Unnamed (north of Bear Valley)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Cu
Ore minerals azurite; malachite

Geographic location

Quadrangle map, 1:250,000-scale NB
Quadrangle map, 1:63,360-scale D-6
Latitude 62.8671
Longitude -143.521
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is on the crest of the range north of Bear Valley. It is in a saddle at an elevation of 5,450 feet, about 6,500 feet southeast of elevation 5870. The site is just inside the west boundary of NE1/4 of section 33, T. 13 N., R. 10 E. of the Copper River Meridian. This is locality 4 of Richter and others (1975). Cobb and Richter (1980) included this deposit as an 'Unnamed occurrence'. It is located to within a few hundred feet.

Geologic setting

Geologic description

Amygdaloidal basalt of the Triassic, Nikolai Greenstone is heavily stained with azurite and malachite at this location. Copper mineralization is locally 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 (-143.523192159316, 62.8667278537196)
Mineral deposit model Basaltic copper (Cox and Singer, 1986; model 23)
Mineral deposit model number 23
Age of mineralization Cretaceous? Alteration and copper mineralization in the Nikolai Greenstone is thought to have accompanied regional deformation and low-grade metamorphism in the Late Jurassic to Early Cretaceous (MacKevett and others, 1997).

Production and reserves

Indication of production None

References

MRDS Number A011380

References

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)
Last report date 11/24/2002