|Quadrangle map, 1:250,000-scale||BG|
|Quadrangle map, 1:63,360-scale||D-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is on the north side of the valley of 'Bearhole Creek', which is not named on the D-4 and adjacent D-5 quadrangles (Brabb and Miller, 1962) at an elevation of about 4,500 feet and 1.7 miles west-northwest of peak 6560. It is in the SW 1/4 of section 24, T 10 S, R 16 E of the Copper River Meridian. The location is probably accurate to within a half mile. It is locality 1 of Cobb (1972 [MF 373]; 1979 [OF 79-1246]).|
Geologic descriptionA 20-foot-wide mineralized zone in Mesozoic metasedimentary rocks contains as much as 20 percent pyrite and graphite and traces of chalcopyrite (Brabb and Miller, 1962). The zone contains quartz-feldspar-graphite veins; it is light colored and visible from a distance. Brabb and Miller (1962) observed similar mineralization locally on the south side of Bearhole Creek.
|Geologic map unit||(-142.500307479378, 60.9827556482035)|
|Mineral deposit model||Shear zone with quartz-feldspar-graphite veins?|
|Age of mineralization||Tertiary? The mineralized zone may trend north-south across Bearhole Creek and crosscut the host metasedimentary rocks. High-grade metamorphism in this area is Early Tertiary in age (Hudson and Plafker, 1982).|
|Alteration of deposit||Light color may indicate oxidation.|
|Workings or exploration||Reconnaissance surface observations have been completed at this locality (Brabb and Miller, 1962).|
|Indication of production||None|
Additional commentsThis occurrence is within the Wrangell-St. Elias National Park.
Brabb, E.E., and Miller, D.J., 1962, Reconnaissance traverse across the eastern Chugach Mountains, Alaska: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-341, 1 sheet, scale 1:96,000.
Cobb, E.H., 1972, Metallic mineral resources map of the Bering Glacier quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-373, 1 sheet, scale 1:250,000.
Cobb, E.H., 1979, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Bering Glacier, Icy Bay, Middleton Island, and Yakutat quadrangles, Alaska: U.S. Geological Survey Open-File Report 79-1246, 41 p.
Hudson, T.L., and Plafker, George, 1982, Paleogene metamorphism of an accretionary flysch terrane, eastern Gulf of Alaska: Geological Society of America Bulletin, v. 93, p. 1280-1290.
|Reporters||Travis L. Hudson|
|Last report date||12/12/2001|