Unnamed (inner Tamgas Harbor)

Occurrence in Alaska, United States with commodity Copper

Geologic information

Identification information

Deposit ID 10001628
MRDS ID A012392
Record type Site
Current site name Unnamed (inner Tamgas Harbor)

Geographic coordinates

Geographic coordinates: -131.5437, 55.07863 (WGS84)
Relative position This occurrence is at the south tip of an islet just off the east shoreline of inner Tamgas Harbor, about 0.85 mile north-northeast of Crab Point. The site is in section 27, T. 78 S., R. 92 E., of the Copper River Meridian. It corresponds to loc. 42 in Berg (1972 [I 684]), loc. 150 in Elliott and others (1978), and loc. 46 in Karl (1992). The location is accurate within a few hundred feet.
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Geographic areas

Country State
United States Alaska


Commodity Importance
Copper Primary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore

Host and associated rocks

  • Host or associated Host
    Rock type Metamorphic Rock > Schist

Nearby scientific data

(1) -131.5437, 55.07863

Comments on the geologic information

  • Geologic Description = The country rocks at this site are greenschist-grade schist and hornfels, probably derived from volcanic, sedimentary, and intrusive rocks of Silurian and Ordovician age (Berg, 1972; Berg and others, 1988). The occurrence consists of pyrite and chalcopyrite very sparsely disseminated in the schist and hornfels (Berg, 1992, loc. 42).

Economic information

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic

Mining district

District name Ketchikan

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A012392
USGS Alaska Resource Data File ARDF KC154

Bibliographic references

  • Deposit

    Berg, H.C., 1972, Geologic map of Annette Island, Alaska: U.S. Geological Survey Miscellaneous Geologic Investigations Map I-684, 8 p., 1 sheet, scale 1:63,360,

  • Deposit

    Elliott, R.L., Berg, H.C., and Karl, Susan, 1978, map and table describing metalliferous and selected nonmetalliferous mineral deposits, Ketchikan and Prince Rupert quadrangles, Alaska: U.S. Geological Survey Open-file Report, 78-73-B,17 p., scale 1:250,000.

  • Deposit

    Berg, H.C., Elliott, R.L., and Koch, R.D., 1988, Geologic map of the Ketchikan and Prince Rupert quadrangles, southeastern Alaska: U.S. Geological Survey Mineral Investigations Series Map MF-1807,27 p., scale 1:250,000.

  • Deposit

    Karl, S.M., 1992, Map and table of mineral deposits on Annette Island, Alaska: U.S. Geological Survey Open-File Report 92-690, 57 p., 1 map, scale 1:63,360.

Comments on the references

  • Primary Reference = Berg, 1972 (I 684)

General comments

Subject category Comment text
Deposit Model Name = Disseminated sulfide deposit of undetermined origin.

Reporter information

Type Date Name Affiliation Comment
Reporter 07-JUL-1999 H.C. Berg U.S. Geological Survey