small ridge; iron post stamped **300B 1909 B 12 " . . . 301. 735

Oroville, 3.9 miles northwest of, east edge of road, at T road to west, in base of power pole 372; spike with aluminum tag stamped "291 B. M. 47 " . . 291. 93

Oroville, 4.8 miles northwest of, east edge of road, in base of power pole pole 21/29; spike with aluminum tag stamped "311 B. M. 48" 312.45

Oroville, 5.8 miles northwest of, at Wick's ranch, at junction of road to northeast, 100 feet east of blacksmith shop; iron post stamped "265 B 1909 B 13" 265.053

Oroville, 6.8 miles northwest of, 1 mile northwest of Wicks, south side of road at intersection of second-class road, in base of fence post; spike with aluminum lag stamped " 264 B. M. 49" 264.15

Dry Creek, 1 .2 miles southeast of, south side of road, at junction of road to south, in base of fence post; spike with aluminum tag stamped "251 B. M. 50" 251.46

Rio Seco schoolhouse, north of, northwest comer of field, 500 feet east of Dry Creek, at intersection of Marysville-Oroville roads; iron post stamped " 190 B 1909 B-10 " 189.744

Dry Creek, 1.4 miles northwest of, south side of road, at second-class road, in base of power pole 13/19; spike with aluminum tag stamped "223 B. M. 38" 222. 68

Butte Creek, 5.7 miles southeast of, east edge of road, in base of power pole

13/6; spike with aluminum tag stamped "184 B. M. 37" 183.60

Butte Creek, 4.6 miles southeast of, east of road, 100 feet south of bridge over drain, in base of power pole 12/3; spike with aluminum tag stamped "166 B . M . 36 " 165. 80

Durham, 4 miles east of, at intersection of Diurham-Chico-Oroville roads, 10

feet west of signpost; iron post stamped "181 B 1909 B-3" 181. 556

Butte Creek, 3 miles south east of, east edge of road, opposite transforming station on powor line, in base of power pole 1 ; spike with aluminum tag stamped '172B. M. 35" 171.71

Butte Creek, 1 .6 miles southeast of, north edge of road, at junction of Chico- Oroville-Paradi.'e roads, in base of power pole 1/4; spike with aluminum

tag stamped "172B. M. 34" 172.01

Butte Creek, 1.2 miles southeast of, south edge of road, in base of power pole

1/10; spike with aluminum lag stamped "177 B. M. 19" 177.38

Butte Creek, 0.8 mile southeast of, north edge of road, 600 feet east of water trough, in base of 36-inch oak tree; spike with aluminum tag stamped "185 B. M. 18" 184.58

Butte Creek, 30 feet west of approach to bridge, north side of road, in base of power pole 2/18; spike with aluminum tag stamped "191 B. M. 17 ".. 191. 44

Carmine, 200 feet north of Northern Electric Railroad station, west edge of county road, 50 feet north of large gate, at junction of Chico-Oroville road; iron post stamped "191 B 1909 B 4 " 191. 217

Sterling Junction, 0.8 mile south of, seventh telephone pole south of milepost 3, east side of right of way, in base of telephone pole; spike with aluminum tag stamped "203 B. M. 16".. 202. 87

52 Spirit Leveling In Caljfobnia, 1907 To 1910.

Oroville weit alone hlfhway to Trei Vlai, thaaoe north to Bio Seo

Oroville, northeast comer of courthouse, 4.5 feet from ground, in concrete Feet. wall; aluminum tablet stamped 'HS B 1909 B I"..: 172.736

Oroville, 2.5 miles west of, at road crossing, reverse curve in Northern Electric Railroad track, in base of telegraph pole; spike with aluminum tag stamped "178 3. M. 16" 177.99

Oroville, 3.5 miles west of, at road crossing, northeast comer of right-of-way fence; iron post stamped 203 B 1909 B H".: 203.425

Oroville, 5 miles west of, 1 mile east of Tres Vias, at trestle on Northern Electric Railroad and long fill in embankment, in base of power pole; spike with aluminum tag stamped " 169 B. M. 15" 169. 39

Oroville, 6 miles west of, 200 feet southwest of Northern Electric Railroad station at Tres Vias, northwest comer of Floral schoolhouse yard; iron po8tBtamped**160B. M. 1909B. G." 160.307

Oroville, 7 miles west of, 1 mile west of Northern Electric Railroad station at Tres Vias, north side of road, private roadway to south in base of power pole 1/0; spike with aluminum tag stamped 128 B. M. 14 " 128. 17

Shippee road, 1.2 miles south of Northern Electric Railroad station, southwest comer of barnyard, in base of power pole; spike with aluminum tag stamped 122 B. M. 43," at intersection of road to east 122.48

Shippee road, Northern Electric Railroad station, north edge of right of way, in base of power pole 19/10; spike with aluminum tag stamped B. M. 42" 125. 20

Rio Seco schoolhouse, 0.6 mile west of, 2 miles south of, west of road at T road east, opposite power pole 18/14; iron post stamped '*136 B 1909 B 11 " : 136. 474

Rio Seco schoolhouse, 0.6 mile west by 1 mile south of, east edge of roads, in base of power pole 17/10; spike with aluminum tagstamped** 153 B.M. 41 ". 153.29

Rio Seco schoolhou, 0.6 mile wst of, northwest confer of bridge over creek, " in cap; copper nail with aluminum tag stamped 162 B. M. 40 " 162. 28

Rio Seco schoolhouse, east end of gate to school yard, in base of gate post; spike with aluminum tag stamped "182 B. M. 39" 182.43

Rio Seco schoolhouse, 1.4 miles north of, northwest corner of field, 500 feet from Dry Creek, at intersection of Marysville and Oroville roads; iron post stamped B 1909 B-10" 189. 744

Bioos, Oridlet, Hohcut. And Palebmo Quadrangles.

Point 7.1 miles nortliait of Maryivllle northeast 10 miles, thenoe west to Honent

(portion of Une).

Nigger Jack Slough, 3.8 miles north of, southeast comer of second-class road to east, in base of fence post; spike with aluminum tag stamped " 1 02 B . M . 66 " 101 . 60

Nigger Jack Slough, 4.9 miles north of east edge of road, at section line, in base of fence post; spike with aluminum tag stamped "106 B. M. 67 ". 107. 26

Honcut, 3 miles northeast of, at junction of roads, opposite schoolhouse, at small gate to school yard, in base of 20-inch oak tree; spike with aluminum tag stamped "137 B. M. 75" 137.03

Honcut, l!3 miles east of, at intersection of north-south road, west end of old store, at fence line; iron post stamped "116 B 1909 B X" 115.714

Honcut, 0.8 mile east of, northwest comer of bridge over Honcut Creek, in top of cord ; spike with aluminum tag stamped ' ' 114 B. M. 76 " 113. 13

Primary Leveling. 53

Point 8.6 miles north of Wooddxift whoolhonae north and east alone road to

Palermo.

Wooddrift schoolhouse, 3.2 miles north of, 30 feet south of road running east, 300 feet south of blacksmith shop, east side of road; iron post Feet, stamped ''78 B 1909 B.B." 77.261

Honcut, at large gate in northwest comer of school yard, in base of gate

poet; spike with aluminum tag stamped "80 B. M. 6" 79. 91

Honcut, 1 mile north of, opposite Yuba dairy ranch, center of road, in base of 30-inch oak tree; spike with aluminum tag stamped B. M. 7".. 82. 34

Honcut, 2.2 miles north of, west side of road, 350 feet south of bam, in base of 36-inch oak tree; spike with aluminum tag stamped "85 B. M. 8".. 84. 64

Honcut Creek, north bridge over, northeast comer of; painted bolt head with aluminum tag stamped "80 B. M. 9" 79. 36

Honcut Creek, 0.8 mile north of, east side of road, at junction with road mnning east; iron post stamped "87 B 1909 B.C." 86.338

Honcut Creek, 1.5 miles north of, 150 feet south of road running west, west edge of road, in base of 30-inch oak tree; spike with aluminum tag stamped"92B. M. 10" 91.90

Central schoolhouse, 300 feet south of, 150 feet south of road leading east, east side of road, in base of 40-inch oak tree; spike with aluminum tag stamped "97 B.M. 11" 96.31

Central schoolhouse, 1.1 miles north of, 4.9 miles east of Gridley, northeast comer of field; iron post stamped "101 B. 1909 B. D." 100. 383

Union schoolhouse, 2 miles north of, west side of road, opposite bend, in base of telephone pole; spike with aluminum tag stamped ' ' 102 B. M. 47 " . 101. 90

Union schoolhouse, 3 miles north of, west side of road, at bend of road, 1,000 feet north of lane to house, in base of telephone pole; spike with aluminum tag stamped " 103 B . M . 48 " 103. 06

Union schoolhouse, 4.1 miles north of, 4.8 miles southwest of Palermo, west edge of road, at section line, southeast comer of small alfalfa field, 500 feet south of house; iron post stamped "119 6 1909 B. O.*' 118. 895

Union schoolhouse, 4.6 miles north of, 4.3 miles southwest of Palermo, west side of road, at intersection of road to east, in base of telephone pole; spike with aluminum tag stamped "111 B. M. 49 " 110. 65

Palermo, 3.1 miles west by 0.6 mile south of, center of road, 0.2 mile north of small house, in base of 30-inch oak tree; spike with aluminum tag stamped "127 B.M. 50" 126.31

Palermo, 2.6 miles west of, at intersection of east-and-west road, southwest comer of road, 600 feet west of house; iron post stamped "139 B 1909 B. P." 138.735

Palermo, 1.6 miles west of, 25 feet west of intersection of north-south in base of telephone pole; spike with aluminum tag stamped B. M. 51 " 137. 90

Palermo, 1.1 miles west of, southwest corner of bridge over small creek, in

top of cord; bolt head with aluminum tag stamped "154 B. M. 52" 153. 29

Honcut Creek eait to Honcut, thence north to Oroville.

Honcut Creek, 0.8 mile north of, east side of road, at intersection of road to east; iron post stamped "87 B 1909 B. C." 86.338

Honcut, 2.8 miles west of, northwest comer of bridge over creek, in top of cord; bolt head with aluminum tag stamped "81 B. M. 61 " 80. 52

Honcut, 2 miles west of, east edge of Westem Pacific Railway right of way, at road crossing, in base of telephone pole; spike with aluminum tag Btamped"83B.M.60" 82, 2&

8PIBIT LF.VELISO IN CAUFilBNlA, IWH 1910.

Ronciit. 1.3 milo wast iif, lough itdn ol rond, in bam n[ po(; rpikf 7m,

with ftluiuiniiin tag nUmjied '88 B M. GO" Sj U

Ilaarul, nurthwoil iiinier of school buiUlinif; iron poet tuned "lOG U

IWWB. S." lOa,

tlaneul, north wigt- ot (own, aist lgt' of mliiiiul right ill tray, in base of

mtlcpoiit l:<7i Kpika with aJiuninum Ueatainpt;d "9U U. M." U-tf

Uoni-ut, 2 tnilm north ut, Mat edKe of Tkilroad i%hl way, in base ol mile-

poKi 13ft; Dpiko with ainniinum lofi stamped "100 B. M. 57" lom

Honcut, 3 milw ul, aal iidgn of rif ht uf way, in base of nulopiMt 139;

piku with oluuiiuuiu toKtiunprd "112 11. U.56" IILK

Palermo, 4 milan xoutfa of, ai Coxe Lane, 250 (pet north of niUepoBt 140, east

"iKcofriiil at way; iron post stamped '121 B IflOO B.R. " laftTft

Pftlemio, 3 milan wiiith of. wuthcest timer of trmitle, at nulepoet 141; boll

hwul with taumjnuia Ug iiUmpnd "122 B. M. 56 " I2i. n

Paloniui. 2 mile south of, in base trf nilepost 143; ipiks with aluminum

lai; Hianiped "131 B. M. 64" 131 W

Ilcant, in front of Wettem Pacific Hailway etatiun; lop of caat rail. i

Palurmo, t iuil< south of, Houtheast corner of trestle over creeic, oppuute

milcpool 143; bull with aluminum tag stamped "149 B. M. 53". 1411.01'

Palprmo, in front of Soiilbem Pacific Kailrokd slalioii; lop of tail I5j. B

Palarmi), Bouthwest comer of brick schoolhoufw, feet above g;muad:

aluminum tablet stamped "170 B IflOB B. y." iSftUT

()rovill, Southern Pacific Railroad alaliun, 4.8 miles south of, 0.5 mile

north of Palermo tjtation, 20 feet auuth of aiboord 143.C, south of rimd

rrosaing and east nde of track, in base of telegraph pole; spike with

aluminum UBtaiupBd "IBl B. U. 21" lUV

Oroville, 3.7 miles south of. along railroad track, at first road crossing south

of ilia Vcnma, in corner ui rit;h(-<if-wa} fenc.'; iron p-M stamped "20.

II IS. K." 205. al

Oroville. 'iJi inileK south of, on west aide of railroad track, in base of tele-

(graph jjole: aluminum lag elaniped "221 B. M. 20" 22181

Oro\-illo, Koulhem Pacifii' Kailroad elation, 1.5 miles south of, east aide of

right of n-ay, in baweof lelegrjjili pole; spike -ith alimiinum tag stamped

"laS B. M. 19" 197.78

Oroville, Souliieni Pacific Itailroad station, 1 mile south of, east aide of

imck, in baeo of iiguboard "Station 1 mile;" spike with aluminum tag stumiHil "17S B. M. IN" 177.87

OridltF. tut ( mllag. thence Bortli br road and altctilc nllroad to Tim Vlu.

Uridley, in front of atalion; top of rail 92. 9

Gridh'y, 50 feet eaut of railroad track, south of road, 500 feet south of station, in base of telephone pole 15; spike with aluminum lag stamped "90 1!. M. 15 89. 93

Gridloy, 0.7 mile east of, south of road, opposite brown house; in base of 40-inch oak tree; spike with aluminum tatrntaniped "94 B, M. 14" 93. 73

Gridlcy, Northern Electric Railroad crossing at atjilion; lop of east rail 97. 6

Gridlev, 1.8 miles east of, center of north-south road, 1,500 feet east of Northern Electric Railroad, iu base of 40-inch oak tree; spike with aluminum lag stamped "94 B. M. 13" 93.04

Oridley, 1 .8 miles eaat of by 1.2 miles north of, 500 feet cast of OroRancho elation on Northern Electric Railroad, in base of 60-inch oak tree; spike B-ith aluminum lag stamped "98 B. M. 77" 97.7*

Oro Rancho, 0,4 mile northeast of, 30 feet north of Butte County canal, at Allen ranch, in base of telejAone pole; spike with aluminum tag stamped 101 B. M. 78 " . . 100. 73

Pbimary Leveling. 55

Feet.

Butte County Canal, surface of water; May 5, 1909 95. 5

Oro Rancho, 1.4 miles northeast of, west side of road opposite Reed ranch house, in base of gatepost; spike with aluminum tag stamped *'99 B . M . 79 " 98. 943

Biggs, 3 miles east of, 0.3 mile east of Northern Electric Railroad, at intersection of road west, northeast corner of orchard; iron post stamped "109 B 1909 B. Y." 108. 884

Hume (Northern Electric Railroad station), road -crossing sign north of road and east side of track, in base of signpost; spike with aluminum tag stamped *'110 B. M. 26" 109. 76

Tres Vias, 5 miles south of, 1 mile north of Hume, at road crossing, in base of north pole, of overhead crossing poles; spike with aluminum tag stamped 114 B. M. 25 " 113. 96

Tree Vias, 3.9 miles south of, at road crossing, in deep cut, in embankment, on north side of road, in base of post of cattle guard ; spike with aluminum tag stamped ''129 B. M. 24'' 129.48

Tres Viae, 3 miles south of, at road crossing; iron post stamped "121 B 1909

B. L." 121.004

Tres Vias, 2 miles south of, at road crossing, east side of track, in base of right of way post ; spike with aluminum tag stamped "135 B. M. 23 " 134. 86

Tres Vias, 1.1 miles south of, at road crossing, in base of north pwle of overhead crossing poles; spike aluminum tag stamped " 153 B. M . 22 . . 152. 96

Tres Vias, 200 feet south of Northern Electric Railroad station, 6 miles west of Oroville Floral schoolhouse, northwest comer of school yard; iron post stamped " 160 B 1909 B. G. " 160. 307

Bluffs east 8 miles.

Biggs, 1.3 miles north of, west edge of railroad right of way, where wagon

road turns west, in base of telephone pole; spike with aluminum tag

stamped "91B. M. 83" 90.32

Biggs, in front of station; top of rail 93. 8

Biggs, 1 .3 miles east of, southeast comer of intersection of north-south road,

in base of telephone pole; spike with aluminum tag stamped "96 B. M.

82" 95. 898

Biggs, 2.1 miles east of, southeast comer of bridge over Butte County canal,

in bulkhead; spike with aluminum tag stamped "106 B. M. 81" 105.86

Biggs Junction, Northern Electric Railroad station, east line of right of way,

in base of telephone pole; spike with aluminum tag stamped "107 B. M.

80 " 106. 39

Point 3.9 miles east of Gridley west to Feather River.

Gridley, 3.9 miles east of, northwest comer of steel bridge over slough, in

cord ; spike with aluminum tag stamped "100 B. M. 12 " 98. 35

Gridley, 2.7 miles east of, southwest comer of bridge over Feather River, in

concrete abutment; aluminum tablet stamped " 102 B 1909 B. E." 100. 424

Gridley, 2.7 miles east of, on southwest pier of Feather River Bridge; 25- foot mark on water gauge 99. 381

Gridley, 2.7 miles east of, surface of water in Feather River, April 22, 1909. . 85. 6

Point 1 mile north of Silsby east and north via highway to point 8 miles west of Tres

Vias.

Sikby, in front of station signpost; top of rail 108. 3

Silsby, 1,000 feet south of station signpost, at road crossing, 150 feet east of track, on north side of road,in base of right-of-way fence post; spike, with aluminum tag stamped "102 B. M. 10" 101. 8S

Ukr

KbriwriMMtwa-r-HB H IS' lo&a

"Iis B 1Sd9

Owiiilh. t Bh wmt St wWTMi-tiw of toOatj Mtd liaw, to ke of Hft; qOc tih afagBdnmB MunpHl " 1*1 B U

131 Si

liiiMJ, SmOmwtattd, nartk mde ut toad, nd. ia hve rf ; tfikm with i BUS' --

UvMkL. 3 J mlM <rf, 4 flrilw notfa M Vaim KboollMH*, Ldc fil mid. at ncBET. in baie ri bace pal; tpikr with iBnunani ta

tfoan rtit Btt , X3 wilm nvik oC. 1 vile art (4. math of Rad, It fct MM bndgo anr dam. in b*wllmriMal; ke villi aJ ami -

raoMt Khwlhoww. Z nnk* noftli br 1 utile wt of. tuvtli edgv <rf roul, ai MiMi BiM. sen fiwl ni of Mittii house: imo pari tFUmped -65 B 1909

Gffdley. 1 Bole weal ol. mmUi mie tt iwd. at caner wemd lewling .

in haw r-rf i.-iwrr '"'h aluminum lai; -lamp.-) '-iT R. M \li" . M.*S

GridUy. 1.5 mili' hcc uih ircul. junclioD of road south, in base

!iridlr'*-. 2.'" mill- o'-i i.j', (h,! a>'7-t of plac'e where lelephoDe line t.. north id.. nf nu.l. m.rih mIl-c of hkkI. at action line; iron post I'tamp.'.i "sl I! 1!.09 11, y." 81.048

4 milif ivc-t ni. S 7 iiiili-?; riulhfaji nf IViininRtoii, <>oulh side of mail. opjHi-itf- iiiull liiiu.-. l-j fn'I pofx of (rJlo; iron post stamped "72 B irtOS B. J . 71. 769

.ivHak. 33 mill- vv.-t i.f. on niihwf comer of concrete culvert over

.ivcirdk, J.;i mill's -i--i of, noMh of road, al inlervertion of north-eouth mad. in ba-i- of fi-nci. -ilh aluminum lae stamped "71 H.M.2!|- 71.28

iviTFak, 1 A milcM west of, ninth ido of road al interseclioii of iiorlh-south rmid. in of iclcphonc spike uiih aluminum tag stamped "7:Ut. M. :iO" 73.09

.ivwrnk, (ipixKitc north eml of larirc -an'hotise. west e-ljie of railmad right of way, iS feel south of rjilroaci crissiiit:. in Iml-c of telephone pole; spike' with aluminum tuK stamped "7-1" 74. 25

Etna Kills. Hoopa, Preston. Sawyer Bar. Seiad, and Yreka quadranglea. KISKIini.' rOlSTIKS.

The elevations in the following list arp basil upon bench marks at Montimup, Ilombrook, and Hoopa. and upon mean sea level datum in agreement with elevations given in Bulletin 342, in which .bulletin

Primary I.Eveltng. ' 57

are published additional elevations in Yreka quadrangle and vicinity. The prism level and yard rods were used on this work, and certain large errors in the field computations account for the discrepancies between stamped and published elevations.

The leveling was done by L. F. Biggs in 1907, except for a portion of the work in the Hoopa quadrangle done by him in 1906. The descriptions of the bench marks established in 1906 are here republished from Bulletin 342 in order to complete the list. The work was not in cooperation vith the State.

YREKA QUADRANGLE. Montague west rJong road via Yreka and Forest House to Fort Jones.

Montague, 1 mile south of, east of railroad, second telegraph pole north of Feet, milepoet 376; iron post stamped *'2518 B 1902" 2, 518. 845

Montague, 1.5 feet west of northeast comer of Montague Hotel; aluminum

tablet stamped ' B-B-1907-2538 " 2, 537. 665

Montague, 1.7 miles west of, at northwest comer of Shasta River Bridge, 2 feet above abutment, 1 foot below aluminum tag; bolt head with aluminum tag stamped ' ' B-2-2455 " 2, 455. 07

Yreka, high school, in stone foundation of left pillar of east approach; aluminum tablet stamped "B-B-1 907-2-261 6" 2, 615. 926

Yreka, courthouse and jail, in cement foundation of northeast comer of jail; aluminum tablet stamped ''B-B-1907-3-2625" 2, 624. 886

Yreka, 4.6 miles southwest of, 0.2 mile east of Forest House, 10 feet north of road, in cut slate ledge; aluminum tablet stamped ' B-B-1907-4-3056 ' - 3, 056. 010

Summit of divide between Yreka and Fort Jones, 400 feet east of, north edge of road, in slate bowlder 3 by 3 by 3 feet; aluminum tablet stamped **B-B-1907-5-4117" 4.117.440

Summit of divide between Yreka and Fort Jones, 20 feet south of road, in base of pine tree 36 inches in diameter; spike with aluminum tag stamped 'B-13-4159 " 4, 159. 41

Fort Jones, 8 miles northeast of, 6 feet west of road, 6 feet north of creek, in base of alder tree 14 inches in diameter, spike; aluminum tag stamped '' B-1-3411 " 3, 411. 55

Fort Jones, 6.8 miles northeast of, 6 feet east of road, in base of pine tree 42 inches in diameter; spike with aluminum tag stamped "B-16-3178" 3. 178. 83

Fort Jones, 5.5 miles northeast of, 6 feet north of road, at rocky point, in slate ledge; aluminum tablet stamped " B-B-1 907-6-2935 " 2, 936. 120

Fort Jones, 4.4 miles northeast of, 250 feet north of schoolhouse, 15 feet north of road, in of oak tree 36 inches in diameter; spike with aluminum tag stamped ''B-17-2916" 2, 916. 82

Fort Jones, 3.2 miles northeast of, 6 feet south of road, in bowlder; aluminum tablet stamped " B-B-1 907-2829 " 2. 829. 300

Fort Jones, 1 mile northeast of, 40 feet east of forks of road leading north, in base of pine tree 36 inches in diameter; spike with aluminum tag stamped ' ' B-20-2771 " 2, 771. 00

Fort Jones, in northwest comer of Berm's brick building used as livery stable; aluminum tablet stamped ' B-1907-8-2747 " . . . : 2, 747. 365

Yreka west and south via Monnt Vernon mine house to Fort Jones.

Yreka, 4.3 miles west of, south of road, 25 feet north of ditch at point of rockff, in large bowlder; aluminum tablet stamped '*B-B-1907-72-3107". 3, 107. 296

F

Bl'IBIT LF.VF-UNO IN CAtJPdBNlA. IftffI TO Iftlfl.

Yiek, 7 A wmI nottfa of Minuuiit. 500 ftt wad nf Mnunt Vcmoo mine house, in Dluminiim lahlil Umped "B-B-IIUT-T rut.

YkIu. 10.1 wait of. uurth ul pihI. 500 (m-i o[ D8ilva , in bow III iiinc Uw 24 in divavtnr; luU with ftlotBUtum tay xlainiMd K-223-M:6" ... S,<TS.10

Yn-kn, 11,9 mili nf, nartli nf mad lli U Gulcfa., in \argB hnwUior; kluDiJuiiiii UblelAUmpMl 74-B-B- IS" 3,2I&.DI

K'lrt Jouiv. 4.5 nurtliiaul uf. ocrUl iif raiid, 260 leet west nlil bIibcIc, in bAM?of piiiP tivp llinchn in diameter; nail fttiiintnuin Ug stamped -B-22+'3017" 3.01.l ]

Fort Jcinra. 4 milee nurtiiraet of, 300 feet west of Dta'e rich house, north ruad. at foot, of pine tree, in rock led§;e: alumiQum Ubiet stamped

B-IJ-1907-75-29a2" S,94.

Port JoBM t bUu (put of Um to Ztu Uat}.

F*ort JoHM, 1 inilo iif. 20 frt fast of Unr', in bam of {liue Uv 48 incbwui diameU'r;>-pike wllli alumbum bm -luiiiiml "it-::l~273ti" 2,73S.A

Fort Jouvs, 3 mili-s (outhtrcvl of, 60 fi-"1 nkt of rnui, in base of pine ti inc-hmin wiihaluminum UiPUmped "&-23-2746" 2,744.M ]

Fort JuuQH, 4 luileH wmlhwtal of, 20 twl (wl of mud. iu lium- of oftk tree 36 Inrhniin diameter; spike with aliuninuin lag -B-24-27SS" 2, 75a 87

Fort JoUM, ii.6 milverauthwwtof, 7,H milea north of Etna, mirth wwl comer nf erhooUiouee, in earner atoue; aluminum tAblet stamped "G-10D7-&~ 2768" Z,75t8O0

Etna Milla, 6 utiles uorIlieat of, 30 feet weiC of road, in bue of pine tree 24 iiirb'win diameter; Kpike with aluiniDum lag stamped "8-26-3808" 8,801.20

Fort Jones', 1.1 niilrfi MHitli of, bridtro over Scott River, above aouthwMt

KUhaluoLinum tii;.- .camped "B-188-2722" 2,722.10

Firl Jorii's, 1,7 miles MHith of. ;iO f.'l north of big mte in rail fence, eaat of rout. in lia.-'e of pine Irce 'Mi ini'hex in diameter; nail with aluminum tag Plampc*! 'l(-lP-27:t) 2,735.73

Fort Jones, 4.7 niilc's wnich of. I2.t feet cast of Kitten Creek echoolhouae, eanlof niLid. in biiscof ouk tree 30 inches in diameter; nail with aluminum tjiR stamped 'It l!H-27G8" 2,768.06

Greenview, in center nf front wall of Denny Itiirl'o.'rintoro; aluminium tablet stamped B--l!<07-fi4-2l2" 2,812.000

Greenview. 1.2 mile- .tenth of, west of road, 25 feet west of comer of rail fence, in base of pine tree 24 inches in diaincler; nail -ilh aliuninum lag

Btampiii 'MKI!)-.'-2Saf 2,803.28

HuBbnrc (oBthaMt tlotif read to point t mllai lODth of Seott Bar.

Hamburg, 1,(1 mili-s southetu'l of, in nnrlheasl corner of hridfie over Scott

River; key boll slamM -U-ISK-;." ahiminnm tat'stamped '8-1582-167" 1, 682.91

Seolt Bar. northeaal corner of Simon's warehou.-e; aluminum tablet stamped 'B-R-lflOT-SS-lUS,-) " 1, 687. 135

Scot! Bar, 5..1 miles south of, west of road, in large bowlder; aluminum

tablet stamped " B-B- 1 707,-59-215;) " 2, 154. 988

Point It.H BUloi BortbwHt of Fort Josu lontliMUt 1.1 mllii.

Fort Jones, 10.3 miles iiorlhwesl of, north of rosd. on large bowlder; chisel point painted " U. S.-179-2737 " 2, 736, 22

Primaby Leveling. 59

Fort Jones, 8.2 mileb northwest of, north of road, 1,000 feet east of Pinkerton's ranch, in rock ledge; aluminum tablet stamped Feet. 2655 " 2, 653. 896

Fort Joneg northwest to Meamber School.

Fort Jones, 3.4 miles west of, north of road, opposite house, in base of oak tree 36 inches in diameter; nail with aluminum tag stamped "B-185- 2721 " 2720. 53

Fort Jones, 6.4 miles west of, north of road, at bend, 1,000 feet north of house, in base of pine tree 60 inches in diameter; nail with aluminum tag stamped "B-183-2726" 2725.60

Mouth of Scott River east to Hombrook.

Mouth of Scott River, 2.3 miles east of, west of road, in base of oak tree 24 inches in diameter; nail with aluminum tag stamped "B-197-1581 " 1, 582. 94

Mouth of Scott River, 3.9 miles east of, north of road, 0.5 mile west of Everill ranch house, in slate ledge; aluminum tablet stamped " B-B-1907-65- 1593 " 1, 595. 041

Mouth of Scott River, 5 miles east of, at southeast corner of bridge over

Klamath River, top of pier; aluminum tag stamped " B-198-1608 " 1, 610. 48

Oak Bar, 1 mile south of, west of road, in base of pine tree 30 inches in diameter; nail with aluminum tag stamped B-200-1635 " 1, 637. 17

Oak Bar; surface of water, September, 1907 1, 630. 00

Oak Bar, 500 feet east of hotel, north of road, in laige boulder; aluminum tablet stamped **B-B-1907-66-1660" 1, 662. 384

Oak Bar, 1.5 miles east of, west of road, in base of madrono tree 30 inches in diameter; nail with aluminurii tag stamped ' B-202-1683 " 1, 685. 31

Oak Bar, 3.3 miles east of, south of road, at Quigley's Ferry, in base of pine tree 30 inches in diameter; nail with aluminum tag stamped "B-204- 1699" 1, 700. 62

Walker, 1,000 feet west of post office, 10 feet east of road, in boulder; aluminum tablet stamped 'B-B-1907-67-1722" 1,724.255

Walker, 100 feet east of post office, in base of oak tree 60 inches in diameter; nail with aluminum tag stamped "B-205-1704" 1, 706. 27

Walker, 2.5 miles east of, south of road, in base of pine tree 24 inches in diameter; nail with aluminum tag stamped **B-207-1729" 1 730. 81

Walker, 3.8 miles east of, north of road, in base of oak tree 40 inches in diameter; nail with aluminum tag stamped "1758 " 1, 759. 96

Walker, 5.2 miles east of, south of road at bend, 10 feet east of dry bed of creek, in large bowlder; aluminum tablet stamped " B-B-1907-1810 " . . . 1, 812. 22

Gott\'ille, south bank of Klamath River at bend of road, in rock ledge; aluminum tablet stamped "B-B-1907-69-1882" 1, 907. 161

Gottville, 2 miles east of, 6 miles east of ferry landing, west of road, in base of oak tree 30 inches in diameter; nail with aluminum tag stamped 212-1858" 1, 882. 73

Gottville, 3.1 miles east of, south of road at bluff over river, in ledge of rock; aluminum tablet stamped " B-B-1907-70-1951 " 1, 975. 740

Gottville, 5.3 miles east of, 1,000 feet east of junction of roads to Yrekaand Hombrook; north of road, in base of pine tree 20 inched in diameter, nail; aluminum tag stamped "B-214-1948" 1,950.96

6.7 miles east of, north of road, in base of oak tree 10 inches in

diameter, nail; aluminum tag stamped " B-215-1963 " 1, 965. 46

, 60 SPIRIT LEVEIJNO IN CALIPOBNIA, IWH TO IttlO.

nail. 2,IM' Oottyjiio, i.tt mile* mcI of, 25 fM uurtli of bridge uviir Kkmaih River,

WMt cil ru*rl, in niL'k ledge; kliuuinuin Ublt "B-B~lM7-n-

am" 2,0ltM7

Oottvillf. Ill niUm mbI <A, ouutb u( nad, in bae <jf oak tree 40 inches in

tliamfltcfi 2.I1U.8S

UouUiufSWu Rivi-r; wait-r HurW-v. Oct 1. 1907 L',

liumiiruok, 4.3 niilw wcel of, siiuU) of roBil, in bare of oak tiee 10 ioiIice in

iliamctor: nail with aluminum U(; stamped "B-'217-2H4" 2, MS.GS

Uumbtuuk, 3 milea weel ol, north of mtd at juuctioD of rmd and river tnil,

in lai) bowlder; aluminum tablet stamped "B-B- 1907-73-2069" 2, 07L 44:

Hurubrook, Klamatfa River at, under bringing bridge; sur&ce of water

<lrt,3. 1907 2. ten. HO

Bornbrook. 0.8 mile nouth of, wet of railroad, 200 feet eouth of milepoat

aw. line; iron post Btamped 'B-ail-l-lWS" 2, 11S.2S

Honibronk, 2.1 milm north of, eat of railroad, 30 feet norOi of milfpotit

397. al rpuce line ; iron piet lam)>ed "2306-l)-1903'' 2, 306.813

sxiAD ai;Ai>&juioi.x. 0ottac Orair nortlwatl aloac to 6*lad. ttaano* *oatli*an to hIkkiI-

ttta (irove, 0.5 mili' nortli of, went of trail, 500 feet north of fimall

eUriun, in bowldi-r; aluminum tablet stamped " B-B-1S07-42-847 "' M&3t3

Collago Giove. 1,5 milw north of, eat of trail, 1,000 feet ireeC of mouUi of

ttidepandeocu Creek, in base of [Mae tree 24 inchea in diameter; nail

with ahiminum tae sUunped "B-ll3-10fl7" 1,0S2.

C.iiui-.' 1 lA miles ii..fih of. fai'l of Irail, 1,000 feet north of .New York

l!;i\ iiii', ill liL-i' ]ilji(' trii' IS ini'hea in diameter; nail with aluminum

(::M;iiiipf,l li-ll4-rJ4U" 1,236.56

1 W iiiili' uurih oi. L'o feot oa.-t of trait. loOfeet north of Craw-

Inrl I', 111 fi't'i imrili nf i lu.-torof jiiiie trees, in large bowlder; alumi-

luiiii |l-[(-i907-13-l-'90"' l,285.9K

t'liHui;!' (lrii\.', 7 mill'- north of, at Siskiyou mine, uorth of trail, on summit

iif liill JIH) fi.'1't iiiirih of mine, in base of pine tree 36 inches in diameter,

luiil; aliiiuimiin (ai; - ll-llT-1619" 1, 614.96

D.S Liiil.'s siiuih of. 40 (fit north of bridge over Clear Creek,

LI. loiLiiiry bowKii'r; ;iliiiiiinum tablet stamped '-3-11-19074-979" 974.863

i',.ti;,;;.-(itov<\ II.;! mill's [lorili of, oa.-'t of (rail. 200 feet north of cabin, in

liii-i' (>iiio \nv 10 inclu'ii in diameter; nail with aluminum tag stamped

li II!' Will" 1,032.32

lliippj rump, i.H miles south of, west of trail, 200 feet south of summit of

liitl. ill bowlder; uluiaiuum tablet stamped 'B-lf-1907-i5-lo3o" 1,531.026

lliijipy ('amp, 1.2 miles south of, 75 feel north of barn on Gride ranch, in

I'lise of oak tree 39 inches in diameter; nail with aluminum tag stamped

11 1147" 1,143.13

lliippv t'limp, MUilhwei't corner brick wall of Eclipse .saloon; aluminum

mbli'l stamped " " 1.088.456

I amp, 2,S miles north of. west of road, in base of oak tree 14 inches

ill liianieter; nail withalumitiutn tag stamped "B-127-I194" 1, 189. T6

Happy Camp, l.S miles north of, 100 feet north of summit of hill north of

I rail. iiin--k ledge; aluminum tablet stamped "B-B-l 907 -1727" 1,723.443

Oil this llni' a error ot I yunl bfiwwn Scoil Bar and Sfeaniber sohoolhome vaawbltnull.v iiiljmiwl Imiillj ui Wilkes ranch, where ftnutha yard error possibly exlsia.

PRIBiARY LEVELING. 61

Happy Camp, 8.7 milen north of, east of road, in laige bowlder; aluminum Feet

tablet stamped '*B-B-1907-4&-1232" 1,227,845

Nolton, 2 milen east of, 10 feet north of bunk house on Martin's ranch, in

lai bowlder; aluminum tablet stamped " B-B-1907-4-1296 " 1, 29L 472

Nolton,' 3.9 miles east of, south of road, nail; in base of maple tree 36 inches

in diameter, aluminum tag stamped "B-136-1341 " 1, 33a. 68

Lowden, in front of schoolhouse, in base of oak tree; nail with aluminum

tag stamped *'B-131386" 1,381.49

Seiad, 0.8 mile Kouth of east of road, on east bank of Klamath River, in

rock ledge; aluminum tablet stamped B-B-1907-55-1446 " 1, 448. 039

Note. — The line crosses here to the south bank of Klamath River.

Seiad, 3.8 miles east of, north of road, in base of maple tree 36 inches in diameter, nail; aluminum tag stamped " B-162-1437 " 1 , 438. 96

Seiad, 6.2 miles east of, south of road, 1,000 feet east of Burhardt's ranch house, in bowlder; aluminum tablet stamped "B-B-1907-56-1514" 1. 515. 633

Hamburg, 1 mile southeast of, 250 feet east of Willard house, nail in base of oak tree 24 inches in diameter; aluminum tag stamped B-165-1532 " . 1 , 533. 54

Hambuig, 1.2 miles southeast of, south of road, 1,000 feet west of mouth of Scott River, in large bowJder; aluminum tablet stamped "B-B-1907- 57-1547" '. 1, 548. 683

Scott Bar, 8.6 miles southwest of, west of road, 25 feet south of shed at Kleaver ranch, in.large bowlder; aluminum tablet stamped "B-B-1907- 60-2112 " , 2, 113. 660

Scott Bar, 10.9 miles southwest of, east of road, 25 feet north of bridge over Scott River, in laie bowlder; aluminum tablet stamped "B-B-1907- 161-2233" 2, 234. 835

Fort Jones, 15 miles west of, west of road, 1,000 feet east of Canyon Creek, on large bowlder; chisel point painted U. S. 177-2355 " 2, 357. 25

Fort Jones, 12.8 miles west of, 100 feet north of Wilke's ranch house, east of road, on large rock; chisel point painted "U. S.-178-2499" 2, 490. 27

Lowden north to Watkins, Oref .

Lowden, 0.8 mile north of, east of road, in base of oak tree 36 inches in diameter; nail with aluminum tag stamped B-141-1545" 1, 541.41

Lowden, 3.7 miles north uf, east of trail, at end of wagon road, in base of oak tree 48 inches in diameter; nail with aluminum tag stamped B-14: 1842" 1. 838. 38

Lowden, 6.2 miles north of, west of trail, 4.1 miles west of summit between and Eileen, in small quartz aluminum tablet stamped "B-li-51-1 907-4033" 3,927.926

Lowden, 7.6 miles north of. east of trail, 300 feet east of cabin on Wetzel & Well's claim, in base of fir tree 24 inches in diameter; nail with aluminum tag stamped 'lV-14r>-5340" 5,235.98

Eileen, 4.1 miles south of, on summit between Lowden and Eileen, 15 feet north of trail, in slate ledge; aluminum tablet stamped " B-B-1 907-52 6189" 6, 185. 403

Eileen, 2. 1 miles of, 250 feet south of corral, west of trail, in base of fir

tree 48 inches in diameter; nail with aluminum tag stamped 150-5446 " . 5, 442. 01

Eileen, 1.2 miles south of, 25 feet east of junction of trail to Blue Ledge and Eileen, 250 feet south of Sophia mine, in base of pine tree 36 inches in diameter; nail with aluminum tag stamped "1-152-4765" 4, 760. 59

Eileen, 0.3 mile south of, 0.3 mile north of Blue Ledge mine, east edge of rod, in rock ledge; aluminum tablet stamped ' ' B-B-1907-3829 " 3, 825. 352

Spirit Leveusg In Caufobnia, Iwit To Isio.

fHlwn. OK mih nf , 250 twt narfJi of liridgi uver auikll atmun. witt t Piad.in ImwufffiiiinrplnemeTliiDchniiiiduinRieT; naj} withiUunilnutn it

Ufi Mtauipmi -B-ifts-ssw a,akti

nuticm. etuilof mad. 2fiO fMt east of fltiiite, in mrk Mi; Juiiiliiuiu hibU-t sinmpwl '-Tl-I907-2127" 2. USLOM

VVnikirui. OmR., MX) [pxi laiiiTh pni (ifn<. lAO north of Appliit Creek, 670 twl iniliwit <rf comer of Mtra. 3fi and 36, T. 40 8., R. 4 W., and SK-B. 1 xnA 2, T. 41 S., U. 4 W., 10 fm-f wet of blggKle: imu poi KUmpod D-IINM-tWB'" l.S63,Sr '

Wmtkina, Orvg., 0,9 miln north of, 4 fool aoiilhrwrt of aniitliMat ntraia at choolhou!*, in Fivtl "f tjw; nail, , I.Mt.U

PKESTOK QUAD RAlf OLE. Torcuwa'a t*aiAi Bark to Cotter* .

tjommiilu'. H.8 milm iiorlli nrat Klftmalh Rivnr, tn baanofcttk

trp:t0inrlirtndiaiuelcr: nail wilhaluoiinuKiIi;aUujpml" ll-liKMIfil " 6H.TI

1 1 ,8 miles north of, buuIIi uf , 200 Boiilh nf niiall atrejun, aat. iif tjvil, iDsmuH ; aluminum taVilol al&nipd " Ii-B-lB07-39-

KotttM Bar, 13.2 miles north uf, SOO fevt aonit n( iiridiw over Hock ('roh, Kiiith of trail, in base nf oak Tree 14 inchm In dlttmeMr; mil wiih altiniinuiu \Mg Htamped ' 11-104-720 " 718. M

Bar, l3.8iiii1north uf, euituftmil. 0.5 mile hill, in base nf sugar Xree 36 inrhra in diameter; nail trith altnuinnin tag stamped "B-107-u:i3" 1,489. M

SoiDMiBar, 17 mites north of , O-SmUanorthofaunuiiit of Dillon UotUMfn, wi9( nf (rail, in small bowlder; aluminum tablet slapped "B-B-1907-

Siiii[..< Ikir, lit..') uiiloH iKirih of, 600 fcot north of summit between Dillon I'rci'k lotuii;*" east of tniil, in base of fir tree 36 inches in luiil wilh .ihiminum tug slapped - B-110-1261 " I, 255,50

(nll:ii:e (;r.n.-, l.,j iuilcM*.ulb of, 2,1 miles mirth of Dillon Creek, west of Irail, r'..rniT<.f at ran.'h. in laie aluminum Oh- Ii'l Mtaiiipcrl 780.8:7

linivv, 15 miles siiulli nf. river at J, Aubrey's ranch; anrfaceof

waler, .\uirusr, 750

Cntraj.'eUrdve, 0,7 mile smillHif. 21,2 iiiilemiorlh of Somes liar, east of trail. tit kiseoF 12-inrh forked mudrcnelree: nuit wilh aluminum taR stamped lt-1 1 l-SWI" 882.13

Etna Hiu.S Quadkahole,

Point e mUei northsail of Etii KUIf tonthweit to Etna HIUi, Uwoca Bortb.

Kliia .Mill,', :l,l! miles imribeaslof. Hi feet nnrtli of mad. in bowlder; ahimi-

num liililel slapped l(-l!HI7-10-27T8" 2. 775. 356

Hina Mills, 2,2 miles east of, at wmlbwest onmer of bridge over Srott River,

in nrKiralx.vepier: spike stamped "B." ahiminum lass'amped "B-SO-

:;7iir' 2. 7S6. 89

Etna Mills, 2,2 miiee east of, Seott River, imder bridge; surfaee of water,

June 14, IDO? 2. 776

Kina Mills, norlheasl comer nf Blake'hotel in brick wall ; ahiminum Uhlet

stamped "li-1907-ll-29;J3" 2,930.372

Etna Mills, center of Denny Bar ('o,'s store, in front brick wall; aluminum

tablet stamped "B-1907-12-2946" 2.M2.072

Primary Leveling. 68

Green view, 2.4 miles south of, west of road, 25 feet south of Washington district school, in base of pine tree 36 inches in diameter; nail with alumi- Feet num tag stamped "B-193-2816" 2,816.49

Etna mill soathweit to Snowden.

Etna Mills, 2 miles southwest of, at forks of road to mill, in base of pine tree

24 inches in diameter; spike with aluminum tag stamped " B-33-3122 " . . 3, 117. 98

Etna Mills, 3 miles southwest of, north of road, in flat rock; aluminum tablet stamped ''B-1907-13-3443'* 3,439.800

Etna Mills, 5 miles southwest of, 6 feet north of road, in base of pine tree 36 inches in diameter; spike with aluminum tag stamped "B-35-3864" 3, 861. 70

Etna Mills, 5.8 miles southwest of, east of road, in granite rock; aluminum

tablet stamped " B-1907-14-4243 " 4, 244. 170

Etna Mills, 7.7 miles southwest of, 300 feet north of bridge, 20 feet east of road, in base of fir tree 24 inches in diameter; spike with aluminum tag stamped "B-37-5156" 5, 151. 25

Etna Mills, 9.4 miles southwest of, 20 feet east of road, at summit between Etna Mills and Sawyer Bar, in slate ledge; aluminum tablet stamped '' B-1907-15-5969 " 5, 965. 470

Summit, 2.9 miles west of, on south edge of road, in rock; aluminum tablet stamped ''B-1907-16190" 4, 187. 696

Summit, 5 miles southwest of, at north edge of road, 1,500 feet west of small bridge, in base of fir tree 48 inches in diameter; nail with aluminum tag stamped ' B-4 1-3450 " 3, 446. 15

SAWYER BAR QTTADRAKaLE. Snowden wegt alone road down Salmon Rlrer to Somes Bar.

Snowden, 0.6 mile west of, 400 feet west of bridge, west side of creek, north

of road; aluminum tablet stamped "B-1 7-1 907-2979'* 2, 974. 612

Snowden, 2.4 miles west of, in southwest comer of steel bridge; bridge

spike with aluminum tag stamped B-44-2598, " spike stamped " B ". . . 2, 593. 73 Snowden, 5.3 miles west of, 10 feet north of fork in road, in large bowlder;

aluminum tablet stamped " B- 1907- 18-2425" 2, 420. 440

Sawyer Bar, east end of. north of road, in large slate ledge ; aluminum tablet

stamped B-19-1907-2173 " 2, 171. 794

Sawyer Bar, 3.1 miles west of, north of road, in rock ledge; aluminum

tablet stamped B-1 907-20-1 995" 2, 022. 460

Sawyer Bar, 6.1 miles west of, north of road, at entrance to small gulch,

in granite jock; aluminum tablet stamped "B-1907-21-1787" 1,914.360

Sawyer Bar, 8.9 miles west of, south of road at cut making horseshoe;

aluminum tablet stamped " B-B-1907-22-1677" 1, 716. 340

Sawyer Bar, 10.9 miles west of, south of road, in base of live oak tree 14

inches in diameter; nail with aluminum tag stamped *'B-54-1429" 1, 456. 71

Forks of Salmon. 2.4 miles east of. north of road, 500 feet west of bridge, in

rock; aluminum tablet stamped " B-1 907-23-1484 " 1, 511. 430

Forks of Salmon. 400 feet east of Bennett s store, north of road, in bowlder;

aluminum tablet stamped " B- B-1 907724-1 2 14" 1, 241. 884

Forks of Salmon, 3.2 miles west of, 400 feet west of old Hyde mine, south

of trail, 15 feet from edge of bluff over river, in large bowlder; aluminum

tablet stamped *'B-B-1907-25-1124" 1, 151. 340

Note. — The line crosses here to the southwest side of Salmon River.

Forks of Salmon, 5.8 miles west of, 600 feet east of small bridge, south of trail, in large bowlder; aluminum tablet stamped ''B-B-1907~26-1208'*.. 1,236.894.

K SPriUT l.KVEI.INO [N CAUFORNU, 1907 TO IMO.

milt* wmn nf, GOO fwi nonh ol mtnunit btirMi

ol Sulnxm uid ButUent Flat, cut in UrKe bowlder; klntnuium

iabl<*t "U-aiSfir J7-aiMI " 2.U&ai

liittlrn Flat, 0,4 mile wiwi o(. iwrlli of nmd on oiign nt bluH, in late bowlder; iluaitouiD tublrl i-uuiipwl " B-B-I907-ZH-868" gaZK

liittlirn FUt, 1.9 milw u(. outb of mil, ld bosn of m&dmn irav 21 indiM In dlaiuelur; Hpiko with uluminiim ten 'Umped "It-7n-IGI6".. l,6W.fl

tuttlcm Klt, 3 milm wwi o(, 3.04 milm tsut -it Buuunti PUt and liar. 1& ((it north timid. in bowlilor; luniinuin lAblvt Hbimptil - I.TIAS

omtm Bar. 51) (eel wtBt uf Hlore; point on rook, painlod "ail" S&O

BOOPA OtIADKAHaLE.

omw Bv, 0.0 miln of, north nidc of Salmou Rivnr, Houtli trail, in bMe ol nudrciiii) tree IS liicbei ill diamelcr; nnil with aluminum (jtg

tIiIid"B-flS-5.Sr' WT-

.MtiM Dw, 4 lnilH> north uf. wuot of Intil, in bam of tr £4 inches in diuncrtcr; nnil with idumiiiuiii tag alamped '' I,4M.

inniM Rar. 4.3 milM Donh of. uoet of tri], bctwitt two niutll streuna. in bi);uliuniuum tablet etiimpeil "B-B-lWI7-:(7-149S" I

Sornvd Gar. 11.7 mllee north of. J. 7 milan Boutb of Torgerson'a r&nch, wiwi trail, in biuw of onk 24 inches in diBDieier; nail with alitmintun tug stamped ' ' B-99-699 ' '

gom<!s GsT, S.3 miles nirlh of, 150 foet north of coml near bridge over Bmull Btresm at Torgerwm'a , in top of l&tge bowlder; aluminum tablet Htarappii " B-n-l9n7-33-6S0" fiT.. 431

TiirfTiTunti s ratiHi. Klamath Rivpr; Burtaop of water, August 12. 1907... 591

to point T.S mUt Siini™ Uiir. mile wi'st i)(. of Ir.iil. in largo bowlder; aluminum

'n-ll-liWI7-.iCil-,K)' ,588.046

Jiirirtion Siilmmi iitid KUimulh rivers. 0.5 mile south of. at bend in trail.

ivesi .if iMii. in liowldiT: aluminum tablet Btamped 'B-B-1907-31-503". 526. 8M Siimi's liar, 3.2 milfti we.st of. north of tniil al eiljre of over Klamath

Klver, in Imi'e of onk tree 12 inches in dinmerer; nail with aluminum tag

stamped - U-7il-N0!l 830. 73

Orleans. 2.0 milen east of. 500 fi><'t eaat o( Reise'a house, west of tmil, in

largo bowlder; aluminum tablet stamped 'll-B-l!l07-32-869" 889.830

Orli'!;iris. 1 mile euHl of, 23 feer esist of htackamiih shop at Perche'e raneh.

north of (mil. in lease of madrone tree 24 inches in dinmeier; nail with

alnminiim tagHlamp-'d "ll-Tit-o:!?" ,558.28

Orloaiis. 0.5 mileoasl of. north of trail. 100 feet east of ford, in large bowlder;

aluminum uM,-\ stamixHl " II II-1907-33-372- 392. 901

\oTB.— The line >'nite,- here to the north side of Klamath River. Orloimn, 2.3 mile- -o't of. !uiih of imil. in ba.'e of madmne tree 6 inehea

in dUimeler; nail vvilh aluminum tii .-tajnpod " B-81-122" 441 18

Orleans, 5.5 mill's wed i>(. iionli of trail, in bowlder; aluminum tablet

slampwl " It It l!K17 ;H li: I 694. 887

Orleann, 8.0 mili> of. trail, in ba.-'e of madrone tree 30 inches

in liam.'liT; nail with ttluuiiuum lag jumped 'B-86-39e" 417.63

Orlean:-. 10 miU-. wwt ol. tw o( bri.lge over Bluff Creek, west of

trail, in large bowldor; alumiiium lahlel stamped B-B-1907-3S-326".. 346. 760

Primary Leveling. 65

Witchpec, 3.5 milea east of, south of trail, in base of tan oak tree 56 inches Feet* in diameter; nail with aluminum tag stamped B-86-381 " 402. 02

Witchpec, 0.9 mile east of, south of trail, in base of oak tree 24 inches in

diameter; nail with aluminum tag stamped ' ' B-90-393 " 414. 16

Witchpec, 250 feet south of Rippey's house, 20 feet south of trail, 900 feet north of junction of Klamath and Trinity rivers, in large bowlder; aluminum tablet stamped " B-B-1907-36-346 " 366. 950

Note. — The line here crosses to the south side of Klamath-Trinity River.

Hoopa, 7.5 miles north of, west edge of trail, in slate rock; aluminum tablet stamped " B-B-25-1906 " 1, 006. 208

Note. — The remaining bench marks in this list are republished from

Bulletin 342.

Point near China Flat along road to Hoopa.

China Flat, 6.3 miles north of, on west edge of road, in rock; aluminum

tablet stamped B-B-21-1906 " 1, 354. 915

Hoopa, 2.4 miles south of, 1,300 feet south of mile tree 63, 1,700 feet north of bridge, on west edge of road, in bowlder; aluminum tablet stamped ' ' B-B-22-1906 " 386. 042

Hoopa, 1,000 feet north of Bigard's store, in right edge of steps to United States Indian agent's office; aluminum tablet stamped **B-B-1906-23- 352" 35L270

Hoopa north along road and trail 7.6 miles (single spur line).

Hoopa, 3.2 miles north of, 150 feet south of Soctish Creek, west edge of road, in rock; aluminum tablet stamped "B-B-24-1906" 308. 482

Hoopa, 7.5 miles north of, on west edge of trail, in slate rock; aluminum tablet stamped B-B-25-1906 " 1,006. 208

Hoopa son th west along trail and road, to forks of road 3.4 miles northwest of Berry

ranch house.

Hoopa, 3.8 miles west of, 20 feet west of Fourmile Creek, in large bowlder;

aluminum tablet stamped **B-1906-17I6 ' 1, 715. 199

Hoopa, 6 miles west of, 10 feet south of trail, in bowlder; aluminum tablet

stamped 'B-l 906-27-2899" 2, 900. 323

Bear's ranch, 4.5 miles east of, on north edge of trail, in highest point of

nxk; aluminum tablet stamped ' B-1906-28-3495 " 3, 494. 856

Capitola, Morgan Hill, New Almaden, Pajaro, Point Sur, Salinas, San Jose, and

Santa Cruz quadrangles.

Alameda, .Monterey, San Mateo, Santa Claka, And Santa Cruz Counties,

The elevations in the following list are based upon an adjusted height at San Jose published in Bulletin 342, and accord with precise leveling along the Southern Pacific Railroad main line published in the same bulletin.

Leveling in all of these quadrangles, except Point Sur, was done in

1908 by B. A. Jenkins. Additional work was done in the Salinas quadrangle in 1908 by T. H. Moncure, in the San Jose quadrangle in

1909 by L. F. Biggs, and in 1903 by S. E. Blout, and in the New Almaden and Santa Cruz quadrangles in 1899 by C. C. Ward. The leveling in Point Sur quadrangle was done in 1909 by L. F. Biggs.

The work of 1908 and 1909 was done in cooperation with the State.

95094°— Bull. 481—11 5

Etiiltniu. t.t tmOm KMifc Ht ia oM mI oI 'U-IOK:'* mlUBinnm

UUnKmnipMl*-aP.MIMa" e

AjMna, Lit mlw wuli o(, SBO lM Mlb of BitcptM 10ft. b ad of

culvn. V.nimsZ" i

AptoB. 1 mitoaailhot, end oi cnlTMt Ill-F. aluiaiDuni ubMsuinped

-S. F. 104 IMS 23"- . - - It

Afitm, I. Ml bet muli M Wtinti. aat of tfak, in aouh abutmeoi of aow

lumiDumuiOFtBUmpfxl-S. F.19m24" B&a(

Aptitf, mfronlof itBlion: top of nil.. M.i

CmpiUttm, O.i laiiK math tA, ocicTiI%-e 11&, caot cadi f !iiilri1 rirH-tt

-U.a.lU. N. No. fi" 67.

(phoh, introntof lUlion; tofiaf mil MS

Capitola, mila north of, mat of tnk. iwriL ad of new sucl brii in

canntabutBimi: klumbum table* aUrapud "S. P.&S IMS 25" M.7M

CapHola. 0.9 mik- tvartb of, mi off cad of cohrtrt -B; dfde

DelHar, hi tromiofMatioti: top of nil 5&B

SASTA CmVZ M' aOADSASOLK. Ill Wju to Cnu. Ib*ii north I hOM-

Snbri;.'})!, in (rout of BUIion: lop of rail MS

Santa Viii:. 0.9 mile nonh of stMion, at amitheMt ranter of Son Lontuto

ISiv.r l.riiU-P, ingiwirdPiil; boll head psintpd "U. 9. 2S D.M. N. 45".. 2S.14 SaiiUi Oij;, lm fcol ii'>nK of In Southern Pacific Railroad graas

lil.Fi. iroi, .Hr;in]|H'<i -S. K. 14 I 2G"' 13.570

Siiiiiu 1 ruz. i.-jst sidi> 'if t-Tiirarice to Santa Cruz County courthouse, in base

Hurit:i I'nu. iiorthwci'l coriitT oi brii'k biiildiiis facing Pacific Avenue, next buililiiii; of courtlioi]:%: alutniiuim tablet stamped "S. F. 18 17.269

Santa I'riiji. 2.x inilfs nordi of, west end of cement culvert; chiseled circle

painlPii -v. S. 171] [I. M. -IT" 169.50

SAN JOSE 11' QUADRAHOLE. Irvlngton lontb aloag Soutbern PhcIDc RUlKmil to San JOH.

Milc[">si:i7. j.u-i - HiJm U" 46.703

Mili'piisl -111. 3.1 ti'ci Hoiitli of, Hmali bridie. ent ?ide of back; !"t stampeii 'll.lWJl F!" 11.465

Mill-post -lii, 475 feet aoulli of. at highway crunaiiiK, west of track; iron poet . ;{7.5IIJ II " 37. 694

Milepost oil, 50 feet east of, east of track; iron stiuiiiMxl '09.117 B".. 69.330 At San JoH.

San Jose, 150 pust of Southern Paeilic itailrojid Bliindard-stare Btatioii, in ['irculiir haHo of iron n-aler uraiid about 2 feet in dianieter; lo<; bolt (Const and tJeodetic Survey bench mark) 9L78

San Jcise, Mouthwest corner of St. James and First nlreel.'*, o;i|)oeite St. JanicB Sijuare, set lioriKonlatly in west end of lower eci'e iif alone banister on norlli side of entr.iiii'e to Santa Clara County Hall of Itwonis: aluminum table stamiwd "UMS. F." 98.317

Pbimaby Levelinq. 67

StA JoM sontheait along rallroa4 8.6 mttet.

San Jose, in northeast corner of Trinity Parish Episcopal Church; alumi- Feet.

num tablet stamped S. F. 98 1908 30" 97. 264

San Jose, at 21 North Fourth Street, in southeast comer of brick warehouse

and ofHce of Sperry Floiu- Co. ; tablet stamped S. F. 96 1908 1 " 96. 11 1

San Jose, 2 miles south of, 300 feet north of brickworks, west of railroad, in

base of semaphore; bolt head painted U. S. 112 B. M. No. 1 " 112. 47

San Jose, 3.5 miles south of, 50 feet west of milepost 54, west of track, 400

feet north of Franklin schoolhouse ; iron post stamped S. F. 130 1908 2 " . 130. 490 San Jose, G.5 miles south of, west of track, 50 feet west of milepost 57; iron

post stamped " S. F. 176 1908 B" 175. 7!)0

Eden vale, in front of station ; top of rail 183. 5

San JoM southwest along Southern Paolflc Railroad to point 8 mUes north of Los

Gatoi.

San Jose, in front of narrow-gage station; top of rail 96. 6

Campbell, in front of station; top of rail 199. 7

Campbell, 1.1 miles southwest of, 100 feet east of tank, in cement culvert;

aluminum tablet stamped ''S. F. 225 1908 35" 224. 902

Vasona, in front of station; top of rail 276. 1

NEW ALM ADEN 16' QUADRAKQLE. Point 8.6 milas lontheait of San Jom to milepogt 61.

San Joee, 9.7 miles south of, 800 feet south of milepost 60, 50 feet north of road to Mrs. L. Little's ranch house, where it crosses railroad, at west edge of wagon road; iron poet stamped F. 199 1908 4" 198. 764

Pomar, in front of station; top of rail 205. 1

Point near Zeyante north to point 1 mile north of Los Oatos.

Glen wood, 1.4 miles southwest of, at southwest comer of tunnel 4, in wing;

aluminum tablet stamped "S. F. 787 1908 B. O. " 786. 985

Glenwood, in front of station; top of rail 888. 96

Laurel, in front of station; top of rail 899. 3

Wrights, 1.4 miles southwest of, at west end of tunnel 2, in wing; aluminum

tablet F. 902 1908 31" 901.151

Wrights, 0.2 mile west of station, at northeast end of tunnel 2, in wing;

aluminum tablet stamped *'S. F. 898 1908 32" 897. 847

Aldercroft, 300 feet south of, on northeast comer of cement culvert 60-A;

chistled circle painted 8. 731 B. M. No. 61 " 730. 45

Alma, 0.8 mile southwest of, 400 feet south of private road crossing, west of

railroad, in bowlder; aluminum tablet stamped ''S. F. 621 1908 B. 3". 620.944 Alma, 0.6 mile northeast of, opposite Lexington, in cement culvert ; aluminum tablet stamped "S. F. 535 1908 34" 534. 652

Los Gatos, 1.1 miles southwest of, on cement culvert; chiseled (circle painted

*-U. S. 428 B. M. No. 64" 427.76

Los Gates, opposite station, in east corner of yard around Hotel Lindcm, on

Santa Cmz Avenue; iron post stamped "S. F. 412" 411. 789

MORGAN HILL 16' QUADRANQLE. miapoft 61, near Pomar, southeast along Southern Padflo Railroad to Ollroy.

San Jose, 12.5 miles south of, 0.2 mile north of Coyote, 150 feet south of road crossing, opposite milepost 63, west of track; iron post stamped "8. F. 2531908 5" 253.189

F

8PIIUT LEVEUKO IK CAUfOHNIA, IWH TO

amtk el nOnta naming; irun prat stunprnl "S. F. 300 1B08" sui.

S milM fnutb of. Mt ol tnt-k. 30 leet nut of milpptin ffl, 100

*wi ivf Mwlnme piat uinc-c; iron port vUmped "S. F, 314 I90B 7" s.

ilwlrunr. in ( uf elaiiini; top of nil

ilnrifan HiH, in (mot otuwioit; top of nil 34g;

ilorffui Ilill, 1.3 mile* uuib of. mm of Uck, 10 Iet ainith mllepmt 72;

iTT.n post (stamped "S. F. 3S21B0B8" , ayt ,

ri-niumt. in fronl of sUtinn', top of mil 33L0'

Martin, in fronl of titslion; Iiof nil 287. t

organ Hill, 4.3 milrs murh of, east road, tO Im-I isiet of milvpxt 75,

50U (ef( uuTh Maniu KbooUiouie; iron pot 8Umpi<<t "S. F. 380

1908 9" *;9,j

Rucker. in frwii ol vtAtion; top of nil ,.. 212,0

Gitroy, 2.8milcDor11iof, fifeetMuthof milppoet 7S, Mfeeteouthof priraie

road rriMsing; iron post aUmpctl "S. F, 224 190810"...

Gilmy, in southraet oonier of city h&U; alunuDum tablet stained "8. F.

tiilroy, in Southern PariGr Railroad graai plot, wmt of , 100 leet

Houth of (nation; iron nlaniped "S. F. IBT 190S 12" 19", 01

Gilroy, in front of station ; rop ii( mil 196. S

PAJASO If aUADBAKGLZ, OOmt MMtk aad WWt aloac Sanlhnn PaoMc to WataoBflll*.

ramadero. in front of station ; top of rail 1 71 ,1

tiilrny. 3.2 miles Boulii of. WJ i':ci soucli of milepofit B4, south of track; iron

|)<)s( Mampoi! "S. F. 167 KKISIS" 166.653

MilliT, in friinl of station: Inp of rail 156.5

(iilroy, HA miles soiilli of, 0.2 milo east of Sarcnr, south of track. .tO feot

wcPl of S7; iron poal stamped "S. I- V.iS 1908 14" 137.862

SiirKi'iilii, in fninl of station; top of rail 139,2

Sarni'dlM. 2.S miles wi-sl of, north of track. 170 Icpt east of milepost 90; iron

siampcii ".S. F. 144 190815" 144,080

I'lijiii'ddcii, in front of slalion; top of rail 12S. 6

liiiiic'iidcn, 1.7 miles wesi of, U.50 feci west of milepost 93. 900 feci ca*( of

rik rriishor, south of track; iron stamp<-d 'S. F, 124 1908 16" 123. W8

l.i:i;;iii, in friiTir of station; rop of rail 117.2

.\riiiti:L;', ill front of station; top of rail 9S.3

( liilic'iiiliii, 4.8 miles west of, south of (rack, 'Ai feet south of milepcct 36;

iri.ri iMiHl stamped "S. V. 60 1908 17"' 66.22'

V..K11, ill fninl of t'liilion; I np of rail 62.0

I'tijiirr., I I miles oiiMl of, 20 feet we.Ht of milepi.ti 09; iron poal slam ik-cI "S.

;ifi imwix" 30.372

I'iijiiro, in front of station; top of rail 20.7

W i.iHoiiville, O.r, mile south of, at northeast corner of Pajaro bridge in top

..f |,j.t; idinniuuin tiililcl slamjjcd "S. F. 3imi08 19'' 29.567

ville, ii> trotit of station; top of rail 26. 9

Pajaro lODth to point 0,( mll< lontti of Cutrorllle.

l'MJim>, I K miles ivnilli of, Titl fM-l we-t of mitepOBf 102, on line lietween rn;hi oi Huy mid county road; iron post stamped "S. F. 19 1908 37" 18.777

Primary Leveling. 69

Pajaro, 4.8 miles south of, 100 feet north of milepost 105, at east edge of Feet.

track; iron post stamped "S. F. 3 1908 38" 3.518

Elkhom, in front of station ; top of rail '. 8. 3

Pajaro, 8.1 miles south of, 2.4 miles north of Castroville, 800 feet south of

milepost 108, east of track; iron post stamped "S. F. 21 1908 39" 21.091

Castroville, in front of station ; top of rail 2f . 5

Castroville, 0.6 mile south of, 400 feet south of milepost 111, east of track,

opposite south end of Y; iron post stamped "S. F. 20 1908 40" 19. 519

Salinas 15' Qitadranole.

Point near Castroville lontheaBt alone Southern Pacific Railroad to point 2 miles

southeast of Chnalar.

Salinas, 5.2 miles northwest of, 20 feet north of milepost 114, east of railroad; iron post stumped "S. F. 28 1908 41 " 28. 117

Graves, in front of siboard ; top of rail 36. G

Salinas, at south end of steps at east entrance to Salinas High School, in cement banister; aluminum tablet stamped "S. F. 53 1908 42" 52. 957

Salinas, at west end of steps at south entrance to Monterey County jail, in stone banister; aluminum tablet stamped "S. F. 53 1908 43 " 53. 413

Salinas, in front of station ; top of rail 48. 8

Salinas, 200 feet south of station, at north end of Southern Pacific Railroad

park; iron post stamped "S. F. 49 1908 44" 49.325

Salinas, 4.6 miles southeast of, 100 feet west of milepost 123, on line between right of way and county road; iron poet stamped F. 68 1908 54" 67.986

Spence, in front of station; top of rail 84. 3

Spence, 0.6 mile southeast of, 10 feet north of milepost 126; iron post stampede's. F. 91 1908 53" 90.088

Chualar, 0.2 mile north of station, 20 feet south of road crossing, at north edge of town, on line between right of way and county road; iron post stamped *'S. F. 109 1908 52" 108. 117

Chualar, in front of station ; top of rail 102. 2

Salinas north and northwest to Castroville.

Santa Rita, 0.5 mile north of, at road junction; iron post stamped "S. F.

115 1908 45" 115.401

Castroville, 0.7 mile south by 1.7 miles east of,_7.1 miles northwest of

Salinas, at north edge of road; iron post stamped *'S. F. 61 1908 46 " 61. 074

Castroville, 0.6 mile south of, 400 feet south of milepost 111, east edge of

right of way, opposite south end of Y; iron post stamped ''S. F. 20 1908

40 " 19. 518

Point 3.8 miles north of Salinas east to Nativldad, thence south to Spence.

Salinas, 3.8 miles north of, 0.4 mile of Santa Rita, at road junction;

iron post stamped "S. F. 1908 45 115" 115.401

Natividad, 100 feet south of saloon, at fence comer; iron post stamped

"S. F. 161 1908 57" 160.809

NatiNidad, 3.7 miles southeast of, 0.5 mile south of limestone quarry, at

angle in road, at east edge of road; iron post stamped *'S. F. 185 1908 56". 184. 652 Spence, 2 miles northeast by 1 mile north of, at east edge of road; iron post

stampedes. F. 133 1908 55" 132.920

IPmiT I.EVKI.INO !N CAUFilHNIA, IW' TO

H lOltkMM or SkUau (OBtllwMI to Spncklfi. a *ut to OhiuJv.

SfitiTkli-". 2 inili-B muthfjiBl of, AC feet SLimh . fm. 'I>]iri((' Il&rkin't ranch bouiie; iron prist Ktampmt "S. 1808 47",., BiW offico ol prvcklfii Supa Co.. nl anath pjid Mepi at main suit bHiiiotrri Blummam UbUl stunpMl f. 02 1908 4K ". (iV M

AltwHl lIuiwn'B ranch boUM<, 3.2 mllM norihwtKl of, 100 fwi wput of ftirlw of mad, ill fi-; inm pout sUmpt-d "S, F. 81 1908 'IS" SO rm

rlitialu, 23 inilee sudthwrat by 3.1 tniU-s nnrlbwral of, p[)UBit Albol llniiBi-D'R mni-b bonw. &t I nf ; Iron prjul "S F. 90 l!W8M " -- Kiora

I'hualu. 2.3 DiileB soulbwmt of. luolhtnwt angle of fork rciod, al WMt tMmi-r ii( iiiii Htiwl bridge over Salitiu ', in (trtaifal pipr; daminHm lab-

PolBl uu SprHklei toBtliirui knd idntk to WMUsctaa Behool. Ussee sut to L.1B-

Sjirockles, i:,2-=> mill's wit by I mile south of, noiih of iDod.oppfeilrH-roni)* road froiu miilhnast; iron jwbI Etampn} "138 104" l:t, H

.(irecktw, 3 mile wotil by 2 milwsijuih of. in cntiruf rutd, inalJi nde iiF blBEcd eyvatntiTp [m>; ptuoled uati and aluiDiDiiiii ig mukvd "triA 105" Ift5.;5

Spn-(k!e, near Toro freek; surtire of water in, I5eplt'inb 8, 1908 Iis.i

Spreckles, 4.5 milpewesl by 3 mileeeouth of, inaoTilhwesKorkaof jiiuction <jI UouUny and Saliuaa and Canal De Hem. toads; iroD post abund "MIIOT" xLiS

Wo-ibinelon scho"l, in yard of, at southeast comer of arfiaol; iron |)sii siamiwil 110" SaiB

l.iiiriilii si'hniil, in yard of, at comer of wool; iron post stamped

951 113" 951. 1S

lijvidc u[ iK'ud i>[ I'in (.'aDyon, in northwest comer ufroad forks at di\-ide liHweon ('omd De Tierra (valli-yt and Pine Canyon; iron post stamped

rill.' i'linycin, mdilh i.f. ."lOO fwt west iif \V. V. Brady's ranch sharp I urn i.f riwl arinind pninl, on lower side nf road; iron poet stamped '652

Ctaualsc toDttaveit to A point U nilai lonlbciit D( Chnalar bildc.

1 hiiaUir, 2.(i mill';' wcl nl, T.i fci'i wi't .f bride'c ovi'r Kalina? River, at irinri'i'li.in nf nurlh-s-ailh ruad, :il feme line; imii piel "100 B

urns n-.i" 99.631

POIMT SXTR SO' OtJADKAMOLE,

CbualM (outhwoit ind louUKiitt to point 4 milei lontliwett of (poruon o(

hat I.

Chiuilar liriilne, 2.4 miles snulhca.-! -l. NK) fcM N.iiih of road to wesl. on eiim side uf rfiad, in lease of forked oak free; copper nail scribed and imiiiied '147 H.M.13' 147.24

<'hiiatiir bridge, 3.5 miles southeast of, west side of rigid, opposite Wooster hoiiPc, 0.5milciior1hof iron post s tarn pi-d "132 B B.4" 132,016

PRIMARY LEVtlLING. 71

Cape San Martin, Paraiso Spring, Priest Valley, and San Miguel quadrangles,

and Gonzales 15 quadrangle.

KERN, KINGK, MONTEREY, AND SAN Ll'IS OBISPO COUNTIES.

Tlie elevations in the following list are based upon precise leveling along the Southern Pacific Railroad.

The greater part of leveling in the quadrangles of this list was done in cooperation with the State in 1008 by W. H. Monahan. Additional levehng was done in 1909 in the Paraiso Springs quadrangle by L. F. Biggs.

Gonzales 16' Qitadranqle.

Ctaualar Boutheast alone Southern Padflo Railroad to point abont 1 mile sontheait of

Oonsales.

Chualar, 1.2 miles southeast of, west of road, 50 feet from railroad, in telephone poUs spike with aluminum tap; stamped 108 '' 107. 70

Chualar, 3 miles southeast of, 20 feet north of railroad milepost 132, west

of road; iron post stamped 'TAL 1908 114 B" 114.220

Chualar, 4 miles southeast of, east of road, 5 feet north of bridge, 50 feet from railroad, in telephone pole; spike vith aluminum tag stamped '113" : 113.12

Chualar, 5 miles southeast of, west of road, in tele])hone spike with aluminum tag stamped 117.28

Gonzales, north edge of town, in comer of fence line between main highway and railroad; iron post stamped 1908 126 B" 125. 545

Gonzales, 1 mile southeast of, east of road, 50 feet east of railroad, in telephone pole; spike with aluminum tag stamped " 139 138. 97

San Migttel So' Quadrangle.

Point 8 miles sontheait of San Ardo sontheait alons railroad to Bradley, thence north-

eait alonf hifhwaTs to Stone Canyon.

San Ardo, 4.3 miles southeast of, east of railroad, in telegraph pole; spike

with aluminum tag stamped ' ' 461" 460. 30

San Ardo, 5.2 miles southeast of, east of railroad, in telegraph pole; spike

with aluminum tag stamped "491" 490. 17

San Ardo, 6.5 miles snitheast of, in base of target 1897; aluminum tablet

stamped **1908-i93-B " 492. 283

San Ardo, 7.3 miles southeast of, west of railroad, in telegraph pole; spike

with aluminum tag stamped "501 " 500. 18

San Ardo, 8.21 miles southeast of, in foundation of relay post; spike with

aluminum tag stamped "493 " 491. 89

San Ardo, 9.2 miles southeast of, west of track, 100 feet from river bank, in

tolograph pole; spike with aluminum tag stamped "507 " 505. 79

San Ardo, 10.1 miles southeast of, in stone culvert under railroad; aluminum tablet stamped "504-B-1908" 503. 171

San Ardo, 11.35 miles southeast of, on west side of railroad, in telegraph

pole; spike with aluminum tag stamped "518" 517.05

San Ardo, 12.2 miles southeast of, east of railroad, in telegraph pole; spike

with aluminum tag stamped "525 " 524. 34

Bnulley, north edge of town, in comer of line fence, 20 feet west of railroad,

1,000 feet north of grain shed ; iron post stamped "CAL-1908-l-B ". . 540. 248

nH BI'IRIT LRVULLVO IK CALIFOKSU. IWK TO UW.

Imdloy, infroDiuf iBtimi; nil maikMl "MS" iull'

tnilliiy , aiiuih iiifi idwu, in pimwt nf fitnre, 200fti omiIA of iwd MCtiun

bniwo; iron poat

tmilloy, 3 8 MnuifaoaM uf, u( roMl, in baas of kqpi rk tmr;

pilco with ftluminum 7mS

tiuilky, 4.1 miln* Miiithrauit nt, ilnnh of rutu!. kt hue irf hill, Id lat wli

tree; )itkn with Btuminiini lae "8D2" ,, st] tl

ItwUey, 4.9 mile* (wt t>(, ncirth nf lOO tet Mt ol wk ubk, od

liiiv Ihicu; iron >Uiiiippd "1021;" ., l,<at,ni

Intdley, 6.1 milet> is't of, Kiulh nwi, in baM of bhuU iMk tnti; pike

Aluminum Iak ""P'xl "li'jfl" I.iSS M.

Imllcy, M tiitim MMt ol, north ol nitnwd, 1,000 nsl o( nwd croEsini, in

tfk'empli ])oli'; epic wiih Kluminum U;k " 11106 " l.OOr.JI

ImtJli-y, D.l milm cut of, north of railmaj. 0.5 miic cnsi of the H&milion ratirh dvetlln);, lu toltvnph jnle; spike with aluminum tag slmmpeil

1074" 1.073.0

(Iradley, 10.2 milM eMt ol, Mutli of milnwd, 10 feet west of lar- uk ires;

iron 1.1241*

ttraiilcy, II. :i milweMtof, north of railroad, 100 fet north of railroad cui ant) 100 ((wt iMulh of liidiiu Creek, in telegraph poW; spike vita

aliimitium tBglAnipd "UTI" - 1, 170, U

Uruilley, 13 miles eaft of, iiorth of railroad, iOO fwl north of md cruMiing,

in IdRraph jmle; spike with aluminum lagBUinped '12T3" l.JTA tS

Itrudley, 14.2 milw eat of, norlb of milnnd. beiwMm highway aud railluul, 100 tLi'l ewit of rood lud ntilroud bridge, in pole; jijuke .

with ftlumlBuni tag rtunpod "1343" UMlSq

Rrdlcy, l.S milw eaHt ol, wmih of road. 100 north of railroad and 15

Iri-x S11111I1 of ?mall liak tree on ?outh ide of road, 100 feet north of pilch,

riiirlh lit nil (U-trick; imii I stamped '190S-CAL-U32-B". . 1.431. SCS

lii-a.lU'v, III I oiilc iM-t of. south o( track, 1,000 feet southwest of small

lnniM> [Kirth siilr <if Irark, In trlemaph jKile; spike with aluminum

t,i'/ -t;iin].cil l.vj:i- 1,52:1, ;i

lli-.iiil.'v, 17.;1 jiiilo? Cii-t of, [lorlh of railroad, 150 feet caj-t of Rukhonnorlh,

in iiiilc; with ulnminoni lag .'<(am|>cil 1,614. OS

Ui-.iilli'v, IS ;S niiU'f' ™i of, ra.-r of milroad. Ili feel north of stream and r;iilr...,i I""! f.'fi '-.iM "i T.,:xd Urj.lsw' ami small house on west, in

(rl,.-r.i|>li >[iiki- wilh iihiiiiiiiiim lair .lam|)pd 1095" I, 695. 26

llniilii'v. I'll. 7 mill'-. i;i-i nf. '2IH* I'lil wo"! of jmwiT hou.-e at summit of L'iKi tVi'f w'-'t Ml I'loi iiti'il r.iilrcnui, on r'tone; <'hi,eled square

la- >laii.|"'il -Jno" 2,710.45

SI '--Miym. Miulh >iilo nf min.. railroad, .W north of road, -100 feel

liios .-.U.-'J::;!-!!" 2,773.564

fiudlcr we It bIddk blfbviy B mllci. Sail .\rrlii. 11.1 iiiilo.-'si.uthoaHl of. \ie,-t of railroad, in lol|.(,.ra])h [Kile; spike

nillialiiniinuni lauMamp.'.l 517.05

.l..ln„, 'Jl s miles sonthoa-i oi, in liarnyar.1 of Ivd I'ori.T ranc'h, in larjie oak

iivi.; with alumiiiuni ta stamjMl 'W 498. 23

Ji.loo, 20 riiii.w sou!hi'a-l of. imrlh of rortii. in iclcphorio pe.l,- spike wilh

ahLiuii.nni Ulj; '-.J.iO" 5.50. 18

J<'l III!) miles souihoast of. w<-..i of road, iimli-r lar-c oak tm; 1.000 feet

suulh of rani'h houw on eal; imn pwt stampetl '190S-l.'AL-597-U " 596. 97

Primary Leveling. 73

JoloD, 18.9 miles southeast of, of road, 1,000 feet south of white patent

wire gate leading to ranch on west, in telephone pole; spike with alumi- Feet.

num tag stamped *'632" 632. 35

Jolon, 17.2 miles southeast of, east of road, north of white bam at top of

grade, in telephone \x)\e; spike with aluminum tag stamped "742" 742. 32 Jolon, 16.3 miles southeast of, eait of road in angle, in telephone pole;

spike with aluminum tag stamped ' ' 767 " 766. 93

Cape San M Artik 30' Quadrangle.

Point 5 miles north of Jolon along highway south and east to point 9 iniles west of

Bradley.

San Luca.', 14.7 miles south we.-t of, at junction of roads, 0.75 mile west of

"Lockwood;" iron po.t stamped *'1908-CAL-1104-H" 1, 104. 089

San Lucas, 16.2 mile. southwest of, west of road, in telephone pole; spike

with aluminum tag stamped "1014" 1,014. 11

San Lucas, 17.1 miles southwest of, north of road, 500 feet from white house at foot of hill, in telegraph pole; spike with aluminum tag stamped "1023" 1,023.16

Jolon, at east edge of town, in forks of roads, 3 feet east of signpost which reads "Bradley 25 miles-Pleyto 14.5 miles-San Lucas 19.5 miles;" iron post stamped "1908-CAL-959-B" 959. 100

Jolon, 1.9 miles south of, in field 25 feet west of road, in large oak tree;

spike with aluminum tag stamped "924 " 924. 54

Jolon, 4.9 miles southeast of, west of road, 1,000 feet southwest of white

house; iron post stamped " 1908-CAL-949-B " .9. 350

Jolon, 5.9 miles southeast of, east of road, 700 feet south of where road turns due east to "Lockwood,*' in telephone pole; spike with aluminum tag stamped "950" 950.41

Jolon, 6.8 miles southeast of, south of road, 1,000 feet west of where road turns due west, in telephone pole; spike with aluminum tag stamped "969" 968.87

Jolon, 8.1 milas southeast of, west of road, in front of house painted brown,

in telephone pole ; spike with aluminum tag stamped 990 " 990. 2 1

Jolon, 8.9 miles southeast of, north of road, 200 feet north of the Patterson ranch in telephone pole; spike with aluminum tag stamped " 978 " 977. 77

Jolon, 10 miles southeast of, east of road, under large oak tree at edge of

line fence ; iron post stamped " 1908-CAL-945-B " 945. 425

Jolon, 10.9 miles southeast of, east of road, top of grade, in small oak tree;

spike with aluminum tag stamped " 1058 " 1, 057. 80

Jolon, 12.1 miles southeast of, at base of hill on west side of road, in telephone pole; spike with aluminum tag stamped "1008" 1,008. 20

Jolon, 13 miles southeast of, east of road at summit of hill, in automobile

danger signpost ; .spike with aluminum tag stamped 1121" 1, 121. 34

Jolon, 14 miles southeast of, west of road where road angles to east, in base

of telephone polo ; with aluminum tag stamped "971 " 970. 80

Jolon, 14.1 miles southeast of, west of road under small oak tree, 10 feet

west of road; iron post stamped " 1908 -('AL-852-B " 852. 537

Paraiso Springs 30' Qitadranqle.

Oonsales southeast aloni; railroad to point 2.6 miles southeast of San Lnoai.

Gonzalez, 2.1 miles southeast of, east of road, 50 feet southeast of railroad,

in telephone pole; spike with aluminum tag stamped "150 " 149. 76

Gonzales, 2.98 miles of, west of road at railroad crossing, in corner of fence, 20 feet from railroad ; iron post stamped " 1908-CAL-158-B " . . 158. 328

74 SPIUIT LEVEUNfi IK CALIFflBSU. IWlT TO UfW. V

GoiimUw, 4 milM aoiirheBjil <tt. wnsi nf road. 50 irrt iif niltuul. in

phitDo pijp; >piki! with oIuniiDtiin lag utampoil "170" 1

CldDxiilcM, miln* wiiirhoaul of. i.n wi-si nJf -.f nNu), SO fopt fnim militwd,

in telfhrmopuk-; pikcnriTlinlurotnum in V

(.'mnphdra. in mmi of Innrc unnJi! lii ruul, TS feet Dnnhiat of g;niv

h'lunr-; iron iNwtl etampnl "1M8-<'AI.-173-B" in US

I'amplKm, 1 milu ouihRUi nf, nw4 of nod, 00 fm-t r-wl ut nilitKul, in

ijilDphonn pole; * with alnminum tog aUmpiHl "170", ... ii

f'ainphnra, i!,5 milea KUthiiwt nf, cMt nf rosie, 50 [4l tiriin miimod, Jn

ti'lcfAiitiL'pulc; ipikc with alaininuin (aAttunpcd "180" ii

Solrdaii, "t liiwn, in cunuT of ( bMwern nwd aiiJ tBilnnui:

"I9Mt-Itt.vn" ttia

south rvigi. oj ritwn. nl (eoce eonitw, 30 (wt mat nf rKilrand inu-k;

inm HtAQipi'd " 1!I08J;'AH89-B " in. lU

SiiMtul.O.Smik'snuthimstof, atmadrrcMring; lop of rail raarlcRd "ia2".. W.SI SdMiuI, 1. 1 milc 25 feet vmt at miimod, in lolephoDe polv;

Hpike with alum in URi lug sNuDpi'il "1!W" IKi .'il

Sulrdnd. SroUrKiuihcswiof. wmr of railruttd. io t1i!phaiicpnlp; apiko with

aluminum tainamp "2*3" *£i. 03

Sulitlad, 3.0 mile* muthi'iisl of, cast of railroad, 300 luirtli of milvport

147; imn pMt Htampod "IMS-fAlaM-B" an lU

SiilMiid, miles anutbPMt of, ft frri wMt o( track in mvilrh pat. Hpike

wirliftluniinuin Ini; stamim] "207" 207. iB

Suli-iliid, 0 milea aoulhpiut. of. coet of , 300 feet north ol road rriMBirii:,

in tcilognph pole; spike with alumiaom tag tilaipd "211" 210. tH

Sulcdad, 7 mite aautheaat of, east at miboiul, nfr point nf rorre, tni

culvon; fhispU-d i>(|iiare mnrkoi) "lMH" ... 219 '.'6

Srilifliicl, 7.7 milM wiuthi'ji.st nf, cast of railroad, 20 feot south of culvert of

hi)!hway iimlpr raitriKxl, :tOO feet cast of white schoolhouse; iron

Mumped " 190S-( '.\L-2-.M- II "' 22:1. 8:!1

Mi'U. ill Btaliim; rr.ji nf rail marked "239" 2.mK

Jl'-tz, I.I niil('Hi*iutheasl r.(. we?l of railroad, in telegraph pole; spike with

iiliimiiiiim laR Mlampeil "248" 247, j7

-MrlK, 1.7 uiilcpi wHithea.fl of, weBt of railroad; iron poet stamped "1908-

(Al-244-1!" 243 .1

Mi-I7,, ;i miles soiilheasl iit. west nf railroad, near ciir\-e and swiUh, in lele-

uriijiK pist; spike- with aliiminum lag stamped "244" 243. no

Mnt/,. ,).3 mills wiinliea.st nf, e:i!il of 1,000 feet north of milepost

|.-|M; irnd jinM - I!l08-26fl-l(" 259. SSI

, fj.2 miles smilheasl of, east of railroad, 1,000 feet north of milepOHt

\:>'.i, in ti-k'Kraph spike with aluminum lag stamped "263" 26.1. 229

.. T.t melon tmlheast of, east of railroad, 1,000 feet north of miieposi

liiO, in lelenrapU pole; spike with aluminum laR slapped "271' 270. itj

Mi'Iz, S.2mil<'ssnullioiwt of, eaut of railroad at edge of fence, 1,000 feet north

of milepoPt 161; in.n post etampcd "CAL-1908-2Sl-il " 280. H."*

, y.l miles STiuthensI of, east of railroad, 1,000 feet north of milepost

162, in telegraph pole; spike with aluminum tag stamped '297 " 296, IW

-MetK, 10.4 miles wmlheast of. qsM of railroad, in mileposl J63; pike with

aluminum lag stamped "325" 334.63

Kings in front otsladon; top of rail marked "3:17 " a36. 7

Kings City, comer of Broadway and First Street, m cement walk of the

famine'steal hotel; aluminum tablet stamped 'W-Vlf 335.070

Kings t:ilv, amth edge of totm, in corner of line fence west side of railroad,

200 feet south of railroad water tank; iron post stamped 1908-CAL-

Primary Leveling. 75

Kings City, 1 .1 miles southeast of, east of railroad, 1,000 feet south of mile- Feet, post 165, in telegraph pole; spike with aluminum tag stamped "316". . 316. 07

Kings City, 2 miles southeast of, east of railroad, 1,000 feet south of milepost 166, in telegraph pole; spike with aluminum tag stamped "315 "... 314. 81

Kinjjs City, 3 miles southeast of, east of railroad, also sn-itch, 1,000 feet of miles<).t 167; iron post stamped "1908-rAL-321-B" 320. 890

Kin;j:s City, 3.9 miles southeast of, west of railroad, 1,000 feet south of milepost 168, in telegraph pole; spike with aluminum tag stamped "330" ... 335. 70

Kings City, 5 miles southeast of, west of railroad, 1,000 feet south of niilopo.<t 169, in telegraph pole; spike with aluminum tag stamped . . 370. 70

Kings City, 6 miles southeast of, east of railroad, 1,000 feet south of

170, in telegraph pole; spike with aluminum tag stamped "383 " 382. 62

Kings City, 6.9 miles southeast of, west of railroad, 5 feet from same at edge of concrete culvert; iron post stamped "1908-CAI394-B" 393. (JVS

Kings City, 7.8 miles southeast of, east of railroad, in milepost 172; spike with aluminum tag stamped "393" 392. 94

San Ivucas, north edge of town, in fence comer, 40 feet from center of railroad, 200 feet north of road crossing; iron post stamped "1908-('AL- 394-B " 393. 985

San Lucas, in front of station ; top of rail 403. 82

San Lucas, south edge of town, in comer of fence, with red house, 10 feet from center of railroad ; iron poet stamped ' ' 1908-CALr-408-* B " 407. 543

San Lucas, 1.6 miles southeast of, west of railroad, 100 feet south of road croe:4ng, in telegraph pole; spike with aluminum tag stamped "407 "... 407. 300

San Lucas, 2.6 miles southeast of, west of railroad, 100 feet north of block signal, in telegraph pole; spike with aluminum tag stamped "410'* 410. 03

San Lnoai sonthweit alons highway to point 6 miles north of Jolon.

San Lucas, 2.2 miles west of, east of road, north of white bam, in telephone

spike with aluminum tag stamped "375 " 374. 64

San Lucas, 2.9 miles west of, 175 feet west of point where road turns due

west for Jolon, in fence post; spike with aluminum tag stamped "452 " . . 451. 76 San Lucas, 4 miles west of, south of road, in telephone pole; spike with

aluminum tag stamped " 534. 66

San Lucas, 5.3 miles southwest of, in fence comer, 700 feet west of yellow

house on right of road ; iron post stamped ' 1908-CAL-652-B " 652. 236

San Lucas, 6.2 miles west of, north of road, in base of white oak tree; spike

with aluminum tag stamped "689 " 688. 72

San Lucas, 7 miles southwest of, 150 feet south of mud brick house on bank,

in telephone pole; spike with aluminum tag stamped "785 " 784. 70

San Lucas, 8.1 miles west of, north of road, in telephone pole; spike with

aluminum tag stamped "956" 955. 98

San Lucas, 9.3 miles west of, at angle in road, west of road, in telejihone

pole; spike with aluminum tag stamped "1247 " 1. 246. 54

San Lucas, 10.1 miles southwest of, west of road, 35 feet south of telephone*

pole; iron post stamped " 1908-< AL-1434-B " 1. 433. 663

San Lucas, 10.9 miles southwest of, west of road at forks of road, 100 feet

south of summit, in telephone pole; spike with aluminum tag stamped

"1673" 1.673.52

San Lucas, 12.1 miles southwest of, south of road, in telephone pole; spike

with aluminum tag stamped "1418" 1, 418. 36

San Luca, 13.2 miles southwest of, south of road, in telephone pole; spike

with aluminum tag stamped "1237 1, 237. 06

r

(1 city aorckMat lamt Ufbinip id bii taud I tifnti

KLii fliy, I niU" iwrihwst ol. nonh hwd. id mlpptwiBP pulp; (pike with Blumittutn UK "396" ,, SMM

Kiiifp tr- '1 BiilaB ikitUkivI li, of tcnuI, in lelepbciae pol; apUw mlamimira vtuupuil "466 " 4W. M

Kiofpi (Mty, 2,9H inilw norlliruvt of, north of rad, at clump of , no nnrib, in leltrjdioiie pole; spike with ftlumintim tag stamped "im" t&i

KliigK tlty. 4 mUn nortliisaat of, iuOi cd mad, 1.000 fpet easi of iild ham at c'lirvo In nwd. Id UlepboD *: with aluminum lag stamped

KiiiK t'ity, G milM oorttiMat of, m( of mad, 1,000 teet east of white wire gala loKliiiKtu twii hoiic Jn valley; iron inamped ''190S-CAL> 6M-B" i3a

KinKH City, 7.1 milM nl, in foi.' post on audi nde of road, veet of *ununit of range; Bpikt with alumiaum tag stamped 95k tl

KiiignCily, T.lmilpsnorthnulof, northnf mid, atRumroitof range, inteleplianu pole; i-pike with aluniitiuni it auinpt "IMS" I,(H *f.

King* t'ity, S mile* northnut n(, in fence pmt nppaiit gate leading to r<:iad ill valivy at angle in road; pike with akiminuni lag stamped "92S" aST.Tt

Kings City. 9.3 miles norUinwt of, Ht bite of bill. 100 feet from San Loreoin 200 feet iaiit of dam. in fcince post; apiktf with aluminiiia tug iitampd"e07" 896 81

Kings t'ity, 10.3 milM northnaet of, west of San Lorenzo Creek, 5 fe-t from bane (if (.'Otiuuwuod trv, 20 leel bank of (.-reek; iron poet

PolBI O.t mll aouthaul ol SonuiU tcboulfaoux louthaut ijanc coiuty rosd to

whiH.lliiiuse, O.ti mile I'ouiheai'l of. west side of road, in baae of live iiak iree JO inches in diameter; copper nail with aluminum tag sliiiiip-.i "ICfB.M. 14'' U3.3S

SiMiiiiviii whiMilhoue, 1.6 miles southeaat of, SOO feet south of large bain. in liae of live oak tree; copper nail scribed and painted " 135 M. 15" 135.31

Uciiizide.'. 1'. It miles wei-t of, .tO feel wesi of bridge over Salinas River, northinmpoat stamped "110 B 1909 B-1".. 110. L'Sl

lliiiiKiilt's. 2.3 niilcr" v,-vM of, 0.8 mile southeast of, at intellection of road lowest, in Iww of fence post; amliedaud aimed "l((51t. M. 3;" spike. . 164. 81

linii/.alcs, 2.9 miles west by 2.1 mileH wullieasl of. west side of road, at lind. "11 ."iiiiiiiiit of malt ridge, in base of 3IS-inch live oak tree scribed jiiil [laiNH-.l "X I!. M. 4;" spike 206.97

(iipii/.iilcs, 2.9 miles west by 3.3 miles southeast of, west edge of road, at sciiiioi line, ill base of fence post scribed and painted "209 B. M. 5;'' "I'ike 209,12

Ciiiiiiles, 2.U miles west by 4,9 miles southeast of, eaiit edge of road, at section line, southeast comer of field, in base of 30-inch oak tree scribed and iniiuied ';i22 It. M. 6;" copper nail 321. 72

tMitiniiU's. 2.9 miles west by 6.9 miles southeast of, west edge of road, 0,4 mile north of jnnction of road to in base of fence post bribed and pnintiKl ''iSO 1(, .M. 7;" spike 2SC, 09

Snlimuis .alHM.house, in sciuthcast corner of school yard, at junction of road to (amphora; iron post siamiied "211 1909 B B-2" 211.886

Primary Leveling. 77

Subranis schoolhouse, 1.1 miles southeast of, south side of road, in base of Feet. 40-inch oak tree scribed and painted " 159 B. M. 8:*' copper nail 156. f6

Subranis schoolhouse, 1.9 miles southeast of, east edge of road, north end of gate to second-class road through Spreckles Sugar Co.'s ranch, in base of gatepost scribed and painted B. M. 9;'* spike 215.28

Subranis schoolhouse, 2.8 miles southeast of, at J. Whisman's ranch, 5 feet cant of mail box, in base of fence post; spike with aluminum tag stamped ''194B. M. 23*' 191.88

Mission schoolhouse, 0.3 mile northwest of, southwest comer of field, at intersection of road to east; iron post stamped "238 B 1009 B-7*' 235. 091

Mis.si()n schoolhouse, 1.3 miles southeast of, east edge of road, at lane to eai?t, in base of gatepost; spike with aluminum tag stamped "210 n. M. 24 " 207. 17

Soledad Bonth np Arroyo Seco Creek to a point 4 miles southwest of Oreenlleld, thence

northeast via Oreenlleld to If eti.

Soledad. 1 mile south of, 50 feet north of bridge over Salinas River, in base

of telegraph pole 3086; spike with aluminum tag stamped " 196 B. M. 35 " 195. 50

Soledad, 1.7 miles south of, at intersection of King City and Paraiso Hot Spring roads, in base of telegraph pole; spike with aluminum tag stamped "196B. M. 36" f 195.30

Soledad, 2.9 miles south of, 0.5 mile south of bridge over Arroyo Seco Creek, at intersection of road; iron poet stamped " 185 B 1909 B-12" 184. 744

Soledad, 4.8 miles south of, northwest comer of bridge over canal, in floor; copper nail with aluminum tag stamped " 203 B. M. 37 '' 203. 30

Soledad, 6.2 miles south of, west edge of road, 250 feet north of grove of trees, at cross fence, in base of fence post; spike with aluminum tag stamped "315B. M. 38" 316.21

Soledad, 6.8 miles south of, 25 fet east of intersection of road to west, 0.3 mile south of white bam; iron poet stamped "375 B 1909 B-13" 375. 128

Soledad, 7.7 miles south of, east edge of road, at second-clafs road, in base of gatepost; spike with aluminum tag stamped " 396 B. M. 39" 395. 80

Soledad, 8.8 miles south of, 0.2 mile north of point where road bends southwest, in base of telephone pole; spike with aluminum tag stamped "378 B. M. 40" 377. 93

Greenfield, 4.3 miles west of, on section line, 1 mile north of Arroyo Seco (Vcok; iron post stamped "376 B 1909 B-14" 376.160

Greenfield, 2.3 miles southwest of, southeast comer of field, 15 feet south

of irrigation canal; iron post stamped "329 B 1909 B-15" 329. 512

Greenfield, 1.7 miles southwest of, southeast comer of field, 300 feet south of house, 700 feet south of crossroad, in base of fence poet; spike with aluminum tag stamped "313 B. M. 42" 312.24

Greenfield, 0.6 mile northwest of, at interse<:!tion of road, in base of telephone pole 3322; spike with aluminum tag stamped " 277 B. M. 43 " 276. 07

Greenfield schoolhouse, at large gate to school yard; iron post stamped

"286B 1909 B-16" 285.865

Greenfield, southeast end of town, at crossroad, south end of concrete culvert over irrigation ditch; aluminum tablet stamped "287 B 1909 B-11" 286.804

Greenfield, 2 miles northeast of, north edge of road, at second class road to ranch, in base of fence post ; spike with aluminum tag stamped " 246 B. M. 34" 248. 73

Greenfield, 0. 9 mile northeast of, east side of road, opposite windmill, in base of fence post; spike with aluminum tag stamped "244 B. M. 33". . 243. 84

Ae itoMa m ififiH -USD. U " ,tt2 SB

Bit. M braiiirfiM rf wt bM ttamftd -MO B IIM B-B "- - . 3a Uf

pOaSai; tpifa wilfc fciwtoilB ttg "gl B. M. CI-?

DbVi Cky Biii M wfai — of. adia of kmmI. In bw. o(

pJ31: ifilto vUalnimH taKrtmfMd B. U. 27". Xir GO Eav Olr BriApc S aankmit of. vm ade* nd. vbara raMcl

tWM HM WMV Waft a Imc Mnk lApfcuai |Mb 3CM; trna |km

Mil II I 'a B Mat B-*" .- 338. a

plnMpalSaB;UwitbaluntttiraibalMnped-2S2B. M. 8g" 2&W

Ktn0C1tr DridscS-SmkvMnbwMotntmtoaf nd, inlMaenf tcl-

pbocwpijkSSaS;MlwilbaliinBBnBtacdUaped'*3MB. U.29" -OLUi

Kln;9 ('Itj: Itridsr. S.t mifa BMtkweM iSJ! nBes ooalbMBt o[ GreenfieLl.

b <il telepbme (mIb 3SA>, on line between Imra umI wiDdniill;

gmaBriJ. I mUe mmihmtt uf, in bwe d iJplwne [ioleL338B: ike wilh

danoBOT tif tftMapod '"Sn B.it.SX" 2GS.ST"

Lioiiuilcw, I n mil 'if, it iatetnerlifia nf n.ed \-j naat, in Infe of

Ickphuae pale: ipifcoiUi aluminum tag lUmped "IJ B. M. 15" 113. 38

(iiinrilim. 7 milm nt hy mart, mat baakufoldiTrM'kbed, 0.5 mila south

.il<;|..ria wh.->rhr,u: irf-n T"-.l -lampftl "Sir, H 1009 BS" .>I!.S3S

Gluri.i H hoplh'n:-!-. IM miles iwulh i>[, where road jags ea?t, opposite houae ill ltipvi' 'pf tree?, in ba,-* nf 2|.iiirh pine tree; spike ?cribed and ]i:iiiii-(l :!"i K. .M. lit' 395.80

Gl'>ria .xln I'll bn ;( miles MHirh.'j-' nf. iiorthc.nt romer of field, 600 feet .-.i-t nf l.jni, wlifri' riiad Iiinis m .-niidi; iron imsl tamped "338 B 1909

li-fi"' 338.458

Camptaora louUiviitl to Subruili tcboDlbonM.

('aniphc.r.i. IM mill's Mjuihwol of, e-asi (d(,'e iit riiaii. north bank of river, in

1i:lh' ip[ f<-ni I- i-])ik<,' H-iih iiliiniiniim laj; clamped "147 B. M. 45" ..

( 2 7 i?iili- Minihwc'sl iif, IIX) fi-et north of bend of road, opposite .-iinill )iiii;.-i', ill ui cMtrniiivinid Inc; iiike nilh aluminum tag .-ti, in Jill I -Itl li, M. li;' 140.95

(ii.ii/ili-, OM niili' ttosi of, north end of bridge over canal, in floor; copper

iiiil ]>;u:ilc.<l -Jl'H H. M. 1" 12T.6T

2. 1 iiiilef went of, intersection ol road to south, in bat ot

fiMii'i piHt HiTilicd .Hid '121 It. M. 2; " spike 124.06

PSEEST VALLEY 30' QUADKANaLE.

S.fl mUai tontbtastol Ban Lncu louthcait aloDg rallioad to points mli( lODth-

Mt ot San Ardo.

Sun l.iniip, 4,l> miles southeast of, wfM Tiilroiul, in telegraph pole; spike

iili iiliiiniiium tnENtrtniped ";t',l7" 396.26

Sun l.iiiav. .-, li mill's siinthi-.i.-'t of, ciist of (rark, (eel of dc--

buihlinij, ill li'lfKroph iHile; pike with aluiniiium tu'slani|>ed ''408".. . 406.56

Primary Leveling. 79

San Lucas, 6.6 miles southeast of, wet of railroad, 100 feet south of road Feot crossing; iron poststamped "1908-<.'AL-429-B" 427.722

San Lucas, 7.5 miles southca:t of, west of railroad, 100 feet north of block si;jnal 1805, in telraph pole; spike with aluminum tag stamped "403 ". 401. 75

San Lucas, 8.6 miles southeast of, west of railroad, in telegraph pole; spike

with aluminum tag stamped "419" 417.39

San Ardo, in front of station; top of rail marked *'458 ' 457. 0

San Ardo, 0.1 mile southeast of, east of railroad, 1,000 feet south of water tank, in base of target 1833; aluminum tablet stamped "1908 CAL- 459-B " 457. 718

San Ardo, 1.3 miles southeast of, east of railroad, in telraph pole; spike

with aluminum tag stamped "445 " 443. 495

San Ardo, 2.3 miles southeast of, east of railroad, in telegraph pole; spike

with aluminum tag stamped "445" 443.97

San Ardo, 3.1 miles southeast of, east of track, in culvert under railroad corner; aluminum tablet stamped "466-B" 465. 191

From point 10 miles northeast of Kings City along highway east to Loanoak, then* southeast via Priest Valley to Cramp's ranch, thenoo northeast 8.7 miles.

Kings City, 12.7 miles southeast of, south of road, at ranch house, in gate post leading to straw yard; spike with aluminum tag stamped "820 "... 820. 05

Loanoak, 0.8 mile east of, north of road, in telegraph pole; spike with aluminum tag stamped " 925 " 924. 79

Loanoak, 1.6 miles southeast of, south of road, 500 feet west of Andrew Hopkins*s residence, 400 feet west of where road crosses creek, in telephone pole; spike with aluminum tag stamped "945" 944.67

Loanoak, 2.3 miles southeast of, southeast comer of road intersection, 800 feet north of schoolhouse ; iron poet stamped " 1908-CAL-1027 " 1 , 027. 138

Kings City, 17.1 miles southeast of, north of road, west of Pet Bengard's ranch dwelling, 5 feet south of creek, in telephone pole; spike with aluminum tag stamped "1029" 1,028.74

Kings City, 18.5 miles southeast of, south bank of Lewis Creek, 500 feet west of Pet Bcngard's ranch house, in telegraph pole; spike with aluminum tag stamped "1107 " 1, 107. 30

Kings City, 20.97 miles southeast of, north of road, on bank of Lewis Creek, 25 feet north of where road crosses creek, 500 feet north of Ernest Bengard's residence, in telephone pole; spike with aluminum tag stamped 1300 " 1 , 299. 66

Loanoak, 9.4 miles southeast of Kings City, 22.8 miles southeast of, cast of road, on fence line of the C. O. T. Co.*s pump station No. 4; iron post stamped "190H-CAL-1404-B" 1,404.467

Kings City, 23.6 miles southeast of, south of road, 500 feet east of Miller & Lux goat ranch, 25 feet south of Lewis Creek, at angle in road, in telephone pole; spike with aluminum tag stamped " 1455 " 1, 454. 57

Kings City, 24.7 miles southeast of, 100 feet north of where nmd crosses creek, in leaning rottonwood tree; spike with aluminum tag stamped "1518" 1,517.65

Kings City, 25.6 miles southea-st of, north of road, 10 feet south of Lewis Creek, 600 feet south of schoolhouse, in telephone pole; spike with aluminum tag stamjMjd "1580" 1,579.92

Kings City, 26.8 miles southeast of, on south side of road, 50 feet north of Lewis Creek, 200 wcit of where niad creek, in large pine tree; spike with aluminum tag stamped " 1669 " 1, 669. 04

BD MflltlT l.bVEU.NC; IS (-ALIKOBKU, 190T TO lUlU.

City, 37 .7 milm iwuthi-nrt nl. Brmiw in Sm Bcnilo Cftiiuly, on JamM It<>ninTil'ii ranch, Hi fiHrt, ol in pile; aptkn Willi hIu mill II til lai BiHiiipwl ir2&" t, TM.Q

bauuiuk, 1.%, miln iuutliniet of, an Bonganl nuxb, in banc of reeidvoc* tiyatdootteni, 30 tcvtnonhot barnyard le; iiuo nUmpril "IDOB- CAI,-i78e" l,TEi-<

HMigQitl ronrh, IflO i-biA of, north of ntA, in tlephun' pult; spik* with Aiuminuiu laKH "1843'' 1,M£JI

lit'nic''il , i.A milfs cvBt f, of road, IHO (cM. Mat gt rwul .niw'OB Ciwk ond big cut. iu leaiUng cotlonirood Uw; Bpiki- wiihuluminuin Uk "IflM" 1.M4.ar.

BpfiRiLnl mni-h. ill mili mua of, of road, M tmt nonh of in ruad, 150 ti-ot north of LuwIb Croek, iii loU'iphone pole; spike with aluminum "198S" l.W'.ll

Dourd , 5.1 niilM xouthmst u(, euulh of ruad, 1.000 fuct smith of whil nuiL'h houat, 100 Cct north nf Lewi Creek, where nwd crMtm rronk; imn post stamped "l!)0S-CA1219f' 2,197.11

IltMieard rauch, 6.2 milee soutbtwit of, north of road, 500 foet south of (iril6a rwidrncc, in tclepbonc ; spike irilli aluminum Uiti oliknipinl

llpnird much, 7,4 miles eoutbi-net of, north of rosd, 0.5 mile soiirhcaet of Palmer BriM.'store, in tokphonopole; irpike with aluminum tng stamped "2327-* l,327.i

BeTi;;ard ranch, 8.1 milei soutbesAt of, nonh of road, 200 of le leading to ranch with white house, in telephone pole; spike with atuniinum tag atunped "2372 2,372.lt

Beurd ranch, 9.5 mtlMMUIheaat of, SOOftwt north of Matin's Iioubb. iii li> pole: .jiikr with alumiiiiim tajr "J!H)*' 2, 490 3B

niiicli, mili-s sciiuhcusi of, M feel nonh of road on summit of ilivuic. in liiiHC of hirgi- imk trci': with aluminum tag Mamped

IlciiLpiril r.inrh. 11, :( mill's wiulhcii.-'l of, north of road under large cotton- H-rn.a ircc: inuL "lIHIS-l Al '0o7" 2,057.142

"Icnwird 12.1 mill's ,;<uilli.-.it ..[, north of road, 0.8 mile north of ('. 0. T. Oil 'o,'s pumpiiLs: elarion, in piiip Ircc; spike wilh aluminum

tiff.-liimpcd "lOHH" l,96-'*.27

'. O. T, Oil I'll.' s utiitiiiu, 0.2.'i mile soiilheaft of, in telephone ]>iilcon uiirili li;iiikof cri'i'k, fed north of nail; s-pike with aluminum

t:ig stumped -JSli;!" 1,863.41

O. T, Oil ('...s station, 1 mile of, north of road, iu

ti'lephone pole; s].iki' with iiluminNm tag .-tiiniped 1,794.08

'. O. T. Oil Co.'i- iiumjiinc sliition, 2.2 miles southeast of, iioHh of 20 feel north of ircck, in cetlonwond tree; spike ivith aluminum lag

stamped "Ulsr' 1, 881.01

', O. T. Oil Co.'s pumiiinsr stutiou, 2.li miles snullieast of, south of road under tree, :W0 fei't west of where road crosses cn.'ek: iron

stamped "lllOa-'AI.-Kilil-B" 1.660. S8

O. T. Oil Co.'s pumping staliou, 3.!1C mih-s east of, north of road, 100 feel west of gulch, iu telephone pole; spike with ahiminum tag

"Ifiai " 1,603.41

'. O, T. Oil Co.'s pumping stuliori, 4.7 miles ciisl of. north of rail. 50 feel north of cn'ek where pipe lino cros'srs 'feck, in telephone pole; spike

Pbimaby Leveling. 81

C. O. T. Oil Cx>.'8 pumping Htation, 5.9 miles east of, north of road, 100 feet Houth of Bennett's ranch house, in telephone pole; spike with alumi- Feet, num Ug stamped " 1458" 1, 457. 60

Crump's ranch, east of nmd , under oak tree, 25 feet east of entrance to dwellings; iron post stamped "HGO-B'* 1,459.899

Crump's ranch, 0.8 mile east of, at forks of road, near sign post " tesno Hot Springs" in base of pole; spike with aluminum tag stamped ' 1448 " 1, 448. 02

Crump's ranr'h, 1 .5 miles east of, northeast of road at angle to small gulch,

in telephone? pole; spike with aluminum tag stamped 1544 " 1, 543. 77

Crump's ranch, 3.7 miles east of, north of road, 500 feet west of creek, in

telephone pole; spike with aluminum tag stamped **1103" 1,163.31

Coalinga and Panoche 30 quadrangles; Tracy 16 quadrangle; Copperopolis, Crows Landing, Holt, Ingomar, Los Banos, Newman, Peters, Stockton, Volta, and Westley ly quadrangles.

Fresno, .Hkkced, San Joaquin, And Stanislais Counties.

The elevations in this Hst are based on the results of precise leveling along the Soutliern Pacific Ilailroad in Bulletin 342, to which bulletin reference should be made for additional elevations in this area.

Leveling in all the quadrangles of this list except the Copperopolis, Holt, and Peters quadrangles was done in 1908 by W. 11. Monahan. Additional work was done in the Coalinga quadrangle in 1903 by W. V. Hardy, in 1907 by J. W. Muller, and in 1908 by L. F. Biggs; in the Stockton, Copperopolis, and Peters quadrangles in 1896 by J. B. Lippincott, and in the Holt and Stockton ({uadrangles in 1907 by B. A. Jenkins. The State cooperated in the work of 1907 in the Stockton quadrangle and in all work done in 1908.

COALIHQA 80' QITADRANQLE. Bench mark 4 mlleB wert of Lethent west alone Sonthem Padflc Railroad to Alcalde.

1.3 niiloH northcust of, 50 iooi poiitli of track, 3 fcMt eawt of telegraph Feet.

inilepoKt UTO: iron post stamped " Mm (i " :I06. 166

Huron, 2.5 feet south of entrance; iron post Htam{)ed "380 G". 380. 231 Arroya PoHii Jheiui, I mile southwest of, 50 feet south of track, 3 feet east

of telejuaph mile pole 285; iron post stamped 455 (i " 455. 147

Ora, 4 miles east of, 50 feet south of track, 8 feet north of wagon road, 5 feet

of telegraph mile pole 290; iron post stamped " 569 (t" 569. 216

Ora, 2.1 miles east of, 50 fcHt south of track, 5 feet east of telegraph mile pole

292; iron post sUimpfKl "(iOOG" 606.101

Ora, 2.5 feet wet of telegraph marked with name of station, south of

oil tanks, 50 f<?et south of tracks, 2 feet north of wire fence; iron post.

stamped 647 G " 647. 187

Coalinga, southwest end of station; iron stamped "671 G*'. (This

bench mark has been moved, but its elevation is not materially changed). 671. 152 Coalinga, 1.7 miles southwest of, in mouth of Waltham Canyon, 800 feet

north of ranch house, 50 feet south of track, 10 feet northwest of road

junction; iron post stamped "716G" 716. 110

Alcalde, 70 feet north of station, between station signboard poets; iron post

stamiKHl " 852 G " 852.214

95094*— Bull. 481—11 6

HPIRIT LKVEUSf. IS CAUFOUXIA, IW, TO mO.

OklUocBU TImTIH on Co.-*

IViBliiiin. wHBtuI, 20 Ilii mat of rnuii. ISOfn't nnubnuant nutitliwm

im"

CmliKim, & mile* naftbwtM of. 1 tnilo north of AMociatii Otl i.V>.'a punip 30 rmttiul of Motion omier, 10 eiMl of nd: Eitrn pcMauunpMl 2. 190TIJ' sam

Caaiiapi. 7 A mini norlliwiwl I.IIUU tvn nunh of big t;tiik bnuM where TuudcrtrnMauuiniit. 40 (ijrt *iurt of rwd; irtni pmtiiX*mpM" 1.244 No 3. IBOTG'' - 1,S44

Clinfm, ti fniltM north ot, on Oil Clly kmuI, M leet wtei of drain, 10 fiwt <iotitUwBi III junction of raada: imu iifaunpiKl "I,lfi7 No 4 l.l67,Si

I'oaliu, 12 inilw iiufth of. 400 fiwt Kiuth California Oil I'u 's iffitv, XttO fivt nf big inurhinp shop*, 1 0 aouih of ruad . 'i fn-t last relics (III w'ction lino b<-lweeii wxs. 21 aud 32. T. 19 S., II. 15 K [run [ii]([titUim)>wl " 1,467 Nu. 6. 1007 G" 1,4S!I

Ciulin. iO.b mtlra iionhaat iif, mt teat Itiie >ii jirciperty of Suuidun] Oil Co. tind Cikiiforuia Liiniud Oil Co., on unrth itod aaaxh liiip. auuth nid of fenrp, top of imn fence port 0 inch in diameter. 4 fwt liijrh; |ntuld poinl; por jMlnted "H.S.B.M. 973"; tluminutn lA "973" t*i.'lil oil ]>uBibnio 973,12

CiMlingn. 9 milw northmiit ol. 400 fwt ol Suudud Oil i'n.'n puni|) pUnt Nu, 1. 100 feet wiutliwust uf Wgc block nil twik, M fc*t mudiirat

ol junction of mtda; innipa4Nunpod"MNo.01W7O".. >B&S|£

CouUiiini. 8.5 northeast of, on road to Stundud OH Co.'b piimp plant

Nu. I f.'.-l Huiilh uf juiKliuii ..f four .i, feet -rat of Coaliiiira an.l l''riwioBiviil>(Hifd: iron pi*l (iUim|"'d "sioKo, 7, l'.t07(:" 2HI

'iiicliiitoi. mira iiortlipaal of. on roHd lu Standard Oil Ctr.'a punip plant -Nil. I, jofcpl wpBlofrortd: 8, 1907 G" 718.470

Oni. 100 Niiiiili of Ntalion. 50 (pet south of Southern Pacific Railroad truck. 4INI feel wiiilh <if Suutiiem Piieific Co. 'a big oil tanks, on W. V. ILirdy'slevolliiie: 647.187

JoDai raneb norttawtit ta CoaUncL

raiu-li. .'iOO foptwentivf lioiiw, at fence eonior; iron poet etftiuped " 1062

1008 50 H"

KrHtihnKOii'.t r.iiivh, 1.9 niilea northwest of, 15 feet eaat of road; iron post Htainited -HIT H 1908 51 B' 1. UK 466

KrunhafreirB ranch, 4 milea northwest of, 0.8 mile ireetof L. Kranhngen 'a house, 30 feet south of section eonier at road junction; iron poet slapped H 53 It 1908" 91,'2. 327

I.. Kranliueen s house, 0,9 mile nonhwet of. 500 feet ent of eehoolhoiise. Vl feel couth of creek, south of road; iron poatstnniped -806 B 1!08 R 53". m5. 665

,\h in r.inch. 0,4 mile northwest of house, 25 feet south of junction of roads; iron |)ost stamped "672 B1908" 671.558

('onlingn. 5.5 miles southeast of. 20 feet east of road, 25 feet northeast of wash. 350 feet north of cabin, at junction of road: iron post stamped " 737 B 1908 B 55" 736. 516

Caalinga, 3,5 miles southeast of. at junction nf roads, 0.5 mile simla of ranch hoiiM..; iron post stamped "fH7 1908 B 56" 646,322

Primary Leveling. 83

Point Abnt i milei wit of Alcalde to Coalliifa, theoM eait and north to point abont

IS mitoi fontheast of Hayes.

Crump's ranch, 5.2 miles east of, south of road, 50 feet south of Lewis Creek, Feet in Warthan Canyon; iron post stamped "1076 B 1908 CAL" ! . 1, 076. 003

Coalinga, 1.7 miles southwest of, in mouth of Warthan canyon, 800 feet north of ranch house, 50 feet south of track, 10 feet northwest of road junction; iron pont "716 G" 716. 110

Coaling, in front of atat ion ; top of rail 669. 8

Ora, 2.5 feet west of telejtiph pole marked with name of station, south of oil tanks, 50 feet south of track, 2 feet north of wire fence; iron post stampiHl " 647 " 647. 187

Ora, 2.1 miles east of, 50 feet south of track, 5 feet east of telegraph mile

iron "606 G" 003

Ora, 4 miles east of, 50 feet south of track, 8 feit north of wagon road, 5 imi

east of telegraph milepost 290; iron post stamped "569 G " 569. 202

Ora, 8 miles northeast of, 20 feet west of wagon road, opposite small canyon

on right; iron post stampofl "648 B 1908 CAL" ()48. 448

Coalinga, 9 miles northeast of , 400 feet west of Standard Oil Co.'s pump plant No. 1, 100 feet southwest of a large black oil tank, 30 feet southwest of junction of iron post stamped "806 G 1007 No. 6 " 806. 253

Standard Oil Co. pumping station, 2.8 miles north of, 25 feet east of wagon road, on side of hill; iron post stamped "653 CAL 1908 B " 653. 276

T. 19 N., R. 16 E., sec. 2, 10 feet west of wagon road, 250 feet south of the

Imperial Co.'s pumping plant; iron poet stamped. "635 CAL 1908 G ". . 634. 997

Imperial Oil (.'o.'s pumping station, 4.1 miles north of, at foothill of range, and 10 feet south of wagon road; iron post stamped "503 CAL 1908 G". 502. 692

Im])erial Oil Co.'s pumping station, 6.4 miles north of, on line fence, 785 feet southwest comer of Ladd's ranch; iron post stamped "504 CAL 1908 G" 503.941

Ladd's ranch, 3.5 miles northwest of, 1.5 miles northwest of clump of Cottonwood trees, opposite large canyon on left; iron post stamped "480 CAL 1908 G" 479. IKM)

Ladd's ranch, 8 miles northwest of, 2,798 feet south of gulch, leading from canyon; iron post 8tam[)ed "553 CAL 1908 G " 553. 260

Ladd's ranch, 11.9 miles northwest of, south edge comer of new barn at bas( of foothills, on a small plateau, 100 feet north of ravine; iron post .stamiHKl "578 (A L 1908 G " 577. Um

Crump's ranch south to Stone Canyon.

Stone Canyon, 7.5 niihs northeast of, 1,000 foct northeast of G. E. Frame's ranch house, in large oak tree on west side of road; spike with aluminum tag stamped " 1341 " 1 , 341. 05

Stone Canyon, 5.8 miles east of, on top of inoimtain 700 feet east of large

canyon, on north side of road; iron post stamped "1908-CV1>-1699-B ".. 1, 699. 199

Stone Canyon, 4 miles liast of, south of road, on top of knoll where road turns to left, in base of small (ak tno; spike with ahmiinum tag stamped "2593 " 2, 593. 33

Stone Canyon, 3 miles east of, 5 feet north of road where leaves underenters open, in base of small oak tree; spike with aluminum tag stamped "3173" 3, 173.07

Stone Canyon, 1.3 miles east of, 10 feet north of road, exist of gulch, in base

of laiige oak tne; spike \*'ith aluminum tag stamped "2883 " 2, 882. 72

WIBIT LEVKLl.N.i rs TAUl-niiMA, l-.m; T"' l; PAHOCXX m- aVADILAKOLZ. il 11 onUwMI of H*rH to JuBlMB naok. ftbaitt ( mitt xnitkvnt'vt

, 14.11 miloH i.i(, 60 loot oust uf creek, IQ feet eBt xf rmul latMliDK f'"" Cantua to CbeDiuiy nncli; irnn poet atAmpeil

T, 15 8,, R. ic. 35; irun post eWmped "492 C'AL

1808 a" J9L7I

lAdd'tmuich, SO.l mi Im north vMl of, botveen waguu lusd uid , lOO [net ut point wh(>rfi nwil irunwe cm-k; iron post "555 I'Al, liKMl G" - US.n

Ladil's , 23,2 miles uorthwwA uf, WMt ul row] leading niirtb fmm CuotUM CiMik (u Clioiucy iwirh, 100 font soutli at point wluiM rti] I'rtMM nvinoi ifnn pnatUmped "ftM CAI, 1908 O" SBS-Vt

limytm, on run) letidfug uul Krumo to mouth. n( big PaniKrlio mnycm, M fcM north of lUyMistnrc, 60 fwt south of road, undrnnl um ; ir.iB iH*l (rtAmpwi "5ta CAI. 1908 G" 502.M

Ukj'ca, 3.9 miliHt northwiMt iif, ham nf fnothilU, 1 tuile east uf Urgo ranynn and 0,5 mile Eniith of Urc rnnJo; Iron post stamped "Ulli CAI,

llnyra, 7 mira of, tO (wt wort of leaders aorthwost trim lUyeatA Avery raoti iron pust stamped "629 C'AL 1908 G"

Littk' I'ui'>rhe -k, ii> feet north nl niirth butk, I S ioJIm northtust uf Avery ranch; iMn puM KUmpttd "407 CAL IBOtt G" 4M.m

LillU Fauuche , S.4 aiiluti uurtJiwiidt of, 10 fiMt weot of iron tukI iHadinf; north fmm Avory dutch, bam of lOothilk; tna port eUUnptn] ':tS4 V.\t. VMKI C," 383,

LiMlf PaiiiK'hi' fr.-fk, (i.-l niilfs iintihiiTst c.f. If, Rpi, w.-,sI of a-i.,i py,l, foci Bi'utb lit old (Icaerlcd building, O.ij mile (Hut uf fixithilLi; irun Plainpiil —Ml CAI, lOOa G" 34a 7H

Lililc Pan<)('h(- Cn'k, 10 miles norlhwi of, at forks of road, 75 feel of San Juaijuiii & Kinj;s liivcr Canal and irrijiticin company's projected caiiHl; inn |.MSt fHiimpcil CAI, liHli* (i" 149.940

IITOOMAR, LOS BANGS. AITD VOLTA T'/ atTADRAITOLSS.

SntUUit WBit to Boptlan. Uince loatli to AnutsnluB.

Sni'flint:, 4.5 niiloH tKiuthwevI uf, uonitir of fork wilh road Id north, at

fcdcei-onierof J.t.;, Kiuidle'f ranch; iron pmt stamped "204 B" 204.087

at BOUtheaal corner of fork with private road, in front of saloon;

inui postBtampi'd 'IS-i I! " 134. 98S

Uopeton, 2.2 miles sonth of, (luithwwt end of bridge over Merced River,

west margin of road; iron ]ni!'t "172 H" 172.245

AiiiKlenlam, 140 fiil w.vt r.f Urn,- ivurfhonw, 10 feet eawl ut station sign-

l.iiard, -Jll feet nirlli of 1nii-k: inm "215 it" 215.156

Point &bonI S nil*! lanUiinat a( Lna Banoi i DOTthvut onc SouUiHn FiMNo ItkUroad n 1.1 mllai BOith of QDitta*.

I'onuT of yard, at junction of

111. pill- lejdiiiK I" dwelling and 10

,io of nd; iron imwi suimped "117 C.Vl

eh

r.n

'h. ItHl f.

lor Ih

.feudal.

Primahy Leveling. 85

LoH Bano8, 2.8 miloB north of, east of railroad between road and railroad, on fence line, 150 feet east of 138; iron post stamped CAL Feet. 1909 G " 114. 096

Volta, in front of station; top of rail marked " 104 " 103. 9

Volta, north end of town, 500 feet northeast of schoolhouse and 25 feet west of track, at base of telegraph milepost 136; iron post stamped CAL 1909 G " lOL 850

Volta, 4.2 miles north of, 25 feet west of railroad, at base of teUgraph milepost 132; iron pont stamped "93 ('AL 1909 G " 92. 397

Ingomar, 0.2 mile north of, at base of telegraph milepost 130, 25 feet west of

railroad iron post stamped ''91 ('AL 1909 G" 90. 486

Ingomar, 4.2 miles north of, at base of telegraph milepost 126, 25 feet west of railroad; iron post stamped "96 CAL 1909 G" 96. 049

Giistine, in front of station; top of rail marked "101 " 99. 95

Gustine, 1.4 miles north of, 5 leet east of milepost 123, 25 feet west of

railnxid ; iron "94 " 94. 181

Crows Landing And Newman 7H' Quadrangles.

Point 1.4 miles north of Gustine along Southern Pacific Railroad via Newman and

Crows Landing to Emerald.

Newman, Hoiilh end of station, 10 feet west of , 5 feet east of telegraph

pole; iron post stam|>ed "88 CAL 1909 G " 87. 827

Newman, in of station; top of rail marked "89 88. 4

Newman, 4.4 miles north of, 5 feet north of telegraph milepost 116, 25

feet east of track; inm post stamped "104 CAL 1909 G " laS. 644

Landing, 125 feet east of station, 300 feet south of telegraph mile-

1 14 ; iron post stamped " 111 CA L 1909 G " 111. 185

Oowrt Landing, in front of station; top of rail marked "111 " 112. 6

CrowH Landing, 3 miles north of, 10 feet north of telegraph milepost 111,

25 feet east of track; iron stamped "114 CAL 1909 G" 113.351

in front of Btaticm, toj) of rail marked "103 " 102. 8

Emerald, 25 east of track, 5 feet north of telegraph pole, with sign

reading "Kmerald;" iron post stamped "102 (AL 1909 G" 10L940

Copperopolis, Holt, Peters, Stockton, Tracy, And Westlet Va'

Quadrangles.

At Stockton.

SttM'kton, southwest corner of Scott Avenue (south side of M()rmon Channel) and enter Stn*et, on north iron west end of Cool Corner saloon; "Cool Corner", bench mark 15. 633

sout4iW(>st corner of Scott Avenue and Center Street, 18 feet from

curb corner and 12 feet north of iron doorsill; iron post stamped "16"... 15.973

StiK'kton, at southeast head of channel, comer of Weber Avenue and Eldorado Street, east of steps at corner post; inm plate 12. 714

on top of Htone post on north side of courthouse and west side of walk 16. 1

Stot'kton, San Joacpiin courthouse, in angle of wall at north entrance, west of door and c<)lumns, north and first window west of it; bronze tablet stamped " 18 " 17. 953

Stockton, Southern Pacific Railroad paswnger station, Milton and Oakland branch; top of rail 18.7

Stockton northeast alone Milton road and Sonthem Padflo RaUroad to Petara.

J. B. Marsh's house, at northeast comer of entrance to iron poet stamped "34" 33.606

w

SriHIT LRVEIJNO IN CALIFdBMA. I'liT !.' li'Iil. Iwntd Boitbwnt ktama Beothcn Paalfic KallmMl to Tracy.

Emtnld. 3 'i luiJiw tun-ih itHi iit iravk. o iirt nf nulpot i

105; inm poBt 8impl lUCAI. 1909 no.Wt

Wiwfli'}', 200 twt i'*M o(, front nl sutioni mm poet stunted "8S CAl.

laOBO" W.M

Wmtlcy, 3.3 milw itntth at, gS net of track, 5 (eel Buuth of laitopatit Wt;

iniB port Mamped "86 CAl, 1909 G" 8a.S6D

\\'iw[|c>)', e.3 milvH ucirtli <if, 25 mmI itf Irark, 5 feet oouth of

milppiwilIB, iron iwm nKwnpwi 'MOOt'AI, 190G" 99.NI

W'mllfy. 9.3 niili north nf, 35 feet aut of track, ID north of lelcKnpfa

WeslJcy, 12,3 mtlM onrih 21> leet est of Intik, 10 li-ui #uuth of telegraph

mili')Hl 89; irn punt Biotn pod 'TSt'AL 1909 G" ;tM

Wmiley, 15,3 nl, at Snuthom Pacific and n'stem

iWific Itoiiway cmHriiiK; topcif rnil ntarknd "78" , 77,81

Wwllpy, 16.3 milee north of, "B feel ca of Southern PBdfic Railmiul, 100

fif 1 iiurib of Western Pa'-ific Rilwiiy iTuminj;, 10 feet amtlh nl mile-

poul Hfl; iron port stamped "78 CAl. 1909 G" KOtt

Tmcy, 18 reel north of niiiepiwl 72; iMii stamped "53 927 It" fiBLfl

(Thifl heiieh was iinil u new .me prppted l.y ninKP, 1910.)

BtaoktoB wut aloac AtcUion, Topaka A Saala Ballwar to Till nHleh.

Siii(-kt.iii. ill truntof Wslion; top iJ mirth mil 17.8

.Slocktmi. A.8 milee west of, 300 feot ewt iif milepoat 1127 where level jfiins

nkilroid embankment, on levee at fence comer; iron pool camped "1B07