Unnamed Prospect (ARDF - NB091; north of Carl Creek), Chisana Mining District, Southeast Fairbanks Census Area, Alaska, USAi

Regional Level Types
Unnamed Prospect (ARDF - NB091; north of Carl Creek)	- not defined -
Chisana Mining District	Mining District
Southeast Fairbanks Census Area	Census Area
Alaska	State
USA	Country

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(1970 [OFR 70-275]), locality 45 of Richter and others (1975), and is included in National Park Service locality 92 (unpublished data).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)

Other Databases

Link to USGS - Alaska:	NB091

Other Regions, Features and Areas containing this locality

References