Unnamed (in locally-named Sargent Creek) (ARDF #IL039) Au, Cu, Fe

Unnamed (in locally-named Sargent Creek)

Prospect, Inactive

Commodities and mineralogy

Main commodities	Au; Cu; Fe
Other commodities	Ag
Ore minerals	azurite; chalcopyrite; magnetite; malachite
Gangue minerals	calcite; epidote; garnet; quartz

Geographic location

Quadrangle map, 1:250,000-scale	IL
Quadrangle map, 1:63,360-scale	A-5
Latitude	59.1369
Longitude	-154.654
Nearby scientific data	Find additional scientific data near this location
Location and accuracy	This lode prospect is at an elevation of about 1,800 feet in locally-named Sargent Creek (Richter and Herreid, 1965). Sargent Creek was called Crevice Creek by Jasper (1953, 1956). The prospect is near the center of the N1/2 SW1/4 sec. 15, T. 12 S., R. 32 W., Seward Meridian. The prospect coincides with number 7 of Richter and Herreid (1965) and may correspond approximately wth locality 19 of Detterman and Cobb (1972). The location is accurate within 500 feet.

Geologic setting

Geologic description The country rocks at this prospect are chiefly intermediate and basic volcanic rocks of the Jurassic Talkeetna Formation (Richter and Herreid, 1965; Detterman and Reed, 1980). The deposit was largely snow covered when visited by Richter and Herreid, but they described dump samples of epidote-garnet tactite (skarn), garnet-magnetite skarn, massive magnetite, and massive magnetite-calcite rock. The samples were copper-stained, presumably by malachite and azurite, and contained chalcopyrite.
Geologic map unit	(-154.656115786815, 59.1362096241572)
Mineral deposit model	Fe skarn, Cu skarn (Cox and Singer, 1986; models 18d, 18b).
Mineral deposit model number	18d, 18b
Age of mineralization	Probably Jurassic, the age of the nearby Pilot Knob granodiorite (IL041) (Richter and Herreid, 1965).
Alteration of deposit	Contact metasomatism. Oxidation of copper.

Production and reserves

Workings or exploration	Test pits were largely snow covered when visited by Richter and Herreid (1965); the claim-owner (Sargent) reported good showings of disseminated chalcopyrite. The deposit was probably covered by the McNeil (IL043) claims.
Indication of production	None

References

MRDS Number	A013049
References Detterman, R.L., and Cobb, E.H., 1972, Metallic mineral resources map of the Iliamna quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-364, 1 sheet, scale 1:250,000. Detterman, R.L., and Reed, B.L., 1980, Stratigraphy, structure, and economic geology of the Iliamna quadrangle, Alaska: U.S. Geological Survey Bulletin 1368-B, 86 p. Jasper, M.W., 1953, Preliminary report on copper occurrences on McNeil claim group, Paint River area, Kamishak Bay region: Alaska Territorial Department of Mines Property Examination 103-1, 14 p., 6 sheets. Jasper, M.W., 1956, McNeil copper claim group, Paint River area: Alaska Territorial Department of Mines Property Examination 103-2, 19 p., 3 sheets. Richter, D.H., and Herreid, G.H., 1965, Geology of the Paint River area, Iliamna Quadrangle, Alaska: Alaska Division of Mines and Minerals Geologic Report 8, 18 p., 1 sheet, scale 1:31,680.
Reporters	C.C. Hawley, Hawley Resource Group, Anchorage, Alaska
Last report date	6/10/2003