|Quadrangle map, 1:250,000-scale||JU|
|Quadrangle map, 1:63,360-scale||D-6|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is at an elevation of about 2,400 feet, approximately 2 miles east of Mt. Case and 1 mile north of the White Glacier. It is in the SW1/4 section 21, T. 35S., R. 57 E. of the Copper River Meridian. This occurrence is close to location J006 of Wells and others (1986). The location is accurate within 1/4 mile.|
The general area is underlain by deformed and metamorphosed Silurian or Devonian carbonate, clastic and volcanic clastic rocks that have been intruded by Upper Jurassic and Lower Cretaceous granitic and dioritic rocks (Brew and others, 1992).Brew and others (1978) map the country rocks at this occurrence as Permian, thin-bedded limestone and argillite, basalt and andesite, and cherty limestone and siltstone. The deposit is in cherty limestone and consists of an iron-stained zone about 8 feet thick that contains pyrite, chalcopyrite, sphalerite, native silver, native gold, ankerite, barite, celestite, strontianite, and witherite. The deposit is truncated to the south by a mafic dike and is lost under surficial material to the north (Brew and others, 1978). Samples of this zone near a volcanic contact contained up to 4.5 percent zinc, 1,900 ppm copper, 7 ppm silver, 5,000 ppm barium and 500 ppm antimony (Still, 1989). Still (1989) interprets the deposit as a stratabound volcanogenic deposit.
|Geologic map unit||(-135.921072796009, 58.8167230947743)|
|Mineral deposit model||Possible metamorphosed Kuroko massive sulfide deposit (Cox and Singer, 1986; model 28a)|
|Mineral deposit model number||28a|
|Alteration of deposit||Conspicuous iron-staining.|
|Indication of production||None|
Brew, D.A., and Ford, A.B., 1985, Preliminary reconnaissance geologic map of the Juneau, Taku River, Atlin, and part of the Skagway 1:250,000 quadrangles, southeastern Alaska: U.S. Geological Survey Open-File Report 85-395, 23 p., 2 sheets, scale 1:250,000.
Brew, D.A., Himmelberg, G.R., Loney, R.A., and Ford, A.B., 1992, Distribution and characteristics of metamorphic belts in the southeastern Alaska part of the North American Cordillera--Metamorphic styles in young and ancient orogenic belts: Journal of Metamorphic Geology, v. 10, no. 3, p. 465-482.
Brew, D.A., Johnson, B.R., Grybeck, D., Griscom, A., Barnes, D.F., Kimball, A.L., Still, J.C., and Rataj, J.L., 1978, Mineral resources of the Glacier Bay National Monument Wilderness Study Area, Alaska: U.S. Geological Survey Open-File Report 78-494, 670 p., 7 sheets.
MacKevett, E.M., Jr., Brew, D.A., Hawley, C.C., Huff, L.C., and Smith, J.G., 1971, Mineral resources of Glacier Bay National Monument, Alaska: U.S. Geological Survey Professional Paper 632, 90 p., 12 plates, scale 1:250,000.
Still, J.C., 1991, Section B: Glacier Bay subarea, in U.S. Bureau of Mines, Mineral investigations in the Juneau Mining District, Alaska, 1984-1988: Volume 2 - Detailed mine, prospect, and mineral occurrence descriptions: U.S. Bureau of Mines Special Publication VOL. 2B, 69 p., 3 sheets.
|Reporters||J.C. Barnett and L.D. Miller (Juneau, Alaska )|
|Last report date||12/15/2001|