Unnamed (south bank of Kotsina River)

Prospect in Alaska, United States with commodity Copper

Geologic information

Identification information

Deposit ID 10001074
MRDS ID A011756
Record type Site
Current site name Unnamed (south bank of Kotsina River)
Alternate or previous names Unnamed

Geographic coordinates

Geographic coordinates: -143.87142, 61.71772 (WGS84)
Relative position South side of Kotsina River, 2,500 ft downstream from confluence of Amy Creek with Kotsina River. Best location: MacKevett and others, 1978, loc. 6. Accurate within radius of 100 feet.
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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 Gangue

Host and associated rocks

  • Host or associated Associated
    Rock type Metamorphic Rock > Metavolcanic Rock > Mafic Metamorphic Rock > Greenstone
    Rock unit name Nikolai Greenstone
    Rock description Nikolai Greenstone
    Stratigraphic age (youngest) Late Triassic
    Stratigraphic age (youngest) Late Triassic
  • Host or associated Host
    Rock type Plutonic Rock > Mafic Intrusive Rock > Gabbro
    Rock unit name Nikolai Greenstone;
    Rock description Nikolai Greenstone;

Nearby scientific data

(1) -143.87142, 61.71772

Comments on the geologic information

  • Geologic Description = Several pyrite and chalcopyrite-bearing veins less than 30 cm thick in gabbro and felsic dikes. Gabbro is interpreted as feeder dikes for the Triassic Nikolai Greenstone.

Economic information

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Chistochina

Comments on the workings information

  • Workings / Exploration = Type of workings: underground. Explored by several short adits. Selected samples (MacKevett, 1976) assayed as much as: 3 ppm Ag, 1,000 ppm Cu, 20 ppm Mo.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A011756
USGS Alaska Resource Data File ARDF MC026

Bibliographic references

  • Deposit

    Moffit, F.H., and Maddren, A.G., 1909, Mineral resources of the Kotsina-Chitina region, Alaska: U.S. Geological Survey Bulletin 374, 103 p.

  • Deposit

    Moffit, F.H., and Mertie, J.B., Jr., 1923, The Kotsina-Kuskulana district, Alaska: U.S. Geological Survey Bulletin 745, 149 p.

  • Deposit

    MacKevett, E.M., Jr., 1976, Mineral deposits and occurrences in the McCarthy quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-773-B, scale 1:250,000.

  • Deposit

    MacKevett, E.M., Jr., Smith, J.G., Jones, D.L., and Winkler, G.R., 1978, Geologic map of the McCarthy C-8 quadrangle, Alaska: U.S. Geological Survey Geologic Quadrangle Map GQ-1418, scale 1:63,360.

  • Deposit

    MacKevett, E.M., Jr., Smith, J.G., Jones, D.L., and Winkler, G.R., 1978, Geologic map of the McCarthy C-8 quadrangle, Alaska: U.S. Geological Survey Geologic Quadrangle Map GQ-1418, 1 sheet, scale 1:63,360.

Comments on the references

  • Primary Reference = Moffit and Mertie, 1923

General comments

Subject category Comment text
Deposit Model Name = Lode: vein
Deposit Other Comments = See also: unnamed occurrence no. 171 in MacKevett (1976).

Reporter information

Type Date Name Affiliation Comment
Reporter 22-SEP-1997 Leonard, K.R. U.S. Geological Survey
Reporter 22-SEP-1997 Elliott, R.L. U.S. Geological Survey
Reporter 22-SEP-1997 Richter, D.H. U.S. Geological Survey