Unnamed (south of lower Baultoff Creek) (ARDF #NB103) Ag, Cu

Unnamed (south of lower Baultoff Creek)

Occurrence, Inactive

Commodities and mineralogy

Main commodities	Ag; Cu
Other commodities	Cr; Ni; V; Zn
Ore minerals	chalcopyrite
Gangue minerals	calcite; quartz

Geographic location

Quadrangle map, 1:250,000-scale	NB
Quadrangle map, 1:63,360-scale	A-1
Latitude	62.073
Longitude	-141.0725
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This occurrence is on the east nose of the ridge between lower Baultoff Creek and Gravel Creek. It is near elevation 4119 near the southeast corner of SE1/4 of section 31, T. 4 N., R. 24 E. of the Copper River Meridian. This is locality 9 of Richter and others (1973), locality 56 of Richter and others (1975), and National Park Service locality WRST-82 (unpublished data). Cobb and Richter (1980) included this locality as an 'Unnamed occurrence'. It is located to within a few hundred feet.

Geologic setting

Geologic description At this occurrence, quartz veins with calcite and minor chalcopyrite cut a small quartz monzonite stock and its volcanic country rocks (Matson and Richter, 1971 [OFR 71-202]; Richter and others, 1975). A grab sample of a quartz-calcite vein contained 7 parts per million (ppm) silver, 15,000 ppm copper, 700 ppm chromium, 150 ppm nickel, 200 ppm zinc, and 300 ppm vanadium (Matson and Richter, 1971 [OFR 71-202]). The diorite stock intrudes upper Paleozoic volcanic rocks and is inferred to be Cretaceous (Richter and others, 1973).
Geologic map unit	(-141.074630791621, 62.0726794511692)
Mineral deposit model	Quartz-calcite veins with chalcopyrite
Age of mineralization	Cretaceous or Tertiary; the diorite stock that hosts the deposit is inferred to be Cretaceous (Richter and others, 1973).

Production and reserves

Indication of production	None
Additional comments The occurrence is in the Wrangell-St. Elias National Preserve.

References

MRDS Number	A011426
References Cobb, E.H., and Richter, D.H., 1980, Summaries of data on and list of references to metallic and selected nonmetallic mineral deposits in the Nabesna quadrangle, Alaska: U.S. Geological Survey Open-File Report 80-927, 117 p. Matson, N.A., Jr., and Richter, D.H., 1971, Geochemical data from the Nabesna A-1 quadrangle, Alaska: U.S. Geological Survey Open-File Report 71-0202, 10 p. Richter, D.H., Singer, D.A., and Cox, D.P., 1975, Mineral resources map of the Nabesna quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-655-K, 1 sheet, scale 1:250,000.
Reporters	Travis L. Hudson (Applied Geology)
Last report date	11/24/2002