Kontrashibuna Occurrence (Lake), Bristol Bay Mining District, Lake and Peninsula Borough, Alaska, USAi

Regional Level Types
Kontrashibuna Occurrence (Lake)	Occurrence
Bristol Bay Mining District	Mining District
Lake and Peninsula Borough	Borough
Alaska	State
USA	Country

Site is in Lake Clark National Park and Preserve.
Location: Locality is roughly 800 m south of Kontrashibuna Lake, 3.6 km E-SE of Kasna Creek. This is locality 32 of Nelson and others (1985), locality 33 of MacKevett and Holloway (1977), it roughly corresponds to locality 10 of Cobb (1972), and to Area H and approximately Area I of Eakins (1970). Sec. 20, T. 1 N., R. 27 W., of the Seward Meridian. Locality is accurate within 1,000 m.
Geology: The occurrence consists of quartz-pyrite veins containing coarse molybdenite and other sulfide minerals, near the contact of Tertiary mafic volcanic rocks with an intruding Tertiary granitic body. The veins cut the volcanic rocks, but mineralization dies out when veins enter the nearby granite. Also, much iron-staining, gouge, and mylonite along a NE-trending fault. Eakins (1970, Area H) reports that sediment samples in the vicinity yielded values of up to 240 ppm Cu, 50 ppm Mo, 290 ppm Pb, and 980 ppm Zn. Area I of Eakins, 1.2 km NW of this location, produced stream sediment samples with values of up to 240 ppm Cu, 50 ppm Mo, and 440 ppm Pb. Eakins also reports a sample of molybdenite-bearing granite float. A rock sample from the NE-trending fault yielded 8.5 ppm Ag and 2,000 ppm Pb. Resource Associates of Alaska (1976) proposed that the geology may indicate a copper-molybdenum stockwork porphyry.
Workings: Eakins (1970, Area H) reports that sediment samples in the vicinity yielded values of up to 240 ppm Cu, 50 ppm Mo, 290 ppm Pb, and 980 ppm Zn. Area I of Eakins (1970), 1.2 km NW of this location, produced stream sediment samples with values of up to 240 ppm Cu, 50 ppm Mo, and 440 ppm Pb. Eakins also reports a sample of molybdenite-bearing granite float. A rock sample from the NE-trending fault yielded 8.5 ppm Ag and 2,000 ppm Pb.
Age: Tertiary or younger.
Alteration: Unknown
Production: No production
Reserves: No reserves

Commodities (Major) - Mo; (Minor) - Cu, Zn
Development Status: None
Deposit Model: Porphyry Cu-Mo? or Porphyry Mo, Low F ? (Cox and Singer, 1986; models 21a ? or

Other Databases

Link to USGS - Alaska:	LC045

Other Regions, Features and Areas containing this locality

References