|Quadrangle map, 1:250,000-scale||SD|
|Quadrangle map, 1:63,360-scale||A-4|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This prospect is is within a block of 57 mining claims; the site is here located about 1.9 mile east-northeast of Bay Point where Still and others (2002 ) collected their richest samples. It is about 0.3 mile southeast of the northwest corner of section 12, T. 55 S., R. 76 E.|
The property was discovered by Hecla Mining Company in 1990 and they staked 57 claims on it (Jones, 1990; Anderson, 1991). Their work consisted of geologic mapping, and rock, stream-sediment, and soil sampling. They abandoned the claims in 1992.The prospect is a volcanogenic massive-sulfide deposit that consists of disseminations, layers, and pods of pyrite, pyrrhotite, sphalerite, and galena in a stratigraphic unit about 1,000 feet thick that extends for about 1.5 miles (Jones, 1990, Anderson, 1991; Still and others, 2002). The rocks in the area consist of graywacke, mudstone, and andesitic and basaltic rocks of the Gravina Formation of Jurassic or Cretaceous age (Gehrels and Berg, 1992) . The rocks have been metamorphosed to greenschist grade and the most of the sulfides have been remobilized and concentrated in the noses of folds and in layers oblique to the foliation, probably during the metamorphic process. Samples collected by Hecla contained up to 0.2 ounce of gold per ton, 1.4 ounce of silver per ton, 4.1 percent copper, 2.3 percent lead, and 4.68 percent zinc (Anderson, 1991).
|Geologic map unit||(-133.272768681847, 57.1192791187657)|
|Mineral deposit model||Volcanogenic massive sulfide deposit (Cox and Singer, 1986; model 28a).|
|Mineral deposit model number||28a|
|Age of mineralization||The host rocks are of Jurassic or Cretaceous age.|
|Alteration of deposit||Alteration noted but without details. The sulfides were remobilized and concentrated during greenschist-grade metamorphism.|
|Workings or exploration||The property was discovered by Hecla Mining Company in 1990 and they staked 57 claims on it (Jones, 1990; Anderson, 1991). Their work consisted of geologic mapping, and rock, stream sediment, and soil sampling. They abandoned the claims in 1992.|
|Indication of production||None|
Anderson, P.W., 1991, The Bay Point prospect, 1991 progress report; Hecla Mining Company, unpublished report, 16 p. (Copy in the files of the U.S. Bureau of Land Management, Mineral Information Center library, Juneau, Alaska.)
Gehrels, G.E., and Berg, H.C., 1992, Geologic map of southeastern Alaska: U.S. Geological Survey Miscellaneous Investigations Map I-1867, 24 p., 1 sheet, scale 1:600,000.
Jones, B.K., 1990, Geology and mineralization of the Bay Point prospect, southeast Alaska: Hecla Mining Company, unpublished report, 9 p. (Copy in the files of the U.S. Bureau of Land Management minerals library, Juneau, Alaska.)
Still, J.C., Bittenbender, P.E., Bean, K.W., and Gensler, E.G., 2002 Mineral assessment of the Stikine area, central Southeast Alaska: U.S. Bureau of Land Management Technical Report 51, 560 p.
|Reporters||Donald Grybeck (U.S. Geological Survey)|
|Last report date||10/8/2004|