|Main commodities||Cu; Fe|
|Ore minerals||chalcopyrite; magnetite|
|Quadrangle map, 1:250,000-scale||NB|
|Quadrangle map, 1:63,360-scale||A-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is along the west side of lower Nabesna Glacier. It is at an elevation of about 3,200 feet, about 400 feet west of the glacier. The occurrence is about 0.4 mile south-southwest of the center of section 6, T. 4 N., R. 14 E. of the Copper River Meridian. This is locality 9 of Richter (1973), locality 19 of Richter and others (1975), and National Park Service locality WRST-26 (unpublished data). Cobb and Richter (1980) included this locality as an 'Unnamed occurrence'. It is located to within a few hundred feet.|
Geologic descriptionMassive magnetite containing pyrite and minor chalcopyrite is present in amphibolitized volcanic rock (Richter and others, 1975). The occurrence is near the contact of volcanic rock with a Tertiary porphyry intrusive. The volcanic rock was first thought to be part of an upper Paleozoic volcanic assemblage but Triassic, Nikolai Greenstone is present along most of the porphyry contact (Richter, 1973; 1976).
|Geologic map unit||(-142.923924591991, 62.1515054390868)|
|Mineral deposit model||Contact metasomatic Cu deposit|
|Age of mineralization||Tertiary; the age of the nearby porphyry is inferred to be Tertiary.|
|Alteration of deposit||Amphibolitization of mafic volcanic rock.|
|Indication of production||None|
Additional commentsThe occurrence 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.
|Reporters||Travis L. Hudson (Applied Geology)|
|Last report date||11/24/2002|