Unnamed (head of Giffin Glacier) (ARDF #MC113) Cu

Unnamed (head of Giffin Glacier)

Occurrence, Inactive

Commodities and mineralogy

Main commodities	Cu
Ore minerals	azurite; chalcocite; malachite; native copper

Geographic location

Quadrangle map, 1:250,000-scale	MC
Quadrangle map, 1:63,360-scale	C-1
Latitude	61.5287
Longitude	-141.3275
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This occurrence is near an arm of the Giffin Glacier. It is at an elevation of about 7,300 feet near the northeast corner of section 13, T. 4 S., R. 22 E. of the Copper River Meridian. This is locality 80 of MacKevett (1976); the location is accurate to within about 1,000 feet.

Geologic setting

Geologic description This occurrence consists of native copper, chalcocite, and alteration minerals (assumed to be malachite and azurite), that form veins and disseminations in a poorly exposed outcrop of Triassic Nikolai Greenstone (MacKevett, 1976). 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	(-141.329544340935, 61.5283349634271)
Mineral deposit model	Basaltic Cu (Cox and Singer, 1986; model 23)
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).
Alteration of deposit	Oxidation.

Production and reserves

Workings or exploration	Limited surface examination.
Indication of production	None
Additional comments The locality is in the Wrangell-Saint Elias National Park and Preserve.

References

References 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