|Quadrangle map, 1:250,000-scale||SM|
|Quadrangle map, 1:63,360-scale||C-7|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This occurrence is at an elevation of about 2,100 feet on a steep, southwest-facing knob east of junction of the two headwater tributaries in the cirque at the head of the Whitewing Valley. The occurrence is about 0.3 mile southeast of the center of section 14, T. 19 N., R. 51 W., of the Seward Meridian and 0.8 mile southeast of peak 3310. The location is accurate.|
This occurrence consists of a sulfide-bearing quartz greisen in and adjacent to a felsic dike that intrudes syenite of the Cretaceous Horn Mountains pluton. Fine-grained disseminated sulfides occur both in the dike and in a quartz greisen breccia zone in the syenite; the greisen also contains barite and tourmaline. The sulfides are oxidized to goethite. One grab sample taken from the mineralized zone contained 113 parts per billion (ppb) gold, 1,400 ppb silver, 171 parts per million (ppm) copper, 171 ppm arsenic, 82 ppm antimony, 2,300 ppm barium, and 2.0 ppm bismuth (Bundtzen and others, 1998).The occurrence is in an area of anomalous stream sediment and panned concentrate samples (Gray and others, 1994; Theodorakos and others, 1992). The stream sediment samples contained up to 700 ppb gold, 680 ppb silver, 120 ppm copper, 370 ppm arsenic, 35 ppm antimony, and other elevated metal values. Panned concentrates contained up to 30.0 ppm gold, 15.0 ppm silver, 2,000 ppm lead, 300 ppm antimony, 1,000 ppm bismuth, and 700 ppm tungsten; several samples contained microscopically visible gold, scheelite, and barite.
|Geologic map unit||(-158.470457235782, 61.73295472651)|
|Mineral deposit model||Silver-polymetallic veins or tin veins (Cox and Singer, 1986; models 20b or 15b).|
|Mineral deposit model number||20b or 15b|
|Age of mineralization||May be related to the Horn Mountain pluton which has been dated at 68-69 Ma (Bundtzen and others, 1998).|
|Alteration of deposit||Development of quartz-tourmaline greisen; oxidation of sulfides.|
|Workings or exploration||Surface sampling was conducted by the Alaska Division of Geological and Geophysical Surveys in 1990 (Bundtzen and others, 1998).|
|Indication of production||None|
Bundtzen, T.K., Harris, E.E., Miller, M.L., Layer, P.W., and Laird, G.M., 1998, Geology of the Sleetmute C-7, C-8, D-7, and D-8 quadrangles, Horn Mountains, southwestern Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 98-12, 38 p., one sheet, scale 1:63,360.
Cady, W.M., Wallace, R.E., Hoare, J.M., and Webber, E.J., 1955, The central Kuskokwim region, Alaska: U.S. Geological Survey Professional Paper 268, 132 p.
Gray J.E., Theodorakos, P.M., Bradley, L.A., and Bullock, J.H., 1994, Favorable areas for metallic mineral resources in and near the Horn Mountains, Sleetmute quadrangle, southwestern Alaska: U.S. Geological Survey Bulletin 2068, p. 79-90.
Theodorakos, P.M., Borden, J.C., Bullock, J.H. Jr., Gray, J.E., and Hageman, P.L., 1992, Analytical data and sample locality map of stream sediment and heavy mineral concentrate samples collected from the Horn Mountains area, Sleetmute quadrangle, southwest Alaska: U.S. Geological Survey Open-File Report 92-708-A, 36 p., one sheet, scale 1:250,000.
|Reporters||T.K. Bundtzen (Pacific Rim Geological Consulting, Inc.) and M.L. Miller (U.S. Geological Survey)|
|Last report date||5/8/2003|