|Quadrangle map, 1:250,000-scale||CR|
|Quadrangle map, 1:63,360-scale||A-2|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||The HET and CPY occurrences are about 0.6 mile northeast of the head of Hetta Lake at about 1,400 to 1,500 feet in elevation. They are about 0.6 mile west-northwest of the center of section 18, T. 77 S, R. 86 E.|
Geologic descriptionThe HET and CPY occurrences are near a thrust contact between outcrops of hornfels (Herreid and others, 1978; Maas and others, 1991, 1995). A Cretaceous granodiorite intrusion crops out just to the south on the north side of Hetta Lake. The occurrences consist of chalcopyrite-bearing float. The highest copper value in 6 samples was 1,251 parts per million copper; gold was not detected.
|Geologic map unit||(-132.523057354717, 55.1936154691833)|
|Mineral deposit model||Copper skarn? (Cox and Singer, 1986; model 18b).|
|Mineral deposit model number||18b?|
|Age of mineralization||Probably Cretaceous.|
|Alteration of deposit||Development of hornfels.|
|Workings or exploration||Only surface sampling by government geologists.|
|Indication of production||None|
Additional commentsThese occurrences are on land whose surface and subsurface rights have been conveyed to, or are under application for transfer to, the Sealaska Corporation.
Glavinovich, P.S., 1987, Sealaska Corporation Minerals Breifing Book, December 1987: Sealaska Corporation, 40 p. and plates. (Unpublished report held by Sealaska Corporation, Juneau, Alaska).
Hedderly-Smith, D.A., 1997, Results of 1996 reconnaissance sampling at Hetta Lake-Sealaska minerals reconnaissance project: Sealaska Corporation, 17 p.with addendum. (Unpublished report held by the Sealaska Corporation, Juneau, Alaska.)
Hedderly-Smith, D.A., 1999, Inventory of metallic mineral prospects, showings and anomalies on Sealaska lands, 1988 through 1998: Sealaska Corporation, Juneau, Alaska, 217 p. (internal report held by Sealaska Corporation, Juneau, Alaska).
Herreid, Gordon, Bundtzen, T.K., and Turner, D.L., 1978, Geology and geochemistry of the Craig A-2 quadrangle, Prince of Wales Island, southeastern Alaska: Alaska Division of Geological and Geophysical Surveys Geologic Report 48, 49 p.
Maas, K.M., Bittenbender, P E., and Still, J.C., 1995, Mineral investigations in the Ketchikan mining district, southeastern Alaska: U.S. Bureau of Mines Open-File Report 11-95, 606 p.
|Reporters||D.J. Grybeck (Applied Geology)|
|Last report date||5/1/2004|