Kahiltna River Mine (ARDF - TY027), Yentna District, Matanuska-Susitna Borough, Alaska, USA

See other Kahiltna River occurrences in the Tyonek Quadrangle (ARDF numbers TY028 and TY029) and to the north in the Talkeetna Quadrangle.
Location: Carnes (1976, locality 4) defines this placer prospect as covering approximately a four and one-half mile stretch along the Kahiltna River centered at about the middle of the boundary between Sections 21 and 16 in T. 22., R. 18 W. (Cobb, 1972, MF 385, locality 7 and U.S. Bureau of Mines 1973, localities 22, 39, and 59). This site is on upstream extention of the placer site along the same river described in ARDF TY028.
Geology: Quaternary gravels reconcentrated from Tertiary continental rock, glacial deposits or older bedrock to the north in the Talkeetna quadrangle. Samples are reported to contain up to 0.08% uranium and 0.03% thorium (Cobb,1979, OFR 80-86. p. 17). Probably some small production prior to 1919. Drilling for possible dredging was done in the early 1900's. Limited prospecting may have been done more recently.
Workings: Drilling for possible dredging was done in the early 1900's. Limited prospecting may have been done more recently.
Age: Quaternary

Commodities (Major) - Au; (Minor) - Pt, REE, Sn, Th, Ti, U, W, Zr
Development Status: Yes; small
Deposit Model: Placer gold (Cox and Singer, 1986; model 39a)

References:
Bates, R.G., and Wedow, Helmuth, Jr., 1953, Preliminary summary review of thorium-bearing mineral occurrences in Alaska: U.S. Geological Survey Circular 202, 13 p. Carnes, D.R., 1976, Active Alaskan placer operations, 1975: U.S. Bureau of Mines Open-File Report 98-76, 90 p., 40 plates, scale 1:250,000. Cobb, E.H., 1972, Metallic mineral resources map of the Tyonek quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-385, 1 sheet, scale 1:250,000. Cobb, E.H., 1979, Summary of references to mineral occurrences (other than minerals fuels and construction materials) in the Kenai and Tyonek Quadrangles, Alaska: U.S. Geological Survey Open-File Report 80-86, 36 p. Joesting, H.R., 1942, Strategic mineral occurences in interior Alaska: Alaska Territorial Department of Mines Pamphlet 1, 46 p. MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000. Mertie, J.B., Jr., 1919, Platinum-bearing gold placers of the Kahiltna Valley: U.S. Geological Survey Bulletin 692-D, p. 233-264. Overstreet, W.C., 1967, The geologic occurrence of monazite: U.S. Geological Survey Professional Paper 530, 327 p. Smith, P.S., 1930, Mineral industry of Alaska in 1928: U.S. Geological Survey Bulletin 813-A, p. 1-72. U.S. Bureau of Mines, 1973, Alaska 1:250,000-scale quadrangle map overlays showing mineral deposit locations, principal minerals, and number and type of claims: U.S. Bureau of Mines Open-File Report 20-73, 95 overlays (updated in 1986, 1987).