Unnamed (on Bear Creek) (ARDF #CA027) Au, Cu, Pb, Zn

Unnamed (on Bear Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities	Au; Cu; Pb; Zn
Ore minerals	bournonite; galena; gold; pyrite; sphalerite
Gangue minerals	calcite; limonite; quartz

Geographic location

Quadrangle map, 1:250,000-scale	CA
Quadrangle map, 1:63,360-scale	C-5
Latitude	65.54
Longitude	-161.06
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This occurrence is on Bear Creek, about a half-mile above the junction of Bob Creek. The map site is 200 feet north of the north end of the airstrip, in section 25, T. 2 N., R. 12 W., of the Kateel River Meridian. Cobb (1972, MF-389), location 15.

Geologic setting

Geologic description Miller and Elliott (1969) report that galena, sphalerite and pyrite occur in andesite at the north end of the airstrip on Bear Creek. The sulfides occur in quartz-calcite veinlets and as disseminated grains in the andesite near a mafic syenite dike. The mineralized zone is about 200 feet wide and trends northwest. Gold can be panned from the limonite cap over the mineralized rock. Stream-sediment samples downstream from the mineralized zone indicate a lead-zinc-copper anomaly extending for about a mile. Soil samples from a drainage ditch above the deposit contain anomalous lead and zinc. Placer gold has been intermittently mined on Bear Creek, mostly downstream from the mineralized area. A polished section shows that arsenopyrite, bournonite and a little gold are present in the sulfide aggregate. This occurrence occurs entirely in Jurassic-Cretaceous andesite and has anomalously high values of antimony and gold. Seven rock samples were collected and analyzed by Miller and Elliot (1969). Gold values were all anomalous and varied from 0.4 to 3.0 ppm; silver varied from 1.5 to 150 ppm; arsenic varied from 500 to greater than 10,000 ppm; copper ranged from 50 to 1,000 ppm; lead ranged from 200 to greater than 20,000 ppm; and zinc varied from 700 to greater than 10,000 ppm.
Geologic map unit	(-161.062655745548, 65.5393313203667)
Mineral deposit model	Sulfides in altered andesite.
Age of mineralization	Jurassic - Cretaceous or younger.
Alteration of deposit	Limonite alteration.

Production and reserves

Workings or exploration	The site has been visited and sampled by U.S. Geological Survey and ADGGS geologists. Several exploration companies have also visited the occurrence.
Indication of production	None
Additional comments Not well enough exposed to evaluate potential of deposit.

References

MRDS Number	A013493
References Anderson, Eskil, 1947, Mineral occurrences other than gold deposits in northwestern Alaska: Alaska Territorial Division of Mines Pamphlet 5-R, 48 p. Berg, H.C., and Cobb, E.H., 1967, Metalliferous lode deposits of Alaska: U.S. Geological Survey Bulletin 1246, 254 p. Brooks, A.H., 1918, Mineral resources of Alaska, 1916: U.S. Geological Survey Bulletin 662, 469 p. Brooks, A.H., 1921, The future of Alaska mining, in Martin, G.C., and others, Mineral resources of Alaska, 1917: U.S. Geological Survey Bulletin 714-A, p. 5-57. Brooks, A.H., 1923, The Alaska mining industry in 1921: U.S. Geological Survey Bulletin 739-A, p. 1-50. Brooks, A.H., and Martin, G. C., 1921, The Alaska mining industry in 1919: U.S. Geological Survey Bulletin 714-A, p. 59-95. Bundtzen, T.K., Green, C.B., Deagen, J.R., and Daniels, C.L., 1987, Alaska's mineral industry, 1986: Alaska Division of Geological and Geophysical Surveys Special Report 40, 68 p. Cass, J.T., 1959, Reconnaissance geologic map of the Candle quadrangle, Alaska: U.S. Geological Survey Miscellaneous Investigations Series Map I-287, 1 sheet, scale 1:250,000. Cathcart, S.H., 1920, Mining in northwestern Alaska: U.S. Geological Survey Bulletin 712-G, p. 185-198. Cobb, E.H., 1972, Metallic mineral resources map of the Candle Quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-389, 1 sheet, scale 1:250,000. Cobb, E.H., 1973, Placer deposits of Alaska: U.S. Geological Survey Bulletin 1374, 213 p. Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Candle, Holy Cross, Norton Bay, Nulato, and Unalakleet quadrangles, Alaska: U.S. Geological Survey Open-File Report 76-866, 102 p. Eakin, H.M., 1915, Placer mining in Seward Peninsula: U.S. Geological Survey Bulletin 622-I, p. 366-373. Gault, H.R., Killeen, P.L., West, W.S., and others, 1953, Reconnaissance for radioactive deposits in the northeastern part of the Seward Peninsula, Alaska, 1945-47 and 1951: U.S. Geological Survey Circular 250, 31 p. Harrington, G.L., 1919, The gold and platinum placers of the Kiwalik-Koyuk region: U.S. Geological Survey Bulletin 692-G, p. 369-400. Harrington, G.L., 1921, Mining on Seward Peninsula: U.S. Geological Survey Bulletin 714-F, p. 229-237. Henshaw, F.F., 1909, Mining in the Fairhaven precinct: U.S. Geological Survey Bulletin 379-F, p. 355-369. Herreid, G.H., 1965, Geology of the Bear Creek area, Seward Peninsula, Candle quadrangle, Alaska: Alaska Division of Geological and Geophysical Surveys Geological Report 12, 16 p., 1 sheet, scale 1:40,000. Martin, G.C., 1919, Alaska Mining Industry in 1917: U.S. Geological Survey Bulletin 692-A, p. 11-42. Martin, G.C., 1920, The Alaska mining industry in 1918: U.S. Geological Survey Bulletin 712-A, p. 1-52. Mertie, J.B., Jr., 1918, Placer mining on Seward Peninsula in Brooks, A.H., and others, Mineral resources of Alaska, report on progress of investigations in 1916: U.S. Geological Survey Bulletin 662, p. 451-458. Mertie, J.B., Jr., 1923, The occurrence of metalliferous deposits in the Yukon and Kuskokwim regions: U.S. Geological Survey Bulletin 739-D, p. 149-165. Miller, T.P., and Elliott, R.L., 1969, Metalliferous deposits near Granite Mountain, eastern Seward Peninsula, Alaska: U.S. Geological Survey Circular 614, 19 p. Moffit, F.H., 1904, The Kotzebue placer gold field of Seward Peninsula in Emmons S.F., and Hayes, C.W., Contributions to economic geology, 1903, U.S. Geological Survey Bulletin 225, p. 74-80. Moffit, F.H., 1905, The Fairhaven gold placers, Seward Peninsula, Alaska: U.S. Geological Survey Bulletin 247, 85 p. Purington, C.W., 1905, Methods and costs of gravel and placer mining in Alaska: U.S. Geological Survey Bulletin 263, 273 p. 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Smith, P.S., 1934, Mineral Industry of Alaska in 1933: U.S. Geological Survey Bulletin 864-A, p. 1-94. Smith, P.S., 1936, Mineral Industry of Alaska in 1934: U.S. Geological Survey Bulletin 868 A, p. 1-91. Smith, P.S., 1937, Mineral Industry of Alaska in 1935: U.S. Geological Survey Bulletin 880 A, p. 1-95. Smith, P.S., 1938, Mineral Industry of Alaska in 1936: U.S. Geological Survey Bulletin 897 A, p. 1-107. Smith, P.S., 1939, Mineral Industry of Alaska in 1937: U.S. Geological Survey Bulletin 910 A, p. 1-113. Smith, P.S., 1939, Mineral industry of Alaska in 1938: U.S. Geological Survey Bulletin 917-A, p. 1-113. Smith, P.S., 1941, Mineral Industry of Alaska in 1939: U.S. Geological Survey Bulletin 926 A, p. 1-106. Smith, P.S., 1942, Mineral industry of Alaska in 1940: U.S. Geological Survey Bulletin 933-A, p. 1-102. Smith, P.S., and Eakin, H.M., 1910, Mineral resources of the Nulato-Council region: U.S. Geological Survey Bulletin 442-H, p. 316-352. Smith, P.S., and Eakin, H.M., 1911, A geologic reconnaissance in southeastern Seward Peninsula, and the Norton Bay-Nulato region, Alaska: U.S. Geological Survey Bulletin 449, 146 p. Smith, S.S., 1917, The mining industry in the Territory of Alaska during the calendar year 1915: U.S. Bureau of Mines Bulletin 142, 65 p.
Reporters	Anita Williams (Anchorage, AK)
Last report date	1/12/2000