|Quadrangle map, 1:250,000-scale||RM|
|Quadrangle map, 1:63,360-scale||D-8|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||Disappointment Creek flows north to Wilson Creek from its headwaters near the summit of Mount Okumiak. The map site is on the lower part of the creek, in the NW1/4 sec. 35, T. 21 N., R. 69 W., of the Seward Meridian. It is included in locality 8 of Hoare and Cobb (1972, 1977).|
Geologic descriptionPlacer gold mining of about the lower one-half mile of Disappointment Creek started in 1914 and continued intermittently until 1939 (Hoare and Cobb, 1977). The pay streak was as much as 300 feet wide. The gravels were 10 to 12 feet thick upstream and more than 35 feet thick at the mouth. The gravels comprised mostly small and well-rounded pebbles and cobbles as much as 8 inches in diameter. The placer concentrates included hematite, magnetite, and minor platinum (Harrington, 1918). Bedrock near the mouth includes slate and conglomerate. Elsewhere in the drainage, Carboniferous (?) to Cretaceous sedimentary and volcanic rocks are intruded by Mesozoic or Tertiary granitic rocks (Hoare and Coonrad, 1959).
|Geologic map unit||(-161.891376732858, 61.8662576298866)|
|Mineral deposit model||Placer Au-PGE (Cox and Singer, 1986; model 39a)|
|Mineral deposit model number||39a|
|Age of mineralization||Quaternary.|
|Workings or exploration||Open-cut mining took place intermittently from 1914 to 1939. A shaft sunk 35 feet failed to reach bedrock near the mouth, but it was abandoned because of flooding.|
|Indication of production||Yes; small|
|MRDS Number||A013408; M045398|
Harrington, G.L., 1918, The Anvik-Andreafski region, Alaska (including the Marshall district): U.S. Geological Survey Bulletin 683, 70 p.
Hoare, J M., and Cobb, E.H., 1972, Metallic mineral resources map of the Russian Mission quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-444, 1 sheet, scale 1:250,000.
Hoare, J.M., and Cobb, E.H., 1977, Mineral occurrences (other than mineral fuels and construction materials) in the Bethel, Goodnews, and Russian Mission quadrangles, Alaska: U.S. Geological Survey Open-File Report 77-156, 98 p.
|Reporters||Travis L. Hudson and Madelyn A. Millholland|
|Last report date||6/10/2001|