|Quadrangle map, 1:250,000-scale||CV|
|Quadrangle map, 1:63,360-scale||C-6|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This site represents two prospects in a 2.5-mile-long linear area along the bluff above the northwest shore of Sheep Bay. The map site is at the approximate midpoint between the prospects, in the NW1/4 sec. 11, T. 14 S., R. 5 W., of the Copper River Meridian. This site includes both sites C-52 and C-53 of Jansons and others (1984).|
Geologic descriptionThe prospect consists of chalcopyrite-bearing quartz veins in the Tertiary Orca Group turbidites along the contact of the Sheep Bay pluton (Jansons and others, 1984; Nelson and others, 1985). The Sheep Bay pluton has been radiometrically dated at about 51 Ma (Winkler and Plafker, 1981). Three analyzed samples from Jansons and others' (1984) location C-52 contained 26-115 ppm Cu. Eleven additional samples from the contact area contained 13 ppm to 0.14% Cu and <0.1 ppm to 8.5 ppm silver.
|Geologic map unit||(-146.031990210604, 60.6694598456944)|
|Mineral deposit model||Copper skarn?|
|Age of mineralization||The age of mineralization is probably 51 Ma based on the age of the Sheep Bay pluton.|
|Alteration of deposit||Contact metamorphism.|
|Workings or exploration||Area examined by the U.S. Bureau of Mines as part of a mineral evaluation of the Chugach National Forest. Three analyzed samples from location C-52 contained 26-115 ppm Cu. Eleven additional samples from the contact area contained 13 ppm to 0.14% Cu and <0.1 ppm to 8.5 ppm silver (Jansons and others, 1984).|
|Indication of production||None|
Additional commentsChugach Alaska Corporation, Anchorage, Alaska has control of these lands.
Jansons, Uldis, Hoekzema, R.B., Kurtak, J.M., and Fechner, S.A., 1984, Mineral occurrences in the Chugach National Forest, southcentral Alaska: U.S. Bureau of Mines Mineral Land Assessment 5-84, 218 p., 2 sheets, scale 1:250,000.
Nelson, S.W., Dumoulin, J. A., and Miller, M.L., 1985, Geologic map of the Chugach National Forest, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1645-B, 16 p., 1 sheet, scale 1:250,000.
|Reporters||S.W. Nelson, Anchorage, AK|
|Last report date||6/10/2000|