Mining developments in the Ketchikan and Wrangell mining districts. Lode mining in the Juneau gold belt. Gold placer mining in the Porcupine district. Water-power investigations in southeastern Alaska

Chapin, Theodore, Eakin, Henry Miner, Canfield, G. H. · 1918 · Report

Copper, gold, and silver produced in the Ketchikan mining district in 1915 and 1916. Year. 1915 1916 Ore mined. Tons. 50,997 76,111 Copper. Quantity. Pounds.

This 1918 document, Mining developments in the Ketchikan and Wrangell mining districts. Lode mining in the Juneau gold belt. Gold placer mining in the Porcupine district. Water-power investigations in southeastern Alaska, is preserved in the Mountain Man Mining Library for research and reference. Original source: pubs.usgs.gov.

MINING DEVELOPMENTS IN THE KETCHIKAN AND WRANGELL MINING DISTRICTS. By THEODORE CHAPIN. KETCHIKAN DISTRICT. INTRODUCTION. Mining operations in the Ketchikan district were conducted on a much larger scale during 1916 than in the preceding year, as is evident by the large increase in production. Seven copper mines were in operation, and the output of the larger mines was materially increased. Only two gold-lode mines were operated during a part of the year, but development work was continued on other gold-lode properties and a large quantity of gold was won from ores mined primarily for copper. Items of more than ordinary interest are the recent discovery of a lode of stibnite (antimony) ore, a mineral not known previously to occur in this region in commercial quantity, of lodes in which zinc appears to be the predominant metal, and of platinum and palladium in certain of the copper deposits. Interest in marble continues. At present production is confined to the quarries of the Vermont Marble Co. at Tokeen, but the district contains large bodies of high-grade marble, whose development awaits the capital necessary for their exploitation. Development work was continued on the barite claims on Lime Point, on Prince of Wales Island, and work was started on the construction of a treatment mill. The location of the known mineral deposits is shown on Plate V. LODE MINING. PRODUCTION. The increase in the production of 1916 over that of 1915 is shown in the subjoined table. The gold and silver produced were derived from both the gold lodes and the gold and silver bearing copper lodes. This increased production was due to the continued demand and high price of copper, which made possible the operation of a number of low-grade properties.

MINERAL RESOURCES OF ALASKA, 1916. Copper, gold, and silver produced in the Ketchikan mining district in 1915 and 1916. Year. 1915 1916 Ore mined. Tons. 50,997 76,111 Copper. Quantity. Pounds. 1,728,182 3,526,703 Valuer §302,431 867,569 Gold. Quantity. Fine oz. 1,727.38 2,769.61 Value. $35,708 57,253 Silver. Quantity. Fine oz. 11,666 19,361 Value.6 $5,914 12,640 Total value. ' 8344,053 937,462 a Computations based on average price ofcopper.in 1915 (S0.175) and 1916 ($0.246). b Computations based on average price of silver in 1915 ($0.507) and 1916 ($0.658). PRINCE OF WALES ISLAND. KASAAN BAY AND VICINITY. Kasaan Peninsula was again the center of the copper-mining activity of the Ketchikan district, owing in large part to the operations of the Granby Consolidated Mining, Smelting & Power Co. (Ltd.), which operates the Mamie and It mines. The Mamie mine was taken over by the Granby Co. in 1913, and development and improvements were started to put the mine into working condition. The aerial tram, which originally extended to the old smelter only, was rebuilt and extended to the dock in the harbor, where the ore is loaded on barges for shipment to the Granby smelter at Anyox, B. C. Mining operations consist of stoping the irregular-shaped ore bodies composed of chalcopyrite-bearing magnetite, associated with garnet, epidote, and other contact-metamorphic minerals, formed along the border of intrusive dioritic masses that invade limestone and arenaceous sediments. The Mamie continued operations throughout 1916, employing 55 to 85 men. Underground development work has been carried forward on all the levels, and on the lowest level ore bodies formed along porphyry dikes that cut the magnetite have been located. Considerable surface development work has also been done, with a view to locating new ore bodies. A topographic and geologic map has been completed, a magnetic survey has been made to determine the position of the magnetite bodies, and diamond-drill holes have been put down. The It mine was worked on about the usual scale, employing 25 men. The ore bodies occur along the contact of intrusive diorite and limestone, and are composed of chalcopyrite, pyrite, and associated metamorphic lime-silicate minerals but contain little magnetite. Development work in 1916 consisted in 5,000 feet of diamond drilling and the extension of drifts and raises on the 275-foot and 350-foot levels, from both of which ore was extracted. Operations at the Mount Andrew mine were started early in the year and carried forward on a larger scale than usual. The ore

U. 5. Geological Survey Bulletin 66E Plate V I V°. Z Are. Mbo Island

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WaterfiUl Cannery MAP OF THE KETCHIKAN MINING DISTRICT ALASKA SHOWING LOCATION OF MINERAL DEPOSITS Kanagunut BOUNDARY, Gold and silver Copper predominating Antimony Zinc predominating

British" Coltjmbta E Ntr

Zayaslj ) A/ Base from U. S. Coast and Geodetic Survey charts

DEVELOPMENTS IN KETCHIKAN AND WRANGELL DISTEICTS. bodies here are composed of very large masses of copper-bearing magnetite. The Goodro mine, near the head of Kasaan Bay, was operated, and a number of shipments of ore were made. The ore bodies are in gabbro, and the ore minerals are essentially bornite and chalcocite with lesser amounts of other copper sulphides. The ore also carries considerable gold and traces of platinum and palladium. . The ore is sorted by hand and trammed to the wharf, where it is loaded on barges for shipment to the smelter. The Rush & Brown mine, at the head of Kasaan Bay, was operated throughout the year, and shipments of ore were made. The mine is developed on two lodes, a contact deposit of copper-bearing magnetite and a shear-zone deposit carrying copper sulphides. Both of these deposits have been explored to the 250-foot level-by various underground workings. Besides these ore bodies of proved persistence and depth there are also a number of surface outcrops that have not yet been cut by the underground workings. A drift is now being driven along an underground slip on the 200-foot level to cut one of these ore.bodies, and surface showings near the ore bins are to be prospected by a stope now being opened from the glory hole on the sublevel above the 100-foot level. An incline now being sunk on the sulphide ore body will be used for a working shaft. South of Karta Bay and northwest of Twelvemile Arm, including the vicinity of Hollis, is a mineralized area in which gold lodes predominate. The country rock is a complex assemblage of sedimentary and igneous rocks whose relations have not been worked out in detail. The bedded rocks include tuff, breccia, schist, thin beds of limestone, black slate, argillite, and graywacke and are cut by a large boss of quartz diorite and associated porphyritic dikes. The lodes are quartz veins and occur in the intrusive and the bedded volcanic rocks as well as in the sediments. A number of claims have been located on Granite Mountain, in the quartz diorite. On the Last Chance group development was continued during the summer preparatory to putting in a stamp mill. The Ready Bullion mine and mill, near Hollis, were operated with good success. The mine is developed by three adits driven along the vein and connecting stopes. Development work was continued on the Crackerjack group of claims, adjoining the Ready Bullion, but no production was made. The Dunton mine, on Harris Creek, was not operated in 1916, but some prospecting and ore testing were done. The Burke and Lang claims were recently located on the north bank of Hollis Cove, about a mile northeast of Hollis. The lode as here exposed by surface stripping is a quartz vein about 20 feet wide, trending N. 70° W., parallel to the strike of the inclosing greenstone tuff country rock. Assessment work consisting of surface stripping

MINERAL RESOURCES OF ALASKA, 1916. was done on the Copper Hill claim, about a mile northwest of Hollis, a short distance from the Ready Bullion tram. The lode occupies a shear zone in greenstone tuff and is composed of a network of chalcopyrite veinlets inclosing sheared rock impregnated with particles of chalcopyrite and stained in places with copper carbonates. Both country rock and lode strike N. 70° W.; the greenstone tuff dips steeply northeast, -and the lode apparently dips in the opposite direction. McLEAN ARM AND MALLARD BAY. Prospecting and assessment work is being continued on a number of claims on McLean Arm and Mallard Bay. The country rock north of McLean Arm and part of that south of the arm is a medium-grained dioritic rock, evidently a part of the batholith that occupies a large area in the south end of Prince of Wales Island. South of the diorite is a narrow strip of greenstone with associated porphyritic alaskite. The diorite is intrusive into the greenstone. The light-colored porphyries are believed to be intrusive into both greenstone and diorite. The principal work has been done by Poison & Ickis on a group of claims extending from McLean Arm to 'Mallard. Bay, including mineral claims and a mill site. On the Veta a short adit with drifts and crosscuts has been run, and on the Apex and Adit about 200 feet of underground work has been done, besides a number of surface openings. The ore deposits occupy shear zones in both the greenstone and its associated porphyritic intrusives. Chalcopyrite is the principal ore mineral, with a little secondary malachite and in places a black coating that is probably chalcocite. The Apex, Adit, and Astor claims cover a mineralized zone that has been traced by surface cuts and underground workings for a distance of 300 feet across its strike. Within this zone are a number of well-defined lodes with intermediate parts which are more or less mineralized. On the Adit claim an adit has been driven for about 200 feet, exposing two well-defined parallel lodes and an intermediate area with disseminated chalcopyrite. The ore appears to follow very prominent fracture planes with a general trend of N. 20° E. and a southeasterly dip. The mineralization was not confined within these walls but extended into the wall rock. The adit follows one of the lodes for about 50 feet and cuts across to another lode. Above the adit, at an elevation of 550 feet, an open cut has been made on a quartz vein which appears to be the hanging wall of the lode. On the Veta claim the ore body occurs in the greenstone adjoining the diorite that forms the hanging wall of the lode. The lode strikes N. 45° W. and dips 70° NE. A short tunnel crosscuts the lode and drifts along it for about 20 feet. Adjoining the diorite is about 15 feet of greenstone mineralized with disseminated chalcopyrite.

DEVELOPMENTS IN KETCEIKAN AHD WRANGELL DISTRICTS. Below this low-grade ore is about 8 feet of high-grade chalcopyrite ore, which occurs in masses and irregular veins in the greenstone and also associated with quartz veins. The Spik claim is about a mile west of the Poison & Ickis claims and 2 miles south of the head of McLean Arm. It can be reached by a good trail from a point on McLean Arm half a mile west of the Poison & Ickis mill site. The developments consist of a few open cuts and a short adit. The country rock is greenstone with much intrusive granite. The ore exposed by the open cuts is of very high grade. It consists of bornite, chalcopyrite, and pyrrhotite, occurring in irregular masses in the greenstone. NICHOLS BAY. The rocks along the shore line of Nichols Bay are mineralized at a number of places, and several prospects have been located, but little work has been done on them. Near the mouth of the bay the Feickert claim has been located recently and a little surface stripping done. The country rock is red granite and quartz diorite. The lode is a chalcopyrite-bearing quartz vein about a foot wide. It strikes N. 50° E. and stands about vertical. Development work in 1916 consisted of surface stripping and the construction of a temporary shelter and blacksmith shop. Another Feickert claim has been located on the east side of the bay a short distance from the head. A trail leads from the cabins on the shore half a mile to the workings. The ore is chalcopyritebearing quartz, and the country rock is andesitic greenstone. The lode has been prospected by a shaft and other openings and traced on the surface by open cuts. The Alice claim, on the east shore of Nichols Bay, was recently relocated by Thornton & Kilpatrick. The country rock is andesitic greenstone with intercalated beds of limestone. The ore is chalcopyrite and occurs in the limestone in irregular bunches and veinlets. Two old shafts on the lode were filled with water at the time of visit and were not accessible for examination. A short distance north of the Alice claim is another property on which a little work has been done. The country rock is quartzite and siliceous slate interbedded with andesitic greenstone. The beds strike N. 20° E. and stand about vertical. The ore bodies consist of irregular masses of rock strongly impregnated with pyrite. No underground exposures were accessible when the property was visited. TAH BAY. Several-claims, including the Ranger 1 and 2, have been located recently in a mineralized area on the ridge southwest of Tah Bay, a small cove on the north shore of Hessa Peninsula, on the west coast

MINERAL RESOURCES OP ALASKA, 1916. of Prince of Wales Island. The claims, which are on a low ridge about 200 feet above sea level and a quarter of a mile from the beach, may be reached easily by trail. The country rock consists of greenstone tuff and red and green volcanic breccias and associated graywacke and green grits, which are well exposed along the southwest shore of Tah Bay. In the vicinity of the ore deposits the greenstone is cut by many granite dikes with associated quartz veins. The developments to date consist of one prospect adit about 10 feet long and a number of surface clearings to expose the outcrops. The largest outcrop noted is about 25 feet across and is concealed on all sides by vegetation. It is essentially magnetite, but in places carries considerable chalcopyrite. The numerous outcrops of magnetite cover a larger area, but the workings are as yet too meager to show the size of the ore bodies or the nature and extent of the copperbearing rock. HETTA INLET AND CORDOVA BAY. The principal producer on Hetta Inlet was the Jumbo mine, which was operated throughout the year on a large scale. The mine was leased from the Alaska Industrial Co. in November, 1915, by Charles A. Sulzer and since that time has been operated on this lease. A small sawmill has been erected on the beach south of the ore bunkers and supplies timber for mining and building. It is planned to move the town of Sulzer to the vicinity of the mine wharf. The Rex and Idela claims, recently located by Jack Smith and William Fox, are on the south slope of Green Monster Mountain at an elevation of 1,700 feet and may be reached by trail from the head of Cholmondeley Sound, a distance of about 5 miles. The developments consist of a number of open cuts and short adits which have exposed a mineralized zone for several hundred feet in an easterly direction. The ore bodies are lenses of chalcopyrite-bearing magnetite associated with masses of garnet-epidote-diopside rock along the contact of the limestone and intrusive quartz diorite. A little malachite also occurs. On the Rex claim a short adit has been driven into a body of magnetite-chalcopyrite rock inclosed between quartz diorite and limestone. The ore bodies, so far as could be judged by the few surface workings, are contact-metamorphic deposits similar in general character to the deposits on Copper Mountain. Deposits of zinc ore occur on the ridge about miles northeast of Sulzer. These deposits were not visited by the writer, and information regarding them was obtained from Mr. W. C. Waters. They occur at an elevation of about 2,000 feet on top of a low-ridge that extends westward from Beaver Mountain and divides the drainage of Portage Bay from that of Polk Inlet and Twelvemile Arm. The

DEVELOPMENTS IN KETCHIKAN AND WRANGELL DISTRICTS. country rock consists of crystalline limestone, black slate, and quartzite, which strike N. 70° W. and dip 70? NE. The limestone caps the ridge and appears to overlie the other rocks but is stratigraphically lower, its steep dip carrying it below the slate and quartzite. The ore deposits occur in limestone. Specimens of the ore examined by the writer consist essentially of zinc blende with a little galena in a limy matrix. The Lakeside claim, on the extreme south end of Sukkwan Island, is being developed by P. A. Tucker and Hal Gould. Underground developments in September, 1916, consisted of a vertical shaft 51 feet deep and a crosscut at this level 41 feet in length. The country rock is altered pyroxenite, a basic rock which is intrusive into the greenstone schists and associated schistose sediments. The greenstone schists are bedded tuffs and lava flows of andesitic composition with considerable secondary chlorite, epidote, and calcite. The pyroxenite, a rock originally composed essentially of pyroxene and olivine, has been altered to epidote, calcite, and serpentine. The greenstone schists, the sediments, and the altered pyroxenite are all cut by quartz diorite, a large boss of which occupies the rugged hills of the interior of the island. The schists and sediments strike N. 30° W. and dip southwest at steep angles. The ore deposits occur hi strongly mineralized shear zones along the contact of the pyroxenite and the greenstone, for the most part in the altered contact zone of the pyroxenite. Two such shear zones have been cut in the crosscut. One of these, in the southwest end of the crosscut, strikes N. 20° W. parallel to the strike of the country rock, but dips northeasterly. For a width of about 5 feet the pyroxenite is mineralized with disseminated chalcopyrite. The other shear zone is in the northeast end of the crosscut and lies along a vertical fault striking N. 20° W. It incloses about 2 feet of good chalcopyrite ore. No other development is in progress on Sukkwan Island, but at several places the schists show considerable pyrite mineralization. Harry Wills, representing the Alaska Tidewater Co., of Seattle, has located copper claims on the long peninsula east of Sukkwan Island,'a mile north of Lime Point, and plans active development in the near future. The claims are known as the Teresa and Florence. WEST COAST. Developments were continued at the Big Harbor mine, on Trocadero Bay, and a test shipment of ore was made. No notable production has ever been made from this mine, but development work has been in progress since 1908 and several shipments of ore have been made. The property was acquired in 1916 by W. W. Sweet, R. W. Sweet, and N. P. Olson, who have incorporated under the name Southeastern Alaska Copper Corporation.

MINERAL RESOURCES OF ALASKA, 1916. The ore body is a wide zone of silicified greenstone, within which are shear zones carrying lenses of rich chalcopyrite ore and stringer lodes. The country rock on the footwall of the lode is composed of altered calcareous and arenaceous sediments; on the hanging-wall side it is albite-bearing schist. The lode strikes N. 60° E. and dips 60° NW. The principal developments to date have been on three claims on the chalcopyrite lenses along the hanging wall of the lode. The ore bodies exposed in the workings on the Northland No. 1 claim were described in detail in a previous report.1 The developments on the Northland Nos. 2 and 3 claims consist of an adit and a connecting vertical shaft 120 feet deep, from which crosscuts have been extended at 28, 48, and 120 feet below the surface. The shaft for its entire depth is in ore consisting of pyrite and chalcopyrite. An adit 64 feet long connects with the shaft 28 feet below its mouth. This adit and a 10-foot crosscut beyond are all in ore, the lode material consisting of silicified greenstone singly mineralized with pyrite and chalcopyrite. A 20-foot crosscut on the 48-foot level was for 17 feet in pyrite-chalcopyrite ore and 3 feet in barren rock. On the 120-foot level an 18-foot crosscut shows 11 feet of pyrite-chalcopyrite rock and 7 feet of slightly mineralized rocks, but a drill hole in the face penetrates another body of sulphide rock. The workings at this place, known as the upper workings, appear to be on the same lode as the lower workings, for the ore bodies have been traced more or less continuously from the lower to the upper workings by outcrops of chalcopyrite-bearing rocks. The crosscuts at the upper workings, however, have not cut the hanging wall of the lode, so it would appear that the rich chalcopyrite lenses occurring along the hanging wall have not yet been opened and that the present workings are in the leaner part of the lode. It is planned to continue sinking at the upper workings to a depth of 500 feet and to crosscut every 50 feet. At the lower workings a raise to the surface will be completed and sinking continued to a depth of 250 feet, with crosscuts every 50 feet. BALL ISLAND. McLEOD BAY. A number of claims have been located on McLeod Bay, near the south end of Dall Island. Considerable development work has been done, including three adits and a number of open cuts and shafts besides several substantial buildings. The claims comprise several groups and include the Golden Chariot, Elks Pup, Elk, Daykoo, Delaware, No Name, Virginia, West Virginia, and others. The 1 Chapin, Theodore, Mining developments in southeastern Alaska: U. S. Geol. Survey Bull. 642, pp. 92-93,1916.

DEVELOPMENTS IN KETCHIKAN AND WEANGELL DISTRICTS. principal development work has been done on the Golden Chariot, West Virginia, and New York. This property is now controlled by W. D. McLeod and others. The footwall of the lode is massive crystalline limestone; the hanging wall is crystalline schist. Two well-defined ore bodies occur a strong vein of quartz ranging in thickness from 40 to 60 feet, and a parallel stringer lode, the two lodes with the intervening impregnated rock forming a mineralized zone from 200 to 600 feet wide. The country rock is crystalline limestone and siliceous schist and quartzite with a little greenstone schist. The beds strike N. 45° W. and dip 30°-45° NE. The quartz vein is the most conspicuous of the ore bodies. It has a general northwest strike, dips northeast, about parallel to the beds, and occupies the contact between the limestone and schist. It has been traced by workings and surface cuts for a number of claim lengths but is best exposed on the Elk claim by two adits and an open cut, which crosscut the vein in three places. Along the hanging wall there is a gouge seam about 3 feet thick, and a number of parallel seams of gouge occur on the hanging wall side of the vein. Gouge also occurs along the footwall. The quartz is rusty and brecciated and breaks down easily under the hammer. The vein is being developed for its gold content. The principal metallic, mineral is chalcopyrite, with lesser amounts of pyrite and galena. The very little gold that is visible is believed to occur in association with the sulphides. The stringer lode has not been extensively exploited. Several attempts have been made to open some of the rich stringers within it, but no systematic development of the lode as a whole has been made. On the beach claims on the southwest side of McLeod Bay this lode from the beach to the moss-covered area has a surface width of 400 feet and an actual width of 260 feet. This is a minimum width of the lode at this place, as it probably extends beneath the moss-covered area between the exposed part and the vein. At this place the lode is composed of quartzose schist, carrying several strong veins of quartz and innumerable stringers and gash veins. Both quartz and schist are metallized with chalcopyrite, pyrite, and galena. Particles of free gold occur sparingly, and individual stringers appear to be very rich. The schist is uniformly metallized with particles and tiny stringers of the sulphides. Attempts have been made to open some of the richer of the individual veins, but this method of mining will not prove satisfactory, for the veins are lenticular in habit and tend to pinch out both laterally and vertically. The lode, owing to its diffused mineralization over so great a width, lends itself much more readily to exploitation on a large scale and should be further investigated with this in view.

MINERAL RESOURCES OP ALASKA, 1916. The Lucky Strike claim is on the crest of Dall Island, at an elevation of 1,300 feet. It is 3 miles east of the head of Gooseneck Harbor, on the west coast, and 4 or 5 miles west of Sawmill Cove and may be reached by a trail starting from a point about 1J miles south of the entrance to Grace Harbor. The country rock consists of metamorphic schist, limestone schist and thin beds of limestone. The lode where not covered by vegetation appears to be a shear zone in the schist, mineralized with chalcopyrite, pyrite, and much limonitic material. It is cut by stringers of bluish quartz carrying bunches of pure chalcopyrite. The schist strikes east and is nearly vertical; the quartz stringers strike N. 20° E. and dip 60° SE. COCO HARBOR. The Silver Star claim is about three-quarters of a mile from the head of Coco Harbor, at an elevation of 1,700 feet. The dominant rocks between the prospect and the beach are crystalline limestone, greenstone schist, and black blocky schists. There are two parallel lodes having a general strike of N. 55° W. and a steep northeast dip, about parallel to the strike and dip of the inclosing limestone beds. The larger lode pinches and swells, ranging in width from a few inches to feet, and veinlets of the sulphides penetrate the wall rock, increasing in places the width of mineralized rock The visible contents are essentially sphalerite, chalcopyrite, and galena, with a relatively small amount of gangue. The other lode, about 30 feet northeast of this one, is of similar appearance and is composed of sphalerite, chalcopyrite, and galena. Assays made on a sample of this ore body showed notable amounts of gold, silver, zinc, lead, and copper. The underground workings consist of a 50-foot adit and two drifts. The adit was started on the outcrop of the main lode but apparently drifted away from it. Cabins have been built both at the claim and on the beach, and a good trail leads from the beach to the claim. The Shellhouse claims are half a mile northwest of the head of Coco Harbor, at an, elevation of 350 feet. A good trail leads from the cabin on the beach to the workings, which consist of an adit and a number of open cuts. The principal showings of ore are found in a large open cut above the adit. Samples taken from this open cut consist essentially of pyrrhotite and chalcopyrite. ANTIMONY LODE ON CAAMANO POINT. A lode of antimony ore was recently discovered on Caamano Point, the southern extremity of Cleveland Peninsula. The country rock is blue limestone intricately veined with calcite and quartz stringers and apparently interbedded with greenstone. The limestone beds strike N. 60° W. and dip 45° NE. The developments to date consist of a 12-foot shaft, a crosscut, and several open pits besides a

DEVELOPMENTS IN KETCHIKAN AND WRANGELL DISTBICTS. blacksmith shop and a short trail to the beach. The principal ore body exposed by the workings is a lode of solid stibnite ore about 3£ feet wide, trending N. 60° W., parallel to the strike of the limestone beds, and standing nearly vertical. Its length is not evident, but parallel to it are smaller bunches of stibnite ore, all occurring in a brown-stained limestone ledge. The ore is composed of bunches of solid stibnite (antimony sulphide) with yellow alteration products along the fractures. NONMETALLIC PRODUCTS. MARBLE. The marble quarry of the Vermont Marble Co. at Tokeen, on Marble Island, was operated on about the usual scale, employing 50 men. Assessment work was continued on the property of the Mission Marble Co., on Orr Island; on the Dickinson and Bell claims, on Carroll Inlet; and on the Marble Heart and associated groups, on the west coast of Dall Island, but no production was made. The marble deposits of southeastern Alaska are described in detail in a forthcoming Survey bulletin. 1 BARITE. Development work on the barite deposit on Lime Point, Prince of Wales Island, was continued in 1916 by a small crew of men, and a crushing plant near the Jumbo wharf was in process of construction. WRANGELL DISTRICT. WOEWODSKI ISLAND. The only productive mining in the Wrangell district in 1916 was at the Maid of Mexico mine, on Woewodski Island (fig. 1), from which a small test shipment of ore was made. The property consists of six claims, comprising the Maid of Mexico, Maid of Mexico South Extension, and Maid of Mexico North Extension Nos. 1, 2, and 3, situated on the border of Spear Lake, about 1J miles from the coast, at an elevation of 400 feet. This property is being developed on a vein of quartz carrying metallic sulphides and free gold. The country rock is greenstone schist with interbedded black slate cut by dikes of porphyry. The dominant strike is about east, with a steep dip to the south. The vein is about parallel to the inclosing country rock. It strikes from east to N. 60° E. and dips 60°-80° to the south and southeast. It follows the porphyry, in places lying between porphyry and black slate and in places penetrating the porphyry. The vein averages 4$ feet in width in Burchard, E. F., Marble resources of southeastern Alaska: U. S. Geol. Survey Bull. 682 (in preparation).

MINERAL RESOURCES OF ALASKA, 1916. the underground workings, but in the open cuts on the Maid of Mexico North Extension No. 1 it is much larger. Where the vein cuts the porphyry dikes it is wider and more irregular than where it lies between slate and porphyry. The quartz carries sphalerite, galena, pyrite, and chalcopyrite, and in places considerable visible gold. The walls are very clean, and the ore breaks away easily. A small parallel stringer occurs about 50 feet north of the main lode. South of the Maid of Mexico another lode has been cut on the adjoining Maid of Texas group of claims but has not been opened. FiGTOE 1. Map showing location of prospects in the vicinity of Wrangell. The principal work has been done on the Maid of Mexico claim. A crosscut adit 130 feet long cuts the vein 82 feet below the surface, and from this point a drift has been extended 20 feet to the-west and 150 feet to the east along the vein. The vein has also been exposed by surface trenching above the adit and drift and also by open pits on the Maid of Mexico North Extension No. 1 and a short adit on the boundary line between the two claims. MAINLAND. Assessment work was continued in 1916 at the properties in Ground Hog and Glacier basins. These properties are located 12 miles east of Wrangell, on the mainland, and may be reached by trail from the cabin at the mouth of Mill Creek to the foot of Mill

DEVELOPMENTS IN KETCHIKAN AND WRANGELL DISTRICTS. Lake, by boat across the lake a distance of 3 miles, and by trails from the head of the lake one trail leading to Glacier Basin and another along Porterfield Creek to Ground Hog Basin a distance of about 41 miles from the head of Mill Lake. The workings are at elevations of about 1,500 to 2,100 feet on the eastern branch of Porterfield Creek. Two ore bodies are being developed, one on each side of the creek. The country rock is argillite and crystalline schist composed essentially of quartz, feldspar, biotite, and hornblende, with accessory garnet, rutile, and pyrite. The general strike is northwest with steep dips northeast. The schist is cut by bodies of porphyritic quartz diorite and dikes of alaskite porphyry, a light-colored rock composed of quartz, orthoclase, and microcline with a little biotite and garnet as accessory minerals. South of the creek a 15-foot adit crosscuts a lode about 10 feet wide with a hanging wall of schist and a footwall of argillite. The lode carries galena and sphalerite. Along the hanging wall occurs about 20 inches of nearly solid galena. The remainder of the vein contains disseminated galena and sphalerite. Mineralization, was less pronounced toward the footwall, where the mineralized rock passes gradually into the slate country rock. Other workings are on the north side of the creek at an elevation of 2,100 feet and consist of open cuts and two adits, one 12 and one 160 feet in length. The ore bodies are inclosed in dense green crystalline schist cut by many porphyry dikes, .along which the lodes have been formed. Both country rock and lodes strike N. 45° W. and dip 63° NE. The best exposures are found in the ong adit, which trends N. 55° E., almost perpendicular to the strike of the country rock and the lode, and which cuts the lode about 70 feet from the portal. The lode as exposed in this opening has a stope length of 30 feet and a width nearly as great. It is diffusely mineralized with sphalerite, galena, and pyrite and contains lenses of nearly solid sulphide ore. Sulphide minerals with accompanying quartz stringers occur in the green schist near ftie face of the adit. About 100 feet above this opening there are a number of surface cuts and a short adit in the outcrop of the lode, which may be traced along the side of the gulch for a long distance by the wide zone of oxidized rocks. Development work was continued on the Berg property, on the mainland about 20 miles southeast of Wrangell. It is reported that an adit has been driven for 300 feet, and that work will be resumed in the spring.

LODE MINING IN THE JUNEAU GOLD BELT. By HENRY M. EAKIN. GENERAL SUMMARY. The progress of the mining industry in the Juneau gold belt (Pis. VI and VII) in 1916 was marked by the continued large-scale operation of most of the established plants, by the construction of larger reduction plants on properties of advanced development, and by the consolidation and enlargement of enterprise in the exploitation of properties hitherto but little developed. Advance was made in determining the extent and character of reserves in the several mines, in more specifically delineating mining difficulties that threaten safety or economy of operation, and in adapting systems of exploration and mining to overcome these difficulties. The Treadwell group of mines, on Douglas Island, carried on normal operations until August 1, when part of the stamp-mills were shut down to avoid further drawing of ore from beneath settling ground that threatened the safety of the Treadwell, Seven Hundred Foot, and Mexican'mines. The other properties continued operating as usual. Other activities on Douglas Island included assessment work on a number of different properties south of the Treadwell group and diamond-drill prospecting on the Tyee, Jersey, and Holman claims, north of Treadwell. On the mainland near Juneau the Alaska Gastineau and Alaska Juneau properties were in active operation, and development work was in progress on the Alaska Ebner property. Prospecting equivalent to the required assessment work was done on several other properties. North of Juneau along the gold belt the Eagle River, Jualin, and Kensington enterprises represented the chief activity. The EagTe River and Yankee Basin properties were consolidated early in the year, but no development work beyond the annual assessment work was done. The Jualin mine operated on a moderate scale throughout the year. The new project of developing and equipping the Kensington mine on a 500-ton daily basis was being rapidly executed in 1916, with a view to completion by the spring of 1917. South of Juneau only small-scale operations were carried on in 1916. The Alaska Gold Belt Co. did a little open-cut prospecting on its claims at the head of Grindstone Creek. At Taku Harbor several claims are still held. At Limestone Inlet Williams & Leak 103210° 18 Bull. 662 6

MINERAL RESOURCES OF ALASKA, 1916. installed a 5-stamp mill and tramway on their property and are reported to have milled some ore. Small operations at Snettisham are also reported. At Windham Bay a consolidation of properties with a view to larger enterprise in development had been made, and engineers were on the ground during the summer making examinations in the interests of prospective investors. West of Juneau, at Funter Bay, on Admiralty Island, four different properties are held, and assessment work for 1916 is reported to have been done on each. The ground of the Funter Bay Gold Mining Co. has passed into the ownership of a new concern, the Admiralty Alaska Gold Mining Co. The 10-stamp mill on this property, which had been run for several months testing ores, was shut down early in 1916, and development work was suspended pending financial arrangements for enlarged operations. DOUGLAS ISLAND. TREADWELL GROUP. The Treadwell group of mining companies, operating on Douglas Island, carried on mining and milling operations as usual for the first seven months of the year, treating 972,765 tons of ore, an average of 138,966 tons a month. Late in July signs of a subsidence of the hanging wall appeared at the surface near the boundary between the Treadwell and Seven-Hundred Foot claims, over the workings from which the main supply of ore was being drawn. To protect the mines from the dangers of further subsidence the heavy removal of this ore was discontinued August 1 and the 240-stamp mill and half the 300-stamp mill were shut down. The remaining 550 stamps continued normal operations for the rest of the year, treating 422,215 tons, or an average of 84,443 tons monthly, a deficiency of 54,523 tons a month compared with previous operations. The ore treated during the whole year aggregated 1,394,980 tons, with a total production of $2,466,936 worth of bullion. The following table gives the yearly gold production of the mines from the commencement of operations: Value of gold produced by Treadwell group of mines, Douglas Island. 1882-1884 $10,902 1885 280,479 1886 366,180 1887 476,934 1888 429,889 1889 652,490 1890 160,681 1891 769,765 1892 707,017 1893 694,658 1894 909,990 1895 852,585 1896 $1,028,691 1897 1,011,693 1898 1,010,235 1899 1,611,857 1900 2,081,840 1901 1,665,373 1902 2,223,373 1903 2,667,914 1904 2,845,994 1905 3,146,715 1906 3,085,324 1907 2,520,000 1908 $3,124,047 1909 3,534,871 1910 3,737,498 1911 4,983,474 1912 4,080,300 1913 3,904,066 1914 3,743,945 1915 3,228,066 1916 2,466,936 64,013, 782

U. S. GEOLOGICAL SURVEY BULLETIN 662 PLATE VI MAP OF THE NORTHERN PART OF THE JUNEAU GOLD BELT.

LODE MUTING IF JUNEAU GOLD BELT. The subsidence of the surface mentioned above has followed a series of cavings in the upper workings, which began as early as 1913. It has been accompanied by fissuring in the hanging wall and the appearance of a moderate flow of salt water on the 1,600-foot level. These phenomena constitute a menace that must be taken into account in further operations. 1 They affect the rate at which the broken and caved pillar ore can be safely drawn from the upper levels, and perhaps also the amount of this stock that can be finally utilized. Shrinkage in assay values of the material in the intermediate levels down almost to the 2,100-foot level has caused the abandonment of stopes that otherwise might have supplied the requisite ore for normal milling operations at the present time. As the levels below the 2,100-foot level, where the ore is of higher value, are not yet developed to the productive stage, the mill supply is curtailed to the point indicated by the operations after July 1. Consideration of the advantage of a unified system of operation of the Treadwell group of mines led to the appointment of a committee to determine a basis of consolidation. The report of this committee, which was submitted July 31, 1916, is in large part reproduced in the Mining and Scientific Press of August 26, 1916. It presents an exhaustive analysis of the past and possible future showing of the different properties, discusses geologic and mining conditions, gives the committee's findings with respect to an equitable basis for consolidation, and proposes a program for future development work. The plan of consolidation appears especially fortunate in view of the difficulties that have arisen to make the expensive work of deeper exploration and development imperative. The deeper development work was carried on rapidly during the year. The central shaft was completed for the 2,500 and 2,700 foot levels, and the combination shaft was being sunk to the 2,100-foot level. An incline was being sunk in the Mexican mine below the 2,100-foot level. These improvements will combine to give a complete service and ventilating outlet for the stopes on the 2,300, 2,500, and 2,700 foot levels. Diamond drilling below the 2,300-foot level was carried on in the Seven Hundred Foot mine, testing the ore body at least to the 2,700-foot level. A total of 14,383 feet of development work was done during the year on the entire group. By far the greater amount was done in the Seven Hundred Foot and Ready Bullion mines in developing the ore bodies in the lower levels. In both mines the reserves of ore in sight and broken ore were increased materially. The development work done in the Mexican mine during the first eight months of the year 1 Further caving and surface subsidence occurred Apr. 21, 1917, resulting in the complete flooding of the Treadwell, Seven Hundred Foot, and Mexican mines with sea water.

MINERAL RESOURCES OF ALASKA, 1916. was mainly on the 2,100-foot level. The later work was chiefly on the 2,300-foot level, where preparations for stoping are in progress. In the Treadwell mine development work was practically suspended after August. Earlier in the year considerable work had been done in opening prospective ore bodies on the 2,100 and 2,300 foot levels. MAINLAND. ALASKA GASTINEATJ MINING CO. The Alaska Gastineau Mining Co. is the operating company for the Alaska Gold Mines Co., whose properties comprise mineral lands in the Sheep and Gold creek basins, a mill site at the mouth of Sheep Creek, and water-power sites on Salmon and Annex creeks. The development of all these properties was completed in 1915, and operations were carried on throughout 1916 on a 6,000-ton daily basis. The advantages of abundant water power, modern facilities, and simplified methods of extraction have afforded the lowest cost of operation yet achieved in the region. Owing to the addition of waste from the' hanging wall of stopes on the higher levels the average tenor of the ores milled fell below the original estimate, and this has caused misgiving in some quarters regarding the ultimate success of the enterprise. However, the difficulties in the way of selective stoping were being overcome and the tenor of ores showed a gradual improvement month by month, promising soon to reach the desired grade. Smaller stopes than those originally opened are necessary to the production of cleaner ore from the mine. The expense of mining by this method will be greater, but it will be offset by the higher tenor of the ore supplied to the mill. As the levels in the 1,600-foot backing above the main adit are developed to the productive stage the capacity of the mine for producing a proper grade of ore will increase, and without doubt it can be kept equal to that of the present mill for a long period before resort to the reserves below the main adit level must be had. ALASKA JUNEATJ GOLD MINING CO. The Alaska Juneau Gold Mining Co. proceeded energetically throughout the year with the enlarged development of the mine and the construction of the new 8,000-ton mill. The main haulagewayfrom mine to mill was widened and equipped throughout with double tracks of 50-pound rails suitable for the traction of 10-ton ore cars, which are to be used exclusively in the enlarged plan of operations. The development of the north ore body was advanced by the completion of undercutting the great stope, 250 feet wide and 700 feet long, with the necessary ore ways, chambers, and gates, for drawing ore along both sides. Work pro-

U. S. GEOLOGICAL SURVEY BULLETIN 662 PLATE VII SERVOIR CREEKOAM MINING PROPERTIES 11. Alexander adit 12. Perseverance shaft 13. Groundhog 14. Ibex 15. Glacier 16..Silver Queen 17. Anderson 18.-Denny 19. McCartney 20. Goujd & Curry 1. Wagner 2. Boston 3. Goldstein 4. Hallam 5. Hallam adit 6. EbiTer adit 7. Humboldt 8. Ebner 9. Reilly 10. Alaska Juneau 21. Reagan 22. Dolan 23. Gold Belt '24. Jersey City 25. Treadwell. 26. Seven Hundred .-Foot 27. Mexican 28. Yakima 29. Ready Bullion 30. Alaska Treasure POWER HOUS& NO. I k ALASKA GASTINEAU

Map Showing Location Of Mining Properties In The Juneau District.

LODE MINING IN JUNEAU GOLD'BELT. ceecled also in driving raises and powder tunnels in the north ore body above the cut-out area, preparatory to the enforced caving of ore into the stope chamber as drawing proceeds. The south ore body was developed further by driving on working and prospect tunnels and by preparations for stoping selected bodies of proved ore. Although it is expected that the north body can furnish enough ore to supply the rated capacity of the mill, the development achieved on the south ore body makes it possible to supplement the output from this source whenever necessary. The construction of the mill went ahead steadily during the year. Late in autumn the housing had been completed and the installation of machinery and power plant was well advanced, with the expectation that all would be in readiness for operation early in the spring of 1917. The new mill uses jaw crushers to reduce the ore to 6-inch size; gyratory crushers for reduction to 3-inch size, and ball mills for the first phase of further reduction. Suitable grizzlies are provided so that all undersize is removed ahead of each crushing operation. That part of the ball-mill product going through 10-mesh screens is passed to roughing concentrators; the oversize from these screens is returned to tube mills for regrinding. Classifiers follow the roughers, the fines passing to the finishing tables and the oversize to tube mills for regrinding. Crushing and concentrating are the only operations in the process of ore reduction. The ball-mill practice is patterned closely after that of the Inspiration mill of Arizona. The 50-starnp .pilot mill was run at full capacity most of the year, treating a share of the ore produced in enlarging the mine. Its operation not only served to utilize the ore necessarily produced in drifting and opening stopes but gave practical tests of ores from the different workings and of methods of treatment. JTJALIN MINE. Operations at the Jualin mine were continued during 1916 on the reduced scale that was adopted at the beginning of the European war, owing to its foreign financial backing. However, there was a gradual increase in the extent of operations during the year, the force of 20 men employed at the start being increased to 65 by the latter part of the summer. The work is progressing on the plan of milling only the ore produced in developing the mine. No stoping is done, as the 10-stamp mill is fully supplied by the ore that is taken from the shafts and drifts that are being driven on the lodes. Although the mine is being developed into a larger producer more slowly than was originally planned, the present operations have the advantage of being self-supporting.

MINERAL RESOURCES OF ALASKA, 1916. According to Knopf i the work done prior to 1910 had developed three parallel veins, 75 feet apart, trending N. 40° W. and dipping 60° NE. to 90°. At that time the workings had reached, a depth of 200 feet below the adit level, which is 750 feet above the sea. The later development work has been directed mainly to the two outside veins. The workings have reached a depth of 310 feet below the adit level, and it is planned to extend them as rapidly as possible to 1,000 feet below the adit. The northeast vein has an average width of about 7$ feet, and the southwest vein of 5 feet, in the developed areas. The horizontal extent of the ore bodies in each vein is about 400 feet. The mine waters, which were formerly a hindrance to operations, are now fully controlled. They are collected on the 300-foot level and pumped to the surface at the rate of about 500 gallons a minute. The deeper development is planned so that the mine below the 300-foot level will be entirely dry. Control of the water has been achieved by additions to the pumping and power facilities. About 1,200 horsepower is developed by the hydroelectric plant on Johnson Creek in summer. In winter this is reduced to about 100 horsepower, and additional power is developed by internal-combustion engines as required. The plans for a larger mill are in abeyance pending a fuller development of the mine in depth. The ores in the upper workings are freemilling, so that ordinary amalgamating methods give a high recovery. In neighboring mines the ores change in character with depth, and a high extraction from the deeper ores is best obtained by flotation methods. The continued development of the mine on a moderate scale will give excellent opportunity for investigating the ores and designing the best equipment for their treatment. KENSINGTON MINE. After the consolidation of the Kensington, Bear, and Comet properties by the Hayden-Stone interests the combined development of the Kensington, Eureka, and Johnson lodes by a single adit tunnel was undertaken. This tunnel, known as the Kensington crosscut, was completed for a length of over 5,000 feet in 1914, and additional work was done in drifting on the different lodes. In 1915 only the necessary assessment work was done on the properties, but the reserves that had been developed were investigated further, and plans were matured for future development. These plans contemplated the exploitation of the known reserves with the least practicable expense for equipment and operation. The lodes were to be developed from the Kensington crosscut only; the mill was to be adapted to the use of flotation methods of extraction, with a daily 1 Knopf, Adolpb, Geology of the Berners Bay region, Alaska: U. S. Geol. Survey Bull. 446, p. 45,1911.

LODE MINING IN JUNEAU GOLD BELT. capacity of 500 tons; power was to be developed from streams without artificial water storage, and the scale of operations at different seasons was to be adjusted to the power available from this source at or above the rated capacity of the plant in summer and at a standstill for a part of the winter. The quarters and other housings on the properties were to be rehabilitated and enlarged as required, and proper rail connections between mine and mill were to be constructed. Active work on the execution of these plans was deferred until 1916, when it was begun with the expectation of completion early in the spring of 1917. The time schedule adopted for different phases of the work permitted the constant employment of a fairly uniform force of workmen. The wharves, buildings, railways, and trams, hydroelectric plant, milling plant, and concentrate storage and loading plant were to be completed in the order named, and productive operation was to begin May 1, 1917, on the completion of the mill. The progress that was reported late hi 1916 indicated that this time schedule was being met. The Kensington lode, which is fully developed above the adit level, is to furnish the main supply of ore for the first milling operations. The reserves in this part of the lode are said to exceed 500,000 tons. This plan will permit a gradual further exploration and development of the Johnson and Eureka lodes. The ore is to be stoped by the shrinkage method from levels 200 feet apart, and delivered to the main haulageway in the Kensington crosscut through an ore-way raise in the f ootwall. Tramways are to deliver the ore from stopes to the ore-way on each level. From the bottom of the ore-way the ore is to be drawn into cars and hauled by storage-battery locomotives to a 250-ton crib outside the portal of the Kensington crosscut. The ore is to be drawn from the crib into 6-ton skips operating on a 3-rail automatic reversible inclined tramway, delivering at a 150-ton hopper at the mill. The hopper bin will feed the ore by gravity to a gyratory crusher, giving a 3-inch product to be elevated to a 500-ton storage bin. Belt conveyors are to carry .the ore from the storage bin to ball mills, whose product first goes to equalizing tanks and then to flotation machines. The flotation product is then to be dewatered and loaded directly from the filter to 5-ton cars for haulage to the wharf tipple. Experimental work in the flotation of the Kensington ores shows that this method of treatment is far superior to the amalgamation process that was formerly used. Extractions of 92 per cent to over 97 per cent have been made, about 4 pounds of oil being used to the ton of pulp. Further experiments with a view of reducing the consumption of oil and power were in progress during 1916.

MINERAL RESOURCES OP ALASKA, 1916. FUNTER BAY, ADMIRALTY ISLAND. GEOGRAPHIC FEATURES. Funter Bay is formed by a reentrant in the east shore line of Chatham Strait about 10 miles south of Point Ketreat, the north extremity of Admiralty Island. It is 18 miles directly west of Juneau, but by water routes the distance is over 50 miles. The bay is about a mile wide and 2 miles long. The shore line is irregular, and the bay contains a number of small islands and reefs. There is a clear steamboat passage well into the head of the bay, and it forms an excellent harbor, with favorable sites for docks in many places. The shore of the bay is marked in most ol its extent by low sea cliffs, reaching 10 to 30 feet above sea level, back of which lie broad terraced tracts 50 to 200 feet above the sea. Half a mile from the shore line in most places the bay is encircled by mountains that rise very abruptly to various.altitudes up to 3,500 feet. The mountains approach nearer the shore line on both sides of the entrance. The lowlands at the head of the bay extend northeastward for several miles. The terraced lowlands and the mountain slopes are heavily timbered up to an altitude of 2,500 feet. The ground in the timbered areas is generally covered with moss and underbrush and above timber line with a heavy matted growth of shrubs and grasses, so that natural bedrock exposures are exceedingly rare away from the coast. Geologic study is therefore greatly assisted by the numerous open cuts, strippings, and tunnels that have been made on the mining properties during the 30 years that have elapsed since gold was first discovered here in 1887. The timber is largely of excellent quality spruce and cedar and far exceeds in amount any probable future requirements for mining purposes. The region has an abundant rainfall, so that the run-off is copious and fairly constant. The low elevation of the streams that gather on the terraced lowlands permits only a small amount of water power to be developed from them. There is, however, in the mountains south of the bay, a high hanging valley whose stream is said to be well adapted to large power development. GENERAL GEOLOGY. The rocks of the Funter Bay district include a highly altered bedded series, dominantly greenstone schist and subordinately limestone or marble, and a few small dikes of diabase, andesite, and diorite, which cut the bedded rocks at wide intervals. The schistose cleavage of the metamorphic rocks is generally parallel with the bedding planes. Locally intense crumpling and close folding on a small

LODE MINING IN JUNEAU GOLD BELT. scale are apparent, but in general the bedded rocks lie in broad and gentle folds. Over considerable areas both schistosity and bedding are near the horizontal. Joint systems on both large and small scales cut the bedded rocks at high angles with the schistosity and bedding or near the vertical. The major joint planes in places persist for hundreds and even for a thousand feet or more with great regularity in strike and dip. Such large fractures were probably accompanied by some differential movement between the blocks which they separate, but there is no definite indication of the maximum displacement. These planes are generally marked by quartz veins, which range in thickness, in the different individuals observed, from mere films to nearly 60 feet. At one locality four approximately parallel veins were measured in a section 330 feet across, whose thickness aggregated 90 feet. Obviously the introduction of this amount of quartz in a narrow section involved displacement of masses of the rock. T-shaped and L-shaped bends in some of the veins indicate differential movements amounting at least to the thickness of the veins. Other veins, which gradually thin out to their ends, do not have this significance. Faults later than the veins and offsetting them occur only here and there, according to present evidence. The metamorphism of the bedded rocks is for the most part of regional character and of earlier age than the igneous dikes or the quartz veins which are unsheared. Later metamorphic agencies have affected the bedded rocks locally, adjacent to the quartz veins, resulting in silicification and bleaching of the greenstone schists, accompanied by the introduction of sulphide minerals and in places of gold. Such minerals also occur in bands of greenstone schist without associated quartz veins at two localities, but they are not believed to represent a distinct period of mineralization. ECONOMIC GEOLOGY. The quartz veins and mineralized schists of the Funter Bay district are generally more or less auriferous, and since the time of the original discovery in 1887 several tracts have been held for mining purposes. The history of location, abandonment, and relocation of claims in the district is too tedious to narrate. The salient facts are that a great deal of prospecting and a little mining has been done, and at present four groups of claims are held, on only one of which development has advanced beyond the prospecting stage. These properties are the Portage group, the Seattle group, the Admiralty Alaska Gold Mining Co.'s holdings, and the Otterson claims.

MINERAL RESOURCES OF ALASKA, 1916. PORTAGE GROUP. The Portage group of claims are about 2 miles northeast of the head of Funter Bay, in a low, rolling timbered area. These claims are said to have been located about 1894, but little development work had been done prior to 1904, when Wright 1 visited the district. He describes the mineral deposits of the claims as follows: At the lower workings is an irregular vein apparently composed of a succession of lenticular quartz masses inclosed in slate. The strike of the lead corresponds with the northwest strike of the slaty structure, the dips being nearly vertical. The vein carries considerable pyrite and chalcopyrite with small amounts of galena, but assays are said to show that the ore is of low grade. A small shaft and open cuts expose the quartz at several points. Up the hill above these workings prospecting has been done on a belt of mineralized schist. This is exposed across a width of 30 feet and has a N. 10° W. strike and dip NE. 65°, the footwall being defined by an unmineralized and massive greenstone, the hanging wall by a gradual decrease in mineralization. Additional prospecting has been done on the property year by year up to the present time, measured by the amount of assessment work required to hold title. SEATTLE GROUP. A number of claims, known as the Seattle group, about 2 miles southeast of the Portage group, have been held for the last five or six years, and it is reported that considerable work has been done in prospecting them. The geology is similar to that of the Portage group, the prospects being mainly in mineralized schists. These rocks are apparently similar to the mineralized schists near'Youngs Bay, about 15 miles southeast of Funter Bay, and also to schists on Douglas Island, on the Yakima and Alaska Treasure properties. ADMIRALTY ALASKA GOLD MINING CO. LOCATION OF PROPERTY. The holdings of the Admiralty Alaska Gold Mining Co. comprise two groups of claims, including the earliest locations made in the district. The lower group is on the south shore of the bay halfway to its head and includes the Tellurium, Uncle Sam, King Bee, Lone Star, and other less important claims. The upper group is on the north slope of the mountains half a mile to a mile southeast of the shore claims. It includes the Patterson, Heckler, Washington, Mountain Queen, and other claims. (See PI. VI.) HISTORY OF DEVELOPMENT. The earlier history of this property is given by Wright 2 as follows: The first discoveries at Funter Bay were the Tellurium group, made in 1887 by R. Willoughby and C. Wier, of Juneau, but development in excess of the minimum 1 Wright, C. W., A reconnaissance of Admiralty Island: U. S. Geol. Survey Bull. 287, p. 150,1906. Idem, p. 149.

LODE MINING IN JUNEAU GOLD BELT. legal requirements was not begun until 1894. In that year a Huntington revolving mill and a Frue vanner were installed at the Tellurium mine in order to thoroughly sample the ore, and favorable returns were reported from this experiment. In the following year the Alaska Willoughby Mining Co. bonded the property and installed a 10-stamp mill with four Frue yanners. They continued operations in 1895-96 and later sold their properties to the Funter Bay Mining Co., which continued developments on many claims. The Funter Bay Mining. Co. held the property until 1904, when it was acquired through the courts by J. W. Hunter, who had done the assessment work, to satisfy his claims for wages. The property was bonded early in 1915 by W. S. Pekovich, who later incorporated the Admiralty Alaska Gold Mining Co., to which he assigned his interests. The mill installed by the Alaska Willoughby Mining Co. was used in 1895-96, when considerable ore from the Tellurium and Uncle Sam lodes was run. It was shut down before the Funter Bay Mining Co. acquired possession and remained idle until June, 1915, when Mr. Pekovich began operations. After a run of about eight months testing ores from the beach claims it was again shut down pending financial arrangements for enlarged operations. Except in these two short periods of productive operation little development in excess of the minimum legal requirements has been done on the property. The assessment work has consisted mainly in erratic prospecting, so that the properties are, on the whole, very poorly developed, considering that 30 years has passed since the original discovery was made. The Tellurium, Uncle Sam, and King Bee lodes have supported practically all the productive mining and are therefore the best developed. The Tellurium lode is developed by a drift 123 feet long, driven from the beach just above tide level. For most of this distance it has been stoped out to the surface through a backing of 25 to 30 feet and with an average width of 5 feet. The Uncle Sam lode is developed by a crosscut 98 feet long, leading from the mill to the vein, 228 feet of drifts, and about 1,000 feet of open-cut work. The vein is stoped out above the drift for 108 feet. A crosscut has been driven 70 feet on a fault plane about 200 feet from the mill crosscut, in the attempt to locate the offset portion of the vein underground. In the main drift 200 feet from the mill is a 30-foot winze sunk on a shoot of sulphide ore. The King Bee lode is developed by an adit 200 feet long, open surface cuts 20 to 25 feet deep at short intervals for a distance of 1,000 feet, a shaft 110 feet deep, and crosscuts at the bottom of the shaft 30 feet toward the Uncle Sam vein and 132 feet toward the Tellurium vein. The shaft collar is on the beach below high-tide level. The cribbing employed to keep out the sea water has been

MINERAL RESOURCES OF ALASKA, 1916. destroyed, and it is now flooded. The vein has been stoped out to the surface above the adit for most of its length. The other claims of the lower group are developed only by a few shallow surface pits. The claims of the upper group have been prospected mainly by surface pits and strippings, but a little underground work has been done on some of them. There is an 85-foot shaft on the Patterson lode, a 51-foot tunnel on the Washington lode, a 40-foot tunnel on the Devil Club lode, and three tunnels aggregating about 650 feet on neighboring claims whose names could not be learned. About 50 exposures in all, a few of which were natural exposures, the others open cuts or strippings, were examined by the writer on the upper group of claims. Although some of the work done on these claims may have been overlooked, it is believed that the list given represents very closely the extent of development thus far accomplished. Improvements on the property include the mill, bunk houses, shops, tramways, ditch lines, etc. The mill has its original equipment, consisting of ten 850-pound stamps, four Frue vanners, a 3-inch Huntington revolving mill, a 9 by 14 inch Blake crusher, suitable boilers, engines, compressor, water wheels, ore elevator, etc. Quarters are available for about 30 men. The shops include a wellequipped assay laboratory. Water is delivered to a penstock back of the mill by two ditches, one 5,000 feet long from the southwest and one 6,000 feet long from the northeast. A head of about 60 feet is developed. THE LODES. GENERAL FEATURES. The lodes that occur on the property of the Admiralty Alaska Gold Mining Co. are all quartz veins. The cleavage and apparent bedding of the schistose country rock are near the horizontal over most of the area, and the veins occupy fissures that cut across these structural features at high angles. Many .of the veins show great persistence in thickness and trend, and there is nowhere any suggestion of the bluntly lenticular form shown in the veins of the Portage group. Mineralization in the schists not directly associated with quartz veins is also lacking. It would appear that these differences are related to the structure of the bedrock encountered by the mineralizing solutions. In the Portage area the dips are high and the slaty and schistose structure afforded numerous channels for the upward passage of solutions, resulting in disseminated mineralization. In the Admiralty Alaska area, on the other hand, the only available channels were the stronger fissures cutting across the other features of the rock structure, along which the movement of solutions was definitely concentrated.

LODE MINING IN JUNBAU GOLD BELT. The introduction of the quartz veins was accompanied by local alteration of the adjacent schists. This action included silicification and the development of sericite and sulphide minerals. Some of the altered schists adjacent to the quartz .veins are said to give substantial assays for gold. The veins generally have a composite structure, as if they had gained their thickness by the addition of successive layers. The layers differ in color and mineral content in the same section and are generally separated in weathered exposures by a micaceous ironstained gouge. Layers relatively rich in sulphide minerals and metallic gold may occur in the same vein with layers that are almost barren. Pyrrhotite, pyrite, and galena are the most abundant sulphide minerals. Sphalerite occurs sparingly in places. Iron carbonate is abundant in some veins, especially in those that give the higher assays for gold. In these respects the mineralization in the Funter Bay district resembles that of lodes on the mainland near Juneau. LODES OP LOWER GROUP. There are three principal lodes on the lower group of claims whose characteristics have been revealed by development work. These are he Uncle Sam, King Bee, and Tellurium lodes, named in geographic order from southeast to northwest. The distance between the Uncle Sam and King Bee near the shore line is 100 feet, and between the King Bee and Tellurium about 700 feet. Near the beach the Uncle Sam vein strikes N. 55° E., the King Bee N. 60° E., and the Tellurium N. 65° E., so that their trends converge slightly to the northeast. A short distance from the beach the Uncle Sam vein turns to N. 65° E., and two parallel veins, not seen at the beach, appear southeast of the Uncle Sam at intervals of 10 and 20 feet. The Uncle Sam vein has a width in the mined section of 6 to 10 feet. Farther northeast, where exposed in open cuts, it is only 1 to 3 feet wide. The parallel veins noted above are 6 and 10 feet wide. The quartz of the Uncle Sam vein is of the milky variety, but it generally has a reddish aspect due to iron staining. Sulphide minerals, chlorite, and iron carbonate occur irregularly through its mass, finely disseminated in some places and segregated into irregular patches in others. A shoot of sulphide ore occurred in the vein about 100 feet from the mill crosscut, standing nearly vertical, about 8 feet across at the drift level and pinching downward for 30 feet. A shipment of 22 tons of ore taken from the shoot and sent directly to the smelter is said to have yielded $134 a ton in gold. The gold occurs mainly with the sulphides throughout the vein, so that the tenor of the ore can be estimated from its appearance.

MINERAL RESOURCES OF ALASKA, 1916. The King Bee vein is similar to the Uncle Sam in appearance and size but appears to hold its width more uniformly back from the beach. It is said to persist in size and gold tenor to the bottom of the 110-foot shaft. This lode supplied a large part of the ore milled by the Alaska Willoughby Mining Co. and is probably the most promising of all the lower lodes for future development. The Tellurium lode is said to be 10 feet wide in the beach cropping, which is now covered by shingle. It pinches gradually back from the beach and at the face of the 123-foot drift is only a few inches wide. Sulphide minerals, chiefly pyrrhotite, are abundant in the vein matter and along the walls. Calcite and iron carbonate also occur as gangue minerals. The ore mined from this ledge is said to have had the highest average value found in all the workings. The other veins exposed on these claims have been but little developed, a fact which may indicate that they are relatively lean. A white quartz vein about 6 feet wide near the Tellurium examined by the writer showed no sulphide minerals except a little sphalerite and on assay gave not even a trace of gold. The veins southeast of the Uncle Sam contain no visible sulphides in the surface croppings. As the property now stands there is little ore in sight above tide level in the lodes of the lower.group of claims. The backing of most of the drifts has been mined out, so that future development must look to the extension of the veins below tide level. Any project for their development must include plans for pumping not only the surface waters, which now enter through the long open cuts, but also more or less sea water that will seep in along the veins. Surface waters are known to sink along the veins in places and probably reach the sea through underground crevices. This flow would undoubtedly be reversed if lower levels were opened in the mines. The extent and availability of the lodes below sea level will be known only after much systematic prospecting has been done. It would appear that diamond drilling could be used advantageously in testing veins adjacent to the one that may be chosen for the first development work at depth. LODES OF UPPER GROUP. A large number of distinct veins were examined by the writer in the area of the upper group of claims, which lie on the steep northerly mountain slope half a mile to a mile southeast of the lower group. It is likely that not all existing exposures were found and also that there are many veins that have no visible croppings. Enough was seen, however, to show that veins on these claims are more numerous and much larger than those nearer the coast. In working without an adequate base map it was impossible to show the positions of the veins examined or to learn the names of the claims on which many of them were located.

LODE MINING IN JUNEAU GOLD BELT. The most development work has been done on the Patterson and Heckler claims. The Patterson claims are about a mile southeast of the mill; the Heckler claims he east of them. Veins are developed on the Patterson claims at two places; at one by an 80-foot shaft and at the other by an open cut. The shaft is sunk on a 6-foot vein containing sulphides and bordered by bleached schists that are strongly mineralized. The open cut crosses four veins aggregating 6 feet of quartz in a width of 16 feet. The main veins consist of milky quartz, but in places bodies of bluish translucent quartz containing albite crystals as much as half an inch in length project from them out into the schists along the structure planes. Both types of quartz are said to be gold bearing. On the Heckler claims, at an elevation of 1,700 feet, a stripping shows a quartz vein 57 feet across. The section northeast of this cropping along the hillside includes three other veins, two of them 10 feet and the other 12 feet wide, giving an aggregate of 89 feet of quartz within a space of 330 feet. The 57-foot vein is said to be ore; the other veins are not known to have been sampled. But little mineralization is apparent in any of these veins. At an elevation of 1,360 feet on the Heckler property, directly down the slope from the exposures just described, is the outcropping of the so-called Heckler blanket vein. The vein strikes N. 45° E. and dips 60° NW., conforming with the slope of the hill. It is 3£ to 5 feet thick and has an overburden of bleached mineralized schist 6 feet thick. The vein has been stripped for 90 feet down, the slope, over a width of 30 feet. It shows a very pronounced laminated structure. Some laminae are very rich in sulphide minerals and iron carbonate. A layer a few inches thick near the hanging wall contains visible gold and the whole vein is said to give especially high assays for gold. Weathering of the sulphides and iron carbonate has produced large quantities of iron oxide, which fills crevices between the more distinct laminae and also numerous vugs that are lined with quartz crystals. Southwest of the "blanket vein," at an elevation of 900 feet, a 200-foot tunnel has been driven on a 6-inch vein. The tunnel is said to have been planned to undercut some of the larger veins of the property about 700 feet from the portal. The 6-inch vein is made up of several laminae with margins of interlocking quartz crystals. It is rich in pyrrhotite, pyrite, and iron carbonate, and where weathered all crevices and vugs are filled with iron oxide. It is said to have a high gold tenor. The vein persists with even thickness and structure for the whole length of the tunnel and is exposed at intervals on the slope above the tunnel for several hundred feet. In some of the higher exposures it contains arsenopyrite and pyrrhotite.

MINERAL RESOURCES OP ALASKA, 1916. Many other veins, 2 to 10 feet thick and trending in various directions, were examined in natural outcrops, open cuts, strippings, and short tunnels in the course of the traverse over the upper group of claims. Their abundance and complex structure indicate that the bedrock over an area of a square mile or more is intricately seamed with intersecting quartz veins of minable size. Evidence of more or less mineralization is generally apparent, though there are croppings here and there without visible sulphide minerals. The first requirement for further development of the property is an accurate base map, on which the veins may be plotted. Then systematic prospecting and assay work should be employed to determine the extent and relations of valuable lodes and also the best scheme of exploitation. OTTERSON CLAIMS. The Otterson claims are southwest of the upper group of the Admiralty Alaska property, in a corresponding topographic position. They were not seen by the writer, but it was learned that the general aspect of the lodes is similar to those of the property to the northeast. They are said to be well-defined quartz veins 20 feet or less in width, in which gold is associated with sulphide minerals. Specimens from some of them show visible gold embedded in quartz and in pyrrhotite patches in the quartz. Prospecting work was in progress on the property in the summer of 1916.

GOLD PLACER MINING IN THE PORCUPINE DISTRICT. By HENRY M. EAKIN. INTRODUCTION. The Porcupine gold-placer district includes an area drained by westerly headwater tributaries of Chilkat River that centers about 40 miles northwest of Haines, a.small town on the shore of Lynn Canal, 75 miles north of Juneau. Placer gold is known to occur in the basins of four tributaries of the Chilkat, which, named in order from north to south, are Bear Creek and Klehini, Salmon, and Takhin rivers. The original discovery in 1898 was made on tributaries of Klehini River which have since been the chief source of production. The other basins have witnessed more or less prospecting and desultory development work, but they have contributed little to the output of the district. For several years mining operations in the district have been confined to Porcupine and Glacier creeks, which are southerly tributaries of Klehini River, 12 and 14 miles respectively from its mouth. The region was first visited by a Geological Survey party in 1899, when an exploratory expedition passed through it on the way from Pyramid Harbor to Eagle. 1 In 1903 C. W. Wright, of the Survey, spent three weeks in further examination of the district, and the results of his studies were published the following year.2 The writer visited the district early in the summer of 1916, spending two weeks in the examination of properties now under development and in the study of bedrock and glacial geology related to the formation of the plaeer deposits. The publications of the earlier investigations have been freely consulted in assembling the matter of this paper. TOPOGRAPHY. The region lies within the coastal mountain province of southeastern Alaska and partakes of its general characteristics of strong relief and glacially developed forms. Summit elevations along the principal divides generally range between 3,000 and 5,000 feet, but 1 Brooks, A. H., A reconnaissance from Pyramid Harbor to Eagle City, Alaska: U. S. Geol. Survey Twenty-first Ann. Kept., pt. 2, pp. 374-376,1900. 2 Wright, C. W., The Porcupine placer district, Alaska: U. S. Geol. Survey Bull. 236,1904. 103210° 18 Bull. 662 7

MINERAL RESOURCES OF ALASKA, 1916. individual peaks rise 6,000 to 7,500 feet above sea level. The main valleys are broad and steep sided and are floored by heavy gravel deposits of glacial streams. The topography has a smoothed aspect up to an altitude of about 3,000 feet, marking the level reached by ice during earlier periods of glaciation. Glaciers of considerable size still persist on the headwaters of the streams that drain the higher divides. ERO SIGNAL HISTORY. During the period of more extensive glaciation of the region both trunk and tributary valleys were deeply scoured by ice action, but the main valleys were generally lowered below the levels of their tributaries, which thus became hanging valleys. When the ice had retreated the streams from the hanging valleys found abrupt declivities in their courses at the margins of the main valleys. These conditions favored the erosion of canyons in tributary valleys and the deposition of detritus in the form of alluvial fans along the margins of the main valleys. These features are well illustrated in the present canyons and alluvial fans of Glacier and Porcupine creeks. In places in the Porcupine Valley at the side of the present canyon there are so-called bench deposits. These consist of stream gravels overlain by glacial detritus. It is evident that these deposits occupy sections of a canyon, older than the present one but due to similar processes, which was in some places followed and in others missed by the course of Porcupine Creek when the last intrenchment began. Two distinct ice advances are thus indicated, each of which was followed by intrenchment of the hanging-valley streams. The modern canyon has been eroded to a lower level than the earlier one throughout the middle and upper sections of Porcupine Valley. Near the lower end of the valley the conditions are not so simple, and it seems likely that the stream accomplished considerable intrenchment. along more than two courses. The identity and relations of the different bedrock canyons at this place could not be fully deciphered from the available exposures. It is clear, however, that the Porcupine was controlled by a lower base-level than that afforded by the present position of Klehini River at the time of maximum intrenchment in each position. In Glacier Creek valley also there is evidence of two distinct ice advances, with an intervening period of stream erosion. An extremely deep and narrow bedrock gorge filled with glacial detritus has been traced for some distance along the lower part of the valley beneath the modern stream gravels. A base-level of erosion much lower than the present is indicated, the same as in the lower Porcupine Valley. The upstream extension of this older canyon is not now eyi-

U. S. GEOLOGICAL SURVEY BULLETIN 662 PLATE VIII LEGEND Drainage from maps prepared by International- Boundary Commission Geol 10 MILES weoiogy by IU M l LC.3 C.W. Weight, 1904 andH.M.Eakin,l9l6 MAP SHOWING ECONOMIC GEOLOGY IN THE VICINITY OF PORCUPINE.

GOLD PLACER MINING IN PORCUPINE DISTRICT. dent. It may have been destroyed by later ice erosion in Glacier Creek valley or it may have been followed by the stream in its last intrenchment. The narrowness of the valley favors the latter interpretation. PLACERS. The concentration of placer gold took place in conjunction with the intrenchment of the hanging-valley streams wherever their courses traversed zones of mineralized bedrock. The placers are therefore of two distinct ages, corresponding with the separate periods of stream erosion. The concentrations are generally found in a thin stratum of stream gravels lying on the bedrock bottoms of the canyons. Locally, as below the falls on McKinley Creek, gold has been found on bare bedrock practically without associated gravels. The gold-bearing stratum is generally overlain by barren or very low grade gravels that are progressively deeper downstream. The stream gravels in the bottoms of the older canyons, which are gold bearing in places, are overlain by glacial detritus whose depth is generally measured by the height of the canyon walls. In the lower section of Glacier Creek modern gravels overlie the glacial fill of the older canyon, which extends to a great depth below the present stream and has a much steeper grade. At the lower ends of the modern canyons, where the alluvial fans begin, there are certain concentrated deposits that extend into the gravels somewhat above bedrock. They are less regular in form and of lower grade than the gravels within the confines of the canyons and.extend but a short distance out into the Klehini Valley. Apparently the alluvial fans are devoid of notably concentrated placer deposits except possibly at their very heads. GEOLOGY. The solid rocks of the district consist mainly of metamorphosed sedimentary types, including limestones, slates, phyllites, and schists. The schists are apparently developed only locally through excessive alteration of beds that are generally represented by slates and phyllites. Likewise silicification of limestone has produced quartzitic beds in small areas. The general area of sedimentary rocks is bordered on the northeast by the great belt of diorite that extends southeastward in the Coast Range. Outlying masses of diorite are intruded into the sedimentary rocks for some distance southwest of the principal contact. The general distribution of these rocks is indicated on the geologic map (PI. VIII), which is reproduced, with slight corrections, from a map drawn by Wright.1 1 Wright, C. W., The Porcupine placer district, Alaska: U. S. Geol. Survey Bull. 236, pi. 5,1904.

MINERAL RESOURCES OF ALASKA, 1&16. j The structure of the sedimentary rocks has not bem worked out in detail, but the observations that have been made indicate that it

is exceedingly complex. The beds are steeply tilted wherever ob- ( served, dips of 75 to 90° being common. The apparent trend of the , great limestone band that crosses the lower courses of Glacier and Porcupine creeks is northwesterly. The limestones of the Klehini J Valley above Jarvis Creek also strike northwest, and this is the direc- ,: tion of the larger igneous bodies of the region. However, in many

places in Klehini and Jarvis valleys where observations on the structure

of the slates were made the strike is northeast. The apparent ; differences in the structure of the slates and limestones suggests that the limestones may be younger and overlie the slates unconformably. j This interpretation gains added weight from the fact that the slates '; have a structure indicating strong compression, whereas the lime- ; stones are massive and unsheared.

The general age of the bedded rocks is indicated by fossils found ; in the limestones on Porcupine Creek.

A small collection made by Wright 1 in 1903 was doubtfully iden- ".. tified as Lower Carboniferous by G. H. Girty, an identification which , was corrected the following year, when larger collections were made at Pybus and Herring Bays.2 The first collection, which was obtained on Porcupine Creek, contains the following specimens, with revised identifications:

Productus aff. P. gruenewaldti.

Spirifer aff. S. marconi and S. musakheylensis. [ Camarophoria aff. C. margaritovi.

The same fauna is more completely shown in collections from Saginaw Bay, Kuiu Island, and the facies appears to be that of the j Spinfer arcticus zone, which, it is believed, may be correlated with the Russian Artinskian. The indications are that the clastic sedimentary rocks are older rather than younger than the limestones. Presumably the bedded rocks of the region all belong to the Paleozoic, and at least part of

them are definitely of Carboniferous age. ] MINERALIZATION. , The very general mineralized condition of the sedimentary rocks of the region is well described by Wright,3 who says:

The sedimentary rocks have all been more or less mineralized by stringers and veins

of quartz and calcite, but an especially noteworthy impregnation of iron sulphides forms an interrupted zone of mineralization in the southern portion of the sedimentary

1 Wright, C. W,, op. cit., p. 16. 2 Idem, A reconnaissance of Admiralty Island: U. S. Geological Survey Bull. 278, p. 143,1906. 8 Idem, The Porcupine placer district, Alaska: U. S. Geol. Survey, Bull. 236, pp. 17-18.1904.

GOLD PLACER MINING IN PORCUPINE DISTRICT. series. The sulphides in the slates occur as films or frequently as lenticular masses a few inches in width, parallel with the bedding. Two samples of the mineralized slates, one an average across several feet and the other from a rich seam, gave, respectively, $0.41 and $2.48 per ton in gold. Samples from near the mouth of the Porcupine, where the slates are apparently unmineralized, taken by Mr. Brooks during his short visit to this region in 1899, gave traces of both gold and silver. The quartz veins are not very abundant and as a rule are short and small, often merely stringers parallel with the structure of the slates. A few which cut directly across the formation carry galena and sphalerite, with a small amount of chalcopyrite, and though quite harrow, often persist for considerable distances. Calcite veins, which are more numerous than those of quartz, are usually a foot or more in width, and are often weathered to a light-brown color on the surface, while of a bluish color and fine granular structure when freshly broken. They often carry cubes of pyrite, which occasionally measure an inch across. From veins of this nature up McKinley Creek some native gold has been reported. Besides the small veins a quartz ledge 100 feet wide outcrops at an elevation of 2,000 feet on the ridge south of Porcupine. Although apparently quite barren, a small sample from this gave an assay value of $5.28 in gold. A similar ledge occurs across the Klehini at 1,500 feet elevation, on the ridge west of Boulder Creek. About 2 miles below Porcupine is a third mineralized deposit rich in sulphides, with calcite as gangue mineral, but a sample taken here gave an assay value of only 41 cents. The general zone of mineralization from which the placers of Klehini and Salmon River basins have been derived appears to be elongated in a northwesterly direction, extending from a locality south of Salmon River across the basins of Porcupine, Glacier, and Jarvis creeks and into the mountain mass north of Jarvis Glacier. The richness of mineralization varies from place to place, and there are large areas of lean or barren rock in this zone. But there are also remarkably large areas in which sulphide minerals are generally abundant and samples from which are reported to show a substantial gold content on assay. A band of this sort that cuts across Cahoon Creek near its mouth in a slate formation shows abundant quartz veining and sulphides for a width of nearly 1,200 feet. Random samples taken across this belt are reported to assay as much as several dollars a ton, and a large number of assays ranged between $1 and $2 a ton. The northwesternmost point along the general zone of mineralization at which gold has been found is in the mountains north of the lower end of Jarvis Glacier. Here, at an elevation of about 4,500 feet, are several gold quartz ledges in a granitic country rock some 300 feet above its contact with limestone. The lower and apparently the most valuable of the ledges is traceable for over 2,000 feet along the strike. It ranges from 1 foot to 4 feet in width. Assays of numerous samples are reported to give from a few dollars to $70 a ton, the higher tenor generally occurring where the vein is relatively narrow. A silver content of a few ounces a ton is indicated in most samples. Picked specimens give much higher assay returns. Southeast of the main placer area on the slope north of Salmon River are a number of narrow silver-lead veins that show still an-

MINERAL RESOURCES OF ALASKA, 1916. other type of mineralization in the district. So far as known the largest are less than a foot in width. The maximum gold tenor of samples from these veins is said to be about $3 a ton, silver 60 ounces a ton, and lead about 35 per cent. One sample shows a copper content of nearly 3 per cent. The mineralization that has furnished the placer gold of Bear Creek has not been studied geologically. Prospectors report that a broad zone along the ridge west of Bear Creek is heavily pyritized and that it contains, locally at least, commercial grades of copper ore. Specimens from this locality show iron, copper, and zinc sulphides in vein form. HISTORY OF DEVELOPMENT. Gold was first discovered in the Porcupine district in 1898. The next year mining operations were begun on Porcupine Creek, and the great number of prospectors who assembled staked claims on several other creeks of the district. Gold-bearing gravels were found on Bear Creek, on several tributaries of Salmon River, and on the head of Takhin River, but up to the present time productive operations have been almost entirely limited to Porcupine Creek and its tributaries. A little mining was done on Nugget Creek from 1902 to 1911. The ground was then abandoned and no further work has been done. It is estimated by local operators that about $6,000 worth of gold was produced. The gold production of Porcupine Creek and its tributaries from 1898 to 1903 is given by Wright 1 as follows: Gold production of the Porcupine region, 1898-190S. 1902 $140,000 1903 150,000 1898 $1,000 1899 9, 000 1900 50,000 1901 '. 110,000 460,000 The production from these creeks is said to have continued at the rate of $150,000 a year until 1906, when the principal works were destroyed by an unusual flood. From 1907 to 1909 large operations were discontinued, and the only production was made by a few laymen who worked small lots of ground by hand. Production on a large scale was resumed in 1910, and it is reported that an average yearly output of $50,000 was maintained until 1915, when another disastrous flood occurred. The total output of the district from 1898 to 1916, inclusive, estimated on the basis of these very incomplete data, is about $1,200,000. In 1908 the Porcupine Mining Co. was organized to exploit the placers of the main Porcupine Creek on a large scale. It was financed in the Eastern States, and in view of the equipment installed in the next few years it must have had a large investment fund. The first move of the new company was to construct a flume a mile long, 24 to i Wright, C. W., op. cit., p. 13.

30 feet wide, and 6 feet deep, supported on piles, to carry the waters of Porcupine Creek past the placer ground to be worked. This piece of construction, which required nearly a million feet of lumber and several thousand piles, was completed late in the summer of 1909, and mining was begun at the lower end of the canyon. This company operated until August, 1915, when the lower part of the flume was demolished and the pits were filled in by a flood. In the last few years operations were conducted under receivership but with the same local management. After the disastrous flood of 1915 the property and holdings of the company were taken over by the Alaska Corporation. This concern in 1916 repaired the upper section of the old flume, constructed a new high-line flume to deliver water to the giants, and began the reexcavation of the buried workings. Little mining was done on the tributaries of Porcupine Creek before 1908, when the Cahoon Creek Gold Mining Co. began work on McKinley and Cahoon creeks. This company has continued to operate to the present time, working out the placers on Cahoon Creek near its mouth and for about 2,000 feet down McKinley Creek below Cahoon. The plan followed in the operations on McKinley Creek was essentially similar to that employed on Porcupine Creek. The stream was diverted into a wooden flume, making the stream bed available for hydraulic mining. Below the workings on McKinley Creek the stream runs through a narrow box canyon. The difficulty of diverting the stream in this reach has thus far prevented the exploitation of the gravels of its bed. In 1916 the company was engaged in working the placers of a high, glacially filled channel on the right side of McKinley Creek, opposite the reach of the modern channel that has been worked out. A little mining was done on the head of Cahoon Creek in the early days of the camp, but these operations are said to have met with slight success, and the hope of working this ground on any large scale has long been abandoned. However, a little prospecting and "sniping" have been done from time to time by laymen. The most notable developments in the district in the last few years have been the investigation of the Glacier Creek placers by drilling and the installation of a large hydraulic plant to work this ground. The Glacier Creek placers were staked in the early days of the district, but repeated attempts to prospect and mine the ground by ordinary methods failed owing to the depth of the gravels and the abundance of ground water. In 1911 the claims, which had been abandoned by the previous holders, were restaked, and systematic drilling was begun. Drill sections across the valley bottom were made at short intervals for over a mile upstream from the margin of the Klehini Valley. On the basis of the results of this investigation

MINERAL RESOURCES OP ALASKA, 1916. extensive preparations were made to work a lower section of the valley 4,200 feet long by hydraulic methods. The installation of a very complete plant, including dams, flumes, pipe lines, giants, and hydraulic elevator, was finished in midsummer, 1915, but operation was prevented for the rest of the season by unusual floods. In 1916 work was started early in spring, but owing to damage done to the workings by a flood the later part of June the season netted but little productive operation. SUMMARY OF MINING IN 1916. Mining in the Porcupine district in 1916 was confined to Porcupine Creek, its main east tributary, McKinley Creek, and Glacier Creek. A single hydraulic plant worked on each stream throughout the summer. The principal, work done on Porcupine and Glacier creeks consisted of the installation of hydraulic equipment and the repairing of damage done to workings and equipment by floods, so that little productive mining was accomplished. Two small plants were worked by hand on the lower Porcupine part of the summer. The plant on McKinley Creek opened a new pit in an old elevated channel and worked out a considerable area, although the operations were hampered somewhat by the presence of an overburden of glacial till 60 feet thick in which there are numerous large boulders. About 50 men at an average were employed during the summer in the whole district, being divided about equally among the three active creeks. Although the production for 1916 was small, it is reported that the plants have all been put in good repair and that conditions indicate that a very considerable production may be made in 1917.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA.1 By GEORGE H. CANFIELD. INTRODUCTION. The streams of Alaska have been important factors in its industrial growth. The success of placer mining in northern and central Alaska has depended primarily on the water available for hydraulicking and dredging, and in southeastern Alaska water power has long been used by mines, canneries, sawmills, and other industries, although until recently most of the plants have been small. Since 1906 the United States Geological Survey has made systematic studies of the water resources of Alaska. Investigations with special reference to placer mining have been made in Seward Peninsula 2 and the Yukon-Tanana region,3 and reconnaissance surveys for water power have been made about Prince William Sound, Copper River, Kenai Peninsula, and in other parts of southeastern Alaska. In the summer of 1914 Leonard Lundgren, district engineer of the Forest Service, made a reconnaissance of water-power sites to determine the possibility of establishing the pulp industry in the Tongass National Forest, which covers a large part of southeastern Alaska. In connection with this reconnaissance a census of water powers was taken (see following table), which has been revised by Mr. Lundgren to January 1, 1917, and is here published by courtesy of the Forester. Developed water powers in southeastern Alaska Jan. 1, 1917, in horsepower. [Prepared by Leonard Lundgren,district engineer,U. S. Forest Service.] Ketchikan region: Citizens Light, Power & Water Co 2,000 New England Fish Co 2,200 Miscellaneous plants 1,000 5,200 Wrangell region 1 In cooperation with the United States Forest Service. 8 Henshaw, F. F., and Parker, G. L., Surface water supply of Seward Peninsula, with a sketch of the geography and geology by P. S. Smith, and a description of methods of placer mining by A. H. Brooks: U. S. Geol. Survey Water-Supply Paper 314, 1913. s Ellsworth, C. E., and Davenport, R. W., Surface water supply of the Yukon-Tanana region, Alaska: U. S. Geol. Survey Water-Supply Paper 342,1915; A water-power reconnaissance in south-central Alaska, with a section on southeastern Alaska by J. C. Hoyt: U. S. Geol. Survey Water-Supply Paper 372, 1915.

MINERAL RESOURCES OF ALASKA, 1916. Sitka region: SitkaWharf& Power Co Chichagoff Mining Co Miscellaneous plants. 1,250 Juneau region: Alaska-Tread well Mining Co.: Douglas Island plant 4,000 Sheep Creek plant 4,100 Nugget Creek plant 5, 700 13,800 Alaska-Gastineau Mining Co.: Salmon Creek plant, No. 1 5,000 Salmon Creek plan No. 2 5,000 Annex Creek plant 5,000 15,000 Alaska Electric Light & Power Co 1,000 Miscellaneous plants 1,000 30,800 Skagway region 37,350 During the last few years some large water-power plants have been installed near Juneau to supply power for mining, and attention has been called to the feasibility of improving other power sites in that region and elsewhere in southeastern Alaska, to meet the increasing demand for power to be used in mining, lumbering, and fisheries, and the possible future demand for its use in the manufacture of wood pulp and electrochemical products. The streams on which it is possible to develop power and the bays or other water bodies into which these streams discharge are listed in the following table and shown on the map (PL IX): Streams affording power sites in southeastern Alaska, with position or water 'bodies into which theyfloiv. Mainland. Porcupine Pviver, near Porcupine. 1 Endicott River, west coast of Lynn Canal. Sherman Creek. Cowie and Da vies creeks, Berners Bay. Lemon Creek, near Juneau.2 Gold Creek, at Juneau. Sheep Creek, near Juneau. Carlson Creek, Taku Inlet.3 Turner Lake outlet, Taku Inlet.4 Speel River, Speel River project, Port Snettisham.5 Grindstone Creek, north shore of Stephens Passage. 5 Rhine Creek, north shore of Stephens Passage. 5 1 Gaging station maintained in 1909 by Porcupine Gold Mining Co. 8 Gaging station maintained for short period by mining company of Juneau. a Gaging station being maintained by Alaska-Gastineau Mining Co. of Juneau. Gaging station maintained in 1908 and 1909 by Alaska-Treadwell Gold Mining Co. 6 See list of miscellaneous measurements at end of report.

U. S. GEOLOGICAL SURVEY BULLETIN 662 PLATE IX SCALE ON .56TH PARALLEL 10 0 10 4O SO 70 MILES

Stream-gaging station Precipitation station MAP OF SOUTHEASTERN ALASKA, SHOWING LOCATION OF GAGING STATIONS.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 103 Long Lake outlet, Speel River project, Port Snettisham. 1 Crater Lake outlet, Speel River project, Port Snettisham. 12 Tease Lake outlet, Speel River project, Port Snettisham. Sweetheart Falls Creek, south arm of Port Snettisham.3 Port Houghton, Stephets Passage. Farragut Bay, Frederick Sound. Mill Creek, near Wrangell.3 Bradfield Canal, upper end of Cleveland Peninsula. Smugglers Cove, southeast shore of Cleveland Peninsula. Helm Bay, southeast shore of Cleveland Peninsula. Shelockum Lake outlet, Bailey Bay.3 Chickamin River, east shore of Behm Canal. Rudyerd Bay, east shore of Behm Canal. Baranof Island. Port Conclusion, southeast coast. Patterson Bay, east coast. Red Bluff Bay, east coast. Cascade Bay, east coast. Baranof Lake outlet, Warm Spring Bay, east coast.3 Kasnyku Bay, east coast. Green Lake outlet, Silver Bay, west coast.3 Necker Bay, west coast. Deep or Redoubt Lake, west coast. Chichagof Island. Slocum Arm, west coast. Suloia Bay, Peril Strait. Khaz Bay, west coast. Freshwater Bay, east coast. Sitkoh Bay, southeast coast. Basket Bay, southeast coast. Pinta Bay, west coast. Admiralty Island. Kootznahoo Inlet, west coast. Hood Bay, west coast. Eosciusko Island. Davidson Inlet. Prince of Wales Island. Karta River, Karta Bay.3 Whale Passage, behind Thorne Island, northeast coast. Myrtle Lake outlet, near Niblack post office. Reynolds Creek, near Coppermount.2 Revillagigedo Island. Orchard Lake outlet, at Shrimp Bay.3 Beaver Falls, George Inlet. White River, George Inlet. Swan Lake outlet, east shore near head of Carroll Inlet. Fish Creek, Thorne Arm.3 Gokatchin Creek, Thorne Arm.2 Ketchikan Creek, at Ketchikan.3 Annette Island. Tamgas Harbor. i Gaging station maintained since January, 1913, by the Speel River project of Juneau. 8 See list of miscellaneous measurements at end of report. 8 Gaging station maintained by Geological Survey.

MINERAL RESOURCES OP ALASKA, 1916. Lack of definite information in regard to the quantity of water available and other physical factors that determine the feasibility of a power site has been one of the principal impediments to development. For this reason a systematic investigation, designed to determine the location and the feasibility of water-power sites in southeastern Alaska, was begun by the Geological Survey, in cooperation with the Forest Service, in the spring of 1915. The practicability of a water-power site depends on the quantity of water available, the fall, and the possibility of storing water. Information in regard to fall and storage can be obtained by surveys at any time, but the volume and distribution of flow can be determined only by observations extending over several years, as future flow must be predicted from that of the past. In beginning the investigations, therefore, the collection of stream-flow data was given precedence and constituted the principal work. Some general information, however, has been obtained, and in the fall of 1915 a few rainfall stations were established at higher elevations to supplement observations at mean sea level by the United States Weather Bure'au. As a result of the investigations records of flow are now available for 19 gaging stations, as shown by the following list, and indicated by corresponding numbers on Plate IX. The date of establishment is indicated in parentheses. 1. Fish Creek near Sea Level, Revillagigedo Island (May 19, 1915). 2. Ketchikan Creek at Ketchikan (established Nov. 1,1909; discontinued June 30, 1912; reestablished July 1, 1915). 3. Swan Lake outlet at Carroll Inlet, Revillagigedo Island (Aug. 24, 1916). 4. Orchard Lake outlet at Shrimp Bay, Revillagigedo Island (May 28, 1915). 5. Shelockum Lake outlet at Bailey Bay (June 4, 1915). 6. Karta River at Karta Bay, Prince of Wales Island (July 16, 1915). 7. Mill Creek .on mainland near Wrangell (June 17, 1915). 8. Green Lake outlet at Silver Bay, near Sitka (Aug. 22, 1915). 9. Baranof Lake outlet at Baranof, Baranof Island (June 28, 1915). 10. Sweetheart Falls Creek near Snettisham (July 31, 1915). 11. Crater Lake outlet at Speel River, Port Snettisham (Jan. 23, 1913). 12. Long Lake outlet at Port Snettisham (Jan. 23, 1913). 13. Long River below Second Lake at Port Snettisham (Nov. 11, 1915). 14. Speel River at Port Snettisham (July 15, 1916). 15. Grindstone Creek at Stephens Passage (May 6, 1916). 16. Carlson Creek at Sunny Cove, Taku Inlet (July 18, 1916). 17. Sheep Creek near Thane (July 26, 1916). 18. Gold Creek at Juneau (July 20, 1916). 19. Sherman Creek at Kensington mine, Lynn Canal (Aug. 17, 1914). The available power sites in each area were carefully considered, and gaging stations were established at those which apparently afforded the greatest opportunities for development. The records have been collected in accordance with the standard methods used elsewhere in the United States by the Geological Survey. Owing to the inaccessibility of the stations, water-stage recorders were used at ail the stations except that on Ketchikan Creek, and cables

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 105 have been installed from which discharge measurements are made. Special arrangements were made for observations through the winter to obtain a record of the low-water flow which occurs at that season. The data collected at the gaging stations are presented in the following pages and include a general description of each station and tables showing the results of discharge measurements and the computed daily discharge. Much of the work has been made possible by the use of the Forest Service launches, on which transportation has been furnished to the engineers and others engaged in installing and maintaining the stations. The local knowledge of the Forest Service employees has also been of great assistance in carrying on the work, and special acknowledgment is due to W. G. Weigle, forest supervisor at Ketchikan, who has represented the Forest Service in the cooperation; to Leonard Lundgren, district engineer; and to George L. Drake, J. W. Wyckoff, C. T. Gardner, George H. Peterson, James Alien, W. H. Babbitt, Lyle Blodgett, and Milo Caughrean, who have assisted in various ways. During the winter of 1916-17 the field work was carried on by C. 0. Brown, assistant engineer, United States Geological Survey. The following individuals and organizations assisted in maintaining gaging stations as indicated: T. J. Jones, Seattle, Wash., furnished a Stevens water-stage recorder, materials, and labor for installing a gage on Swan Lake outlet. The Alaska Gastineau Mining Co. installed gages and furnished gage-height records for Gold Creek near Juneau, Sheep Creek near Thane, and Carlson Creek at Sunny Cove. The Alaska Taku Mining Co. furnished a Lietz gage, labor, material, and transportation for the installation of a gage on Grindstone Creek at Stephens Passage. The Speel River Project (Inc.), of Juneau, installed and maintained gages and furnished gage readings and discharge measurements for Crater Lake outlet at Speel River, Long Lake outlet at Port Snettisham, Long River below Second Lake, and Speel River at Port Snettisham. The Kensington Mining Co., of Comet, furnished gage readings for Sherman Creek at Kensington mine. The Citizens Light, Power & Water Co., of Ketchikan, furnished gage readings for Ketchikan Creek at Ketchikan. STATION RECORDS. FISH CREEK NEAR SEA LEVEL, REVILLAGIGEDO ISLAND. LOCATION. In latitude 55° 24' N., longitude 131° 12' W., near outlet of Lower Lake on Fish Creek, 600 feet from tidewater at head of Thorne Arm, 2 miles northwest of mine at Sea Level, and 25 miles by water from Ketchikan.

MINERAL RESOURCES OP ALASKA, 1916. DRAINAGE AEEA. Not measured. RECORDS AVAILABLE. May 19, 1915, to December 31, 1916! GAGE. Stevens water-stage recorder on right shore of Lower Lake, 200 feet above outlet. DISCHARGE MEASUREMENTS. At medium and high stages made from cable across creek, 1 mile upstream from gage and 500 feet above head of Lower Lake; at low stages made by wading at cable. Only one small creek enters Lower Lake, at point opposite gage, between the cable site and control section. CHANNEL AND CONTROL. The lake is about 500 feet wide opposite the gage. Outlet consists of two channels, each about 60 feet wide, separated by an island 40 feet wide. From the lake to tidewater, 200 feet, the creek falls 20 feet. Bedrock exposed at the outlet of the lake forms a well-defined and permanent control. EXTREMES OF DISCHARGE. Maximum stage recorded during period, 4.94 feet at 3 a. m. October 15, 1915 (discharge, computed from an extension of the rating curve, 4,020 second-feet; revised since published in Bulletin 642); minimum stage recorded, 0.50 foot February 11, 1916 (discharge, 22 second-feet). ICE. Lower Lake freezes over, but as gage is set back in the bank ice does not form in well, and the relatively warm water from the lake and the swift current keep the control open. ACCURACY. Stage-discharge relation practically permanent; affected by brush lodged at control August 23 to December 31. Rating curve used May 19, 1915, to August 23,1916, well denned below and fairly well defined above 1,500 secondfeet. Rating curve used after August 23, 1916, when control was obstructed by brush, defined below 1.5 feet (discharge, 253 second-feet) by discharge measurements made January 25,1917, at gage height 1.48 feet (discharge, 243 second-feet) and March 2, 1917, at gage height 0.86 foot (discharge, 65 second-feet). Above a stage of 1.50 feet the curve was drawn 0.16 foot above curve applicable when control was not obstructed. Operation of water-stage recorder satisfactory except for periods indicated by breaks in record shown in the footnote to dailydischarge table. Daily discharge ascertained by applying to rating table mean daily gage heights determined by inspecting gage-height graph, or, for days of considerable fluctuation, by averaging results obtained by applying to rating table mean daily gage heights for regular intervals of day. Results excellent, except for short periods of break in record and for period when control was obstructed by brush, for which they are fair. There are three large lakes in the upper drainage basin: Big Lake, 2 miles from beach at elevation 275 feet, covers 1,700 acres; Third Lake, 250 acres; and Mirror Lake, at elevation 1,000 feet, 800 acres. Two-thirds of the drainage basin is covered with a thick growth of timber and brush interspersed with occasional patches of beaver swamp and muskeg. Only the tops of the highest mountains are bare. This large area of lake surface and vegetation, notwithstanding the steep slopes and shallow soil, affords a little ground storage and after a heavy precipitation maintains a good run-off. During a dry, hot period in summer, however, after the snow has melted, the flow becomes very low because of lack of ice or glaciers in the drainage basin. Discharge measurements of Fish Creel: near Sea Level during the period May 19,1915, to Dec. 31, 1916. Date. May 20 July 10 Sept. 13 Oct. 13 Made by G. H. Canfleld do G.H. Canfleld. Gage height. Feet. Discharge. Sec.-ft. 1,120 Date. Jan. 26 July 30 Aug. Made by G. H. Canfield do do do Canfleld and Brooks... . Gage heignt. Feet. Discharge. Sec.-ft. 1,360

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 107 Daily discharge, in second-feet, of Fish Creek near Sea Level for the period May 19, 1915, to Dec. 31, 1916. 1. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Day. 1. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Day. Jan. Feb. 1,110 1,170 9fi4 Mar. 99fl I'M 9nfi May. Apr. dQO June 24, 17! 15J May. 9fiQ fi9S f, f

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?5 )6 i? '0 tt. ? Dct. ,030 ,120 2,510 ,160 ,950 ,230 ,320 ,520 ,220 ,120 ,170 Oct. 1,550 1,190 Nov. 1,010 1,070 Nov. Dec. Dec. NOTE. Discharge Sept. 6-12, Nov. 23 to Dec. 1, 1915, Jan. £-5, Feb. 7-11,1829, Oct. 16-30,1916, estimated, because of gage clock stopping, from maximum and minimum stages indicated by recording pencil, from climajip records, and from comparison of the hydrograph for this station with that for Karta River.

MINERAL RESOURCES OF ALASKA, 1916. Monthly discharge of Fish Creek near Sea Level for the period May 19, 1915, to Dec. SI, Month. Mayl9-31 July September The period January.. Mby July Discharge in second-feet. Maximum. 1,720 3,160 1,070 1,170 1,300 3,160 1,550 Minimum. Mean. Run off (tota in acre-feet). 8,460 20,900 7,500 26,600 16,300 79,800 60,800 27,100 24,200 4,520 17,000 11,700 24,500 28,000 34,800 28,700 20,700 22,200 304,000 31,000 22,200 11,900 65,100 KETCHIKAN CREEK AT KETGHTKAN. LOCATION. One-fourth mile below power house of Citizens Light, Power & Water Co., one-third mile northeast of Ketchikan post office, downstream 200 feet from mouth of Schoenbar Creek (entering from right), 1£ miles from mouth of Granite Basin Creek (entering from left), and 1$ miles from outlet of Ketchikan Lake. DRAINAGE AREA. Not measured. RECORDS AVAILABLE. November 1,1909, to June 30,1912; June 9,1915, to December 31, 1916. GAGE. Vertical staff fastened to a telephone pole near board walk on left bank at bend of creek 200 feet downstream from mouth of Schoenbar Creek; read by employee of the Citizens Light, Power & Water Co. The gage used since June 9, 1915, consists of the standard United States Geological Survey enameled gage section graduated in hundredths, half-tenths, and tenths from zero to 10 feet The original gage established November, 1909, and read until June 30, 1912, is at same location and same datum. It is a staff with graduations painted every tenth. DISCHARGE MEASUREMENTS. At medium and high stages from footbridge about 500 feet upstream from gage; measuring section poor, as the bridge makes an angle of 20° with the current, and at high stages the flow is broken by large stumps near left bank and at middle of bridge; at low stages, by wading 50 feet below bridge or at another section 100 feet above gage. The flow of Schoenbar Creek has been added to obtain total flow past gage. CHANNEL AND CONTROL. Gage is located in a large deep pool of still water at a bend in creek. The bed of the stream at the outlet of this pool is a solid rock ledge, which forms an excellent permanent control at the gage.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 109 EXTREMES OF DISCHARGE. Maximum stage recorded during 1916, 5 feet July 29 (discharge, 1,490 second-feet); minimum stage recorded, 0.35 foot in January and February (discharge, 40 second-feet). 1909-1912 and 1915-16: Maximum stage recorded, 8.2 feet December 2, 1911 (discharge, 3,400 second-feet); minimum stage recorded, 0.28 foot September 24, 1915 (discharge, 34 second-feet). ICE. Ice forms along banks but control remains open. DIVERSIONS. A small quantity of water is diverted above the station for the use of the town of Ketchikan, the New England Fish Co., and the Standard Oil Co. REGULATION. Small timber dam and headgates are located at outlet of Ketchikan Lake. Water diverted through power house is returned to creek a' ove gage but causes very little diurnal fluctuation. During low water the flow is increased by water from the reservoir. ACCURACY. Stage-discharge relation permanent. Rating curve well defined below and poorly defined above 2,000 second-feet. Gage read-once daily. Daily discharge ascertained by applying daily gage heights to rating table. Results fair. Discharge measurements of Ketchikan Creek at Ketchikan during the period June 9, 1915, to Dec. 31, 1916. Date. July 17 Sept. 12 Oct. 27 Made by Hoyt and Canfield Carifteld and Wycofl . . . do Gage height. Feet.. Discharge. Scc.-fl. Date. Apr. 13 July 29 Dec. Made by G.H. Canfleld. do do do C. O. Brown Gage height. Feet. n 7"; Discharge. Sec.-ft. Wl 1,470 NOTE. Discharge of all measurements includes measured or estimated flow of Schoenbar Creek. Daily discharge, in second-feet, of Ketchikan Creek at Ketchikan for the years ending Sept. SO, 1910-1912 and 1915-16. Day. 1 2 3 4 5 0.. 7 8 9 10 11 12 13 15 1C, 17 IS 19 20 21 22 23 24 25 20 27 28 29 Oft 31 Oct.

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Apr. GO 70 May. 43o June. July. 2,040 Aug. 1,540 9fi9 S3 Sept. 103210° IS Bull. 662-

MINERAL RESOUECES OF ALASKA, 1916. Daily discharge, in second-feet, of Ketchikan Creek at Ketchikan for the years ending Sept. 80, 1910-1912 and 1915-16 Continued. Day. 1. 5 6 7 10 11 TO 14 15 16 17 18 19 20 21 22 25 26 27 28 9Q 31 O 3 4 5 6 7 8 9 10 11 12 14 15 16 17 18 19 :.. 20 22. 24 26 27. 28 9Q 31 Oct. A QO 43R 1,700 1,290 2,220 1OC 191; 19 Q3 Nov. ins 9fi9 ifin Dec. 4fi4 1,010 1,440 3,400 1,760 Jan. Q3 Q3 43fi 43R Feb. Mar. '44 Apr. 7Q May. '296 June. 1,190 1,010 '86 July. 1,290 Aug. Sept. 1QO

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. HI Daily discharge, in second-feet, ofKetchikan Creek at Ketchikan for the years ending Sept. SO, 1910-1912 and 1915-16 Continued. Day. 1 2." 3 4 5 6 7. 8. 9 10 Day. 1915-lf 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 ... 27 28 29 30 31 Day. 1 2 3 4 5 6 7 8. 9. 10 Jul f f If ?f 1r Oct 7f 6f fif 6f 7W

W row

Au t 2,64 Oct. S40 ,540 5?3 Nov 2&. 29(

26' 22f 91f 17f 14'

iO

ifi !9 n

) Sei f Vov. 2?,o ?,85 ?,oo IfiO ins 80S 80S ISO ISO Dec rui? >t. KW D f f sO )3 o 1? ec. W WO WO ?00 !00

Day. Jan. Day. July. Feb. Oct. Aug. 1,920 Mar. Nov. Sept. Apr. Dec. ] ?,5 May. D 1£ Day. June. ay. July. July. 200' 1,060 1,010 1,010 Oct. Aug. Aug. Nov. Sept.

SB Sept. Dec. fi4 NOTE. No gage readings Nov. 3-5, 8, 13-15, 17, 20, 21, 23-26, 28, 29, Doc. 3, 4, 6, 7, 9, 21, 25, 26, and 28, 1909; Jan. 2,10,14, 15, 19 20, 22, 24, Feb. 9, 11, 13, 15, 19, 26-28, Mar. 1, 3-8, 10, 15,18, 24, Apr. 3, 4, 6, 8, 16, 21, and May 6,1910; discharge estimated. Discharge estimated from climatic records as follows: Jan. 14 to Mar. 17,1911; Jan. 2-14,16-26, Jan. 28 to Feb. 13, and Feb. 17-29,1916. Estimates of discharge Nov. 1,1909, to June 30.1912, and June 9, 1915, to Feb. 29, 1916, differ from that published in Bulletin 642 because of a revision of rating curve, based upon discharge measurements made in 1916.

MINERAL RESOURCES OP ALASKA, 1916. Monthly discharge ofKetchikan Creek at Ketchikanfor the years ending Sept. 30,1910-1912 and 1915-16. Month. November. January. . . February. March. April. May June July August . September. . The period October ... November. December . . . January. February March April June. . . July September . The year. October. November. December. February. April. July August. September. The period. . July August. The year Discharge in second-feet. Maximum. 2,040 1,540 2,220 1,440 1,190 1,290 2,220 3,400 2,640 1,060 1,540 Minimum. Mean. ' 190 Run-off (total in acre-feet). 7,740 4,700 4,690 4,550 14,600 8,030 17,900 19, 600 23,000 15,700 10,900 131,000 33, 800 12,600 20,800 7,690 3,890 6,150 9,640 . 15,300 19,900 18,300 7,870 11,200 167,000 10,600 10, 100 25,300 9,280 12,300 3,820 6,660 95,200 5,320 18, 600 6,310 30, 200 22,800 14, 200 11,700 2,940 6,270 6,760 9,220 12,200 14,300 17,300 10, 100 13,600 141,000 14,300 12,000 6,760 33, 100 NOTE. See footnote to daily-discharge table.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 113 SWAN LAKE OUTLET AT CARROLL INLET, REVILLAGIGEDO ISLAND. LOCATION. Halfway between Swan Lake and tidewater; on east shore of Carroil Inlet, 1 mile from its head; 30 miles by water from Ketchikan. DRAINAGE AREA. Not measured. RECORDS AVAILABLE. August 24 to December 31, 1916. GAGE. Stevens water-stage recorder on left bank, half a mile from tidewater; reached by a trail which leaves beach back of old cabin one-fourth mile south of mouth of creek. DISCHARGE MEASUREMENTS. At medium and high stages, made from a cable across stream 100 feet downstream from gage; at low stages made by wading. CHANNEL AND CONTROL. The gage well is in a deep pool 25 feet upstream from a contracted portion of channel, where a fall of a foot over bed rock forms a permanent control. The effect of .the violent fluctuation of the water surface outside of gage well is decreased in the inner float well because the intake holes at the bottom are very small. At the cable section the bed is rough, the water shallow, and the current very swift. Point of zero flow is at gage height 0.0±0.2 foot. EXTREMES or DISCHARGE. Maximum stage recorded during period, 4.74 feet at 7 p. m. October 28 (discharge, 1,210 second-feet); minimum stage recorded, 1.23 feet December 28 (discharge, 73 second-feet). ICE. Stage-discharge relation not affected by ice. ACCURACY. Stage-discharge relation permanent. Rating curve fairly well defined between 50 and 900 second-feet. Operation of water-stage recorder satisfactory except December 8-31. Daily discharge ascertained by applying to rating table mean daily gage heights determined by inspecting gage-height graph. Results fair. Swan Lake, whose area is about 350 acres, is 1$ miles from tidewater, at an elevation of 225 feet above sea level. Discharge measurements of Swan Lake outlet at Carroll Inlet during period Aug. 24 to Dec. 31, 1916. .Date. Nov. 1 Made byGage heigTit. Feet,. Discharge. Sec.-ft. Date. Made byGage height. Feet. Discharge. Sec.-//.. Daily discharge, in second-feet, of Swan Lake outlet at Carroll Inlet for the period Aug. 24 to Dec. 31, 1916. Day. 10 11 12 13 14 15 Aug. Sept. ' 168 Oct. Nov. Dec. Day. 16 17 18 1920 :.. 21 22 23 24 25 26 27 28 29. Oft

Aug. Sept. Oct. 1,090 1,020 Nov. 44Q Dec. NOTE. Discharge Dec. 8-31 estimated from maximum and minimum stages indicated by recording pencil and comparison with gage-height graph for Irish Creek near Sea Level.

MINERAL RESOURCES OF ALASKA, 1916. Monthly discharge of Swan Lake outlet at Carroll Inlet for the period Aug. 24 to Dec. 31, Month. August 24-31 : :.. September November The period. . Discharge in second-feet. Maximum. 7G6 1,090 Minimum. Mean. Run-off (total in acre-feet). 6,650 26,000 30,500 21,000 10, 600 94,800 ORCHARD LAKE OUTLET AT SHRIMP BAY, REVILLAGIGEDO ISLAND. LOCATION In latitude 55° N., longitude 131° 27' W., at outlet of Orchard Lake, one-third mile from tidewater at head of Shrimp Bay, an arm of Behm Canal, 46 miles by water from Ketchikan. DRAINAGE AREA. Not measured. RECORDS AVAILABLE. May 28, 1915, to December 31, 1916. GAGE. Stevens water-stage recorder on right bank 300 feet below Orchard Lake and 100 feet above site of timber-crib dam, which was built in 1914 for proposed pulp mill and washed out by high water August 10, 1915. Datum of gage lowered 2 feet September 15, 1915. Gage heights May 29 to August 10 referred to first datum; August 11, 1915, to August 17, 1916, to second datum. Datum of gage lowered 1 foot August 17, 1916. Gage heights August 18 to December 31, 1916, referred to this datum. DISCHARGE MEASUREMENTS. At medium and high stages made from cable 50 feet downstream from gage; at low stages by wading near cable. CHANNEL AND CONTROL. From Orchard Lake, at elevation 134 feet above high tide, the stream descends in a series of rapids for 1,000 feet through a narrow gorge, then divides into two channels and enters the bay in two cascades of 100-foot vertical fall. Opposite the gage the water is deep and the current sluggish. At the site of the old dam bedrock is exposed, but for 30 feet upstream the channel is filled in with loose rock and brush placed during coLstruction of dam. This material forms a riffle which acts as a control for water surface at gage at low and medium stages and is scoured down when ice goes out of lake; the rock outcrop at site of old dam acts as a control at high stages and is permanent. EXTREMES OF DISCHARGE. Maximum stage recorded during period, 8.4 feet at 2 a. m. October 16, 1915 (discharge, 6,230 second-feet); minimum, estimated, 20 second-feet February 11, 1916. ICE. Ice forms on Orchard Lake, but because of swift current and relatively warm water from lake the outlet and control remain open. ACCURACY. Stage-discharge relation changed August 10, 1915, when timber dam below gage was washed out, and changed for low stages February 15 and April 13, when the old gravel cofferdam under cable was scoured down by ice passing out of lake. Fifteen discharge measurements were made during period, by means of which rating curves have been constructed applicable as follows: May 28 to August 10 well-defined below and poorly defined above 2,000 second-feet; August 11, 1915, to February 14, 1916, well defined; February 15 to April 12, poorly defined; April 13 to December 31, 1916, fairly well defined. Operation of water-stage recorder satisfactory, except for periods when clock stopped, as shown in footnote to daily-discharge table. Daily discharge ascertained by applying to rating table mean daily gage heights, determined by inspecting

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 115 gage-height graph, or for days of considerable fluctuation by averaging the discharge for equal intervals of the day,_except April 13 to November 2, 1916, for which the daily discharge was ascertained by use of the discharge integrator. Results fair. The highest mountains on this drainage basin are only 3,500 feet above sea level and are covered to an elevation of 2,500 feet by a heavy stand of timber and a thick undergrowth of brush, ferns, alders, and devil's club. The topography is not so rugged as that of the area surrounding Shelockum Lake, and the proportion of vegetation, soil cover, and lake area is greater, so that more water is stored and the flow in the Orchard Lake drainage basin is better sustained. Discharge measurements of Orchard Lake outlet at Shrimp Bay for the period May 28, 1915, to Dec. SI, 1916. Date. May 29 July 8 Sept. 15 Oct. 16 Made by G.H.Canfield. do do G.H.Canfield.. do do Gage height. Feet. Discharge. Sec.-//. 5,280 4,270 2,720 Date. Jan. 20 Mar. 15 Apr. 18 Aug. 18 Nov. 3 Dec. Made by G. H. Canfleld. do do do do C. O. Brown Gage height. Feet. Discharge. Sec.-ft. a Datum of gage lowered 2 feet before making discharge measurement. 6 Datum of gage lowered 1 foot before making discharge measurement. Daily discharge, in second-feet, of Orchard Lake outlet at Shrimp Bay for the period May 28, 1915, to Dec. 31,1916. Day. 1 2 3 4 5 0 7 8 9 10 11 12. : 13 14 15 16 17 18. 19. 20 21 22. ..I 23 24. 25 26 27 28 29 30 31 May.

June. July. Aug. 3,480 4,700 2,550 1,980 1,200 1,250 1,020 Sept. 1,010 1,720 1,090 Oct. 1,280 1,400 1,260 1,520 1,300 4,140 4,990 2,430 1,170 1,260 1,320 1,010 1,570 1,260 1,840 1,480 Nov. 1,260 1,000 Dec. 1,130

MINERAL RESOURCES OP ALASKA, 1916. Daily discharge, in second-feet, of Orchard Lake outlet at Shrimp Bay for the period May 28, 1915, to Dec. 31., 1916 Continued. Day. 1. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 ; 29. 30 31 Jan. Feb. 2"8 1,070 1,150 Mar. Apr. 1,380 1,100 May. 1,020 1,050 1,100 1,020 1,160 1,350 June. 1,430 1,370 1,430 1,080 1,130 1,270 1,520 1,560 1,360 1,240 1,130 1,080 1,160 1,060 S88 July. 1,750 1,900 1,380 1,020 1,730 2,110 1,370 Aug. 1,490 1,030 1,020 Sept. 8-! 5 1,040 1,070 1,200 1,130 Oct. 1,320 '396 1,200 1,010 1,600 1,480 Nov. '195 Dec. 4S8 NOTE. Discharge estimated (no gage record) for following periods: Aug. 22 to Sept. 2, from climatic records and flow before and after the period" Nov. 3-16, 1915, from climatic records and minimum stage indicated by recorder; Jan. 3 to Feb. 13, from climatic records and one current-meter measurement; Mar. 2-8, because water surface was below bottom of well, and July 13-17,19-31, Aug. 1,2,15, and 16,1916, from climatic records and comparison with records of flow for Sheiockum Lake outlet. Monthly discharge of Orchard Lake outlet, at Shrimp Bay for period June 1, 1915, to Dec. 31, 1916. Month. June July August April June. July October. The period. . ° Discharge in second-feet. Maximum. 4,700 1,720 4,990 1,260 1,130 1,150 1,380 1,350 1,560 2,110 1,490 1,200 4,990 1,600 Minimum. Mean. 1,270 1,050 Kim-off (total in acre-feet). 28, 700 14, 700 43,000 23,300 110,000 78, 100 29,500 24,100 3,950 18,300 10, 300 33,800 '48,900 62,500 54,800 30,100 32,900 427,000 38, 600 23,400 11, 100

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 117 SHELOCKUM LAKE OUTLET AT BAILEY BAY. LOCATION. In latitude 56° 00' N., longitude 131° 36' W. on mainland near outlet of Shelockum Lake, three-fourths mile by Forest Service trail from tidewater at north end of Bailey Bay, and 52 miles by water north of Ketchikan. DRAINAGE AREA. 18 square miles (measured on sheets Nos. 5 and 8 of the Alaska Boundary Tribunal, edition of 1895). RECORDS AVAILABLE. June 1, 1915, to December 31, 1916. G'AGE. Stevens water stage recorder on right shore of lake, 250 feet above outlet. DISCHARGE MEASUREMENTS. Made from cable across outlet of lake, 200 feet below gage and 50 feet upstream from crest of falls. CHANNEL AND CONTROL. Opposite the gage the lake is 600 feet wide; at the outlet bedrock is exposed and the water makes a nearly perpendicular fall of 150 feet. This fall forms an excellent and permanent control for the gage. At extremely high stages the lake has another outlet about 200 feet to left of main outlet. Point of zero flow is at gage height 0.6 foot. EXTREMES OF DISCHARGE. Maximum stage recorded during period, 6.5 feet (estimated) October 15,1915 (discharge, 2,440 second-feet); minimum flow, estimated from gage record and climatic data, 9 second-feet February 11, 1916. ICE. Ice forms on Shelockum Lake and at gage, but because of the swift current and relatively warm water from lake, the control remains open and stagedischarge relation is not affected by ice. ACCURACY. Stage-discharge relation permanent. Rating curve well defined. Operation of water-stage recorder satisfactory except for periods of break in record shown in the footnote to daily-discharge table. Daily discharge ascertained by applying to the rating table mean daily gage heights determined by inspection of gage-height graph, or, for days of considerable fluctuation, by averaging the discharge for equal intervals of the day, except March 27 to November 1, 1916 for which discharge was ascertained by use of discharge integrator. Results excellent except for periods of break in record, for which they are fair. Shelockum Lake, at elevation 344 feet, is only 350 acres in area. The drainage basin above the lake is rough and precipitous and is covered with little soil or vegetation. There are no glaciers or ice fields at the source of the tributary streams. Therefore, as there is little natural storage, the run-off after a heavy rainfall is rapid and not well sustained, and during a hot, dry summer the flow becomes very low. The large amount of snow that accumulates during the winter months maintains a good flow. Discharge measurements of Shelockum Lake outlet at Bailey Bay, during the period June 1, 1915, to Dec. 31, 1916: Date. July Aug. 6 Sept. 14 Made by G. H. Canfield. do Gardner and Williams.. Canfield and Hoyt do Gage height. Feet. Discharge. Sec.-ft. Date. Oct. 15 Apr. 18' Made by G. H. Canfield do do Gage height. Feet. Discharge. Sec.-ft. 2 9Rf) a Measurement made from boat at cable section.

MINERAL RESOURCES OF ALASKA, 1916. Daily discharge, in second-feet, of Shelockum Lake outlet at Bailey Bay, for the period June 1, 1915, to Dec. 31, 1916. Day. 1. 2 3 4 5 6 7 3 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Jan. is Feb. 4in Mar. no

4Q Apr. May. Ifi4 37Q June. OEO 3&l AW cno July. in Aug. 13fl Sept. fi4 91 fl oeo Oct. 2,220 1,030 4fi 3io Nov. KT inn Q1 Dec. 3n oc NOTE. June 1-3, discharge estimated; Aug. 8 to Sept. 14, Sept. 21 to Oct. 4, 1915, and July 1-8, 1916, gage clock stopped; discharge estimated from maximum and minimum stages indicated by the recorder and by a comparison of the record for this station with that for Orchard Lake outlet. Jan. 23 to Mar. 13, ice in well; discharge estimated from climatic records at Ketchikan and by a comparison of hydrograph for this station with th:,t for Orchard Lake outlet. Estimates of discharge below 91 second-feet, June 1, 1915, to Feb. 21,1916, difler from that published in Bulletin 642 because of a revision of the rating curve.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 119 Monthly discharge of $helockum Lake outlet at Bailey Bay for 1915-16. [Drainage area, 18 square miles.] Month. July July Discharge in second-feet. Maximum. 2,220 2,220 Minimum. Mean. Per square mile. Run-off. Depth in inches on drainage area. 6.26' Total in acre-feet. 13,900 3,760 7,930 6,010 31,600 24,700 8,690 6,520 1,280 6,440 3,420 9,520 17,200 25,200 19,900 11,900 13,800 149,000 15,700 7,260 3,500 26,500 KARTA RIVER AT KARTA BAY, PRINCE OF WALES ISLAND. LOCATION. In latitude 55° 34' N., longitude 132° 37' W., at head of Karta Bay, an arm of Kasaan Bay,"on east coast of Prince of Wales Island, 42 miles by water across Clarence Strait from Ketchikan. DRAINAGE AREA. 49.5 square miles (U. S. Forest Service reconnaissance map of Prince of Wales Island, 1914). RECORDS AVAILABLE. July 1,1915, to December 31, 1916. GAGE. Stevena water-stage recorder on left bank, half a mile above tidewater, at head of Karta Bay and 1£ miles below outlet of Little Salmon Lake. Two per cent of total drainage of Karta River enters between outlet of lake and gage. DISCHARGE MEASUREMENTS. At medium and high stages made from cable across river 50 feet upstream from gage; at low stages by wading at cable section. CHANNEL AND CONTROL. From Little Salmon Lake, 1$ miles from tidewater, the river descends 105 feet in a series of rapids in a wide, shallow channel, the banks of which are low but do not overflow. The bed .is of course gravel and boulders; rock crops out only at outlet of lake. Gage and cable are at a pool of still water formed by a riffle of coarse gravel that makes a well-defined and permanent control. EXTREMES OP DISCHARGE. Maximum stage recorded during period, 4.4 feet, October 16 (discharge, 3,340 second-feet); minimum flow, estimated from discharge measurement, gage record, and climatic data, 21 second-feet, February 11. ICE. Stage-discharge relation affected by ice.

MINERAL RESOURCES OF ALASKA, 1916. ACCURACY. Stage-discharge relation practically permanent, except when affected by ice January 8 to February 16. Rating curve well defined between 80 and 1,500 second-feet; extended below 80 second-feet to the point of zero flow and above 1,500 second-feet by estimation. Operation of water-stage recorder satisfactory except for periods indicated by breaks in record as shown in footnote to daily-discharge table. Daily discharge ascertained by applying to rating table mean daily gage heights determined by inspecting gage-height graph, or for days of considerable fluctuation by averaging results obtained by applying to rating table mean gage heights for regular intervals of day. Results excellent except for periods of break in record, for period affected by ice, and for discharge above 1,500 second-feet, for which they are fair. The combined area of Little Salmon Lake at elevation 105 feet, and Salmon Lake at elevation 110 feet, is 1,600 acres. The slopes along the right shore of lakes and at head of Salmon Lake are gentle, and the area included by the 250-foot contour above lake outlet is 5,500 acres. The drainage area to elevation 2,000 feet is heavily covered with timber and dense undergrowth of ferns, brush, and alders. The upper parts of the mountains are covered with thin soil and brush. Only a few peaks at an elevation of 3,500 feet are bare. This large lake and flat area and thick vegetal cover afford considerable natural storage, which, after heavy precipitation, maintains a good run-off. The snow usually melts by the end of June, and the run-off becomes very low during a dry, hot summer. The Forest Service in summer of 1916 constructed a pack trail from tidewater to outlet of Little Salmon Lake. Discharge measurements of Karta River at Karta Bay during the period July 1 , 1915, to Dec. 31, 1916. Date. July Sept. 7 Oct. 20 Made by G. H. Canfleld do do Can field and Hoyt G. H. Canfleld Gage height. Feet. Discharge. Sec.-ft. 1,500 Date. Jan. 29 Feb. 29 May 18 Made by G. H. Canfleld do do Gage height. Feet. ol.45 Discharge. Sec.-ft. a Stage-discharge relation affected by ice. Daily discharge, in second-feet, of Karta River at Karta Bay for the period July 1,1915, to Dec. 31, 1916. Day. 1. 2 3 4 5 6 7 8 g 10 11 12 13 14 15 July. Aug. 44* 1,200 1,080 1,170 1,170 1,130 Sept. Oct. 1,000 2,120 Nov. 1,920 1,340 1,000 1,000 1,090 1,680 1,400 Dec. 1,020 1,330 1,540 1,330 1,390 1,980 1,860 1,100 Day. 16 17 18 19 20 21 22. 23 24 25 26 27 28 29 30 31 July. 7fi Aug. Sept. Oct. 1,960 1,240 1,150 1,490 1,310 1,010 1,000 1,050 1,170 1,170 1,620 l'050 1,350 Nov. Dec. 31 iT\ fi7Q

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 121 Daily discharge, in second-feet, of Karta River at Karta Bay for the period July J, 1915, to Dec. 31, 1916 Continued. Day. 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Jan. Feb. 9QQ 9V? Mar. 1Q7 Apr. 1,510 1,370 1,000 May. June. July. Aug. Sept. Oct. 1,680 1,450 Nov. 1,370 1,480 1,120 1,000 Dec. 1,010 NOTE. Discharge July 1-15,1915; estimated at 95 second-feet from one discharge measurement and from a comparison of hydrograph for this station with that for Fish Creek. Discharge Jan. 8 to Feb. 16, 1916. estimated because of ice; Sept. 1-6, Sept. 23 to Oct. 18,1915, May 17 and May 30 to June 14,1916, estimated because of clock stopping, from maximum and minimum stages indicated by recorder and from a comparison of record for this station with that for Fish Creek. Monthly discharge of Karta River at Karta Bay for the period July 1, 1915, to Dec. 31, [Drainage area, 49.5 square miles.] Month. July September October. . March ... April May ... . June July October. The period Discharge in second-feet. Maximum. 1,200 3,000 1,920 1,980 1,510 3,000 1,680 1,480 1,010 Minimum. Mean. 1,020 Per square mile. Run-ofl. Depth in inches on drainage area. Total in acre-feet. 5,070 23,500 13,500 42, 100 48,900 45,000 5,630 14,100 12,500 37,400 30,400 28,600 17,000 10,200 16, 700 329, 000 29,800 41,500 23, 700

MINERAL RESOURCES OF ALASKA, 1916. MILL CREEK NEAR WRANGELL. LOCATION. In latitude 56° 28' N., longitude 132° 12' W., near outlet of Lake Virginia on east shore of Eastern Passage, a narrow channel between Wrangell Island and mainland, 6 miles by water from Wrangell. DRAINAGE AREA. 50' square miles (measured on U. S. Coast and Geodetic Survey chart 8200). RECORDS AVAILABLE. June 17, 1915, to December 31, 1916. GAGE. Stevens water-stage recorder on left bank one-fourth mile below Lake Vir-. ginia and three-fourths mile above tidewater. DISCHARGE MEASURHMENTS. Made from cable across creek, 10 feet upstream from gage. CHANNEL AND CONTROL. From the outlet of the lake, at an elevation of 100 feet above sea level and at a distance of 1 mile from tidewater, the creek descends in a series of rapids and falls. The bed is glacial drift and boulders at the rapids and rock outcrop at points of concentrated fall. The gage is in a pool of still water created by a small fall at a contracted point of channel. This fall makes a well-defined, permanent, and sensitive control. EXTREMES OF DISCHARGE. Maximum stage recorded during period, 8 feet October 16,1915 (discharge, computed from extension of rating curve, about 3,310 secondfeet, differs from that published in Bulletin 642 because of revision of rating curve); minimum stage recorded, 0.02 foot February 11 (discharge, 15 secondfeet). ICE. Ice forms on the lake, at gage, and along the banks, but the swift current and flow of relatively warm water from the lake keeps the control open. ACCURACY. Stage-discharge relation permanent; not affected by ice. Rating curve well defined below 1,200 second-feet; extended above 1,200 second-feet. Operation of water-stage recorder satisfactory except for periods indicated in footnote to daily-discharge table. Daily discharge ascertained by applying to the rating table mean daily gage heights determined by inspecting gage-height graph, or, for days of considerable fluctuation, by averaging results obtained by averaging discharge for equal intervals of the day. Results good except for periods when water-stage recorder was not operating satisfactorily. The drainage basin is covered with a heavy stand of timber to an elevation of 2,500 feet and a dense undergrowth of ferns, brush, alders, and devil's club, but because of the steep slopes and thin soil the run-off after heavy rains is rapid and the ground storage is small. During a dry, hot period in summer the flow is augmented by melting ice from glaciers at the headwaters of two of the tributary streams. Discharge measurements of Mill Creek near Wrangell during the period June 17, 1915, to Dec. 31,1916. Date. July Nov. 3 Made by do G. H. Canfield Gage height. Feet. 2 on Discharge. Sec.-ft. Date. Feb. m Sept. 21 Made by G.H.Canfield. do do Gage height. Feet. Discharge. Sec.-ft. 1,060 o Ice at gage; control open. i Revised since last published.

WATEE-POWER INVESTIGATIONS IN SOUTHEASTEB.N ALASKA. 123 Daily discharge, in second-feet, of Mill Creek near Wrangellfor the period June 17,1915, to Dec. 31,1916. I 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 20 27 28 29 30 31 Day. 1.. 2 3 4 5 6 7 8 0 10 11 12 13 14 15 16 17 18 19 20 21 22. 23 24 25 26. 27 28 29 30 31 D Jan. 41' ay. Feb. Mar. Apr. June. SQ7 sdfi May. July Q3 /in 4.1? June. 1,030 4QO 1,240 1,460 1,080 7on 1,010 1,080 ?, ,5 ? J Au ?' ', ? f f l.flV 1,4 fi ft a a a a a uly. 73? 6?8 CQO R50 1?0 44? 5?5

filO g. ?1 ?5 78 ,50 ?0 1? A 1, 1j lj 1, Se 1j 1, 1, ug. m un 9?0 R98 66? 6?s R6? R?8 49? 49? W7 W? WO S10 59? 5?5 4?7 pt. 4?1 49? 40fi ?,68 ?36 ?30 .59? 49? 49? 31? 94? Sej ?, ? 7, Ijl 1,3

W

W Dot. ,240 ,110 jao ,620 ,480 Oct. 1G8 1,220 1,400 9Q4 1,510 1,050 Nov. Nov. ISA iv; Dec. Dec. NOTE. Water-stage recorder not working properly for following periods: Oct. 5 to Nov. 2, 1915; daily discharge estimated from maximum and minimum stages indicated by recorder, from climatic records and comparison with gage-height records for stations in adjacent drainage basins. Dec. 18-21, 1915; discharge interpolated. Oct. 1 to Nov. 2U and Dec. 8-31,191G; discharge estimated from maximum and minimum stages indicated by recorder and by comparison with record for Shelockum Lake outlet as follows: Oct. 23-31. 1,000 second-feet; Nov. 1-19, 253 second-feet; Dec. 8-31, 90 second-feet. Water frozen in well Tan. 23 to Fob. 11,1916; discharge estimated from one discharge measurement and climatic records.

MINERAL RESOURCES OF ALASKA, 1916. Monthly discharge of Mill Creek near Wrangellfor the period June 17, 1915, to Dec. SI, [Drainage area, 50 square'miles.] Month. July February. June July October. Discharge in second-feet. Maximum. 1,910 1,780 2,620 1,460 1,660 1,990 1,370 2,620 1,510 Minimum. o89 o52 Mean. Per square mile.

Run-off. Depth in inches on drainage area. Total in acre-feet. 13,300 27,200 39,700 38,000 118,000 41,300 12,300 10,800 2,400 7,540 3,900 14,600 24,700 48,000 49,700 44,800 38,600 299,000 41,400 14,800 6,080 62,300 a Minimum stage recorded by the water-stage recorder, exact date not known. GEEBN LAKE OUTLET AT SILVER BAY, NEAR SITKA. LOCATION. In latitude 56° 59' N., longitude 135° 5' W., at outlet of Green Lake, at head of Silver Bay, 10$ miles by water south of Sitka. DRAINAGE AREA. Not measured. BECORDS AVAILABLE. August 22, 1915, to December 31, 1916. GAGE. Stevens water-stage recorder on right bank at outlet of lake, reached by trail which leaves the beach one-fourth mile north of mouth of stream, ascends a 600-foot ridge, and then drops down to the outlet of the lake. DISCHARGE MEASUREMENTS. Made from cable across outlet 30 feet below gage. CHANNEL AND CONTROL. From Green Lake, 240 feet above sea level and 1,800 feet from tidewater, the stream descends in a series of falls and rapids through a narrow canyon whose exposed rock walls rise perpendicularly more than a hundred feet. EXTREMES OF DISCHARGE. Maximum stage recorded during period, 10.22 feet at 5 a. m. September 19, 1916 (discharge, computed from extension of rating curve, 2,400 second-feet); minimum flow, estimated from hydrograph for Baranof Lake outlet and climatic records, 24 second-feet February 13. ICE. Ice forms on lake and at gage, but because of current and flow of relatively warm water from the lake the control remains open.

WATER-POWER INVESTIGATION'S IN SOUTHEASTERN ALASKA. 125 ACCURACY. Stage-discharge relation permanent. Eating curve well defined between 100 and 1,300 second-feet. Operation of water-stage recorder satisfactory except for periods indicated by breaks in record, as shown in the footnote to the dailydischarge table. Daily discharge for 1915 and February 15 to March 2 and November 1 to December 27,1916, ascertained by applying to the rating table mean daily gage heights determined by inspecting gage-height graph, or, for days of considerable fluctuation, by averaging results obtained by applying to rating table gage heights for regular intervals of day. Discharge April 3 to October 31, 1916, ascertained by use of discharge integrator. In the fall and winter the flow is low because there is little ground storage and on most of the drainage area the precipitation is in the form of snow. This accumulated snow produces a large run-off during the spring, and the melting ice from the glacier and the ice-capped mountains augment the run-off from precipitation during the summer. The area of Green Lake is estimated to be only 100 acres. Discharge measurements of Green Lake outlet at Silver Bay, near Sitka, during the period Aug. 22, 1915, to Dec. 31, 1916. [Made by G. H. Canfield.] Date. Nov. 22 Dec. 6... Gage height. Feet. Discharge. Sec.-ft. Date. Feb. 16 Oct. 24. Gage height. Feet. Discharge. Sec.-ft. Date. Oct. 24. 24 25 Gage height. Feet. Discharge. Sec.-ft. 1,210 o Tree lodged on control, causing backwater at gage. Daily discharge, in second-feet, of Green Lake outlet at Silver Bay, near Sitka, for the period Aug. 22, 1915, to Dec. 31, 1916. Day. 1. 10 11 12 14 15 Aug. Sept. 1,400 Oct. 1,070 1 non 1,040 1,180 Nov. Dec. Day. 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Aug. Sept. 1,310 1,380 1,010 Oct. Nov. Dec. 103210° 18 Bull. 662 9

MINERAL RESOURCES OF ALASKA, 1916. Daily discharge, in second-feet, of Green Lake outlet at Silver Bay, near Sitka,for the period Aug. 22, 1915, to Dec. 81,1916 Continued. Day. 1 2 3 4 5 6 7 8 9 10 11 ! 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Feb. cu Mar. Apr. May June 1,020 July Aug. 1,310 CIO Sept. 1,880 one Oct. 1,120 Nov. A.SA 14S Dec. J82 to NOTE. Discharge, Aug. 22-31,1915, because of backwater caused by tree lodged on control, computed by applying recorded gage heights reduced by 0.25 foot to rating table. Because of clock stopping or water falling below well, discharge estimated, trom climatic record at Sitka and from comparison of hydrograph for this station with that lor Baranof Lake outlet, as follows: Oct. 17-31,292 second-feet; Nov. 1-20,1915.281 second-feet; Jan. 1-31, 35 second-feet; Feb. 1-13, 24 second-feet; Feb. 14, 40 second-feet; Mar. 3-28, 1916, 45 second-feet. Monthly discharge of Green Lake outlet at Silver Bay, near Sitka, for the period Aug. 22, 1915, to Dec. 31, 1916. Month. August 22-31... July The year. 1916.' Discharge in second-feet. Maximum. 1,400 1, ISO281 1,020 1,310 1,880 1,880 1,120 Minimum. Mean. Run-oft (total in acre-feet). 6,940 34, 100 29,900 11,200 7,260 2,150 4,490 2,850 6,960 17,400 33,800 27,400 30,700 33,600 208,000 29,000 12,500 5,980

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 127 BARANOF LAKE OUTLET AT BARANOF, BARANOP ISLAND. LOCATION. In latitude 57° 5' N., longitude 134° 54' W., at townsite of Baranof, at head of Warm Spring Bay, east coast of Baranof Island, 18 miles east of Sitka across island, but 96 miles from Sitka by water through Peril Strait. DRAINAGE AREA. Not measured. RECORDS AVAILABLE. June 28, 1915, to December 31, 1916. GAGE. Stevens water-stage recorder on right bank 700 feet below Baranof Lake and 800 feet above tidewater at head of Warm Spring Bay. DISCHARGE MEASUREMENTS. Made from cable across stream 100 feet below lake and 600 feet above gage. CHANNEL AND CONTROL. From Baranof Lake, at elevation 130 feet above sea level, and 1,500 feet from tidewater, the stream descends in a series of rapids and small falls and enters the bay in a cascade of about 100 feet concentrated fall. The bed is of glacial drift, boulders, and rock outcrop. The gage is in an eddy 50 feet downstream from the foot of a small fall and 100 feet upstream from a riffle which forms a well-defined control. EXTREMES OF DISCHARGE. Maximum stage recorded during period, 5.3 feet August 10, 1915 (discharge, computed from extension of rating curve, 3,350 second-feet); minimum flow estimated by discharge measurement and climatic data, 28 second-feet on February 13. ICE. Because of the swift current and flow of relatively warm water from the lake, the stream remains open. DIVERSIONS. The flume to Olsen's sawmill diverts from the stream 200 feet below gage only sufficient water to operate a 25-horsepower Pelton water wheel. ACCURACY. Stage-discharge relation permanent, not affected by ice. Rating curve well defined below 2,000 second-feet. Operation of water-stage recorder satisfactory except for short periods indicated in footnote to daily-discharge table. Daily discharge ascertained by applying to rating table mean daily gage heights determined by inspecting gage-height graph, or, for days of considerable fluctuation, by averaging discharge for equal intervals of day. Results good except for periods when recorder did not operate satisfactorily, and for periods when water was frozen in well, for which they are fair. The drainage area is rough and precipitous, and the vegetable and soil cover is thin, even on the foothills of the mountains. The run-off is rapid, and the ground storage is small. During a dry, hot period, however, the flow is greatly augmented by melting ice from several small glaciers and ice-capped mountains. Discharge measurements of Baranof Lake outlet at Baranof during the period June 28, 1915, to Dec. SI, 1916. Date. Sept. 4 rjec y Made by Canfleld and Peterson.. Canfleld and Gardner . . do G.H. Canfleld. Gage height. Feet. Discharge. See.-ft. 1,700 Date. Feb. 13 May 23 Made by G.H. Canfleld do Gage height. Feet. Discharge. Sec.-ft.

MINERAL RESOURCES OF ALASKA, 1916. Daily discharge, in second-feet, of Baranof Lake outlet at Baranoffor the period June 28, 1915, to Dec. 31, 1916.' 1. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Day. 1. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 :... 24 25 26 27 28 29 30 31 Daj Jan. r. Feb. Mar. Apr. June. May. Q7fl My

1,10 1,48 1,05 June. 1,050 1,010 1,050 1,230 1,480 1,480 1,280 1,050 n s f) f)

J Au§ 6,

uly.

itt R7 IX) rto A i, Sej 1, 1, 1, 1.i.i, ng791 a5i a56 a56 lull 3t. WO DOO fvtO filfi R15 UA. Sei a a a fi f

F F i,s ff f ff l.f f )t. :09 WO BO >32 86 >95 Ct. WO 92fi Oct 2fl 4? M 6? 6? 8fl 4f fif 8P 7f= 5? 8? 7f 6f 6f 6T 4f 3,' t) rf> LA fi ,0 rf) ,8

Kl /) Nov. 9Q1 Dec. Dec. no NOTE. Discharge estimated for following periods, because of unsatisfactory operation of water-stage recorder: Aug. 11-13 (mean discharge, 886 second-feet), and Sept. 1-3,1915, by comparison with records of flow for streams in adjacent drainage basins, and from minimum stage for period indicated by recording pencil; Jan. 20 to Feb. 13 from climatic records and discharge measurement of Feb. 13; Apr. 12-17 by comparison with record of flow for Green Lake outlet; May 21 and 22,1916, interpolated.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 129 Monthly discharge of Baranof Lake outlet at Baranof,for the period of July 1,1915, to Dec. 31, 1916. Month. July August. The period. April May July October. The period. Discharge in second-feet. Maximum. 1,480 3,000 1,480 1,050 1,480 1,010 1,850 1,850 Minimum. Mean. Run-off (total in acre-feet). 46,700 56,000 38,800 142,000 35,200 14,600 12,200 2,470 3,180 2,600 9,580 27,700 47,800 41,400 37,200 4JO,300 274,000 32,200 17,900 6,110 56,200 SWEETHEART FALLS CREEK NEAR SNETTISHAM. LOCATION. In latitude 57° 56' N., longitude 133° 41/ W., on east shore 1 mile from head of south arm of Port Snettisham, 3 miles south of mouth of Whiting River, 7 miles by water from Snettisham, and 42 miles by water from Juneau. No large tributaries enter river between gaging station and outlet of large lake, 2$ miles upstream. DRAINAGE AREA. 27 square miles (measured on the United States Geological Survey topographic map of the Juneau gold belt, edition of 1905). RECORDS AVAILABLE. July 31, 1915, to December 31, 1916. GAGE. Stevens water-stage recorder on right bank 300 feet upstream from tidewater on east shore of Port Snettisham. DISCHARGE MEASUREMENTS. Made from cable across river one-fourth mile upstream from gage. CHANNEL AND CONTROL. From the outlet of lake at an elevation of 520 feet above sea level and 2£ miles from tidewater, the river descends in a series of rapids and falls through a narrow, deep canyon. Gage is in a pool at foot of two falls, each 25 feet high, which are known as Sweetheart Falls; outlet of pool is a natural rock weir, which forms a well-defined and permanent control for gage. EXTREMES OP DISCHARGE. Maximum stage recorded during period, 4.2 feet August 14, 1915 (discharge, computed from an extension of the rating curve, 1,420 l second-feet); minimum flow, estimated from discharge measurement and climatic data, 15 second-feet February 11. ICE. Stage-discharge relation not seriously affected by ice. Differs from that published in Bulletin 642 because of a revision of rating curve.

MINERAL RESOURCES OF ALASKA, 1916. ACCURACY. Stage-discharge relation, practically permanent; affected by ice January 19 to February 22. Rating curve well defined between 80 and 1,300 second-feet; extended beyond these limits by estimation. Operation of water-stage recorder satisfactory except for periods indicated by breaks in record, as shown in footnote to daily-discharge table. Daily discharge ascertained by applying to rating table mean, daily gage heights determined by inspecting gage-height graph, or for days of considerable fluctuation by averaging results obtained by applying to rating table gage heights for regular intervals of day. Results excellent except for periods of break in record and for stages below 80 and above 1,300 second-feet, for which they are fair. In the fall and winter the run-off is small because the precipitation is in the form of snow and because of the small amount of ground storage; during a hot, dry period the low run-off from the ground and lake storage is augmented by melting ice from one glacier. Discharge measurements of Sweetheart Falls Creek near Snettisham during period July 31, 1915, to Dec. 31, 1916. [Made by G. H. Canfield.] Date. July 31... Ancr 9Q Nov.13. Dec. 14 Gage height. Feet. 1 4Q Discharge. Sec.-ft. Date. Feb. 5 Oct. 13 Gage height. Feet. o0.33 Discharge. Sec.-ft. 1,240 Date. Oct. 14. Nov. 12 Gage height. Feet. Discharge. Sec.-ft. QQfi o Stage-discharge relation affected by ice. Daily discharge, in second-feet,- of Sweetheart Falls Creek near Snettisham for the period Aug. 1, 1915, to Dec. 31, 1916. Day. 10 11 12 13 14 15 Aug. 1,220 1,330 1,220 Sept. Oct. 1,070 Nov. Dec. 14ft Day. 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Aug. 1,070 ?4.n Sept. 1,090 Oct. Nov. Dec.

WATEE-POWEB INVESTIGATIONS IN SOUTHEASTERN ALASKA. 131 Daily discharge, in second-feet, of Sweetheart Falls Creek near Snettisham for the period Aug. 1, 1915, to Dec. 31, 1916 Continued. Day. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Jan. 4Q Feb. 1Q 1O fi4 Mar. 3O Apr. May. WM 1Q9 91 n 9V> 4/13 June. 1,030 1,120 1,010 1,070 1,070 1,020 July. Aug. Sept. 9QA 1H "5 SI'5 7fin SOS 1,090 1,040 73ft Oct. OKK 1,220 1,000 1,200 1,190 A44 Nov. 9HQ inn

31 ft 15H 1 Qrt Dec. Q4 discharge estimated from climatic record at a with those for Long River and Mill Creek: Nov. 5-11,1915, Jan. 19 to Feb. 13 andHar. 18-22, Dec. 25, 26, and 29,1916, daily discharge; Fob. 14-22, 64 second-feet; Mar. 24-31, 55 second-feet; Apr. 1-12,152 second-feet; July 19-31, 505 second-feet; and Aug. 1-25. 1916, 604 second-feet. Discharge, Aug. 1 to Oct 19, 1915, above 335 second-feet, differs from that published in Bulletin 642, because of a revision of the rating curve, based on highwater measurements obtained in 1916. Monthly discharge of Sweetheart Falls Creek near Snettisham for the period Aug. 1, 1915, to Dec. 81.1916. [Drainage area, 27 square miles.] Month. September April May July The year . Discharge in second-feet. Maximum. 1,330 1,090 1,070 1,120 ol,180 l!090 1,120 1,220 Minimum. Mean. Per square mile. Run-off. Depth in inches on drainage area. Total in acre-feet. 30,800 31,200 25,300 10,000 6,210 2,360 2,190 2,640 9,280 22,600 46,800 30,800 35,800 37,800 232,000 38,200 11,500 5,390 55,100 a Maximum stage indicated by water-stage recorder; exact date not known.

' MINERAL RESOURCES OF ALASKA, 1916. CRATER LAKE OUTLET AT SPEEL RIVER, PORT SNETTISHAM. LOCATION. At outlet of Crater Lake, 1 mile upstream from the edge of tide flats at head of north arm of Port Snettisham, 2 miles by trail from cabins of Speel River Project (Inc.), which are 42 miles by water from Juneau. DRAINAGE AREA. 11.9 square miles (measured on topographic maps of the Alaska Boundary Tribunal, edition of 1895). RECORDS AVAILABLE. January 23, 1913, to December 31, 1916. GAGE. Stevens water-stage recorder on left shore of lake, 100 feet upstream from outlet. A locally-made water-stage recorder having a natural vertical scale and a time scale of 1 inch to 24 hours was used 'until replaced by Stevens gage June 29, 1916. The gage datum remained the same during the period. During the winter months, because of inaccessible location and deep snow, the operation of the gage at the lake was discontinued, and the stage read at staff gage in channel exposed at low tide at beach. The first gage at beach was set at an unknown datum and washed out in winter of 1915-1916. Another staff gage was set at about the same location and used after November 24, 1916. DISCHARGE MEASUREMENTS. Made from cable across outlet of lake, 100 feet downstream from gage and 10 feet upstream from crest of first falls. The rope sling from which discharge measurements were first made was replaced in fall of 1915 by a standard United States Geological Survey gaging car, making more accurate measurements possible. CHANNEL AND CONTROL. The gage is on left shore of lake, 100 feet upstream from outlet where the stream becomes constricted into a narrow channel, the bed of which is composed of large boulders and rock outcrop, which form a well-defined and permanent control. EXTREMES OF DISCHARGE. Maximum stage during the period, 5.9 feet, August 13, 1915 (discharge, estimated from extension of rating curve, 1,680 second-feet); minimum flow, 5 second-feet, February 1 to 13,1916, estimated from one discharge measurement and climatic records. ACCURACY. Stage-discharge relation permanent. Rating curve defined by 19 discharge measurements, 13 of which were made by employees of the Speel River Project (Inc.) and 6 by an engineer of the United States Geological Survey, and is well defined below and extended above 1,000 second-feet. Rating curve used November 24 to December 31, 1916, for staff gage at beach, fairly well defined. Operation of water-stage recorder used during 1914 and 1915 not satisfactory because of slippage of float cord and unfavorable time and gage-height scales. Errors from these sources probably compensating in computation of monthly mean discharge. Operation of Stevehs water-stage recorder satisfactory except September 1 to 28, 1916, when it stopped. Daily discharge for 1913, except as indicated in note to daily-discharge table, is the result of discharge measurements made nearly every day by float or current meter and was furnished by the Speel River Project (Inc.). Discharge record January 1 to May 2, December 1 to 31, 1914, and January 1 to April 20, 1915, computed from gage-height records for staff gage at beach and furnished by the Speel River Project (Inc.). Daily discharge May 3 to November 30, 1914, and April 21 to November 25, 1915, ascertained by engineers of the United States Geological Survey by applying to rating table mean daily gage heights furnished by Speel River Project (Inc.). Daily discharge July to November, 1916, ascertained by applying to rating table mean daily gage heights determined by inspecting gage-height graph, and December 9 to 23, 1916, from occasional readings of staff gage at beach. Results good for records obtained from gage at lake; other records probably fair. Crater Lake is at an elevation of 1,010 feet .above sea level and covers 1.1 square miles. The sides of the mountains surrounding the lake are steep and barren and the tops are covered by glaciers.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 133 Discharge measurements of Crater Lake outlet at Speel River during the period Oct. 13, 1914, to Dec. 31,1916. Ddte. Oct. 13 Nov. 19 May 21 June 21 Aug. 3 Made byKennedy and Peterson. Lindsay and Peterson.. G. H.Canfleld. Gage height. Feet. 1 4K Discharge. Sec.-ft. Date. Feb. May 10 July Aug. 11 Oct. 17 Nov. 17 Dec. 12 Made by G. H.Canfleld do do.. .. do do G. H.Canfleld do do do Gage height. Feet. C°) ol.!9 Discharge. Sec.-ft, a Measurement made at tidewater flats. Gage height referred to temporary gage; datum unknown. Daily discharge, in second-feet, of Crater Lake outlet at Speel River for the period Jan. 23, 1913, to Dec. 31, 1916. Day. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Jan. Feb. o55 o42 o49 o60 o29 Mar. o76 Apr. a 40 ft4 May. June. 377o400 July. o840 o860 1,100 1,100 -Aug. 1,100 1,100 1,220 1,120 1,100 1,100 1,070 1,100 1,330 1,390 1,110 1,010 Sept. o460 o500 o450 o500 Oct. o350 ol80 ollO o 90 o80 o750 1,400 Nov. o98 ol46 ol80 o200 o!70 o!40 ollO o80 o80 o70 60 o50 a 40 Dec. o65 a Estimated.

MINERAL RESOURCES OF ALASKA, 1916. Daily discharge, in second-feet, of Crater Lake outlet at Speel River for the period Jan. 1913, to Dec. 31,1916 Continued. Day. 1. 2 3 4 5 6 7 S.. 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26. 27 28 29 30 31 Day. 1. 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 9fi 27 28 30 j£ Jai m. B7 2fi ?fi ?6 Bft W fi fi fi ] Feb ?eb. ?4 T

OK 9fi ' S9 S9 62

Mar. Apr. in Apr. May. I3n May. June. June J fi 9, ft ft ft fi uly. 4?,9 69?, Jul ? fi fi fi A 0?, R2 ft?, ug. Ai I, Sei ? Jg429 ?,78 Dt. S Oct 4? 4? 2? 2? ept. 62fi 2fi1 fift?, Nov. Oct. Dec. Nov.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 135 Daily discharge, in second-feet, of Crater Lake outlet atSpeel River for the period Jan. 28, 1913, to Dec. 81, 1916 Continued. Day. July. Aug. HI 7 Sept. Oct. QQfi Nov. Dec. 9Q Day. July. Aug. Sept. Oct. IV) HI 7 Nov. 7S fift Dec. <?Q 4?, QQ 9Q

NOTE. Discharge estimated by comparison with records of flow for streams in adjacent drainage basins as follows: July 2-7, 750 second-feet; July 26-31,1913, 800 second-feet; Oct. 9-12,1914, 150 second-feet; and Nov. 26-30,19i5, 32 second-feet. No gage-height record available Nov. 26,1915, to June 30,1916. Monthly discharge of Crater Lake outlet at Speel River for the periods Feb. 1,1913, to Nov. 80, 1915, and July 1 to Dec. 81, 1916. [Drainage area, 11.9 square miles.] Month. March... . April June July August. The period. October. April May July September. March . April May July The year Discharge in second-feet. Maximum. 1,100 1,400 1,680 Minimum. Mean. Per square mile. Run-off. Depth in inches on drainage area. 250.28' Total in acre-feet. . 2, 610 2,970 3,410 12, 500 31,600 51,000 52, 800 29,200 186,000 16,000 6,430 2,350 1,290 2,500 2,260 3,140 8,850 16, 200

MINERAL RESOURCES OF ALASKA, 1916. Monthly discharge of Crater Lake outlet at Speel River for the period Feb. 1,1913, to Nov. 30, 1915, and July 1, to Dec. 31, 1916 Continued. Month. July Discharge in second-feet. Maximum. Minimum. Mean. Per square mile. Run-off. Depth in inches on drainage area. Total in acre-feet. 11,400 2,670 22,800 28,500 28,000 16, 600 3,050 2,010 LONG LAKE OUTLET NEAR PORT SNETTISHAM. LOCATION. At outlet of Long Lake, 5 miles upstream from mouth of Long River; 2 miles by trail and .water across Second Lake from cabins of the Speel River Project (Inc.), which are at head of north arm of Port Snettisham and 42 miles by water from Junoau. DRAINAGE AREA. 31-9 square miles (measured on topographic maps of the Alaska Boundary Tribunal, edition of 1895). RECORDS AVAILABLE. January 23, 1913, to November 10, 1915. GAGE. Lietz 7-day graph, water-stage recorder on left shore in still water of lake 30 feet upstream from crest of falls in left channel of outlet. Vertical movement of float in a tank set at lake edge transmitted, by system of pulleys and counterpoise, to gage in house 15 feet back from bank. DISCHARGE MEASUREMENTS. At all stages made, with meter on rod, from log footbridge across left channel and suspension footbridge across right channel. Measuring section poor because of rough bed, swift current, and large angle which direction of current makes with measuring section. CHANNEL AND CONTROL. The outlet from lake consists of two narrow channels separated by a small island. The bed, which consists of rock ledge and large boulders at measuring section about 30 feet below gage, breaks off abruptly into high falls. Control permanent. EXTREMES OP DISCHARGE. Maximum discharge during the periods of records, 4,250 second-feet, October 20, 1913; minimum flow, 32 second-feet, several days in January and February, 1914. ICE. Stage-discharge relation not affected by ice. ACCURACY. Stage-discharge relation permanent. Rating curve defined by 9 discharge measurements, 5 of which were made in 1914 by employees of the Speel River Project (Inc.), and 4 in 1915 and 1916 by an engineer of the United States Geological Survey, and is fairly well defined between 30 and 1,800 second-feet. The gage was operated, daily gage heights determined and furnished by the Speel River Project (Inc.). Daily discharge was ascertained by applying gage heights to rating table. Results fair except below 150 second-feet and above 1,500 second-feet, for which they are poor. Because gage could not be operated during the winter and because satisfactory measurements of discharge could not be mad eat high stages, this gaging station was replaced by another one installed on Long River below outlet of Second Lake on November 11, 1915.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 137 Long Lake is 808 feet above sea level and covers 3.1 square miles. The sides of mountains surrounding lake are steep and barren, and the tops are covered with glaciers. Discharge measurements of Long Lake outlet at Port Snettisham, during the period Jan. 30, 1914, to Dec. 31, 1916. Date. Jan. 30 Oct. 14 Made by Gust Grosseth. do Gage height. Feet. Discharge. Sec.-ft,. 1,160 Date. July 15 Nov. 16 Made by G. H.Canfield. do do do Gage height. Feet. Discharge. Sec.-ft. NOTE. Results of measurements in 1914 furnished by Speel River Project (Inc.), Juneau. Daily discharge, in second-feet, of Long Lake outlet at Port Snettisham, for the period Jan. 23, 1913, to Nov. 10, 1915. Day. 2 3 4 5 6 7 8 910 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 Tan. in on Feb. olio a76 1QQ Qfi QA Mar. ol20 o290 1Qfi ollO OQO QQ o76 *7Q o83 o80 Apr. QQ olOO olOO QQ olOO 1TO May. tu 91 Q 4K1 wo QDQ 1,000 al,000 1,000 June. o900 ol,000 1,000 1,160 1,550 1,530 1,600 1,600 1,600 1,640 1,770 1,770 1,640 July. 1,830 1,340 1,340 1,370 1,370 1,.500 a2,000 2,620 2,620 2 74H 2,740 2,500 2 ocn 2 nQn 1,890 1,830 1,830 1,870 l'830 2,010 1,890 Aug. 1,830 1,370 1,370 1,770 2,080 2,620 2,770 2,090 2,090 1,770 1,640 1,340 1,210 1,210 1,080 1,080 1,080 1,000 i nno 1,000 ol,000 ol.OOO 1,770 2 OQA 2,620 Q7A 3,170 2,670 2,' 190 Sept. 1,770 o840 o600 o700 'o800 o800 1,160 1,370 1,770 2,190 2,410 2,140 1,670 1,360 1,180 1,410 ol,500 1,770 ol, 100 9 fiSd Oct. 2,090 1,370 ol.OOO o400 o300 one aOcft o220

a226

a1) fVl ft o3,600 a3,200 2 Q7ft 1,850 1,610 Oon ol,200 I ftflft Nov. o460 o500 Q1Q o700 o500 o400 34ft *J£1 OQ9 neo 1QQ o!40 14A Dec. 1 8Q 9Q4 ocrt 99O. OUO qso ort/S 1 ifta OR QA on

OQ on a Estimated.

MINERAL RESOURCES OF ALASKA, 1916. Daily discharge, in second-feet, of Long Lake outlet at Port Snettisham, for the period Jan. 23, 1913, to Nov. 10, 1915 Continued. Day. Jan. Feb. Mar. Apr. June. July. Aug. Sept. Oct. Nov. Dec. 1,040 1,140 1,290 1,090 1,290 1,290 1,410 1,950 1,650 1,470 1,410 1,470 1,240 1,040 1,530 1,470 1,650 1,950 1,710 1,290 1,090 1,040 1,190 1,190 1,090 1,090 1,090 1,090 1,190 1,290 1,590 1,830 2,220 1,650 1,350 1,190 1,040 1,090 1,290 1,040 Day. Apr. May. June. July. Aug. Sept. Oct. Nov. 1,040 1,190 1,190 1,040 1,040 1,040 1,040 1,040 1,040 1,040 1,040 1,09.0 1,190 1,240 1,140 1,090 1,090 1,290 1,410 1,530 1,650 1,650 1,530 1,350 1,190 1,090 1,090 1,470 2,080 3,050 3,210 2,650 2,150 1,710 1,240 1,140 9,40 1,530 1,830 1,350 1,040 1,140 1,470 1,190 1,290 1,470 1,140 1,290 1,950 1,590 1,140 1,350 1,140 NOTE. Mean discharge estimated as follows: Feb. 3-8, 1913, 140 second-feet; July 2-8, 1913, 1,500 second-feet.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 139 Monthly discharge of Long Lake outlet at Port Snettisham,for the period Feb. 1,1913, to Nov. 10, 1915. [Drainage area, 31.9 square miles.) Month. July The period... December. April July The year.. October April 18-30. July October Discharge in second-feet. Maximum. 1,000 1,770 2,740 3,170 2,410 4,250 1,040 1,950 2,220 1,190 4,250 1,290 1,190 1,650 3,210 1,950 1,350 Minimum. 1,000 Mean. 1,120 1,900 1,760 1,270 1,150 1,210 1,060 1,100 1,260 1,000 Per square mile. Run-off. Depth in inches on drainage area. Total in acre-feet. 6,660 8,790 7,800 66, 600 117,000 108,000 75,600 70,700 22,300 10,000 3, 070 3,770 5,120 6,600 20, 800 43, 100 74,400 65, 200 37, 400 362,000 34, 100 16,200 7,440 6,030 32, 500 50,000 67,600 77,500 59, 500 31, 200 3,630 LONG RIVER BELOW SECOND LAKE AT PORT SNETTISHAM. LOCATION. One-half mile downstream from outlet of Second Lake, 1 mile downstream from outlet of Long Lake, one-half mile upstream from head of Indian Lake; 2$ miles by trail and boat across Second Lake from cabins of the Speel River project at head of the North Arm of Port Snettisham, 42 miles by water from Juneau. DRAINAGE AREA. 33.2 square miles (measured on sheet No. 12 of the Alaska Boundary Tribunal maps, edition of 1895). RECORDS AVAILABLE. November 11, 1915, to December 31, 1916. GAGE. Stevens water-stage recorder on right bank one-half mile below outlet of Second Lake. DISCHARGE MEASUREMENTS. At medium and high stages made from cable across river at gage; at low stages made by wading one-fourth mile downstream.

MINERAL RESOURCES OF ALASKA, 1916. CHANNEL AND CONTROL. At the gage the channel is deep and the current sluggish; banks are low and are overflowed at extremely high stages; bed smooth except for one large boulder. A rapid, 500 feet downstream, forms a well-defined and permanent control. EXTREMES OF DISCHARGE. Maximum stage recorded during period, 6.55 feet at 7 a. m., September 19 (discharge, 2,340 second-feet); minimum flow estimated from one discharge measurement and climatic data, 23 second-feet, February 13. ICE. Stage-discharge relation affected by ice during January, February, and March. ACCURACY. Stage-discharge relation permanent; affected by ice January 16 to April 2. Rating curve fairly well defined between 50 and 400 second-feet and well defined between 400 and 2,000 second-feet. Operation of water-stage recorder satisfactory throughout the open-water period except for short periods in December, 1915, and January, 1916. Daily discharge ascertained by applying to the rating table mean daily gage heights determined by inspecting the gage-height graph. Results good except for stages below 400 second-feet for which they are fair. The area draining to Long River between Long Lake Outlet and this station comprise only 1.3 square miles, including First Lake and Second Lake. Because this area is at a low altitude and has no glaciers the run-off per square mile from it is greater in the early spring but much less in summer than that from the area above Long Lake, which is partly covered by glaciers. Discharge measurements of Long River below Second Lake at Port Snettisham during the period Nov. 11, 1915, to Dec. 31, 1916. Date. Feb. 4o May 11 July 25 Aug. 10 Made by G. H. Canfield do do do do do do Gage height. Feet. Discharge. Sec.-ft. Date. Oct. 12 Nov. 16 Dec. 15 Made by G.H. Canfield. do do G.H. Canfield.. do Gage height. Feet. 5 OQ Discharge. Sec.-ft. 1,270 o Stage-discharge relation affected by ice on control; ice in gage well prevented operation of float. Daily discharge, in second-feet, of Long River below Second Lake at Port Snettisham for the period Nov. 11,1915, to Dec. 31, 1916. Day. 1.. 2 3 4 5 6 7 8 9 10 Nov. Dec. Day. 1915 Con. 11 12 13 14 15 17 18 19 20 Nov. Dec. Day. 1915 Con. 21 22 23 24 25 26 27 28 29 30 31 Nov. Dec. en Qfi

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 141 Daily discharge,in second-feet, of Long River below Second Lake at Port Snettisham for the period Nov. 11,1915, to Dec. 31, 1916 Continued. Bay. 1 2 3 5 6 7 8 9 10 11 12 13 14 15 16 17 18 20 21 22 23 24 25 26 27. 28 29 31 Jan. Apr. inn 1 1Q May. ion June. 1,040 1,090 1,330 1,460 1,460 1,460 1,230 July. 1,090 1,020 1,460 1,660 1,380 Aug. 1,160 1,110 1,520 1,690 1,380 1,040 1,280 1,600 1,440 1,260 1,600 1,380 1,150 1,060 1,020 Sept. 1,160 1,020 1,690 1,550 1,110 1,180 1,410 2,110 1,630 1,300 1,020 1,060 1,020 Oct. 1,520 1,380 1,180 1,300 Nov. on Dec. NOTE. Discharge estimated from climatic records and comparison with records of flow for streams in adjacent drainage basins and one discharge measurement made Feb. 4, as follows: Dec. 10-20, 1915, 85 second-feet; Jan. 16-31,40 second-feet; Feb. 1-13, 24 second-feet; Feb. 14-29, 70.second-feet; and Mar. 1-31, 50 second-feet. Monthly discharge of Long River below Second Lake at Port Snettisham for the period Nov. 11, 1915, to Dec. 81, 1916. [Drainage area 33.2 square miles.] Month. March April May July The year. Discharge in second-feet. Maximum. 1,660 1,520 2,110 Minimum. Mean. 1,070 1,040 Per square mile. Run-off. Depth in inches on drainage area. Total in acre-feet. 4,320 6,040 3,070 2,840 3,070 7,680 15,600 51,400 62,600 66,800 61,900 37,200 8,630 6,310 315,000 103210° 18 Bull. 662-

MINERAL RESOURCES OF ALASKA, 1916. SPEEL RIVER AT PORT SNETTISHAM. LOCATION. At entrance of canyon one-fourth mile downstream from mouth of Long Eiver, and 8 miles upstream from tide flats and the cabins of the Speel River Project (Inc.), which are at head of north arm of Port Snettisham, and 42 miles by water from Juneau. DRAINAGE AREA. Not measured. RECORDS AVAILABLE. July 1 to December 31, 1916. GAGE. Stevens water-stage recorder 150 feet to the left of the constriction of the river at the entrance of the canyon. The gage is reached from cabins of the "Speel River Project by trail to head of Second Lake, boat across Second Lake, trail to head of Indian Lake, boat across Indian Lake, trail down Long River and Indian River to canyon, and cable across river near entrance of the canyon a total distance of about 7 miles. DISCHARGE MEASUREMENTS. At all stages made from cable having a clear span of 400 feet across river, one-half mile below gage and one-fourth mile below lower end of canyon. CHANNEL AND CONTROL. For several miles above the canyon the river flows in several channels through a wide, flat, sandy valley in which the channels are continually shifting. The river is constricted from a width of 500 feet to 75 feet at entrance of canyon. This constriction of channel and rock outcrop at entrance of canyon form a very sensitive and permanent control. The extreme range in stage is 28 feet. Above a stage of 22 feet part of the flow passes through a secondary channel (the bed of which is rock overgrown with brush) which begins near gage and rejoins main channel at lower end of canyon. Below a stage of about 4 feet water from stream does not reach the well except by seepage through gravel. Stage-discharge relation is therefore not permanent for stages below 4 feet. At the gaging cable the bed of the river is gravel, with one large rock outcrop near middle of stream. The current is very swift and carries a large quantity of sand in suspension. ICE. Ice does not form at control, but so much frost forms in gage shelter and on metal parts of gage that the gage does not operate satisfactorily during the winter. ACCURACY. Stage-discharge relation permanent except for stages below about 1,000 second-feet, when frequent measurements are necessary to estimate the flow. Rating curve fairly well defined between 1,200 and 10,000 second-feet; extended above 10,000 second-feet. Operation of water-stage recorder not satisfactory for periods indicated in footnote to daily-discharge table because of the frequent stopping of clock, owing to the binding of paper-supply roll. Daily discharge ascertained by applying to rating table mean daily gage heights determined by inspecting gage-height graph. Results fair for periods when gage was operating satisfactorily; poor for periods when clock was not running. Discharge measurements of Speel River at Port Snettisham during the period July 1 to Dec. 31, 1916. Date. July 12 Aug. 16 Oct. 12 Made by G.H.Canfleld. do G.H.Canfleld do Gust Grosseth. Gage height. Feet. Discharge. Sec.-ft. 5,020 5,860 4,870 6,350 9,140 2,660 Date. Oct. 30 Nov. 8 Dec. 20 Made by do G.H.Canfleld do Gust Grosseth. Gage height. Feet. Discharge. Sec.-ft. 1,340 1,580

WATEB-POWEE INVESTIGATIONS IN SOUTHEASTERN ALASKA. 143 Daily discharge, in second-feet, of Speel River at Port Snettisham for the .period July 1 to Dec. 31,1916. Day. 2. 10 11 12 13 14 15 My. 4,980 Aug. 6,360 5,220 5,060 4,980 5,220 5,570 5,660 5,220 4,980 5,300 5,750 8,190 11,200 11,700 7,040 Sept. 6,360 5,950 4,620 5,220 6,050 4,690 4,310 4,430 10,500 7,790 5,850 5,390 6,250 5,300 Oct. 2,680 7,530 6,580 5,570 5,750 Nov. 1,490 Day. 16 17 18 19 20. 21 22. 23 24 25 26 27 28 29 30 31 July. 5,140 5,480 5,300 A osn 4,900 4,760 4,430 4,130 4,130 4,690 5,570 6,250 6,920 9,200 8,750 7,530 Aug. 5,220 4,370 4,010 5,140 7,160 10,700 8,330 8,610 11,400 10,100 9,660 8,050 7,920 7,400 6,580 6,360 Sept. 5,060 5,750 10,300 12,600 Oct. 4,070 2,900 2,680 3,230 Nov. 1,420 1,420 1,320 1,250 NOTE. Discharge estimated by comparison with records of flow for streams in adjacent drainage basins, as follows: July 1-14, 5,070 second-feet; Sept. 20-30, 5,920 second-feet; Oct. 1-10, 1,560 second-feet; Oct. 8-23, 3,370 second-feet; Oct. 26-31, 2,130 second feet; Nov. 1-13, 612 second-feet; Nov. 20-30, 680 secondfeet; and Doc. 1-31, 420 second-feet. Monthly discharge of Speel River at Port Snettisham for the period July 1 to Dec. 31,1916. Month. July Discharge in second-feet. Maximum. 9,200 11,700 12,600 7,530 Minimum. 4,130 4,010 Mean. 5,420 7,050 6,220 2,890 Hun-off (total in acre-feet). 333,000 433,000 370,000 178, 000 45, 200 25,800 1; 380,000 GRINDSTONE CREEK AT STEPHENS PASSAGE. LOCATION. On north shore of Stevens Passage between Point Bishop and Point Salisbury, one-fourth mile west of mouth of Rhine Creek and 11 miles by water from Juneau. DRAINAGE AREA. Not measured. RECORDS AVAILABLE. May 6 to December 31, 1916. GAGE. Stevens water-stage recorder on left bank, 200 feet from tidewater, installed September 16. A Lietz seven-day graph water-stage recorder was used May 6 to June 17. DISCHARGE MEASUREMENTS. At all stages made by wading either in the channel on the beach, which is exposed at low tide or 100 feet below gage at high tide. CHANNEL AND CONTROL. For a distance of one-fourth mile from tidewater the stream descends in a series of rapida and falls through a narrow rocky channel. The gage is at upper end of a turbulent pool between two falls, the lower of which forms a well-defined control. When gage was installed, logs were jammed in channel near upper end of pool. EXTREMES OP DISCHARGE. Maximum stage recorded during periods of record, 4.95 feet at 9 a. m September 10 (discharge, about 416 second-feet); minimum stage recorded, 0.25 foot during period December 12-31, exact date not known (discharge, 11 second-feet).

MINERAL RESOURCES OF ALASKA, 1916. ICE. Stage-discharge relation not affected by ice. ACCURACY. Stage-discharge relation not permanent because logs occasionally lodged on the control and were washed away during high water. Discharge measurements made during the period May 6 to September 6 indicate that there was no material change at the control. On September 10 logs evidently lodged on the control. When they were cut loose on September 30, the water surface fell 0.2 foot, after which the discharge measurement indicated that the stage-discharge relation was the same as that before September 6. Additional logs were washed away by the high water October 12, after which there was no further change at the control. Rating curve used May 6 to June 16 and September 6 to October 11, fairly well defined between 18 and 80 second-feet; 0.2 foot was subtracted from gage heights September 10 to 29 before applying to rating table. Rating curve used October 12 to December 11 well defined between 10 and 120 second-feet. Operation of Lietz gage not satisfactory because clock lost about 12 hours each week; operation of Stevens gage satisfactory except December 12 to 31, when paper stuck to guides. Daily discharge ascertained by applying to rating table mean daily gage heights determined by inspecting gage-height graph. Results below 10"0 second-feet fair; above 100 second-feet poor. Discharge measurements of Grindstone Creek at Stephens Passage during the period May 6 Dec. 31. 1916. Date. Q Sept. 6 Made by do do : do Gage height. Feet. Discharge. Sec.-ft. Date. Oct. 20 Nov. 24 Made by G.H.Canfleld. do Brown and Canfleld. .. . Gage height. Feet. Discharge. Sec.-ft. Oft

Daily discharge, in second-feet, of Grindstone Creek at Stephens Passage for 1916. Day. May. June. Sept. Oct. Nov. Dec. Day. May.' June. Sept. Oct. Nov. ] A1 9Q Dec. NOTE. Discharge Dec. 12-31 estimated at 15 second-feet by comparison with records of flow for Carlson, Sheep, and Gold creeks. No record June 17 to Sept. 5.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 145 Monthly discharge of Grindstone Creek at Stephens Passage for 1916. Month. May 6-31.. September 6-30. Discharge in second-feet. Maximum. Minimum. Mean. Run-off (total in acre-feet). 2,010 2,680 3,590 4,890 1,740 CARLSON CREEK AT SUNNY COVE. LOCATION. At Sunny Cove on west shore of Taku Inlet, 20 miles by water from Juneau. DRAINAGE AREA. 22.26 square miles (determined by engineering department of Alaska Gastineau Mining Co. from surveys made by that company). RECORDS AVAILABLE. July 18 to December 31, 1916. GAGE. Stevens water-stage recorder on left bank, 2 miles from tidewater; inspected several times a week by employees of the Alaska Gastineau Mining Co. DISCHARGE MEASUREMENTS. At high stages, made from cable across river one-half mile downstream from gage; at medium and low stages, by wading 500 feet upstream from gage. CHANNEL AND CONTROL. Above the gage the stream meanders in one main channel and several small channels through a flat, sandy basin about a mile long; just below gage channel contracts and stream passes over rocky falls that form a welldefined and permanent control. Point of zero flow, gage height 1.5 feet. EXTREMES OF DISCHARGE. Maximum stage recorded during period, 6.15 feet September 18 (discharge, computed from an extension of rating curve, 2,850 secondfeet); minimum stage, 0.53 foot November 13 (discharge, 58 second-feet.) ICE. Stage-discharge relation affected by ice in January and February. ACCURACY. Stage-discharge relation permanent. Eating curve well defined between 90 and 1,200 second-feet, extended below 90 second-feet'to point of zero flow and above 1,200 second-feet by estimation. Operation of water-stage recorder satisfactory except for a few days; as gage was visited several times a week, breaks in record caused by clock stopping were short. Daily discharge ascertained by applying to rating table mean daily gage heights determined by inspecting gage-height graph, or, for days of considerable fluctuation by averaging results obtained by applying to rating table mean gage heights for regular intervals of the day. Results good except for stages below 90 second-feet and above 1,200 second-feet for which they are fair. Discharge measurements of Carlson Creek at Sunny Cove during the period July 18 to Dec. 31, 1916. Date. July 22 Sept. 5 Made by do do Gage height. Feet. Discharge. Sec.-ft. Date. Oct. Nov. Made by 0. H.Canfield do Canfield and Perkins... do Gage height. Feet. Discharge. Sec.-ft.

MINERAL RESOURCES OP ALASKA, 1916. Daily discharge, in second-feet, of Carlson Creek at Sunny Cove for the period July 18 to Dec. 81, 1916. Day. July. Aug. Sept. 1,400 Oct. 1,430 Nov. ' 58 Dec. Day. July. 1,670 1,050 Aug. Sept. 1,540 1,310 Oct. Nov. Dec. 4>; Monthly discharge of Carlson Creek at Sunny Cove for 1916 [Drainage area, 22.26 square miles.] Month. July 18-31.. Discharge in second-feet. Maximum. 1,670 1,540 1,430 Minimum. Mean. Per square mile. Run-off. Depth in inches on drainage area. Total in acre-feet. 16,800 32, 800 38, 100 28,000 7,260 3,600 127,000 SHEEP CREEK NEAR THANE. LOCATION. At lower end of flat basin, above diversion dam for flume leading to Tread well power house at beach, and 1 mile by tramway and ore railway from Thane. DRAINAGE AREA. 4.57 square miles above gaging bridge (measured on United States Geological Survey map of Juneau and vicinity, edition of 1917). RECORDS AVAILABLE. July 26 to December 31, 1916. GAGE. Stevens water-stage recorder on right bank at pool formed by an artificial control just below small island three-tenths mile upstream from diversion dam. Recorder inspected once a week by an employee of the Alaska Gastineau Mining Co. DISCHARGE MEASUREMENTS. At extremely high stages made from gaging bridge two-tenths mile downstream from gage; at low stages made by wading near bridge section. No streams enter between gage and measuring section but seepage inflow varies from a small amount to 10 per cent of total flow, the per cent of inflow usually being large after periods of heavy precipitation. CHANNEL AND CONTROL. The station is near lower end of flat basin through which the stream meanders in a channel having low banks and bed of sand and gravel. An artificial control was built 2 feet below intake for gage well to confine the flow in

WATEE-POWEE INVESTiGATl6isrS IN SOUTHEASTERN ALASKA. 147 one channel during high water and to insure a permanent stage-discharge relation. The spillway of the control at low stages consists of a timber, 16 feet long, set in the bed of the stream. During medium and high stages another timber, 8 feet long, bolted at top near right end, forms part of the control. A 3-foot cut-off wall is driven at upstream face of spillway. There are wing walls at each end and an 8-foot apron extends downstream from control. ICE. Ice forms in the channel above and below, but not on the spillway of the control. ACCURACY. On July 29 high water probably caused a readjustment in the gravel bed of channel disturbed during the construction of the control. Bating curve used July 25 to 29, based on one discharge measurement and shape of subsequent curve. Bating curve used July 30 to October 8 based on nine discharge measurements and is fairly well denned. During this period the intake pipe was obstructed with gravel, and water surface in well was maintained at level of water surface in creek 10 feet upstream from control by seepage through gravel. After October 8, the intake pipe was kept 'open and the stage-discharge relation was permanent; rating curve used October 9 to December 31 based on 7 discharge measurements and is well denned below and poorly denned above 150 second-feet. Operation of water-stage recorder satisfactory; the gage was inspected at least once a week. Daily discharge ascertained by applying to rating table mean daily gage heights determined by inspecting gage-height graph, or, for days of considerable fluctuation by averaging results obtained by applying to rating table mean gage heights for regular intervals of the day. Besults fair. Discharge measurements of Sheep Creek near Thane during the period July 26 to Dec. 81, 1916. Date. July 21 Sept. 2 Oct. G Made by do G. H. Canfield do do do do do Gage height. Feet. Discharge. Sec.-ft. Date. Oct. Dec. 22 Made by G. H. Canfleld do do do Brown and Canfleld. . . . C. 0. Brown do Gage height. Feet. Discharge. Sec.-ft. Daily discharge, in second-feet, of Sheep Creek near Thane for the period July £6 to Dec. 31, 1916. Day. July. Aug. Sept. Oct. Nov. Dec. Day. 2D. July. Aug. Sept. G8 Oct. Nov.

Dec.

MINERAL RESOURCES'- OF ALASKA, 1916. Monthly discharge of-Sheep Creek near Thane for 1916. [Drainage area, 4.57 square miles.] Month. Discharge in second-feet. Maximum. Minimum. Mean. Per square mile. Run-off. Depth in inches on drainage area. Total in acre-feet. 5,160 1,920 18,400 GOLD CREEK AT JUNEAU. LOCATION. At highway bridge at lower end of Last Chance basin, 200 feet upstream from diversion dam of Alaska Electric Light & Power Co., and one-fourth mile from Juneau. DRAINAGE AREA. 9.47 square miles (determined by engineering department of Alaska Gastineau Mining Co., from surveys made by that company). RECORDS AVAILABLE. July 20 to December 31, 1916. GAGE. Stevens water-stage recorder on left bank at upstream side of highway bridge. A staff gage was installed September 19 on left wing wall of diversion dam 200 feet downstream and used in determining the time of changes in stage-discharge relation at the well gage. DISCHARGE MEASUREMENTS. At medium and high stages made from gaging bridge suspended, at right angles to current, from floor of highway bridge; at low stages, made by wading near gage. CHANNEL AND CONTROL. Station is at lower end of a flat gravel basin three-fourths mile long. For 20 feet upstream from gage the stream is confined between the abutments of an old bridge, and for 15 feet downstream it is confined between the abutments of present bridge. For a distance of 130 feet farther downstream the stream is confined in a narrow channel which is not subject to overflow. Because of the steep gradient of channel opposite and for 150 feet below gage, a short stretch of the channel immediately below the gage acts as the control. The operation of the head gates of flume at diversion dam, 200 feet downstream, does not affect the stage-discharge relation at gage, but the swift current during high stages shifts the gravel in bed of stream, thereby causing changes in the stagedischarge relation. ICE. Stage-discharge relation not affected by ice. DIVERSION. Water diverted at several points upstream for power development is returned to creek above gage, except about one-second foot used by the Alaska Juneau Mining Co. The dam 200 feet downstream diverts water into the flume of the Alaska Electric Light & Power Co.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 149 REGULATION. No storage reservoirs above station that regulate the flow. ACCURACY. Stage-discharge relation changed during periods of high water; 20 discharge measurements and 4 simultaneous readings of water-stage recorder and staff gage at diversion dam were made during the period, by use of which rating curves have been constructed applicable as follows: July 24 to August 22, rating curve well defined below and poorly denned above 200 second-feet; August 24 to September 9, well defined below and poorly defined above 200 second-feet; September 11-17, well defined below and poorly defined above 250 second-feet; September 19 to October 11, well defined; October 13-24, well defined between 160 and 260 second-feet, and poorly defined above and below these limits; October 26 to December 31, well defined. The operation of the water-stage recorder was satisfactory throughout the period, as the gage was visited about every other day by an employee of the Alaska Gastineau Mining Co. Daily discharge ascertained by applying to the rating table mean daily gage heights determined by inspecting gage-height graph, or, for days of considerable fluctuation, by averaging the results obtained by applying to rating table mean gage heights for equal intervals of the day. Results fair. Discharge measurements of Gold Creek at Juneau during the period July 20 to Dec. 31, Date. July 20 Aug. 28 Sept. 1 Oct. Nov. 6 Dec. 20 Oct. 15 Made by Perkins and Canfleld. Canfleld and Perkins. do do do G.H. Canfleld... do do do do do do do do do do do C. 0. Brown do Gage height, in feet. Staff gage at dam. Waterstage recorder. Discharge. Sec.-ft. o228 o!80 o250 o227 o Simultaneous readings taken of water-stage recorder and staff gage; discharge ascertained from rating curve for staff gage.

MINERAL RESOURCES OF ALASKA, 1916. Daily discharge, in second-feet, of Gold Creek at Juneau for the period July 20 to Dec. 31, 1916. Day. July. Aug. Sept. Oct. Nov. Dec. Day. IS 20. . . . OC July. IQH Aug. Sept. Oct. Nov. 9Q Dec. O E NOTE. Discharge July 21-24 estimated by comparison with record of flow of Carlson Creek at Sunny Cove. Monthly discharge of Gold Creek at Juneau for the period July 20 to Dec. 31, 1916. [Drainage area, 9.47 square miles.] Mouth. July 20-31 Discharge in second-feet. Maximum. Minimum. 1 Mean. Per square mile. Run-off. Depth in inches on drainage area. Total in acre-feet. 4,830 12,900 13,400 10,900 2,730 45,600 SHERMAN CREEK AT KENSINGTON MINE. LOCATION. At Kensington mine, on east shore of Lynn Canal, one-fourth mile downstream from mouth of Ophir Creek, 1 mile above mouth of creek, and 12 miles north of Berners Bay. Creek at this point flows through a flume 10 feet wide and 20 feet long, constructed for the purpose of affording a better section for making discharge measurements. DRAINAGE AREA. 3.65 square miles (measured on topographic map). RECORDS AVAILABLE. August 17, 1914, to December 31, 1916. GAGE. Vertical staff graduated to tenths and half-tenths, fastened in center of flume, about half the distance along tramway from beach to main camp of mine; read by an employee of Kensington Mining Co. DISCHARGE MEASUREMENTS. Made near lower end of flume in which gage is located. At high stages measuring section is poor because of wave pulsations in flume. CHANNEL AND CONTROL. The natural bed of channel upstream and downstream from gage is very rough. The entire flow at all stages passes through the flume. A free fall at lower end of flume forms a permanent control for gage. Point of zero flow, zero gage height.

WATER-POWER INVESTIGATIONS TN SOUTHEASTERN ALASKA. 151 EXTREMES OF DISCHARGE. 1914-1916: Maximum stage recorded, 2.00 feet October 15, 1915 (discharge determined from an extension of rating curve, 208 secondfeet); minimum stage, 0.20 foot January 25, 27, 29, February 2, 4, 8, and 10, 1916 (discharge, 2.8 second-feet). ICE. Stage-discharge relation not affected by ice. ACCURACY. Stage-discharge relation permanent. Rating curve well defined below 150 second-feet; extended from 150 to 208 second-feet. Gage read to hundredths generally once every other day except October 5, 1914, to February 7, 1915, when it was read only twice a week. Daily discharge for days when gage was read ascertained by applying gage height to rating table. Discharge for other days determined by interpolation or by comparison with records of flow for streams in adjacent drainage basins. Results fair. Discharge measurements of Sherman Creek at Kensington mine during the period Sept. 9 to Dec. 81, 1916. Dale. Sept. 9 Oct. 12 Made by G. H.Canfield J. A. Wilcox. do Gage height. Feet. O.C2 Di.s- oharge. Sec.-ft. Date. Oct. 13 Nov. 9 Made by J.A. Wilcox G. H.Canfield. Gage height. Feet. Discharge. Sec.-ft. Daily discharge, in second-feet, of Sherman Creek at Kensington mine for the period Aug. 17, 1914, to Dec. 31, 1916. Day. 10 11 12 13 14 15 Aug. Sept. IS Oct. Nov. Dec. Day. 16 17 18 19 20 21 22 23 21 25. 26 27 28 29 30 Aug. Sept. Oct. Nov. Dec.

MINERAL .RESOURCES OF ALASKA, 1916. Daily discharge, in second-feet, ofSherman Creek at Kensington mine for the period Aug. 17, 1914, to Dec. 31, 1916 Continued. Day. 1. 2 3 4 S. 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 :. 19 20 21; 22 23 24.. 25 26 27 28 29 30 31 Jan. 2 Q Q Feb. Mar. 90 n Q

Q 9 9 Apr. 4S 3 a 8 Q May. 50, SA June.

July. si Aug. O1 ea CO ISO 40' fid JU Sept. on Oct. an 4Q Nov. OS ft ion ion 1Q ft 10 ft IQ n 11 n 7 O Q n IS ft 1Q ft Dec. ft 5 Q n i z i A. 1 H 7 NOTE. Discharge estimated, because gage was not read, by comparison with records of flow for streams in. adjacent drainage basins, as follows: Oct. 8-11 and Nov. 16-27,1914,20 second-feet; July 1-31, 50 secondfeet; Aug. 1-5, 48 second-feet; Sept. 10-14, 45 second-feet; Oct. 1-8, 29 second-feet; and Dec. 27-31,1916, 5 second-feet.

WATER-POWER INVESTIGATIONS IN SOUTHEASTERN ALASKA. 153 Monthly discharge ofSherman Creek at Kensington mine for the period Aug. 17, 1914, to Dec. 31, 1916. Drainage area, 3.65 square miles.] Month. September. February. March May Juno July The year. February. . 1 .. March... . April May July September. December. Discharge in second-feet. Maximum. Minimum. Mean. S3. 6 Per square mile. Run-off. Depth in inches on drainage area. Total in acre-feet. 1,120 1,790 2,020 1,090 1,760 2,340 2,610 ' 2, 270 1,510 2,760 2,710 20,300 2,980 1,040 3,190 4,970 3,070 3,410 3,730 24,800 3,060 1,590 5,010

MINERAL RESOURCES OF ALASKA, 1916. MISCELLANEOUS MEASUREMENTS. Miscellaneous discharge measurements in southeastern Alaska, 1915-16. Date. July 14 Jan. 11 Feb. Mar. 10 A Stream. Tributary to or discharging into Carroll Inlet... do Stephens Passage do S stephens Passage. Stephens Passage. . . . . Locality. from right near tidewater, three-fourths mile from Coppermount, Prince of Wales Island. on east shore and 1 mile from head of Carroll Inlet, Revillagigedo Island. of creek one-fourth mile east of Sea Level, Revillagigedo Island. Second Lake, Speel River Project (Inc.). of stream from Crater Lake, Speel River project. Tide flats at Speel Point during low tide, one-half mile from cabins of the Speel River project. of stream between Point Salisbury and Point Bishop, north shore Stephens Passage, 11 miles southeast of Juneau. do of creek, 1 mile east of Niblack, Prince of Wales Island. of creek, 500 feet below power house of Chichagof Mining Co., Chichagof Island. upstream from tidewater at cannery, 22 miles southeast of Juneau. Berners Bay, mainland. Gage height. Feet. Discharge. Sec.-ft. ICO CO QQ

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