Unnamed (southeast Nakchamik Island)

Occurrence in Alaska, United States with commodity Copper

Geologic information

Identification information

Deposit ID 10308351
Record type Site
Current site name Unnamed (southeast Nakchamik Island)

Geographic coordinates

Geographic coordinates: -157.82244, 56.3193 (WGS84)
Relative position This site is located near the southeast coast of Nakchamik Island (MacKevett and Holloway, 1977, locality 1). The island is approximately 10 miles south of Cape Kumliun in Chignik Bay. Site location 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) The alteration is unknown but probably includes propylitic and sericitic types.

Mineral occurrence model information

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

Nearby scientific data

(1) -157.82244, 56.3193

Comments on the geologic information

  • Geologic Description = This site is marked by a color anomaly which coincides with a dacite plug dome that has intruded volcanics of the Oligocene and Eocene Meshik Formation (Detterman and others, 1981; Cox and others, 1981). This mineral occurrence has been described as a porphyry copper deposit consisting of disseminated sulfides in strongly altered intrusive and surrounding volcanic rocks (MacKevett and Holloway, 1977). No mention is made of ore or gangue minerals present.
  • 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

Comments on the workings information

  • Workings / Exploration = Apparently this occurrence has had post-1950 activity (U.S. Bureau of Mines, 1973).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF SW003

Bibliographic references

  • Deposit

    U.S. Bureau of Mines, 1973, Alaska 1:250,000-scale quadrangle map overlays showing mineral deposit locations, principal minerals, and number and type of claims: U.S. Bureau of Mines Open-File Report 20-73, 95 overlays (updated in 1986, 1987).

  • 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

    MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous mineral deposits in the western part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-F, 38 p., 1 sheet, scale 1:1,000,000.

Comments on the references

  • Primary Reference = MacKevett and Holloway, 1977

General comments

Subject category Comment text
Deposit Model Name = Porphyry copper (Cox and Singer, 1986, model 17)
Deposit Other Comments = This site is located 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