|Quadrangle map, 1:250,000-scale||CR|
|Quadrangle map, 1:63,360-scale||B-3|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is locality 3 of Herreid and Rose (1966). It is about 3.5 miles southeast of the head of Twelvemile Arm, and about 0.3 mile west of the center of section 5, T. 76 S., R. 84 E., of the Copper River Meridian.|
Geologic descriptionThis occurrence is a planar quartz vein about 1 inch thick that contains chalcopyrite (Herreid and Rose, 1966). The vein cuts highly deformed amygdaloidal greenstone marked by ptygmatically-folded quartz-calcite veins. The rocks in the vicinity are greenstone, greenschist, and minor calcareous metagraywacke; they are part of the Wales Group of Late Proterozoic and Cambrian age (Eberlein and others, 1983; Brew, 1996). A few hundred yards to the west, Herbert and Race (1964) found chalcopyrite in limestone; a sample contained 0.3 percent copper.
|Geologic map unit||(-132.683931879102, 55.3077779095561)|
|Mineral deposit model||Chalcopyrite in quartz vein in greenstone.|
|Age of mineralization||Unknown other than that the mineralization is in rocks of Cambrian or older age.|
|Indication of production||None|
Additional commentsThis occurrence is on land that has been conveyed to the Sealaska Corporation, who hold the surface and subsurface rights, or the land is under application for transfer to them.
|MRDS Number||A010017; A010180|
Brew, D.A., 1996, Geologic map of the Craig, Dixon Entrance, and parts of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-2319, 53 p., 1 sheet, scale 1:250,000.
Cobb, E. H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Craig quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-869, 262 p.
Eberlein, G.D., Churkin, Michael, Jr., Carter, Claire, Berg, H.C., and Ovenshine, A. T., 1983, Geology of the Craig quadrangle, Alaska: U.S. Geological Survey Open-File Report 83-91, 52 p.
Herbert, C.F., and Race, W.H., 1964, Geochemical investigations of selected areas in southeastern Alaska, 1964: Alaska Division of Mines and Minerals Geochemical Report 1, 75 p.
|Reporters||D.J. Grybeck (Applied Geology)|
|Last report date||5/1/2004|