Unnamed (on Unavikshak Island)

Occurrence in Alaska, United States with commodity Copper

Geologic information

Identification information

Deposit ID 10308355
Record type Site
Current site name Unnamed (on Unavikshak Island)

Geographic coordinates

Geographic coordinates: -157.72245, 56.4893 (WGS84)
Relative position This occurrence is located on Unavikshak Island which is approximately 5 miles east of Cape Kumliun. No specific sites are described, however the location as plotted is accurate to within 1 mile.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore
Quartz Gangue

Alteration

  • (Local) A small zone of sericitic alteration in undescribed rocks lies near the northern part of the island (Wilson, 1980). Propylitic and argillic types may also be present.

Mineral occurrence model information

Model code 53
USGS model code 17
Deposit model name Porphyry Cu
Mark3 model number 4

Nearby scientific data

(1) -157.72245, 56.4893

Comments on the geologic information

  • Geologic Description = The entire island has been mapped as a color anomaly (Cox and others, 1981). A mineralization system on the island has been classified by Wilson (1980) as a volcanic porphyry deposit, although no mention is made of ore or gangue minerals present. Rocks consist of andesite flows and sills of Oligocene to Pliocene age and sedimentary rocks of the Paleocene and Eocene Tolstoi Formation (Detterman and others, 1981). A hornblende andesite sill has been dated at approximately 36 m.y. and sericitic alteration at approximately 30 m.y. (Wilson, 1980).
  • Age = Tertiary.

Economic information

Economic information about the deposit and operations

Development status Occurrence

Comments on exploration

  • Status = Inactive

Mining district

District name Alaska Peninsula

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF SW007

Bibliographic references

  • Deposit

    Cox, D.P., Detra, D.E., and Detterman, R.L., 1981, Mineral resource maps of the Chignik and Sutwik Island quadrangles, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF- 1053-K, 2 map sheets, scale 1:250,000.

  • Deposit

    Detterman, R.L., Miller, T.P., Yount, M.E., and Wilson, F.H.,1981, Geologic map the Chignik and Sutwik Island quadrangles Alaska: U.S. Geologic Survey Miscellaneous Investigations Series Map I- 1229, 1 map sheet, scale 1:250,000.

  • Deposit

    Wilson, F.H., 1980, Late Mesozoic and Cenozoic tectonics and age of porphyry copper prospects, Chignik and Sutwik Island quadrangles, Alaska Peninsula: U.S. Geological Survey Open-File Report 80-543, 94 p., 5 sheets, scales 1:250,000 and 1 inch = 1,000 feet.

Comments on the references

  • Primary Reference = Wilson, 1980

General comments

Subject category Comment text
Deposit Model Name = Porphyry copper (Cox and Singer, 1986, model 17)
Deposit Other Comments = This site is on land selected by the Koniag Native Corporation.

Reporter information

Type Date Name Affiliation Comment
Reporter 31-JAN-00 S.H. Pilcher U.S. Geological Survey