Bertha M.

Prospect in Alaska, United States with commodity Gold

Geologic information

Identification information

Deposit ID 10003605
MRDS ID A106363
Record type Site
Current site name Bertha M.

Geographic coordinates

Geographic coordinates: -154.25267, 60.27943 (WGS84)
Relative position Prospect located on the easternmost distributary of Kijik River, near where the river enters Lake Clark. Locality 22 of Nelson and others (1985) and locality 13 of MacKevett and Holloway (1977). Locality accurate within 1,600 m.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Gold Primary

Materials information

Materials Type of material
Gold Ore

Alteration

  • (Local) Not applicable

Mineral occurrence model information

Model code 119
USGS model code 39a
BC deposit profile C01. C02
Deposit model name Placer Au-PGE
Mark3 model number 54

Nearby scientific data

(1) -154.25267, 60.27943

Comments on the geologic information

  • Geologic Description = Placer claims along Kijik River near Lake Clark. Rock units in the Kijik River drainage include: rhyolitic breccia, ash-flow tuff, flows, and intrusive rocks and subordinate mafic to intermediate flows (Nelson and others, 1983; unit Tv), and Unit TKi10, a granite porphyry with phenocrysts of quartz, plagioclase, and potassic feldspar up to 4 mm across in a groundmass of quartz, potassic feldspar, and plagioclase grains up to 1 mm across. Potassium-argon ages for unit Tv range from 56.2 to 62.7 m.y. indicating a Tertiary age for these rocks (Eakins and others, 1978).
  • Age = Quaternary.

Economic information

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

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 A106363
USGS Alaska Resource Data File ARDF LC038

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

    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

    Nelson, W.H., Carlson, C., and Case, J.E., 1983, Geologic map of the Lake Clark quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-1114-A, 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 = Nelson and others, 1985

General comments

Subject category Comment text
Deposit Model Name = Placer Au (Cox and Singer, 1986; model 39a)
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