Unnamed (near Jones River)

Occurrence in Alaska, United States with commodities Copper, Iron

Geologic information

Identification information

Deposit ID 10307872
Record type Site
Current site name Unnamed (near Jones River)

Geographic coordinates

Geographic coordinates: -153.24384, 62.44549 (WGS84)
Relative position This unnamed occurrence is located on a northwest facing spur overlooking an unnamed tributary of Jones River; it is at an elevation of 4,900 feet (1,494 m) in the NW1/4 sec. 7, T. 27 N., R. 21 W., of the Seward Meridian. The reporter visited the site in 1984; at station no. 84BT113.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Iron Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore
Quartz Gangue

Mineral occurrence model information

Model code 85
USGS model code 22c
Deposit model name Polymetallic veins
Mark3 model number 46

Nearby scientific data

(1) -153.24384, 62.44549

Comments on the geologic information

  • Geologic Description = This unnamed occurrence is a thick, sulfide-bearing, quartz-vein breccia hosted in the mid Silurian Terra Cotta Mountains Sandstone, a unit of the Dillinger subterrane (Bundtzen, Harris, and Gilbert, 1997). The sulfide vein breccia zone averages about 45 meters wide, with individual veins and breccia zones subparallel to bedding in host sandstone and silty limestone. The zone strikes across a saddle in a northeasterly direction; it disappears into talus on both ends. Veins include an older anhedral variety of quartz that has been cut by younger euhedral quartz veins that introduced both chalcopyrite and pyrite. Breccia fragments of sedimentary country rock comprise about 15 percent of the vein material. Total sulfide content is estimated at about 1 percent of the total mineralized zone. No assay data is available. Metallic content is based on recognition of chalcopyrite and pyrite in the field.

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 for the Alaska Division of Geological and Geophysical Surveys in 1984. No assay data is available from the mineralized zone. Metallic content is based on recognition of chalcopyrite and pyrite in the field.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF MG075

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 vein (Cox and Singer, 1986; model 22c).

Reporter information

Type Date Name Affiliation Comment
Reporter 09-DEC-98 T.K. Bundtzen Pacific Rim Geological Consulting