|Quadrangle map, 1:250,000-scale||VA|
|Quadrangle map, 1:63,360-scale||C-1|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This prospect is located near the crest of the divide between upper Copper Creek and Middle Fork Copper Creek (Van Alstine and Black, 1946, plate 30). It is at an elevation of 5,000 feet in the NE1/4 section 25, T. 2 S., R. 7 E., of the Copper River Meridian. This prospect is approximately located, perhaps to within one-quarter mile. It is locality 71 of Cobb and Matson (1972) and locality 57 of Winkler and others (1981 [OFR 80-892-B]). Cobb (1979 [OFR 79-1241]) includes this prospect under the name Mountain Sheep.|
Geologic descriptionThe Mountain Sheep prospect is in Triassic Nikolai Greenstone about 60 feet below its contact with the overlying Triassic Chitistone Limestone (Van Alstine and Black, 1946, p. 130). Disseminated pyrite, bornite, and a little chalcopyrite occur in shattered greenstone. About 1 percent bornite occurs in fractured zones as much as one inch thick. Limonite, malachite, and some azurite locally stain the greenstone. The copper mineralization is believed to be related to the regional mineralizing event that produced the rich Kennecott copper deposits in the McCarthy quadrangle (MacKevett and others, 1997).
|Geologic map unit||(-144.059395077313, 61.6661340811844)|
|Mineral deposit model||Vein and fracture fillings in greenstone; probably related to Kennecott-type copper deposits (MacKevett and others, 1997)|
|Age of mineralization||The copper mineralization is believed to be related to the mineralizing event that produced the rich Kennecott copper deposits in the McCarthy quadrangle to the east (MacKevett and others, 1997). This event is interpreted to have accompanied Late Jurassic or Early Cretaceous deformation and metamorphism (MacKevett and others 1997, p. 88).|
|Alteration of deposit||Oxidation.|
|Workings or exploration||The prospect was explored before 1923 by small open cuts and a 20-foot adit driven before 1923.|
|Indication of production||None|
Additional commentsThis prospect is within the Wrangell-St. Elias National Park.
Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Valdez quadrangle, Alaska: U.S. Geological Survey Open-File Report 79-1241, 167 p.
Cobb, E.H., and Matson, N.A., Jr., 1972, Metallic mineral resources map of the Valdez quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-438, 1 sheet, scale 1:250,000.
MacKevett, E.M., Jr., Cox, D.P., Potter, R.W., III, and Silberman, M.L., 1997, Kennecott-type deposits in the Wrangell Mountains, Alaska--High-grade copper ores near a basalt-limestone contact, in Goldfarb, R.J., and Miller, L.D., eds., Mineral deposits of Alaska: Economic Geology Monograph 9, p. 66-89.
Van Alstine, R.E., and Black, R.F., 1946, Copper deposits of the Kotsina-Kuskulana district, Alaska: U.S. Geological Survey Bulletin 947-G, p. 121-141.
|Reporters||Travis L. Hudson|
|Last report date||12/14/2001|