Unnamed

Occurrence in Alaska, United States with commodity Copper

Geologic information

Identification information

Deposit ID 10308599
Record type Site
Current site name Unnamed

Geographic coordinates

Geographic coordinates: -147.44305, 63.08892 (WGS84)
Relative position This occurrence is at an elevation of about 3,800 feet, one mile due east of the center of the airstrip at Susitna Lodge. The map site is in the SW1/4 of sec. 18, T. 21 S., R. 2 E., of the Fairbanks Meridian. The location is accurate to about 250 feet.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary

Comments on the commodity information

  • Gangue = iron carbonate

Materials information

Materials Type of material
Azurite Ore
Bornite Ore
Chalcocite Ore
Malachite Ore
Epidote Gangue
Quartz Gangue

Alteration

  • Propylitic alteration of greenstone.

Nearby scientific data

(1) -147.44305, 63.08892

Comments on the geologic information

  • Geologic Description = The area of this occurrence is underlain by the Middle or Upper Triassic Nikolai Greenstone, a thick sequence of subaerial and submarine basalt flows and minor interbedded volcaniclastic sedimentary rocks, aquagene and epiclastic tuff, breccia, argillite, and radiolarian chert (Nokleberg and others, 1992). The deposit is in a hydrothermally altered shear zone in greenstone and consists quartz, epidote, bornite, chalcocite, and an iron carbonate mineral. Weathering produces malachite- and azurite-coated float and encrustations. Glavinovich (1967) described the occurrence as follows: 'Bornite, minor chalcocite and malachite occur as small discontinuous stringers in a narrow fracture zone. The fracture zone trends northeast, is about two inches wide and three feet in length. At both ends the zone narrows to a single fracture that continues along strike but is unmineralized. Gangue minerals include quartz and epidote. The paragenesis as determined in hand specimen is epidote, quartz, sulfides. The country rock is moderately altered andesite and is well jointed. Malachite coatings on joint faces are common.'
  • Age = Triassic or younger.

Economic information

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Valdez Creek

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF HE181

Bibliographic references

  • Deposit

    Glavinovich, P.S., 1967, Trace element copper distribution and areal geology in a portion of the Clearwater Mountains, Alaska: University of Alaska Minerals Industry Research Laboratory, Report 10, 55 p.

  • Deposit

    Nokleberg, W.J., and others, 1992, Circum-North Pacific terrane map, in Tracy, K.V., Anker, E. M., Ryan, C., Hoffman, V. , eds., International conference on Arctic margins, p. 44.

  • Deposit

    Kaufman, M.A., 1964, Geology and mineral deposits of the Denali-Maclaren River area, Alaska: Alaska Division of Mines and Minerals Geologic Report 4, 15 p., 1 sheet, scale 1:105,000.

Comments on the references

  • Primary Reference = Glavinovich, 1967

General comments

Subject category Comment text
Deposit Model Name = Hydrothermally altered shear zone

Reporter information

Type Date Name Affiliation Comment
Reporter 07-APR-2000 D.L. Stevens Stevens Exploration Management Corporation