Main commodities | Cu |
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Ore minerals | chalcocite; malachite |
Gangue minerals | calcite; quartz |
Quadrangle map, 1:250,000-scale | MC |
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Quadrangle map, 1:63,360-scale | C-4 |
Latitude | 61.6314 |
Longitude | -142.4184 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | This occurrence is on the east valley wall of lower Nizina Glacier (MacKevett, 1970 [GQ 844]). It is at an elevation of about 2,800 feet, 800 feet southeast of hill 3018 in the southeast corner of section 1, T. 3 S., R. 16 E. of the Copper River Meridian. This is locality 114 of MacKevett (1976); the location is accurate to within about 100 feet. |
Geologic descriptionThis prospect consists of chalcocite- and malachite-bearing quartz-calcite veins as much as 8 inches thick that are localized along faults in Triassic Nikolai Greenstone (MacKevett, 1970 [GQ 844]). The veins can be traced for up to 50 feet. They occur near a major fault juxtaposing Nikolai Greenstone against Permian Hasen Creek Formation (MacKevett, 1970 [GQ 844]). 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 | (-142.420496980472, 61.6309847667548) |
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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. |
Indication of production | None |
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Additional commentsThe locality is in the Wrangell-Saint Elias National Park and Preserve. |
MRDS Number | A011728 |
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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.
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Reporters | Travis L. Hudson (Applied Geology, Inc.) |
Last report date | 1/12/2003 |