|Quadrangle map, 1:250,000-scale||MC|
|Quadrangle map, 1:63,360-scale||C-5|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This prospect is on the west valley wall of McCarthy Creek. It is at an elevation of about 5,200 feet, 2,700 feet north-northeast of elevation 6184, and about 200 feet north of the south boundary of section 14, T. 4 S., R. 14 E. of the Copper River Meridian. This is locality 90 of MacKevett (1976); the location is accurate to within about 100 feet. Cobb and MacKevett (1980) included this prospect under the name 'Kennecott (Copper Corp.)'.|
Geologic descriptionThis prospect consists of sheeted calcite veins containing chalcocite that are localized in a shear zone cutting Triassic Nikolai Greenstone (Moffit and Capps, 1911, p. 92; MacKevett, 1976). The shear zone with the calcite veins strikes N 38 E and intersects quartz-epidote veins with some bornite that strike N 78 E. The calcite veins continue upward into Triassic Chitistone Limestone but, the chalcocite is restricted to the part of the veins in the Nikolai Greenstone. The deposits were probably explored by at least pits and open cuts. Copper mineralization is common in Nikolai Greenstone and is thought to have accompanied regional deformation and low-grade metamorphism in the Late Jurassic to Early Cretaceous (MacKevett and others, 1997).
|Geologic map unit||(-142.821680518608, 61.5147645572135)|
|Mineral deposit model||Basaltic Cu (Cox and Singer, 1986; model 23) and/or Kennecott-type copper deposit (after MacKevett and others, 1997)|
|Mineral deposit model number||23?|
|Age of mineralization||Cretaceous? Copper mineralization is common in Nikolai Greenstone and is thought to have accompanied regional deformation and low-grade metamorphism in the Late Jurassic to Early Cretaceous (MacKevett and others, 1997).|
|Workings or exploration||The deposits were probably explored by at least pits and open cuts.|
|Indication of production||None|
Additional commentsThe locality is in the Wrangell-Saint Elias National Park and Preserve.
Cobb, E.H., and MacKevett, E.M., Jr., 1980, Summaries of data on and lists of references to metallic and selected nonmetallic mineral deposits in the McCarthy quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-885, 156 p.
MacKevett, E.M., Jr., 1970, Geologic map of the McCarthy C-4 quadrangle, Alaska: U.S. Geological Survey Geologic Quadrangle Map GQ-844, 8 p., 1 sheet, scale 1:63,360.
MacKevett, E.M., Jr., 1976, Mineral deposits and occurrences in the McCarthy quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-773-B, 2 sheets, 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.
|Reporters||Travis L. Hudson (Applied Geology, Inc.)|
|Last report date||1/12/2003|