Unnamed (east head of Getmuna Creek) (ARDF #SM004) Au, Zn

Unnamed (east head of Getmuna Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities	Au; Zn
Other commodities	Ag; Cd; Sb; W
Ore minerals	unspecified sulfide minerals
Gangue minerals	axinite; quartz

Geographic location

Quadrangle map, 1:250,000-scale	SM
Quadrangle map, 1:63,360-scale	D-7
Latitude	61.7745
Longitude	-158.47919
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This occurrence is located at the toe of an east-west-trending ridge east of the head of Getmuna Creek. It is at an elevation of about 2,600 feet, about 0.5 mile west of hill 3515, in the SW 1/4 sec. 35, T. 20 N., R. 51 W., of the Seward Meridian. The location is accurate.

Geologic setting

Geologic description This occurrence consists of axinite-quartz-sulfide veins in dacite tuff of the Horn Mountains volcanic field (Bundtzen and others, 1998). The veins are 2 to 4 inches thick, strike N25-40W, dip vertically, and can be traced along strike for about 65 feet before disappearing under talus. One grab sample of mineralization contained 54 parts per billion (ppb) gold, 1,300 ppb silver, 1,179 parts per million (ppm) zinc, 3.0 ppm cadmium, and 22 ppm antimony (Bundtzen and others, 1998). The occurrence is in an area marked by anomalous stream sediment and panned concentrate sample sites (Gray and others, 1994; Theodorakos and others, 1992). Stream sediment samples from this area contained up to 26 ppb gold, 950 ppb silver, 290 ppm arsenic, 57 ppm antimony, 4.0 ppm mercury, 6.4 ppm bismuth, and 0.6 ppm tellurium. Panned concentrate samples contained up to 30 ppm gold, 5 ppm silver, 1,500 ppm bismuth, 500 ppm lead, 200 ppm antimony, 1,000 ppm tungsten, 1,000 ppm boron. Panned concentrates also contained up to 1.0 percent scheelite.
Geologic map unit	(-158.481570230434, 61.7737956628415)
Mineral deposit model	Polymetallic vein (Cox and Singer, 1986; model 22c).
Mineral deposit model number	22c
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	Development of axinite-quartz greisen.

Production and reserves

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

References

References 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	5/6/2003