Twin Lakes East

Occurrence in Alaska, United States with commodity Copper

Geologic information

Identification information

Deposit ID 10003609
MRDS ID A106367
Record type Site
Current site name Twin Lakes East

Geographic coordinates

Geographic coordinates: -153.70269, 60.71945 (WGS84)
Relative position Locality is on Peak 6,515 approximately 4.8 km NE of the eastern end of Twin Lakes. This is locality 12 of Nelson and others (1985) and locality 20 of MacKevett and Holloway (1977). Sec. 8, T. 7 N., R. 25 W., of the Seward Meridian. Locality is accurate to within 1.6 km.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary

Materials information

Materials Type of material
Bornite Ore
Chalcopyrite Ore
Pyrrhotite Ore

Alteration

  • (Local) Unknown

Mineral occurrence model information

Model code 184
USGS model code 28a
Deposit model name Massive sulfide, kuroko
Mark3 model number 93
Model code 58
USGS model code 18a
Deposit model name Porphyry Cu, skarn-related
Mark3 model number 9

Host and associated rocks

  • Host or associated Host
    Chronological age 59.45
    Uncertainty 3.25
    Dating method K-Ar
    Stratigraphic age (youngest) Paleocene

Nearby scientific data

(1) -153.70269, 60.71945

Comments on the geologic information

  • Geologic Description = Disseminated chalcopyrite, bornite, and associated pyrrhotite occur in mafic to intermediate metavolcanic rocks interbedded with marble (Nelson and others, 1985; 1983, unit Tvf). Nelson and others (1983) report small intrusive bodies that range in composition from granite to gabbro also occur in vicinity. Potassium-argon ages range from 56.2 to 62.7 m.y. (Eakins and others, 1978). ?
  • Age = The metavolcanic rocks that host the mineralization have potassium-argon ages, by D.L. Turner, that range from 56.2 to 62.7 m.y. (Eakins and others, 1983).
  • Age = Chron age is for metavolcanic rocks that host the mineralization.

Economic information

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Bristol Bay

Comments on the production information

  • Production Notes = No production

Comments on the reserve resource information

  • Reserves = No reserves

Comments on the workings information

  • Workings / Exploration = Unknown

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A106367
USGS Alaska Resource Data File ARDF LC013

Bibliographic references

  • Deposit

    Resource Associates of Alaska, Inc., 1976, Geology and geochemistry of certain land within the Lake Clark National Park: Contract report for U.S. Bureau of Mines, 109 p.

  • Deposit

    Eakins, G.R., Gilbert W.G., and Buntzen, T.K., 1978, Preliminary bedrock geology and mineral resource potential of west-central Lake Clark quadrangle, Alaska: Alaska Division of Geological and Geophysical Surveys Open-File Report 118, 15 p.

  • Deposit

    Cobb, E.H., and Reed, B.L., 1981, Summaries of data on and lists of references to metallic and selected nonmetallic mineral occurrences in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska - Supplement to Open-File Report 76-485: U.S. Geological Survey Open-File Report 81-1343-A, 25 p.

  • Deposit

    Cobb, E.H., and Reed, B.L., 1981, Summaries of data on and lists of references to metallic and selected nonmetallic mineral occurrences in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska - Supplement to Open-File Report 76-485: U.S. Geological Survey Open-File Report 81-1343-B, 20 p.

  • 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 = Nelson and others, 1985

General comments

Subject category Comment text
Deposit Model Name = Kuroko massive sulfide ? or Porphyry Cu, skarn related ? (Cox and Singer, 1986; model 28a ? or 18a?)
Deposit Other Comments = Site is in Lake Clark National Park and Preserve.

Reporter information

Type Date Name Affiliation Comment
Reporter 15-JUN-1998 D.P. Bickerstaff U.S. Geological Survey