Unnamed (in tributary to the Tatina River)

Occurrence in Alaska, United States with commodities Zinc, Cadmium, Copper, Molybdenum

Geologic information

Identification information

Deposit ID 10307875
Record type Site
Current site name Unnamed (in tributary to the Tatina River)

Geographic coordinates

Geographic coordinates: -153.05283, 62.38049 (WGS84)
Relative position This unnamed occurrence is located in a steep, south-flowing, unnamed tributary of the Tatina River; it is at an elevation of 2,550 feet (777 m) in the SE1/4 sec. 31, T. 27 N., R. 20 W., of the Seward Meridian. The reporter visited the site in 1984; at station no. 84BT120.
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Geographic areas

Country State
United States Alaska


Commodity Importance
Zinc Primary
Cadmium Secondary
Copper Secondary
Molybdenum Secondary

Comments on the commodity information

  • Gangue = Iron oxides

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore


  • (Local) None.

Mineral occurrence model information

Model code 72
USGS model code 19a
Deposit model name Polymetallic replacement
Mark3 model number 47

Nearby scientific data

(1) -153.05283, 62.38049

Comments on the geologic information

  • Geologic Description = This unnamed occurrence is a mineralized gossan in shale of the Lower Cretaceous Kahiltna Flysch about 500 meters below the contact between the Upper Triassic to Lower Jurassic Tatina River Volcanics and Lower Cretaceous, Kahiltna Flysch (Bundtzen, Harris, and Gilbert, 1997). The gossan strikes east-west across a steep bedrock canyon subparallel to bedding and is about 3 meters thick; the strikelength was not measured. Disseminated chalcopyrite and pyrite were identified in one hand sample, but most mineralization is oxidized. One grab sample of mineralized shale contained 1,200 ppm zinc, 109 ppm copper, 9.3 ppm cadmium, and 7 ppm molybdenum.

Economic information

Economic information about the deposit and operations

Development status Occurrence

Comments on exploration

  • Status = Inactive

Mining district

District name McGrath

Comments on the workings information

  • Workings / Exploration = The reporter investigated the site during geologic mapping of the area in 1984 (Bundtzen, Harris, and Gilbert, 1997). One grab sample of mineralized shale contained 1,200 ppm zinc, 109 ppm copper, 9.3 ppm cadmium, and 7 ppm molybdenum.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF MG078

Bibliographic references

  • Deposit

    Bundtzen, T.K., Harris, E.E., and Gilbert, W.G., 1997, Geologic Map of the eastern McGrath quadrangle, Alaska: Alaska Division of Geological and Geophysical Surveys Report of Investigations 97-14, 34 pages, one sheet, scale 1:125,000.

Comments on the references

  • Primary Reference = This description

General comments

Subject category Comment text
Deposit Model Name = Polymetallic replacement (Cox and Singer, 1986; model 19a).

Reporter information

Type Date Name Affiliation Comment
Reporter 10-DEC-98 T.K. Bundtzen Pacific Rim Geological Consulting