Unnamed Prospect (ARDF - NB091; north of Carl Creek), Chisana District, Southeast Fairbanks Borough, Alaska, USA
This page is currently not sponsored. Click here to sponsor this page.
|Latitude & Longitude (WGS84):||62° 3' 7'' North , 141° 35' 38'' West|
|Latitude & Longitude (decimal):||62.0519444444, -141.593888889|
The prospect is in the Wrangell-St. Elias National Preserve.
Location: This prospect is on the side of a ridge that makes up the north wall of Carl Creek. It is at an elevation of about 6,000 feet, about 2,500 feet south of peak 7064. The prospect is about 0.3 mile east-southwest of the center of section 8, T. 3 N., R. 21 E. of the Copper River Meridian. This is locality 4 of Richter and Matson (1970 [OFR 70-275]), locality 45 of Richter and others (1975), and is included in National Park Service locality 92 (unpublished data). Cobb and Richter (1980) included this prospect under the name 'Carl Cr.'. It is located to within a few hundred feet.
Geology: This porphyry copper-molybdenum deposit is similar to the one at NB082, which is located 4,000 feet to the southeast. Pyrite and chalcopyrite occur in quartz veinlets and as disseminations in granodiorite and quartz monzonite of the Cretaceous, Klein Creek pluton (Richter and Matson, 1970 [OFR 70-275]; Richter and others, 1975; Richter and Jones, 1973; Richter, Lanphere, and Matson, 1975). The mineralization is in a 300- by 600-foot hydrothermally altered zone characterized by veins of quartz and sericite. Surface samples average about 0.01 percent copper and less than 0.01 percent molybdenum. A grab sample of limonite-stained granodiorite contained 1.5 parts per million (ppm) silver, 15,000 ppm copper, 15 ppm molybdenum, and 300 ppm zinc (Richter and Matson, 1970 [OFR 70-275]). The deposit is estimated to contain about 8 million tons of material that average 0.20 percent copper and very low amounts of molybdenum (Richter and others, 1975). The Klein Creek pluton has a K/Ar date of 111 +/- 3.6 Ma (Richter, Lanphere, and Matson, 1975). In the area of Carl Creek, the porphyry intrudes volcanic rocks of the Cretaceous, Chisana Formation (Richter and Jones, 1973).
Workings: Surface prospecting has occurred since 1967.
Age: Cretaceous; the Klein Creek pluton has a K/Ar date of 111 +/- 3.6 Ma (Richter, Lanphere, and Matson, 1975).
Alteration: Quartz-sericite-pyrite veining and replacement(?). Oxidation has produced iron- and copper-staining.
Commodities (Major) - Cu; (Minor) - Ag, Au, Mo
Development Status: None
Deposit Model: Porphyry Cu-Mo (Cox and Singer, 1986; model 21a)
5 valid minerals.
This page contains all mineral locality references listed on mindat.org. This does not claim to be a complete list. If you know of more minerals from this site, please register so you can add to our database. This locality information is for reference purposes only. You should never attempt to visit any sites listed in mindat.org without first ensuring that you have the permission of the land and/or mineral rights holders for access and that you are aware of all safety precautions necessary.
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. Richter, D.H., and Jones, D.L., 1973, Reconnaissance geologic map of the Nabesna A-2 quadrangle, Alaska: U.S. Geological Survey Miscellaneous Investigations Series Map I-749, 1 sheet, scale 1:63,360. Richter, D.H., and Matson, N.A., Jr., 1970, Geochemical data from the Nabesna A-2 quadrangle, Alaska: U.S. Geological Survey Open-File Report 70-275, 12 p., 1 sheet, scale 1:63,360. Richter, D.H., Lanphere, M.A., and Matson, N.A., Jr., 1975, Granite plutonism and metamorphism, eeastern Alaska Range, Alaska: Geological Society of American Bulletin, v. 86, p. 819-820. 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.