|Quadrangle map, 1:250,000-scale||BM|
|Quadrangle map, 1:63,360-scale||C-2|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is on the Salmon River at an elevation of about 650 feet. It is in section 5, T. 26 N., R. 5 W., of the Kateel River Meridian. Cobb (1972, MF-386), location 3, and Schmidt and Allegro (1988), location 123.|
The area of this occurrence is underlain by north-trending, lower to mid-Paleozoic sedimentary and metamorphic rocks (Schmidt and Allegro, 1988). Stream float and bedrock consist of graphitic schist, chloritic schist, light-colored quartz-mica schist and abundant quartz. The mineral occurrence consists of chalcopyrite-bearing quartz veins in graphite-chlorite phyllite. The veins are from 3 inches to 3 feet thick and 100 to 250 feet long. Stringers and blebs of pyrite and chalcopyrite, along with some malachite occur in the quartz veins.A sample of quartz stream float contained more than 20,000 ppm Cu, 6 ppm Ag, and 80 ppb Au. Another sample of chalcopyrite-bearing stream float contained 8,200 ppm Cu, 11 ppm Ag, and 5 ppb Au. Twelve stream silt samples were analyzed and no significant metal values were found (Degenhart and others, 1978). Rock samples collected in the mid-1960s contain from 60 ppm to 2 percent Cu, 12 to 94 ppm Pb, 6 to 11 ppm Ag, and 5 to 80 ppb Au (Brosge and others, 1967).
|Geologic map unit||(-159.82288899982, 67.679403618538)|
|Mineral deposit model||Chalcopyrite-bearing quartz veins in a graphite-chlorite phyllite.|
|Age of mineralization||Mid-Paleozoic?|
|Workings or exploration||Some evidence of placer exploration in the area was noted by Degenhart and others (1978). The U.S. Bureau of Mines investigated the area in the mid-1970s (Degenhart and others, 1978). They collected two rock samples and 12 stream silt samples. The area was also mapped and sampled by the U.S. Geological Survey (Brosge and others, 1967).|
|Indication of production||None|
Additional commentsThis occurrence is located in Kobuk Valley National Park.
Cobb, E.H., 1972, Metallic mineral resources map of the Baird Mountains quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-386, 1 sheet, scale 1:250,000.
Cobb, E.H., 1975, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in northern Alaska: U.S. Geological Survey Open-File Report 75-628, 106 p.
|Reporters||Anita Williams (Anchorage, AK)|
|Last report date||12/29/1999|