Main commodities | Cu |
---|---|
Ore minerals | azurite; malachite; native copper |
Gangue minerals | calcite; epidote; prehnite; zeolite minerals |
Quadrangle map, 1:250,000-scale | MC |
---|---|
Quadrangle map, 1:63,360-scale | D-3 |
Latitude | 61.7634 |
Longitude | -142.0218 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | This prospect is at an elevation of about 6,000 feet, southwest of the terminus of Middle Fork Glacier. It is near the southwest corner of section 20, T. 1 S., R. 19 E. of the Copper River Meridian. This is locality 172 of MacKevett (1976); the location is probably accurate to within 1,000 feet. Cobb and MacKevett (1980) included this prospect under the name 'Copper King (White River)'. |
Geologic descriptionThis deposit at this prospect consists of a 2-meter-thick zone in Triassic amygdaloidal basalt that contains native copper, azurite, and malachite (Capps, 1916; MacKevett, 1976). The copper is intergrown with calcite, prehnite, and other zeolite minerals. Copper mineralization is common in Triassic 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 | (-142.023908742814, 61.7630132173595) |
---|---|
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 | Replacement by calcite, epidote(?), prehnite, and other zeolite minerals. |
Workings or exploration | The prospect was explored by two open cuts and 2 short adits (Capps, 1916). |
---|---|
Indication of production | None |
Additional commentsThe locality is in the Wrangell-Saint Elias National Park and Preserve. |
MRDS Number | A011758 |
---|---|
ReferencesMacKevett, 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 |