|Quadrangle map, 1:250,000-scale||MH|
|Quadrangle map, 1:63,360-scale||C-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This placer prospect is located at the forks of upper Ober Creek about 4 miles northeast of Donnelly Station. The workings are at an elevation of 2,500 feet in the NE1/4NE1/4 section 10, T. 14 S., R. 10 E, Fairbanks Meridian. This prospect is described by Moffitt (1942) and corresponds to locality 2 in Cobb (1979 [OFR 79-238]) and locality N1 in table 3 of Nokelberg and others (1991). The location is accurate within a one-half mile.|
Geologic descriptionSmall amounts of gold occur in thin, frozen alluvial stream gravels at this locality (Moffit, 1942). The gravels are derived from extensive glacial deposits and metasedimentary schists (Nokleberg and others, 1991). Placer concentrate collected by Wedow and others (1954) contained as much as 0.011 percent equivalent uranium (eU), as well as monazite, zircon, fluorite, and epidote.
|Geologic map unit||(-145.776190931226, 63.7189978156193)|
|Mineral deposit model||Placer Au (Cox and Singer, 1986; model 39a).|
|Mineral deposit model number||39a|
|Age of mineralization||Holocene.|
|Workings or exploration||In 1942, the site was marked by cabins, pits, and abandoned equipment, suggesting considerable exploration and development (Moffit, 1942). Placer concentrate collected by Wedow and others (1954) averaged about 0.006 percent equivalent uranium (maximum of 0.011 percent).|
|Indication of production||None|
Wedow and others (1954) judged the deposit to be mainly of mineralogic interest because the gold content and radioactivity level were too low to be of economic significance.The prospect is mislocated on plate 7 in U.S. Geological Survey Bulletin 989-D (Moffit, 1954); it is shown as approximately 4 miles farther north than is described in other publications.
Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Mount Hayes quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-238, 140 p.
Moffit, F.H., 1942, Geology of the Gerstle River district, Alaska, with a report on the Black Rapids Glacier: U.S. Geological Survey Bulletin 926-B, p. 107-160.
Moffit, F.H., 1954, Geology of the eastern part of the Alaska Range and adjacent area: U.S. Geological Survey Bulletin 989-D, p. 65-218.
Mulligan, J.J., 1974, Mineral resources of the Trans-Alaska Pipeline corridor: U.S. Bureau of Mines Information Circular 8626, 24 p., 9 sheets, scale 1:250,000.
Nokleberg, W.J., Lange, I.M., Roback, R.C., Yeend, Warren, and Silva, S.R., 1991, Map showing locations of metalliferous lode and placer mineral occurrences, mineral deposits, prospects, and mines, Mount Hayes quadrangle, eastern Alaska Range, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1996-C, 42 p., 1 sheet, scale 1:250,000.
Overstreet, W.C., 1967, The geologic occurrence of monazite: U.S. Geological Survey Professional Paper 530, 327 p.
|Reporters||W.T. Ellis (Alaska Earth Science), C.C. Hawley (Hawley Resource Group), and W.J. Nokleberg (USGS)|
|Last report date||8/9/2002|