Geology and lode gold deposits of the Nuka Bay area, Kenai Peninsula, Alaska

Richter, Donald H. · 1968 · Report

Nuka Bay is a deep, T-shaped fiord on the southeast coast of the Kenai Peninsula approximately 60 miles southwest of the port of Seward.

This 1968 document, Geology and lode gold deposits of the Nuka Bay area, Kenai Peninsula, Alaska, is preserved in the Mountain Man Mining Library for research and reference. Original source: pubs.usgs.gov.

47, Vj! . , . sa

Is4 ..s Akdc,'1: nn

(.00) USGS LIBRARY - RESTON 3 1818 00082708 7 UNITED STATES DEPARTMENT OF THE INTERIOR 1.-LSEOLOGICAL SURVEY, / /I GEOLOGY AND LODE-GOLD DEPOSITS OF THE NUKA BAY AREA, KENAI PENINSULA, ALASKA by Donald H. Richter Open-file report This report is preliminary and has not been edited or reviewed for conformity with Geological Survey standards or nomenclature.

/' (o000 Weld - Int. 2905 . / 7' ',54/ U. S. GEOLOGICAL SURVEY Washington, D. C. For release JUNE 10, 1968 The U. S. Geological Survey is releasing in open files the following reports. Copies are available for consultation in the Geological Survey Libraries, 1033 GSA Bldg., Washington, D.C. 20242; Bldg. 25, Federal Center, Denver, Colo. 80225; and 345 Middlefield Pd., Menlo Park, Calif. 94025. Copies are also available for consultation in the Brooks Bldg., College, Alaska 99701; 441 Federal Bldg., Juneau, Alaska 99801; 108 Skyline Bldg., 508 2nd Ave., Anchorage, Alaska 99501; 678 U.S. Court House Bldg., Spokane, Wash. 99201; 504 Custom House. San Francisco, Calif. 94111 ; 7638 Federal Bldg., Los Angeles, Calif. 90012; 1012 Federal Bldg., Denver, Colo. 80202; and in the offices of the Alaska Div. of Mines and Minerals, 509 Goldstein Bldg., Juneau, Alaska 99801; 3001 Porcupine Dr., Anchorage, Alaska 99504; and University Ave., College, Alaska 99701: 1. Reconnaissance geologic map of the Tanacross quadrangle, Alaska, by Helen L. Foster. 13 p., 1 map and explanation, scale 1:250,000. Material from which copy can be made at private expense is available in the Alaskan Geology Branch, USGS, 345 Middlefield Rd., Menlo Park, Calif. 94025. 2. Preliminary geologic map of the Eagle B-1 and C-1 quadrangles, Alaska, by Helen L. Foster and Terry C. Keith. 1 map, scale 1:63,360. Material from which copy can be made at private expense is available in the Alaskan Geology Branch, USGS, 345 Middlefield Rd., Menlo Park, Calif. 94025. Geology and lode gold deposits of the Nuka Bay area, Kenai Penin­ sula, Alaska, by Donald H. Richter. 52 p., 1 pl., 10 figs., 4 tables (map scale, 1:63,360). Material from which copy can be made at private expense is available in the Alaskan Geology Branch, USGS, 345 Middlefield Rd., Menlo Park, Calif. 94025.

Contents Page Abstract Introduction Location, accessibility, and geography History of the area . Present study Geology Regional setting Sedimentary rocks tiosous rock. Unconsolidated sedimentary deposAm

Structure Economic geology Gold-bearing quarts veins Description of individual sines, prospects, and quart: veins Locality 1 Locality 2 Locality 3 Locality 4 Locality 5 Locality 6 Locality 7 Locality 8 Economic geology—Continued Description of individual mines, prospects, and quartz veins—Continued Page Locality 9 Locality 10 Locality 11 Locality 12 Other prospects not found Geochemistry of stream sediments Conclusions and recommendations Inferences cited -

Table of Oontants--Illustrations Tables (Plata is in pockst] Plate 1. Geologic map of northwest part of Hai' Bay, Kenai Peninsula, Alaska Piga= 1. Index map &owing location of &aka Bay area Hypothetical geologic section Roos dimes's' showing the average strike of 19 principal quartz wins 4. Geologic map of surface and mine workings at locality 2 Pas. ls Table I. Principal minas and their estimated gold production Physical characteristics of the known principal veins Semiquantitative spectrographic and chemical analyses of ,parts veins Seniquantitative spectrographic and chemical analyses of street-sediment samples Pal Section through nine worki-gs at locality 2 Sketch map of geology said mine ..triage at locality 4 4111411.4n. 11, Geologic map and section of nine workings at locality 8 Sketch map of geology and nine working. at locality 9 Sketch of wins at localities 11 and 12 Geochemical asp of Mika Bay area

Geology and led-gold deposits of the Make Bay area, Kenai Peninsula, Alaska By Donald H. Richter Abstract Nuke Bay is a deep, T-shaped fiord on the eoutheaat coast of the Kenai Peninsula approximately 60 miles southwest of the port of Seward. Gold-bearing quartz veins were discovered in the area in 1918, and betweaa 1920 and 1940 several smell mines were oper4tion around the North and West Arms of the bay. Estim..ted total production say have been as mach as $164,000. Bedrock in the Nuke Say area is a thick Cretaceous section of interbedded slate and graywacks that has been regionally deformed into a series of relatively open, but overturned, folds plunging at low angler to the north-northeast. Except at the MOO, of folds, bedding and foliation (slaty cleavage) are parallel and dip steeply to the northwest. Small granodiorite dikes fill tensional cross joints in the folded sediments, and a few granodiorite sills are intruded along bedding and foliation planes. Quartz veins are abundant throughout the region, but contain significant amounts of gold only in a relatively small area, 8 miles long and 6 miles wide, around North and Hest Arms. The veins are generally less than 5 feet wide and 300 feet long and consist chiefly of massive white quartz. Arsenopyrits with minor amounts of other ealfidea and native gold occurs as irregular masses and pods in the ,uartz. The larger and more productive veins dip steeply and strike seat-west, almost normal to the regional structure, and appear to be confined to competent graywecke beds or dikes. Random channel sampling of the quartz veins indicates gold values as high as 9 ounces - per ton across zones as wide as 2 feet. A study of the stream sediments throughout the area disclosed !several drainages with detectable gold; one, Babcock Creek, contained 0.5 ppm gold, the others from 0.02 to 0.07 ppm. No base metal anomalies war* detected. The area appears to warrant further investigation as a potential producer of small amounts of gold. Diligent smell-scale mining may be economically feasible.

Istredeetion The fanner smell geld-peodecing area at Nuke bay on the feast Peaiasela of Alaska vas the seem of active exploration, developnest, and mining daring the period 1920 throulb 1940. Following World War II and the resumption of domestic gold mining, however, interest in Nuke Say never fully revived, and today the area has been virtually forgotten. This report, a result of iswestigatious under the U.S. Geological Survey's Heavy Metals program, describes the geology and Lode-gold deposits of the area and attempts to evaluate its future mineral potential. Lecatiss4 accessibility, and geography Juke bay is a pressisent T-shaped nabaynent aloes the southeast coast of the Kasai Peninsula in south-central Alaska shout 64 miles southwest of the port of Seward (fig. 1). The area investigated, Figure 1 'sear here which includes nest of the knees Mika Bey Leis-gold deposits, covers about 100 square silos around the West and berth Arne of the bay and is within the Seldavia C-2 and 1-2 15-alauts quadranglign (U.S. Geol. Survey, Alaska Topographic Series, scale 1:63,360). The area is accessible by boat or light aircraft. Seaworthy small craft can make the trip from Seward in about 6 to 8 hours, but running tine may vary considerably depending on the size of the boat and condition of the sea. Float planes can land in most of the sheltered bays, and a privately maintained landing strip at the head of beauty bay is adequate for light, wheeled aircraft. Flight time from Honer, 35 miles to the west, is approximately 25 minutes. From its wide mouth near the outermost Pya Islands, Nuka Bay trends northward for about 8 miles where it splits into two deep, narrow fiords. East Ara, the easternmost and largest of the fiords, extends northeast about 21 sales, penetrating deep into the rugged Lanai Mountains. West Ara and its continuation, North Arm, which together constitute the smaller fiord, extends oorth on an irregular course for about 12 Riles. The mouth of Nuke Bay opens directly into the Gulf of Alaska, leaving much of the area within the Bay susceptible to rough water during periods of storm and strong onshore winds.

3o 165 ZO Figure I. Index map of the southern Kenai Peninsula, Alaska showing location of the Nuka Bay area.

The commtry is one of extremely rugged topography, with a maximum relief of over 3,500 feet in the area imeastigated. Vertical to searvertical cliffs are present on many of the mountain slopes throughout the area, waking overland traverses extremely difficult. Valley glaciers, often extending down to 500 feet above see Level, still occupy many of the Larger streams valleys, and ice fields and meow cover much of the more gentle terrain above 2,000 feet. An extensive plain of recent glacial outweak, only a few feet above sea level, fills the Nuke liver valley at the bead of Beauty Ray, off West Ara, and Lesser outw.ab deposits are present at the head of Borth Arm and some of the larger bays. lock exposures are excellent along most of the shoreline but are locally inocceesibla beoeuse of cliffs. Demos spruce forest meatle most of the bedrock between high-tide level and about 500 feet in elevation; but above 500 feet, if snow and ice are absent, exposures are generally good. History of the area In 1909, at the time of the U.S. Geological Survey's first reconnaissance of the southern Kenai Peninsula, at least three claims had been staked for gold in the Nuke Bay area (Martin and others, 1915, p. 229-230; Grant and Higgins, 1910, p. 174). Two of these claims were in East Arm and of no significance. The third, from the description of 'Grant and Higgins, was apparently on the granite dikes near locality 6, the former Rosness and Larson mine (see p. 33), on the west side of North Arm. However, it was not until about 1918, almost a decade later, that the gold is reported to have been discovered in the Nuka 'Bay area (Smith, 1938, p. 26). Shortly thereafter, many claims were staked, and by 1924 more than half a dozen properties were in the process of development including a mill under construction at the Alaska Hills mine. Peak activity in the area was reached in the early 1930's when at least four mines, each with its own mill, were producing gold. Toward the end of the 1930's, activity slowly waned, and by 1940 only two properties--the Nukalaska and Sonny Fox mines--were operating. A measure of the size, economy, and needs of the Nuke Bay mining community during its peak years was the finding of a 30-gallon whiskey still in a secluded cove in Beauty Bay. Evidently the community was large enough to support local industry whose products were not normally available in the mining camp and had progressed to the point where nonessential commodities were in demand.

Since World War II there has been very little activity in the lulus Bay area. A group from Maveii sere apparently unsuccessful in attempts to reopen the Dinka asks mina sometime in the 1950's (according to local !fishermen), and in 1959 and 1960 a party from Seward was working in the Beauty Bay area (Williams, 1959, 1960). In 1965 a mining group from Jamestown, Ohio, acquired the former Little Creek prospect (loc. 2); by the fall. of 1967 a mall mill had been constructed, and a limited amount of ore mined. After Grant and Higgins' geological reconnaissance of the Kauai Peninsula in 1909, Nuka Bay was not examined again until after the discovery of gold. Pilgrim (1933) gives an account of reports on booms deposits by territorial mining engineers 44 visited Nuke Bay in 1924, 1925, and 1931; an &nomination of the mimes and prospects in the area by S. 8. Capps of the U.S. Geological Survey in 1936 is described by Smith (1938). Both of these papers have been extremely helpful in the preparation of this paper. A rough approximation of the total value of gold produced in the Nuke Bay area is about $166,000. Table 1 lists the five known gold TABLE 1 NEAR HERE producers in the area and their estimated production with some data on their underground workings sod sill capacities. The production figures for the Alaska Hills mina, Goyne prospect, and for the first 6 years of operation at the Sonny Fox mine are from unofficial reports (Pilgrim, 1933). For the remaining mines and the last 9 years of operation at the Sonny Fox mine, the estimates are based on an average yearly production of 200 tans with an average grade of $25 per ton.

Table 1.--Principal mines and their estimated gold production Approximate Approximate total length of Capacity of value of Locality underground workings— mill Years of gold produced No. Name (feet) (per day) production (dollars) Nukalaska mine 24 tons 1934-1940 [35,000] Alaska Hills mine Unknown 1924-1931 45,000 Rosness and Larson mine 4 tons 1931-1933 [15,000) Goyne prospect No mill 1931-1934 41,000 Sonny Fox mine 1,000 7 tons 1926-1931 25,000 1932-1940 [45,0001 Estimated total value of gold produced $166,000 1 / — Exclusive of raises, stopes, and shafts. Figures in brackets are estimates based on an average production of 200 tons per year with an average grade of $25 per ton. 8a (p. 9 follows)

Present study Recent interest of private enterprise in the small lode-gold deposits of Nuka Bay and the lack of detailed geologic information in an area once known to have produced a limited yet significant amount of gold were the main factors which prompted this investigation. Fieldwork occupied the period June 2-30, 1967. The investigation included: geologic mapping (scale 1:63,360) of about 35 miles of shoreline and 20 miles of overland traverses, geochemical sampling of 44 streams for trace-element analyses, and detailed mapping and sampling of the accessible gold deposits. Water travel in the area was by 14-foot skiff and outboard motor, which on a number of occasions proved too small to safely negotiate the rough waters of the bay. The writer was assisted by volunteer helper, Ronne C. Richter, throughout the entire period of field study and by geologic field assistant, Richard A. Brocklehurst, during the last half of the field study. Geology Regional setting The Muka Bay area is in the Chugach Mountains syncline, one of the major arcuate tectonic elements in south-central Alaska. Filling of the georyncline with clastic marine sediments probably as early as the late Early Cretaceous and continued up to the end of the Late Cretaceous (Payne, 1955). The bulk of the sedimentary deposits, however, are apparently middle Late Cretaceous and younger in age (Miller and others, 1959, p. 15). At the close of the Cretaceous, or possibly as late as the close of the Paleocene (Payne, 1955), the sedimentary rocks of the geosyncline were uplifted and strongly folded during the Larmaide orogeny. Accompanying igneous activity resulted in the intrusion of many stocks and smaller bodies of crystalline rock... Following the orogeny, uplift continued through the Tertiary and probably reached a maximum during Pliocene time. Sedimentary rocks The geoeynclinal rocks in the Nuke Bay area consist of interbedded slate and graywacke with minor argillita, siltstone, locally calcareous, conglomerate, and phyllite. With the exception of some massive graywacke units and conglomerate beds, the rocks are thin bedded, ranging from a fraction of an inch to generally less than a few feet thick. The contacts between individual beds may be gradational or sharp; local disconformsties resulting from slump, scour, or other submarine erosion processes are common.

Graywackap the predominant rock type in the area, ranges in color from light to desk gray and in grain size from fine to coarse. Weathered surfaces are lighter colored, giving the rack a bleached appearance. The massive graywacke units may be as such as a few thousand feet thick without obvious bedding or discernible change in texture. Along strike, beds characteristically thin, swell and pinch out. Some of the massive grwroacke units can be traced for a few males, apparently occurring as large lenses in the thinner bedded rocks. Lithic fragments appear to constitute a Large bulk of the rock, and in some of the massive units, scattered cleats of slate or siltstone, as much as 5 inches in di4far, are common. Graded bedding is wall developed in some of the thinner bedded units; individual graded beds range from less than an inch to more than a foot in thickness. A typical graded bed consists of a base of fine-to medium-grained graywecke that changes gradually upward to dark siltstoue or slate. The graywacke beds are not foliated, and the more massive units tend to be coarse grained and homogeneous. The dark, finer grained, clastic rocks are mostly slates and siltstones that generally exhibit a well-developed foliagton (slaty cleavage). However, many of the coarser siltstones are not foliated, and occasionally dark massive ergillites are present in the thin-bedded sections. Locally, in WOOS of strong shearing, the fins-grained rocks are phyllitic with visible secondary micaceous minerals. Aloft most of the north shore of Pilot Harbor (pl. 1), iron-stained phyllites are especially abundant--same coarse enough to be classified as dark micaceous schists. Conglomerate beds are scattered throughout the section. Slaty conglomerates, with slightly stretched cleats of slate and coarser sediments, are locally present in most of the thin-bedded strata. Along the east side of Surprise Bay, beds of pebble-cobble conglomerate as much as 100 feet thick are especially common. These rocks are compoaed principally of cleats of reworked graywacke and siltstone set in a graywacke matrix. CLIcareous siltstones were observed along the northeast shore of Beauty Bay where a few thin beds are interbedded with slate, graywacka, and normal silistons. Theme limy rocks weather brown in contrast to the gray weathered surfaces of the normal siltstones and graywackes. Igneous rocks Light-colored thin dikes and sills, chiefly of granodiorite, occur sporadically throughout the area; at two mines (lots. 1 and 8) they are the host rock for gold-bearing ,uartz veins. Host of the intrusive rocks occur as dikes, probably filling tensional cross joints formed during regional folding; a few occur as sills intruded along bedding and foliation planes in the slates and graywmckes.

In hand specimen the dikes and sills are dense light-gray rocks generally exhibiting a few small altered amphibole and plagioclase phenocrysts. Under the wicroecope the rocks have a subhedral granular texture, locally trachytic, with a groundmass grain size ranging between 0.2 and 1 sm. A typical dike consists of small laths of aodic andesine (50-60 volume percent), inter1ath filling of potassium feldspar (10-20 volume percent), quartz (5-15 volume percent), and scattered opequa minerals (1-2 volume percent). Secondary chlorite, white mica, and carbonate are generally present in widely varying amounts and collectively may constitute as much as 20 volume percent of the rock. The dike at the Goyne prospect (loc. 8), which is as much as 100 feet thick, is one of the coarsest grained intruaives (average grain size 1 ma) observed in the area. The rock is nonporphyritic and contains no primary mafic minerals, but abundant chlorite (10 volume percent) occurs in ill-defined patches and as scattered interstitial filling. Also abundant throughout the rock are veinlets of coarsegrained quartz, zoisite, and potassium feldspar. No large intrusive bodies were observed in the mapped area. Abundant float of crystalline rock in the stream issuing from the glacier in the extreme northwest corner of the area (pl. 1, temple site 025) may be indicative of a large intrusive mass underlying the ice to the west. The rock is quartz diorite with a eubhedral granular texture containing coarse-grained andesine (average grain size 3-5 mm), quartz, and minor potassium feldspar. Zones of strong granulation, containing comminuted mineral particles and locally replaced by abu,dant carbonate, are common throughout the rock. The large crystalline rock mass on the ?ye Islands and on the east side of East Arm (fig. 1) mapped by Martin, Johnson, and Grant (1915) was not examined during this study. The igneous racks cut rocks as young as Late Cretaceous and therefore are considered to be Tertiary(?) in age. Unconsolidated sedimentary deposits Holocene unconsolidated glacial and glaciofluvial sedimentary deposits fill.;the heads of the bigger bays in Sorth and West Arms (pl. 1). The largest of these outwesh deposits forms an extensive plain more than 3 miles long and 1 mile wide at the head of Beauty Bay. The deposits are almost entirely glacial in origin but are now being reworked by present streams and, locally along the beaches, by wave and tide action. Remnants of moraines are scattered along the sides of the outwash flats, generally forming low ridges or mounds parallel to the mountain fronts.

Alluvial fame have developed at the mouths of some of the Larger high-sradiamt streams, and talus cover, many of the steeper slopes throughout the area. Structure Bedding and foliation (slaty cleavage) in the sedimentary rocks of the Nuke Bay arms strikes between north and N. 40 I., giving rise to the pr000unced northeast-trending structural grain of the country. These planar structures generally dip moderately to steeply northwest and are parallel except at the nose of folds or in local areas of strong Shearing. Based on many observations of miner folds and one major fold (from a distance) the rocks have apparently bean deformed into a series of rotatively open overturned folds with both limbs dipping northwest. Lccally the minor folds are not overturned and probably represent gentle warps on the limbs of Larger structures. Feld axes on most minor folds plunge at law angles (5'-15') to the northeast. This folding is hypothetically depicted in the cross section in figure 2. Figure 2 near here No major faults were observed in the area, but they could easily be overlooked because of the monotomy of section and abeeoce of marker beds. Minor faults are common, especially in the more competent beds, and zones of strong shearing, with little or no discernible offset, are Sete or Locally present Ln theyslate-graywacks units. Jointing Ls conspicuous in many of the massive graywecka units. The principal joints Strike about N. 60*-80* W. and dip vertically or steeply southward, normal to the fold axes. Many quartz veins and some dikes in the area have this same general orientation, Which suggests that their formation was comtrelled in part by J pointing. Economic geology Gold-bearing quartz veins Quarts veins are ubiquitous throughout the Nuke Bay region, but they appear to contain significant amounts of gold only in a relatively small area approximately 8 silos long by 6 miLes wide around North and West Arms. The salient physical Characteristics of most of the known sold-bearing veins are listed in table 24 more detailed descriptions TABU 2 NEAR HERE are presented in the section describing the individual mints and prospects.

a

,- a a

40.0' — 30.0' — a CO Zoo& — / / I 000' / r i " , I 1... / / , / , ', --, , /;/ / / 1 :/i 5e. ­ / / / ; -7.77777:74 ,

Taole 2.--Physical characteristics of the known principal veins Locality Elevation Average Length-I Maximum width No. Name (feet a,ove sea level) attitude (feet) (feet) Country rock Nukalaska mine 2,150 E.-V.; 80 ° S. Contact of dike and slate-grayvacke Glass-lleifner property E.-V.; 40°-60° N. Graywacke N. 80° V.; 8',° N. Graywacke N. 850 V. ; 81° N. Contact of graywacke and slate Alaska Hills mine E.-W.; 55° N. Graywacke E.-W.; 55° N. [751 ? Nuka Bay mines prospects 1,120-1,400 N. 85° W.; 82° N. [151 Slate-grayvacke N. 85° W.; 76 ° S. (201 Graywacke-siltstone Frank prospect N. 52 ° 11.; 79 ° N. [501 Slate Rosness and Larson -line N. 30 ° F.; 67 ° S. [301 Graywacke E.-W.; 80 ° S. [20' ? Graywacke Hatcher prospects N. 70 ° W.; vert. Graywacke-conglomerate-slate N. 80° W. 70 ° N. [20' Graywacke-conglomerate Coyne prospect N. 85° E.; 7 -) ° S. Dike Sonny Fox mine N. 75 E.: -rt. (A) Slate N. 70' E. 60° W. Graywacke Skinner prospect N. 80° E.; 72 ° S. f401 Graywacke Locality 11 N. 80° E.; 70° S. [5( Graywacke Locality 12 N. 80° E.; vert. (51 Graywacke 1 - Figures in brackets are minimum lengths for veins of limited exposure in pits, adits, and poor outcrop. 16a (p. 1; follows)

The gold-bearing quartz veins are characteristically short and narrow, rarely longer than 350 feet or wider than 5 feet. Zones of veins, however, such as at the Groyne prospect (loc. 8) or the Golder' Goose vein (p. 32), may be as such as a few thousand feet long. The Larger and more productive veins appear to be confined to the competent massive graywacks beds and dike rocks or locally along the contact between these rocks and thin interbedded graywecka and slate. Typically the vein* are very irregular and pinch and swell over short distances. They also frequently split and recombine, resulting in abundant inclusions of country rock in the vein system. All veins striking into slate or thin interbedded slats and greymecks from massive grayeacks or dike rock splay lets several thin quartz stringers that follow bedding or foliation plane/in the thin-bedded strata a short distance before pinching out. Some vein structures consist of a relatively large, well-defined quartz vein with quartz stockworks along one or rarely both wells. Quartz stockworks unrelated to any Larger vein structure amd without any preferred treed are fairly common in some of the massive graywecke units. Contacts between veins and country rock are sharp. Locally, the vein walls are slickensided; in a few cases a thin clay gouge sone may be present between vein and wellrock, out hydrothermal alteration is not apparent. Most quartz veins in the Nuke Bay area strike east-west, almost normal to the regional structure, and dip steeply to vertically. Some stockworks, as mentioned above, however, show no particular orientation, and a few smaller veins follow bedding and foliation planes in the sedimentary rocks. A rose diagram of the strikes of the 19 principal veins listed in table 2 is shown in figure 3. Although constructed Figure 3 near here with data from a few observations, the diagram does illustrate the preferred orientation of the principal veins. The mineralogy of the quartz veins is not complex. The veins ere hydrothermal fissure-fillings and show no observable change in structure or mineralogy through a vertical range of more than 2,000 feet. Massive, crystalline, white to light-gray quartz, locally exhidting a Sheeted or layered structure, constitutes more than 95 percent of the vein material. Sulfides, chiefly arsenopyrite, occur as irregular masses, lenses, and stringent either scattered through the vein -,uarr7. or, if the vein is sheeted, in zones separating distinct layers of massive quartz. Minor and extremely variable amounts of pyrite, chalcopyrite, galena, and sphalerite associated with the arsenopyrite have been observed in polished sections. Capps (in Smith, 1938, p. 27) also reported that tetrehodrite, vocellite, and chalcopyrite are present. Native gold occurs principally as smell wiry segregations or thin irregular plates generally in sulfide masses or in uartz near sulfides, Polished sections reveal some gold occurring in microscopic blabs in the arsenopyrite.

Figure Z. Rose diagram showing the average strikes of 19 principal quartz veins in the Nuka Bay area. Other data for these veins are given in Table 2.

Spectacular gold spechmeas have been found in many of the mines, and even some mine-run ore has had remarkably high tenor. Capps (in Smith. 1938, p. 26) mentioned a shipment of 5 tooa of ore from the Sonny Fox ulna yielding $530 a ton, and at the MukaLaska mine a several-weeks run of diluted ore averaging $100 per ton. The gold values are erratic and vary greatly from place to place along the same vein. Moreover, altbomgh a genetic relation is apparent between the gold and sulfides, the presence of abundant sulfides does not necessarily imply high gold values. tandem channel samples collected during this study ran as high as 300 ppm gold (Table 3, ACH-061), or TABLE 3 HEAR HERE about 9 ounces per ton, and many mere in the range of 1-200 ppm gold. Oxidation has locally altered the sulfide minerals to depths as much as 200 feat, but there is no evidence of secondary enrichment. In areas of relatively strong oxidation, the arsenopyrite is generally enclosed in a shell of fins-grained yellowish-green dscepoaition products (scorodite?) and the vein quarts is conspicuously stained by limonite. The hundreds of barren uartz veins exposed throughout the area are similar in form, size, and probably genesis, to the *mineralized veins except no sulfides were observed. In figure 10 the larger barren itlartz veins or areas with an unusual number of 'barren quartz veins have bean noted. Veins in six of these areas have also ,sen sampled (ACH-010, 013, 017, 024, 059, and 079) and analyzed for gold and trace elements in an attempt to determine if they show any significant metal values (table 3). Only two samples (ACH-059 and 079) contained detectable gold values, and none were anomalous in other elements. The two samples with detectable gold both contained 0.07 ppm; one (AC8-059) is a composite grab sample from a number of quartz veins exposed at an elevation of 2,000 feet west of locality I and the other (ALB-079) is a composite grab sample of six veins across 100 feet on the west side of Ariadne Island. The orientation of the quartz veins suggests that they fill tensional cross joints formed during, and as a result of, the regional folding. The preponderance of veins in massive grayvecke and dike rock suggests further that the tensional stresses during folding were relieved in these rocks by fracturing and mechanical deformation, Whereas the slates and thin-bedded graywacka deformed plastically.

Table 3.--Semiquantitative spectrographic and chemical analyses of quartz veins (In parts per million. Analysts: Semiquantitative spectrographic analyses, Arnold Farley, Jr.; atomic absorption (gold) and calorimetric (arsenic), W. L. Campbell, R. L. >tiller, T. A. Roemer, and A. L. Meier. A, not detected. Numbers in parentheses under elements is lower limit of determination in ppm.] Sample Aul d As3-/ Ag B Ba Co Cr Cu Ni Pb Sb Zn No. (0.02) (10) (0.5) (10) (20) (10) (10) (2) (2) (10) (100) (200) Mineralized Quartz Veins ACH-015 1,200 A

A A A A A ACH-038 2,400 A A A A A ACH-039 6,000 A A A A A ACH-040 1,200 A A ACH-041 4,000 A A A ACH-048 A A <10 A A A A A ACH-049 6,000 A A ACH-050 A <10 A A A A

A Ach-051 A &lt;10 A

A A A

4,000 A ACH-060 2,400 A A A A ACH-061 2,400 A A A A ACH-062 A A A A ACH-080 A A ACH-081 1,500 A A A A ACH-082 2,000 A A ACH-083 1,500 A ACH-084 A A A ACH-085 A A Barren Quartz Veins ACH-010 A A A A A A ACH-013 A A A A A A ACH-017 A A A A A A A ACH-024 A A <10 A A A ACH-059 A A A A ACH-079 A <10 1,000 A A A 1 / — Atomic absorption. Colorimetric.

Description of individual mines, prospects, and :;uartz veins Locality 1 CMukalaska Mining Company; Honolulu group) The Nukalaska mine is on a precipitous north-facing mountain slope 1.2 miles southwest of the head of Shelter Cove in Beauty Bay at an elevation of about 2,150 feet above sea level. The caved portal of the sine is difficult to reach and extreme cars must be used in the climb. Although reportedly one of the richest deposits in the area, very little work was done on the vein after its discovery in 1926 (Smith, 1938, p. 28) until about 1933 when the Nukalaska Mining Company began active development. Production probably started in 1934 or 1935 and continued up to 1940, but the work waa hampered by a fire in 1938 (Smith, 1939, p. 29) and heavy enowjlidea during the winter of 1938-39 (9eith, 1941, p. 25). After World War II, a group from Hawaii, locally referred to as the Honolulu group, attempted to reactivate the mine but the venture was apparently short-lived (comments by local fishermen). At the time of our visit in June 1967, the road from Shelter Cove to the mill and camp at an elevation of 150 fast was oWmormed, and the A mill equipment and camp buildings had been destroyed by man ,ind weather. An aerial tram, however, with vertical drop of about 1,900 feet, that rune from the mina edit down to a terminus three-eigh of a mile west of the mill, was still standing. Southeast of the mill the remains of another aerial tram, or possibly one that was under construction in 1940, extends up the east face of the mountain. Locally slickenaidad vein walls and minor gouge and ''reccia in the veins indicate some structural readjustment following vein deposition, nit in general it appears that the veins were emplaced during the end period of folding. Dike intrusion probaAy occurred more or less contemporaneously with vein formation or just prior to vein formation. The source of the ore solutions responsible for the deposition of the gold-bearing veins and the apparent confinement of veins to a relatively small area are probably related problems neither of which are well understood. The mineralogy and structure of the veins are characteristic of mesothermal-hypothermal deposits, implying deposition from magmatic solutions under high pressures and moderate to high temperatures. In the gold-bearing area, however, the only igneous rocks known are a few small dikes and sills, and although they are spatially related to some veins, they do not appear to a the immediate source of any ore solutions. The nearest known large crystalline rock mass is exposed on the east side of East Arm and the Pye Islands, approximately 5 miles from the southeast corner of Ehe mapped area (fig. 1). This body of granite (Martin and others, 191 , p. 228) or more likely a hypothetical parent batholith underlying the western part of Nuke Bay maybe the source of ,)oth the granodiorire dikes and the ore-bearing quartz veins in the area. 2/

Two attempts to scale the mountain slope directly below the mine ous proved futile because of steep cliffs, and on one day, almost continual snow avalanches. A third attempt, by a devious route up the valley to the snowfield south of Mount Diablo (see pl. 1) and then back down the ridge to the mine, was successful only to find the workings inaccessible due to caved timbers at the portal. Four hundred feet vest of the mine at the end of a goat trail cut into the face of the cliff, a small bunkhouse still stands cabled on a narrow ledge. As neither the underground workings nor the surface exposures could be examined during our visit, the following geologic information is quoted directly from Capps (in Smith, 1938, p. 28-29): "The vein crops out on the crest of a high, rugged ridge that rises about 2,500 feet above sea level and is so steep as to be difficultly accessible. To mine it an adit was driven 30' W., into the face of a cliff 200 feet below the outcrop, and at a distance of 230 feet it encountered the vein, which strikes west and along which crosscuts were driven 175 feet westward and 200 feet eastward. East of the edit little profitable ore was encountered, but to the west a rich pay shoot was cut, and from it all the gold so far recovered has been taken. At the time of visit, in August 1936, eight ore chutes 20 feet apart had been opened up, showing a width of the ore shoot of 140 feet, and stoping Was in progress up to a point 80 feet above the edit level. The ore shoot rakes considerably to the west, perhaps as much as 45'. Surface prospecting indicates that a second ore shoot exists some 250 feet east of the one now mined, out this shoot has not yet been encountered in the underground workings. "The vein strikes about due east, almost at right angles to the east-northeastward-striking slate and graywecke of the country rock, dips 800 S., and lies parallel to and along the footwall of a 12-foot dike. 23 (p. 23a follows)

The vein ranges from 10 to 18 inches in thickness and consists of banded quartz, more or less oxidized to such depths as have so far been reaching by mining. Spurs from the vein branch diagonally eastward into the dike, !int these are of lower grade than the main vein. Some small Lenses of ore show at the surface in the slate on the hanging wall of the dike but have not been found underground. Both vein and dike are cut and displaced by a small northwestwardtrending fault at a point 275 feet west from the main edit, but vein matter persists along the jog formed by the "The dike rock, as examined in thin section, proves to be a quartz diorite in 'kith the principal minerals are quartz, lime-soda feldspar, and calcite, with sericite and chlorite as secondary minerals. The ore consists of somewhat banded carts, carrying visible particles of arsenopyrite, pyrite, chalcopyrite, galena, and free gold." Locality 2 (Little Creek prospect; Earl Mount prospect; Glass and Heifner property) This prospect, presently being developed byPiessrs. Giass and Heifner of J.mestown, Ohio, is 0.9 mile northwest of the northwest corner of Beauty Bay at an elevation of 200 feet above sea 12ve1. good road leads to the property from an airstrip on the Nuka River flats at the edge of the bay. The gold-quartz veins on this property were discovered in 1924, and by 1925 a 50-foot edit had been driven and a number of opencuts and pits excavated (Pilgrim, 1933, p. 44-46). In 1932-34 the edit was driven another 400 feet and a raise extended to the surface (Smith, 1938, p. 32). This work reportedly failed to discover ore and since then until 1965, when the property came under control of Glass and Heifner, it apparently had lain idle. Glass and Heifner have erected a mill, machine shop, and comfortable bunkhouse; in 1967 they started surface mining the northernmost of the veins. The milling equipment consists of two jaw crushers, a 4-foot call mill, and a Wilfley concentrating table. 23a (p. 24 follows)

A geologic map and section of the underground workings and surface exploration is shown on figures 4 and 5. All of the underground Figures 4 and 5 near hers moss-we workings are inft thick-bedded graywecke. Black slate and siltstona, with thin interbedded graywacks, is exposed on the surface in all the easternmost and southeasternmost pits. Foliation in the finer grained clastic rocks and bedding trends about N. 10'-30' E. and dips 50*-60' NW. Where the slate and massive graywecka are in contact, however, the slate is generally severely distorted. No dikes ware observed. At least throe major quarts veins have been discovered and explored on the property. All the veins have an average east-west strike and dip vertically to 40' N. The veins are confined to the massive grayvacke or graywacke slate cO7ntact; where they continue into the slate, they thin, split, and generally feather out. The northernmost and probably the principal vein on the property is sporadically exposed in the surface workings for a distance of 350 feet and underground for 125 feet. At its western extremity, the vein has a consistent moderate dip (40'-67") to the north, but toward the east steepens to more than 80' N. The vein ranges from less than 1 foot to as much as 5 feet in width. Locally the vein splits, or is sheeted, with horses of graywacke between the quarts. Many of the splits continue into the graywacke at angles of 10*-30° where they apparently pinch out. Slickensides on the hanging wall plunge 35' to the northeast. Massive sulfides, chiefly arsenapyrite, occur in lenses, sheets, and irregular masses throughout the vein system. TIP° samples (ACM-038 and ACM-039) cut at random across the vein in the drift assayed 72 and 0.2 ppm gold respectively (fig. 4). A second and much shorter vein is exposed 100 feet south of the eastern half of the main vein in two surface trenches 100 feet apart. The vein dips 84'-87' N., is 0.3 to 1 foot wide and contains only minor amounts of sulfides. It apparently does not extend down to the level of the adit. Sixty feet farther south a third vein is exposed in many pits and opencuts over a distance of 150 feet. The vein is also exposed underground along a short drift off the main edit and has been raised on from this drift to the surface. Underground the vein has a maximum width of about 2 feet, but near the raise the vein splits and appears to '.be pinching out to the west. At the face of the drift, 20 feet ,est of the raise, only the northernmost split, with a width of 0. feet, is present.

/V Mple Acm - 03

Widtk Cif) 2.5' Jon SAMPLE ACH 039 7Z 1.0' 3.0' GrarJack. 0.3* V tin Au (Ptiii) ""(4) cy 6cf 20'

ovoirvirouic„). opict.ots or1 9.-/korea.cice. Air.? CV Ga79i DISTORI3G9 A k'? E A tar.>1 „„ Si' N / 5. ,.\cse lig / k 1/ /// / / Z Z 79-Z / / 2' dean / / / ../D2. i.I OA 87' ./ ,./ / ' 1.5' ' /' 9 ubla 9.1.1 OW caos4 shaft 4 M., stri,s,.., probe1.11 comecTs caltL .{1..13 mese. tr.. aeht. 0, I WC. C .4,fica Ve In At 1,116.1lat gMy.oa cka L .MIt SI L...+ .4 .1,ifo.6.1 ZS So 10 0 iett

Quart} VC,,Show a.,4 wi44, (2" Pe p t .ern c.t" Figure*. Geologic map of surface and mine workings Mar fce ta.c.. CoiAps.c.s Surua.t b'i 0.H W10.J..-, at locality 2 (Glass and Heffner property), Nuka Bay area, Alaska

/I/ ? sect- .n 'n Pr. E. ektens ow,ti>---7/ S utiote.e.. O de°ROP.LIC. txrtenuon t0 ,101CC IA, I?

A Tok.yoLs Aft.1 yams p 1; se cb4 04. ACH - e? -77:1 A section S C-1-e.4 -(31 ; I 00 k east0 ZS So toe tet. Figure S. Section through mine workings at locality 2 (Glass and Heffner property), Nuka Bay area, Alaska

On the surface the vein has a maximum width of slightly more than 4 feet, thins to 0.6 feet at its westernmost exposure, and apparently pinches out in black slate to the east. black slate forms the hanging wall of the vein in the first large pit east of the vertical pro j ection of the adit (fig. 4). In this pit the vein averages 1.5 feet wide and extending from it are a number of splits that follow the curved foliation in the slate. In the next pit oast, the vein is back in graywacke, about 3 feet south of the slate-grayvacke contact. Farther to the east the vein was not seen, and only slate is exposed. Arsenopyrite is again the principal mineral in the sulfide-bearing parts of the vein. In the easternmost pit exposing the vein, native gold is relatively abu.dant and good specimens of wiry messes of gold, as much as three-sixteenths of an inch in diameter, can be easily obtained. Underground, a channel sample (ACE-040) across 2 feet of the vein near the raise assayed 2 ppm gold. Numerous smaller uartz veins and veinlets, generally arren of sulfides, are exposed throughout the underground workings. The largest of these, probably a split off the larger vein exposed a few feet north in the raise drift, shows considerable clay gouge and sulfate efflorescences al ng its walls. A 1-foot channel sample assayed 1 ppm gold. 2; Locality 3 (Alaska Hills nines Corporation) The mines of the former Alaska Hills nines Corporation are 1. -1 miles due north of the northeast corner of beauty :;ay at an elevation of 3.7 . to i70 feet above sea level. The camp and mill site, 0.3 mile south of the mine workings on the east bank of the Nuka River, are best reached by a bulldozer trail that eztands across the Nuke River flats from the road to the Glass and Haifner property (loc. 2). The veins on the property ware discovered as early as 191:' and between 1923 and 1931 were developed and mined (Pilgrim, 1933, p. 46; Smith, 1938, p. 29). At the time of our visit in June 1967, the mill had ueen dismantled and burned and the camp buildings were all collapsed. Only two edits in the mine area were found, and one of these, at the upper terminus of an aerial tram from the mill, was caved at the portal. These edits, at an elevation of aOout 3; -) feet, do not fit too wall the description of the workings given by Pilgrim (1933, p. 46-43 and quoted in part below), but it appears that the main workings were above those seen by us and snow-covered at the time of tour search. The accessible edit, about 200 feet north of the edit at the terminus of the tram, is approximately 110 feet 1Gng and entirely in massive graywacke. The adit trends N. 80.E. for the first :7.o 90 feet and then swings slightly to i=east-west course. No ve;ns were observed. At the caved edit, vein ,uartz with arsenopyrite and pyrite was observed on the tailing pile and a gran sample of this material (ACE-015) assayed 0.3 ppm gold.

The following description of the underground workings and geology is quoted from Pilgrim (1933, p. 46-47): tunnels "Development work has been carried on in four separate 4alammolo. The uppermost tunnel, which is at an elevation of ';'/O feet above tide level, has a length of 125 feet. Above this tunnel the vein has been mined to the surface and is not accessible for examination. The present operating tunnel, which is at an elevation of 495 feet, has a total length of about .0 feet. This tunnet.intercepts the vein at a point 118 feet from the portal, at which point the vein is 6 inches in width, strikes easterly and dips 55* N. From this point the tunnel follows the vein for a distance of 50 feet to a fault, the strike of Which is N. 5.E. and which cuts off the vein. At its intersection with the fault the vein is 30 inches in width. The vein quartz is white and crystalline and contains metallic sulphides in considerable quantity. At a point in the tunnel about 35 feet west of the fault a wine has been sunk on the vein to a depth of 40 feet. From the point at which the vein is cut off by the fault the tunnel has been driven southerly al,mg the fault plane for a distance of 5H feet and thence easterly, approximately normal to the fault plane, for a distance of about 100 feet where the faulted segment of the vein was intercepted. From this point a drift has been extended on the vein westerly for a distance of feet, vhere the vein is cut off by a fault plane, and easterly a out 29 (p. 29a follows) 40 feet, where the vein separates into scattered stringers and apparently terminates. The ore between the operating tunnel and the upper tunnel level has been stoped. The wall rock exposed in the operating tunnel is graywacke with the exception of that penetrated by the last 60 feet of the tunnel which is slate. Where the vein enters the slate it becomes narrower and, as stated above, gradually 'Jecomes dissipated into scattered stringers. "From a point about 280 feet northwesterly from the portal of the operating tunnel and at an elevation of 370 feet a crosscut tunnel has been driven a distance of 16'i feet that is so directed as to intercept the vein at the lower horizon. (Authors note: This may be the adit at the terminus of the tram.1 This objective has not yet . )een reached, About 350 feet northerly from the Alaska Hills vein, above described, is the Ehmswiler vein, upon which has been driven a tunnel 75 feet in length. This vein is said to have a width of from 6 inches to 20 inches and to be parallel to the Alaska Hills vein." 29a (p. 30 follows)

The following description of the underground workings and geology is quoted from Pilgrim (1933, p. 46-47): work has been carried on in four separate eMeame40. The tub. The uppermost tunnel, Which is at an elevation of 'i70 feet above tide level, has a length of 125 feet. Above this tunnel the vein has bean mined to the surface and is not accessible for examination. The present operating tunnel, which is at an elevation of 495 feet, has a total length of about 3.0 feet. This tunnel.intereepts the vein at a point 118 feet from the portal, at which point the vein is 6 inches in width, strikes easterly and dips 55' N. From this point the tunnel follows the vein for a distance of 50 feet to a fault, the strike of which is N. 5.E. and which cuts off the vein. At its intersection with the fault the vein is 30 inches in width. The vein quartz is white and crystalline and contains metallic sulphides in considerable quantity. At a point in the tunnel about 35 feet west of the fault a wise has been sunk on the vein to a depth of 40 feet. From the point at which the vein is cut off by the fault the tunnel has been driven southerly al,:ng the fault plane for a distance of 5; feet and thence easterly, approximately normal to the fault plane, for a distance of about 100 feet where the faulted segment of the vein was intercepted. From this point a drift has been extended on the vein westerly for a distance of 50 feet, where the vein is cut off by a fault plane, and easterly a ,oui: 29 (p. 29a follows) 40 feet, where the vein separates into scattered stringers and apparently terminates. The ore between the operating tunnel and the upper tunnel level has been stoped. The wall rock exposed in the operating tunnel is grayuacke ,ith the exception of that penetrated by the last 60 feet of the tunnel which is slate. Where the vein enters the slate it becomes narrower and, as stated above, gradually becomes dissipated into scattered stringers. "From a point about 280 feet northwesterly from the portal of the operating tunnel and at an elevation of 370 feet a crosscut tunnel has been driven a distance of 165 feet that is so directed as to intercept the vein at the lower horizon. [Authors note: This may be the adit at the terminus of the tram.) This objective has not yet been reached, About 350 feet northerly from the Alaska Hills vein, above described, is the Ehmswiler vein, upon Which has been driven a tunnel 75 feet in length. This vein is said to have a width of from 6 inches to 20 inches and to ,e parallel to the Alaska Hills vein." 29a (p. 30 follows)

Locality 4 (Auka Bay Hines Company) The prospects of the former Nuke Bay Hines Company are at an elevation between 1,120 and 1,400 feet above sea level and about onehalf mile east of the northeast corner of Beauty !lay. A foot trail, now almost completely covered with growth, leads to the prospects from a collapsed cabin at the mouth of the first stream north of the bay. Apparently all of the exploration and development work on the property was done before 1931 (Pilgrim, 1933, p. 49- 50) and even iy the time of Capps,' visit in 1936, the buildings and equipment were shoving the effects of exposure (Smith, 1938, p. 30). At the present time no buildings remain standing in the prospect area, and the tailing pile at the portal of the long exploration tunnel is largely grown over with alder. A geologic sketch map of the observed surface and underground workings is shown in figure 6. At the time of our visit in June 1967, figure 6 near here however, the mountain was covered by thick clouds, limiting visibility to less than 100 feet. Hence, it is very likely that some of the exposures mentioned )y Pilgrim (1933) were missed, and that the relative positions of the observed workings as shown in figure 6 are in error. The highest working found is in thin-bedded graywacke and slate at an elevation of about 1,400 feet on a 0.3-to 2-foot-wide ,uartz vein that strikes N. 85' W. and dips 82' N. The vein is exposed along 15 feet of opencut in front of a caved edit. Slickensides plunge 20° N. 80' K. on the hanging wall of the vein. The vain is strongly iron stained and contains scattered irregular lenses and stringers of sulfides, principally areenopyrite and pyrite. A 1-foot channel sample (ACH-060) cut across a portion of the vein containing about S percent sulfides assayed 8.8 ppm gold. About 500 feet S. 70° W. and at an elevation of approximately 1,180 feet, quartz vein striking N. 85' w. and dipping 76' W. has been explored by a vertical shaft. The shaft is filled with water to within 1 or 2 feet of its collar but appears to be about 30 feet deep. The vein, Which cuts thin.-bedded graywacke and argillite striking N. 20' E. and dipping 30' NW., is exposed for a length of a,out 20 feet on it ranges between 1 and 2 feet in width and locally contains lenses of country rock within the quartz. A random channel sample (ACH-061) across 2 feet of vein, including some massive arsenopyrite, assayed 304 ppm gold, the highest gold value o:,tained during the investigation. A little more than 100 feet north and slightly higher, a second shaft, about 3 feet deep, has Jean dug on a vein, foot wide, that strikes N. 80° ';1. and dips vertically. Only minor amounts of sulfides were observed in vein material on a Troll dump by the shaft.

-CZ ATC SLary ~AAy4IACK6 /Y455/ g C.esykl ,46A-V- / / / tic* st44. 4 .4.11 /4 s.,4 Le' 0S.,4tLet SMAPLE ACK 04L. A. (1),..) 10,14k (44) Qvfet5t) S$'44; S =11.4. // 1., Vert, / All urtierirrundi / / Vey., O.'S­ 3-101. Sv1411.' rk4,t co,ue1 eopTal f. t, a0.,fi —7 , rtila Vn.. I-2' 5-1,/. s.1414.s SArAtLF ACA- 041 Au. (pt,,) Figure too 2-00 1-af CO.. foot vo.i too .f4. ( fr.." Se ld.JlL C 7.4.4...A le..) Sketch map of geology and mine workings at locality Nuka Bay area, Alaska 81)/ . ar , arr auJ d ,ft .4 6.41..1

S1J V1k.4 ae d dtp 4 Jet, D'ct tnei quavii? vt Plu`si. `51,. al WO S Jev-tcal cite4c.T16,.. and -wok sc- 1,1 01.4 Q chta. Jan. Ll 0167 Ma? fr.,.. pact Ciaa1 Co...Tass t

Three hundred feet N. 60' W. of the deeper Shaft and at an elevation of approximately 1,120 feet is the portal of an exploration adit with about 410 feet of underground workings. The edit has been driven on an irregular easterly trend for about 270 feet, at which point it splits into two southerly directed segments. All of the workings are in thick-bedded dense graywacke locally containing inclusions of black argillita. About 20 feet in from the portal, a quartz vein 0.5 foot wide, has been followed for 30 feet. At 65 feet from the portal a second and somewhat wider quartz vein dipping 86' S. has been followed for almost 80 feet. This larger vein appears to end in a stockwork of oartz 160 feet in from the portal. Neither vein contains any appreciable amount of sulfide mine,:als; a 1-foot channel sample (ACH-062) across the larger vein assayed 0.8 ppm gold. The adit was undoubtedly driven to intersect the veins exposed on the surface, but, as indicated by the sketch map (fig. 6), the tunnel was not of sufficient length to intersect the vein exposed in the deep shaft, and the vein in the shallow shaft apparently does not extend down to the edit level. Locality 5 (Charles Frank prospect) A caved edit a few feet above high-tide level on the west shore of North Arm about 1.8 miles from Moss Point is all that can be seen on the former Charles Frank property. According to Pilgrim (1933, p. 40) the adit was driven to intersect two 4uartz bodies exposed 40 feet higher on the steep hill slope, but which are now covered by slide de',ris and vegetation. Pilgrim (1933, p. 40) describes the adit as extending N. 50' W. for 60 feet Where it encountered a quartz vein 8 to 14 inches wide, trending N. 52° E. and dipping 79' N. The vain was explored t'y a drift 8 feet to the southwest and 43 feet to the northeast. All of the workings are in black slate. At the caved portal of the edit, foliation in the black slate trends N. 25' B. and dips 35' NW. On the small dump a few pieces of vein l uartz with minor arsenopyrite were found; a grab sample (ACH-050) assayed 0.04 ppm gold. Locality 6 (Rosness and Larson mine) In a small cove 0.2 mile north of locality 5 are the mine workings and ruined mill and camp buildings of the former Holiness and Larson mine. According to Pilgrim (1933, p. 41) the mine apparently produced some gold during the period 1931-1933, ;Alt by 1936, when Capps visited the area, the property was inactive (Smith, 1938, p. 32). On the southwest shore of the cove, across a small stream from the mill, a 30-foot-long edit with a water-filled wine at the end follows a atockwork of parallel quartz veins in thin-bedded graywacke. The veins, which range from 0.1 to 0.5 foot in width, strike N. 30° w. and dip 67' S. following the bedding of the graywacke. A composite sample (ACH-052) across four of the veins assayed 26 ppm gold.

Two hundred feet to the northwest, just above the mill at an elevation of about 50 fast, is a caved edit with vein quartz, containing minor arsenopyrite and pyrite, on the dump. Selected samples (AIMI-051) of this material assayed 0.05 ppm gold. This adit may be the 20-foot edit at an elevation of 110 feet referred to by Pilgrim (1933, p. 42) Which was driven on a quartz vein trending east-west and dipping 80' S. Slightly higher on the hillside and about 100 feet north of the caved edit is an opencut, now covered with vegetation, that according to Pilgrim (1933, p. 42) exposed a zone of brecciated graywacke containing many stringers of quartz striking N. 58' W. and dipping 80' S. Below the remains of this cut, a few feet above high-tide level, is an edit about 120 feet long which had been driven N. 70' W. apparently to intersect the veins exposed on the surface above. The edit is entirely in black slate with minor interbedded graywacke; no mineralization was observed. A few hundred feet north of the mine workings on the north side of the cove are three light-colored pyritized dikes that trend N. 20' W. and dip steeply to the southwest. Prom west to east the dikes are 0.4.0w 42v approximately 20, 15, and 2 feet wide These dikes are apparently the same granitic dikes described by Grant and Higgins (1910, p. 174) and on which a mining claim had been staked prior to their visit in 1909. Locality 7 (Robert Hatcher prospects) On the west side of North Arm just south of the entrance to Pilot Harbor, two old edits were found that were driven by Robert Hatcher about 1930. Both edits are on the steep rocky shore just at high-tide level, and at the time of our visit in June 1967, rough weter prevented a close examination and sampling of the veins. The first edit, just south of the entrance to Pilot Harbor, has been dug a few feat on the quartz vein 3-4 feet wide trending N. 70' V.. and dipping vertically. Pilgrim (1933, p. 44) mentions that visible free gold was found in surface exposures of this vein 170 feet above sea level. The country rock is interbedded graywacke, conglomerate, and black slate containing a number of small barren quartz veins and veinleta. About 0.15 mile south of this edit, a longer edit (possibly 20 feet in length) has been driven on a 2-to 3-foot quartz vein trending N. 80' W. and dipping 70' N. in conglomerate and graywacke. According to Pilgrim (1933, p. 42-43), Hatcher also worked on another vein (Utopia and North Gold claims) about 1 mile south of Pilot Harbor. He traced this vein by surface pits over the ridge into the Quartz Bay drainage(?). The vein reportedly strikes N. 75' w., dips 85* S., and ranges between 0..5 and 2.5 feet in width.

Locality 8 (Coyne prospect; Golden Horn mine) The former Goyne property is on the west shore of Surprise Bay about 0.6 mile south of the narrows into Palisade Lagoon. A wavedemolished cabin on a small slate-pebble beach, about 300 feet north of a still-conspicuous tailings dump, is all that remains in the campsite area. Exploration and development work at the prospect consists of two edits, approximately 25 and 135 feet above sea level, and a number of pits and trenches that have traced a series of mineralized quartz veins in a granodiorite dike from the bay to the top of the mountain ridge about 1,000 feet above sea level. Most of this exploration had been completed prior to 1934 (Pilgrim, 1933, p. 36-37; Smith, 1938, p. 30), and since that time the property appears to have Lain idle. Sometime after World War II, however, interest revived and an unsuccessful attempt to work the deposit was made by the Golden Horn group. At the time of our visit in June 1967, both edits were still open and accessible. Some effort was made to mains the surface workings above the edits, but the combination of heavy alder growth and steep hillside proved too discouraging. The country rock in the adit area is black slate that has .een intruded by a very irregular and locally segmented dike (fig. 7). Figure 7 near here Foliation (slaty cleavage) in the slate strikes N. 5° W. to N. 10' E. and dips vertically. Near the dike and especially between segments of the dike, however, the foliation is generally concordant with the slate-dike contact. The dike has a general east-west trend, dips 65'-85* S. and is 30 feet to probably as much as 100 feet thick. In hand specimen the dike is light gray and dense with a medium-grained equigranular texture (see page ). Quartz veins, in places containing abundant arsenopyrite, appear to be confined to the dike or 1-cally along the dike-slate contact. The veins are narrow and discontinuous and in general parallel the trend of the dike. Where a vein trends into the slate, it pinches out or splits into a number of thin quartz stringers that pinch out. In the underground workings, the principal vein encountered is exposed on both levels and al.ng a raise connecting the two levels (fig. 7). In the upper edit, this vein is about 70 feet long with a maximum width of 0.9 foot. It strikes N. 85' E. and dips 75° S. In the lower edit, about 110 feat Below, the vein is pro:.)a_dy ..L,out 100 feet long and has a maximum width of 1.1 feet. Two random channel samples across the vein indicate a fairly high gold content: 200 ppm gold across 0.9 foot in the upper edit (sample ACII-081) and 40 ppm gold across 1 foot in the lower adit (sample ACH-080).

SAMPLE ACH - 081 VC lY1 o - 0.1'

Zoo 4/14..1 N s.114..si 7.::;,s N. — Vein, 85' , 0- 5'/. lull het v .170' T6,.. o,u.. t3 vet ,sail 0...,,t, st.kw..kc \--k ..,_TI.,... she.. lo.. ii, sl..fe it co.Thet

.../m, .1.41.13- Velni.tt dive. , 0- 0.5* 40;41o.

Upper alit el. 135' is. . Q„„,t, ,37 / ve,,det — / 7' ---

"". ,

t Veins 0-0.1.' ,..4e.X i,, k 53 'I° N. // //AO' 50, /7­ ZO.1. 0- I. I' wi4t.. 0-io% Ai.., 0- 0.3' sutf.i 3.1f c, 45' si Bl4ck sl..te SAMPLE ACH - 080 (khd d +0 (un4ev-cti.f. vult.l, ad'f" s6/.4) ISO' a C61,1&et,IC P,OWk Urp,, i Upper 0.4;t d, r . Lowe,. alit. of Awd cvi'lcit Pl1/4""l'i1 00 skewL.1 or Utre., kt:Ct ti Low tr a dif So' Mi.,. 14,1 'kis Lower alit I° i To A B SECTION LOOKING, WEST Fro. And co.Kpiss svrvelb/ ,lune 2. 047 &At,. L.A eve.( Figure 7. Geologic map and section of mine workings at locality 8, Nuka Bay area, Alaska

A number of much smaller quartz veins are exposed in the two edits. Many of these are nothing more than slightly thickened lenses of quartz and at most contain less than 1 percent sulfides. Locality 9 (Sonny Fox Mining Company; Babcock and Downey property) The Sonny Fox mine, former principal gold producer in the Nuke Bay area, is on the west side of Babcock Creek about 0.9 mile N. 30' E. from the head of Palisade Lagoon at an elevation of 200 feet. A wellgraded trail extends to the mine camp from the Babcock Creek flat about 0.7 mile above the head of the lagoon, but the trail across the flat from the lagoon is no longer discernible. The quartz veins on the property were discovered in 1924; active mining and production began in 1926 and continued virtually without interruption until 1940 (Smith, 1938, p. 27; Smith, 1941, p. 25). In the main mine area, the gold lodes have been explored and mined three edits totaling more than 800 feet of underground workings and a number of opencuts and pits (see fig. 8). From the lower edit a rock and wood trestle extends south 1,000 feet to the mill, now almost completely ruined. About 250 feet southeast of the lower edit are the buildings of the camp, most of which are still standing and serviceable. Twelve hundred feet north of the mine, the small vein on which the original Sonny Fox discovery was made has been explored by 100 feet of tunnel on two levels and a 40-foot interconnecting raise (Pilgrim, 1933, p. 31). These workings were not examined during the present investigation. A sketch map of the geology and mine workings in the lain mine area is shown in figure 3. Three ,uartz veins have been explored in Figure 8 near here the immediate area but only one, the Lady Luck vein, was extensively mined. At the uppermost workings, at an elevation of approximately 225 feat, a large opencut exposes two veins about 2i feet apart in black slate. The westernmost vein is 3-4 feet wide, strikes N. 10° and dips 65.W. No sulfides were seen in the quartz, and a 4-foot Channel sample (ACH-084) revealed only 0.08 ppm gold. The other vein, which shows considerable iron staining, is 1-2 feet wide, strikes N. 750 E., and dips vertically. A 2-foot channel sample (ACH-085) assayed 0.1 ppm gold. From the face of the opencut an edit, filled co a depth of 1-2 feet with water, follows this vein for a distance of 60 feet Where it is cut off by a fault (Pilgrim, 1933, p. 32). This vein is also exposed in a small prospect pit about 40 feet east of the opencut, but in pits farther to the east only black slate is present.

Veir, I-2: ,uJe_. (SAMPLE Ac 4.085) Au (pep.) Iw,J t 1, (4+1 Vtin 3-4' ,,,,de. vis,b4 suii,ds Z' 4.5*/ S6s-llew protpejt pits 4.5* 4 Si 7 w,1i1, 44 ;14. tf 0. og Open ev+ A41;t 044e.- ZZS' 5+pli4 'Akk !SAMPLE qCH o8,31 svii.ie Adif el. 200' dum p CareJ el t so' Lilecl couere.i tram N St Glick stale. Roc.k r,,kt, loco i.et South .f psute. Sikt AnJ CLIP of foliate., ler Lie ie.& O Qukpi-3 Clevitions 6,1 iti+umeier Portal i- actin Ores, cut Pte, ?c.c.? pit flip {-Pow, ptce And comp,. ts tlet.tiet se 6 1 0.bi kictiTeR— Jv.e. 21,194.7 Figure 9. Sketch map of geology and mine workings at locality 9, Nuka Bay area, Alaska

About 200 feet south of the opencut and 25 feet lower in elevation is the edit which has been driven on the Lady Luck vein. The edit is accessible with difficulty for about 20 feet at which point a very irregular stope extending both up and down effectively bicks the way. In the edit, between the portal and the stope, the country rock is massive graymacke and no vein is exposed. Pilgrim (1933, p. 32) describes the vein and workings as follows: "Initial mining operations on the Lady Luck vain were conducted on the outcrop at the discovery point in an open-cut 65 feet in length from which several hundred tons of high-grade ore was extracted. (This opencut has evidently been covered by later mining operations.1 Subsequently, a tunnel 100 feet in length was driven on the vein below the outcrop exposure and at an elevation of 190 feet. At a point in this tunnel 40 feet from the portal a split in the vein occurs beyond which one branch of the vein strikes east and the other N. 4i' E. At an elevation 40 feet below this tunnel is the present main working tunnel. On July 25, 1931, it had been driven a distance of 230 feat on the vain and *toping operations were being conducted on the northeast branch of the vein between the working tunnel level and the upper tunnel." Later in 1936, Capps (in Smith, 1938, p. 27-23) reported: "The present workings are on a vein which crops out near the camp and on which more than 300 feet of drifts have been driven on two levels, in addition to raises and stopes. The vein has a general northeasterly strike and dip of a out &O' SE., though it varies considerably in both strike and dip within short distances. It ranges from 10 inches to feel in thickness and averages about 2 feet. The quartz is Lihite and locally shows handing. The most abundant metallic mineral is areenopyrite; some pyrite, sphalerite, chalcopyrite, and galena are also present. Free gold is also present, often in coarse particles abundantly visi.Le to the naked eye. The lower edit or main working tunnel, as mentioned above ,y Pilgrim, is caved at the edit and not accessible. It was driven into a cliff of massive graywecke that Shows no evidence of mineralization. Pilgrim (1933, p. 33) mentioned that where the vein is encountered the lower edit, it ranges in width from a few inches to 4 feet and is offset by immoral minor southeast-trending right-lateral faults. Locality 10 (Skinner prospect; Tidewater claim) The former Skinner prospect is on the steep rocky east shore of Surprise Bay, about 1 mile south of the narrows into Palisade Lagoon. A short edit, which was at sea level prior to the 1964 earth ueke, is now almost completely flooded during high tides.

The snit was driven sometine prior to 1931 .y Frank Skinner on a strongly iron stained quartz vein. In 1966 the property was relocated as the Tidewater claim y of Seward, Alaska. Slumping of the cliff at the portal of the adit has reduced its length from 42 to 25 feet 4'ilgri.7 1933, p. 30). The vein exposed by the edit strikes N. 80' E. and dips 72' S. It consists of about 0.5 foot of sheeted quartz with scattered lenses of arsenopyrite al ng the footwall and as much as 4 feet of ,r-r.2:1 quarts stockworks in the hanging wall. The country rock is lass'vy graywacke, Which along the hanging wall had been strongly brecciated prior to the introduction of the quarts stockworks. A channel sample (ACH-082) across the 0.5 foot of iron-stained quartz assayed 6, gold. Locality 11 A 4-foot-wide mineralized zone of vein quartz and fractured grayuucke in massive graywacke is exposed al,,ng the sea cliff in a small cove on the south side of the entrance to Beauty Bay. The structure strikes N. 80' E. and dips 70' S. (fig. 9). Iron-stained Figure 9 near here quartz containing lenses of arsenopyrite and pyrite ranging in width from 0., to 2 feet forms the footwell of the structure. The hanging wall consists principally of fractured graywacke and irregular, short, .,rancling veins of uartz. A 2-foot channel sample (ACH-049) across the widest part of the mineralized footwall assayed 0.62 ppw gold. Locality 12 About 0.3 stile north of locality 11 on the point east of Shelter Cove, a number of quartz veins are exposed in a cliff of graywacke. The largest and most mineralized (slight iron staining) of the veins strikes N. 80° E. and dips vertically (fig. 9). The vein is 2 feet wide with a thin clay gouge zone through its center and another along its north wall in contact with graywacke. A channel sample (ACH-048) across the entire vein assayed less than 0.02 ppm gold. Other prospects not found The Frank Long property described by Pilgrim (1933, p. 50-51) and the Skinner prospect described by Capps (in 901th, 1938, p. 31) are probably the same, although a number of discrepancies exist in regard to length of tunnels and orientation of the veins. This prospect is reportedly on the west shore of West Arm about 111 miles south of the entrance to Beauty Bay and directly opposite Beautiful Island (see pl. 1). Diligent search along the coastline in this area during our visit, however, failed to reveal any workings, buildings, or even significant mineralization.

Vei, S-fyuc+vr. N 6.'6; 7o'S SAMPLE ACk-1-04-9 ( be1J / N Se.:E 44:NvJ Au (PP"`) h( 4) .,. ) T-i+:1-/ ' (pi pACtyr

z 8 f eat

ir

—111k Veiti clux6-1-3 Sketcl, 0.4 Vein eXroSGJ Masstv e n-- wc (1,0ev-t+c. CtKi ?tir t Sfecp cWff loek',"/ SeofhwesTs f S Wife1. veipi exposed steep Vet.. ho Sytft/tS er-ftcat cliff lookiry Weser 1,1 e*O.0 Figure I . Sketch of veins at locality 11 (above) and locality 12 (below) , Nuka Bay area, Alaska

The prospect wes examined by territorial mining engineers in 1924, 1925, and 1931. Pilgrim (1933, p. 51), who made the last examination, reported: "About 10 feet above high tide a tunnel has been driven on a vein that outcrops in a small gulch. The direction of the tunnel, which is also the strike of the vein, is S. 45' W. The vein is a well-defined fissure filled with white quartz containing considerable graywacke breccia. Arsenopyrita is the only sulphide observed in the quartz. The vein varies from 6 to 24 inches in width al ng the full length of the tunnel, which is 88 feet. The walls are slaty graywacke with a cleavage striking S. 30' H. A cross-cut in the graymacke has been driven for 39 fest in the direction of N. 33' W. from a point 27 feet in the tunnel. A sample taken from a pile containing about 8 tons of vein quartz, at the mouth of the tunnel, assayed gold 0.38 oz, silver 0.30 oz per ton. A log cabin is situated on the hillside above the tunnel. There is also a frame house on a Leveled dump at the portal of the tunnel." In 1936 Capps (in Smith, 1938, p. 31) described the prospect as: developed by a 50-foot tunnel at the cabin, just above high tide level *which] follows a quartz vein in massive graywacke that strikes N. 20° W. and dips 75° SW. The vein, Which is actually a stockwork of branching quartz veinlets, strikes N. 35' W. and dips 65" SW. and shows from 4 inches to 2 feet of quartz. It carried considerable quantities of sulphides, chief of which is arsenopyrite, with lesser amounts of pyrite, sphalerits, and galena." Capp; also mentions another vein on the property, the Golden Goose vein, which is said to have been traced on the surface for a distance of 2,600 feet. In 1934 a 300-foot edit was driven on the vein at an elevation of 400 feet, and assays as high as 4 oz of gold to the ton have been reported.

The Johnson and Dagen property included a number of veins that apparently extended over the ridge from the bead of Surprise Bay to Quartz Bay. Pilgrim (1933, p. 34-35) describes the veins that were exposed by trenching in the gulch trending northwestward from the head of Surprise Bay near the mouth of Palisade Lagoon. The veins, all in measive graywecks, are exposed at elevations of 370, 900, and 1,000 feet. Principal mineralization is at the upper exposure where the vein has a width of 40 inches and strikes N. 62. E. A 28-inch sample assayed 0.98 oz of gold per ton (32 ppm). Between the two upper exposures of the main vein, Pilgrim also described three cross veins ranging in width from 2 to 4 feet and locally containing abu,dant sulfides that join, but do not cross, the main vein at right angles. Slide debris and (or) snow apparently covered these exposures at the time of our visit in June 1967. Many other veins have undoubtedly been prospected throughout the area, but since the days of active exploration, these have been covered by vegetation or rock debris. One area containing known mineralized quartz veins that was not examined during this investigation is Yalik Bay, which extends west of T:!est Arm opposite Harrington Point (pl. 1). Pilgrim (1933, p. 38-40) describes in detail the Sather prospects on the south side of Yalik Bay and also mentions the presence of mineralized veins on the north side of the bay. Geochemistry of stream sediments A total of 44 stream-sediment samples were collected throughout the area for trace-element analyses. Sediments fram each stream were also panned at the sample site and examined for fold, and the panned concentrate saved for future heavy-mineral study. The sediments collected for trace-element study were dried, screened to -80 mesh, and analyzed for gold and other elements in the mobile field Laboratory of the U.S. Geological Survey in Anchorage, Alaska. Gold was determined on a 10-gram sample by atomic absorption spectrophotometry, arsenic by colorimetric methods, and the remainder of the elements ,y semiquantitative emission spectrometry. The analytical results are listed in table 4 and shown graphically on the TABLE 4 NEAR HERE geochemical map in figure 10. Figure 10 near here

ft Stream Sediment Samples

0.02-0.07 ppm gold O 0.02 ppm gold Other apparent anomalous elements are shown by their chemical symbol. Data are from Table 4. g5t Mine, prospect or quartz veins referred to in text. Barren Quartz Veins Area of abundant barren quartz A 0.07 ppm gold veins. IA 0.02 ppm gold Note: All sample numbers prefixed O 2 11/es with letters ACH. Data are from Table 3. Figure 10. Geochemical map of Nuka Bay area, Kenai Peninsula, Alaska.

Table 4.--Semiquantitative spectrogrdphic and obemical ana.yses of stream-sediment sampler ,Parts per million. Analysts: Se,iguantitative spectrographic analyses, Arnold Farley, Jr.; atomic absorption (gold) and colorimetric (arsenic), W. L. Campbell, R. L. Miller, T. A. Roemer, and A. L. Meier. A, not detected. Number in parentheses under elements is lower limit of determination in ppm7 Sample Au-V Aad/ Ag B Ba Co Cr Cu Ni Pb Sb Zn nos. (0.02) (10) (0.5) (10) (20) (10) (10) (2) (2) (1o) (100) (5) (200) AcH-009 A a' A A ACH-011 A A A , 2tio0 ACH-014 A A ACH-016 A A

A ACH-018 A A A ACH-019 A A A A ACH-020 A A A ACH-022 A A A A ACH-025 A A 1,000 ACH-027 A A )0 A ACA-029 A A A A ACH-031 A A A ACH-055 A A A A ACH-055 A A A A A ACH-057 A A A A A A ACH-042 A A A ..CH-0,4 A 1,000 A ACH-045 A A 1,000 A ACH-047 A 8o 7o 1,000 , A ACH-055 A A A ACH-054 A A A A ACH-055 A A A A A ACH-056 A A A A A ACA-057 A A A A ACH-058 A A A ACH-063 A A A ACH-064 A A A ACA-065 A A A ACE-066 A A A A ACH-067 A A A A ACH-068 A A A ACE-069 A A A A ACH-070 A A 7o A A ACH-071 A 1,000 7o A ACH-072 A A A ACH-075 1,000 )0 A ACH-074 A A 1,000 )0 A ACH-07, A A 7o 5o A ACH-076 A A A ACH-077 A A ACH-078 A A A ACE-086 A e.5 loo A ACH-087 A <10 A ACH-088 <.5 1/Atomic absorption i/Colorimetric

Free gold was not observed in any of the panned concew:rates, ,ut gold was detected by atomic absorption in 12 of the 44 stream-sediment samples from the area (table 4 and fig. 10). In all >ut one sample containing detectable gold, the gold content was low, ranging .etween 0.02 and 0.07 ppm; the exception (sample ACH-088) contained 0.5 ppm gold. However, because of the particulate nature of the gold and the relatively small size of the original field sample (approximately 5 pounds for panned concentrate sample and to 1 pound for analytical sample), the gold values reported may not be representative. For example, the apparent lack of gold in all the panned concentrates and most of the analyzed samples aey only reflect the fortuitous Lack of a gold particle in the small sample collected. Conversely, the relatively high gold content of A06-088 may be attributable to the presence of one gold particle or even a slightly larger than average gold particle in the sample. Hence with the data available it is difficult to mimeses how much importance should be placed on either the lack of gold or its presence in a stream-sediment sample. Possibly a better indicator of the gold potential within a stream drainage is the arsenic content of the stream sediment. In this case, however, only two streams (samples ACA-037 and AC8-065) show arsenic values which could be considered anomalous, and these show no obvious relation to the gold content of the samples. Assuming, however, that the samples are representative and that the reported gold values reflect, at least ..fn a fair degree, the availability of gold within a stream drainage, sample ACE-088 with 0.5 ppm gold may be significant. This sediment sample was collected from Babcock Creek at the head of Palisade Lagoon at an elevation of approximately 400 feet (fig. 10). The drainage of Babcock Creek above the sample site covers an area of less than a square mile immediately northeast of the former Sonny Pox mine and is underlain principally massive graywacke (pl. 1). The combination of high gold values in the stream sediments, favorable host rock, and close proximity to the Largest known gold deposit in the area, suggests the presence of additional gold-bearing veins in the drainage area. No significant anomalies in the other trace elements of the stream sediments were detected. Copper appears to be slightly high in three samples (ACH-057, ACE-058, and ACH-073) and lead slightly high in one sample (ACH-011). One anomalously low sample (ACH-037) contains barely detectable amounts of most of the metallic elements except arsenic, which is relatively high.

Conclusions and recommendations The lode-gold deposits in the Nuke Bay area produced approximately $166,000 during the period 1924-1940. The gold is chiefly free milling and occurs with areenopyrite and minor amounts of base metal sulfides in short, discontinuous quartz veins and quartz stockworks. The more productive veins are confined to massive graywacke beds in a thick interbedded slate and graywacke assemblage of Cretaceous age and in thin granodiorite dikes. Most of the veins strike between east-west and N. 10' W., approximately normal to the structural grain of the folded sedimentary rocks. Sampling of the ivarts veins indicates the presence of high-grade gold values (aa much as 9 :lee* per ton) in a number of the old mines and undeveloped pmspects throughout the area. However, the veins are narrow, rarely exceeding 5 feet in width, and gold values appear to be erratically distributed within the veins. The economics of developing and mining these deposits has not been investigated, but based on the apparent past successful performance of the area (especially prior to 1935 When gold was $20 per ounce) sad the recent renewed interest in small gold lodes, it appears that diligent small-scale mining may be economically feasible and further prospecting warranted. Targets for concentrated prospecting are the massive graywacke beds and granodiorite dikes; veins in these rocks that trend east-west and contain sulfides are especially favorable and should be carefully examined. The gold anomaly on upper Babcock Creek may be significant and should be investigated. References cited Grant, U. S., and Higgins, D. F., 1910, Preliminary report on the mineral resources of the southern pert of Kenai Peninsula: U.S. Geol. Survey Bull. 442-0, p, 166-178. Martin, G. C., Johnson, B. L., and Grunt, U. S., 1915, Geology and mineral resources of Kenai Peninsula, Alaska: U.S. Cool. Survey Bull. 5$7, 243 p. Miller, D. J., Payne, D. G., and Grye, George, 1959, Geology of possible petroleum provinces in Alaska, with an annotated bibliography by* N. Cobb: U.S. Geol. Survey lull. 1094, 131 p. Payne, T. G., 1955, Mieosoic and Cenozoic tectonic elements of Alaska: U.S. Geol. Barmy Misc. Geol. Inst. Map 1-84, scale 1:5,000,000. Pilgrim, E. R., 1933, is Stewart, B. D., Mining imeeetigations and mine inspection in Alaska, biennium ending March 31, 1933: Alaska Div. Mines and Mimerals, Smith, P. S., 1938, Mineral industry of Alaska in 1936: U.S. Geol. Survey Bull. 897-A, p. 1-107. 1939, Mineral industry of Alaska in 1938: U.S. Geol. Survey 5,u11. 917-A, p. 1-113. 1941, Mineral industry of Alaska in 1939: U.S. Geol. Survey Bull. 926-A, p. 1-106. 1942, Mineral industry of Alaska in 1940: U.S. Geol.Survey :;u11. 913-A, p. 1-102.

Williams, J. A., Director, 1959, Report of the Division of Minas and Minerals for the year 1959: Alaska Dept. Nat. Resources, 80 p. 1960, Division of Mines and Minerals Report for the year 1960: Alaska Dept. Nat. Resources, 88 p.

lot , : ° g beach deposits. dike ...r sit:. -bMassive graywacke. May include minor r- Kg interbedded slate. Interbedded slate, gravwd,ke, ,i1t4t. Ksg . and conglomerate. Includes minor lite and phyllite. Og fo is re:

(7rVii' , Qg V) sue Ksg Contact; approximate. Strike and dip of bedding, arrow indicates direction of tor ot bed. Strike of vertical bedding. Strike and dip of foliation. Strike of vertical foliation. Strike and dip of prominent joint. Overturned syncline showing tract. of axial plane and plunge whew. .nown. Minor fold showing plunge. Shear zone. Mine, prospect or quartz vein referr., to in text. Adit ,Jr, coNiOuR thltrINAL 103 ,E rr PLATE 1. GEOLOGIC MAP OF NUKA BAY AREA, KENAI PENINSULA, ALASKA Ba,

r

Geology by D. H. Richter, 1967

Usgs Library - Reston 1111111111111 001 3 1818 00082708 7

Plates & figures from the original