|Quadrangle map, 1:250,000-scale||OP|
|Quadrangle map, 1:63,360-scale||A-2|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Bedrock Gulch, about 7.5 miles south-southeast of Ophir, is a short, north tributary to Dollar Creek, which is an east tributary to Beaver Creek. Bedrock Gulch is not named on U.S. Geological Survey topographic maps; most of it is in sec. 20, T. 28 S., R. 12 E., Kateel River Meridian. This site is location 10 of Cobb (1972 [MF 367]). The location is accurate within 1/2 mile.|
Geologic descriptionThe area of Bedrock Gulch is underlain by undivided clastic rocks (Chapman and others, 1987). The thickness of pay gravel in the 1950s was 3-4 feet, and it was covered by 7 to 8 feet of muck and overburden. Saunders (1960) noted that Mr. Lindquist, the operator, expected to finish placer mining that area in 1959 and then move 3 or 4 miles downstream and continue mining. Smith (1937) reports active non-dredge mining along Bedrock Gulch in 1935. The next report of mining is in 1959 (Saunders, 1960).
|Geologic map unit||(-156.620363976196, 63.0446675433136)|
|Mineral deposit model||Placer Au (Cox and Singer, 1986; model 39a)|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary.|
|Workings or exploration||Smith (1937) reports non-dredge mining along Bedrock Gulch in 1935. The next mention of mining is in 1959, when Saunders (1960) reports that Hjalmar Lindquist was mining the upper portion of the gulch with a TD-14 tractor. Mr. Lindquist expected to finish mining that area in 1959 and then move 3 or 4 miles downstream and continue mining.|
|Indication of production||Yes; small|
Bundtzen, T.K., and Miller, M.L., 1997, Precious metals associated with Late Cretaceous-early Tertiary igneous rocks of southwestern Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska: Economic Geology Monograph 9, p. 242-286.
Chapman, R.M., Patton, W.W., and Moll, E.J., 1985, Reconnaissance geologic map of the Ophir quadrangle, Alaska: U.S. Geological Survey Open-File Report 85-203, 19 p., 1 sheet, scale 1:250,000.
Cobb, E.H., 1972, Metallic mineral resources map of the Ophir quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-367, 1 sheet, scale 1:250,000.
Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction material) in the Iditarod and Ophir quadrangles, Alaska: U.S. Geological Survey Open-File Report 76-576, 101 p.
Saunders, R.H., 1960, Itinerary report on a trip to the Flat and Ophir Districts: Alaska Territorial Department of Mines Itinerary Report 64-2, 15 p.
|Last report date||8/7/2001|