|Quadrangle map, 1:250,000-scale||NB|
|Quadrangle map, 1:63,360-scale||A-1|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This prospect is on the ridge south of lower East Fork, Snag Creek. It is at an elevation of about 5,400 feet , 1,500 feet southeast of peak 5664. The prospect is 0.2 mile east of the center of section 23, T. 5 N., R. 21 E. of the Copper River Meridian. This is locality 1 of Richter and others (1973) and locality 47 of Richter and others (1975]). Cobb and Richter (1980) included this prospect under the name 'Sulzer'. It is located to within a few hundred feet.|
Geologic descriptionThis prospect consists of malachite and bornite in fractures and filling amygdules in Triassic, Nikolai Greenstone (Matson and Richter, 1971 [OFR 71-202]; Richter and others, 1975). An adit was driven at least 87 feet along a northwest- trending fracture zone in a flow breccia and an overlying amygdaloidal basalt (Pilgrim, 1931; Moffit, 1943; 1954). 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||(-141.46074100293, 62.196271182737)|
|Mineral deposit model||Basaltic copper (Cox and Singer, 1986; model 23)|
|Mineral deposit model number||23|
|Age of mineralization||Cretaceous? 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).|
|Alteration of deposit||Low-grade metamorphic assemblages including quartz, calcite, epidote, zeolites; some native copper replaces basalt or fills amygdules (Richter and others, 1973).|
|Workings or exploration||This prospect was explored by some open cuts and two adits. One adit was at least 87 feet long (Moffit, 1943).|
|Indication of production||Undetermined|
Additional commentsThe prospect is in the Wrangell-St. Elias National Preserve.
Cobb, E.H., and Richter, D.H., 1980, Summaries of data on and list of references to metallic and selected nonmetallic mineral deposits in the Nabesna quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-927, 117 p.
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.
Matson, N.A., Jr., and Richter, D.H., 1971, Geochemical data from the Nabesna A-1 quadrangle, Alaska: U.S. Geological Survey Open-File Report 71-0202, 10 p.
Moffit, F.H., and Wayland, R.G., 1943, Geology of the Nutzotin Mountains, Alaska, with a section on The igneous rocks: U.S. Geological Survey Bulletin 933-B, p. 103-199.
Moffit, F.H., 1954, Geology of the eastern part of the Alaska Range and adjacent area: U.S. Geological Survey Bulletin 989-D, p. 65-218.
Pilgrim, E.R., 1931, White River precinct, Snag River area, in Stewart, B.D., Report on cooperation between the territory of Alaska and the United States in making mining investigations and in inspection of mines for the biennium ending March 31, 1931: Alaska Terrirorial Department of Mines, p, 74-76.
|Reporters||Travis L. Hudson (Applied Geology)|
|Last report date||11/24/2002|