|Quadrangle map, 1:250,000-scale||SM|
|Quadrangle map, 1:63,360-scale||D-7|
|Nearby scientific data||Find additional scientific data near this location|
|Location and accuracy||This prospect is in a saddle of the divide that separates the head of Whitwing Creek to the south from the head of Getmuna Creek on the north. The prospect is at an elevation of about 3,000 feet in the NW1/4 sec. 11, T. 19 N., R. 51 W., of the Seward Meridian. The location is accurate.|
At the Saddle prospect, a syenite-hosted, conjugate set of veins contains axinite, quartz, tourmaline and unspecified, largely oxidized sulfides. The veins range from 1 to 6 inches thick; they dip steeply and strike N60E and N20W. The overall zone trends N20W, parallel to the faulted contact between several phases of the Horn Mountains pluton (Bundtzen and others, 1998). The veins contain 2 to 25 percent tourmaline and axinite, and 1 to 2 percent, fine grained, gray sulfides. The total width of the mineralized zone is estimated to be about 50 feet. Chip samples 3 to 5 feet wide contained up to 514 parts per billion (ppb) gold, 18,900 ppb silver, 642 parts per million (ppm) arsenic, 4.0 ppm cadmium, 48 ppm antimony, 7.0 ppm bismuth, and 14.3 ppm mercury (Bundtzen and others, 1998).The Saddle prospect is in an area of anomalous stream sediment and panned concentrate samples (Gray and others, 1994; Theodorakos and others, 1992). 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||(-158.486887367925, 61.7531249973872)|
|Mineral deposit model||Sn-polymetallic veins or tin veins (Cox and Singer, 1986; models 20b or 15b).|
|Mineral deposit model number||20b or 15b|
|Age of mineralization||Undated; may be related to the nearby Horn Mountain pluton which has been dated at 68-69 Ma (Bundtzen and others, 1998).|
|Alteration of deposit||Axinite-tourmaline-sulfide greisen.|
|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|
Additional commentsIs also known as the 'Whitewing' prospect (Morris Hofseth, oral communication, 1990)
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||5/7/2003|