The Unnamed (3850 Nunatak west of Tarr Inlet) is a copper mine located in Alaska.
About the MRDS Data:
All mine locations were obtained from the USGS Mineral Resources Data System. The locations and other information in this database have not been verified for accuracy. It should be assumed that all mines are on private property.
Mine Info
Satelite View
MRDS mine locations are often very general, and in some cases are incorrect. Some mine remains have been covered or removed by modern industrial activity or by development of things like housing. The satellite view offers a quick glimpse as to whether the MRDS location corresponds to visible mine remains.
Unnamed (3850 Nunatak west of Tarr Inlet) MRDS details
Site Name
Primary: Unnamed (3850 Nunatak west of Tarr Inlet)
Commodity
Primary: Copper
Secondary: Silver
Secondary: Zinc
Location
State: Alaska
District: Juneau
Land Status
Not available
Holdings
Not available
Workings
Not available
Ownership
Not available
Production
Not available
Deposit
Record Type: Site
Operation Category: Occurrence
Operation Type: Unknown
Years of Production:
Organization:
Significant:
Physiography
Not available
Mineral Deposit Model
Model Name: Porphyry Cu, skarn-related
Orebody
Not available
Structure
Not available
Alterations
Alteration Type: L
Alteration Text: Skarn developed in calc-magnesian rocks. Skarn minerals include garnet and epidote.
Rocks
Not available
Analytical Data
Not available
Materials
Ore: Chalcopyrite
Ore: Pyrite
Ore: Pyrrhotite
Gangue: Quartz
Comments
Comment (Exploration): Status = Inactive
Comment (Geology): Age = Tertiary.
Comment (Workings): Workings / Exploration = Surface occurrence only; samples of massive sulfide pods as much as 0.5 foot thick contained anomalous amounts of copper, zinc, and silver (Kimball and others, 1978, table C37, sample--location--number 27).
Comment (Deposit): Model Name = Skarn, massive sulfide -- similar to porphyry copper, skarn related (Cox and Singer, 1986; model 18a).
Comment (Deposit): Other Comments = Extensive ice cover which could conceal skarn- or porphyry copper-type deposits. The occurrence is in Glacier Bay National Park and Preserve.
Comment (Geology): Geologic Description = The occurrence area is extensively ice-mantled. Generally it is in an area where the country rocks are volcanic rocks of Permian age intruded by granitic rocks of Cretaceous age (Brew and others, 1978). At the occurrence, skarn-like pods of massive sulfide as much as 0.5 foot across occur in marble and volcanic rocks at a granitic contact. Silicate minerals in the skarn include actinolite, chlorite, diopside, epidote, and garnet. The sulfides are mainly pyrite and pyrrhotite, and minor chalcopyrite. Chip samples (Kimball and others, 1978, table C37, location 27) contained as much as 770 ppm copper, 190 ppm zinc, and 1.5 ppm silver.
Comment (Reference): Primary Reference = Kimball and others, 1978
References
Reference (Deposit): Brew, D.A., Johnson, B.R., Grybeck, D., Griscom, A., Barnes, D.F., Kimball, A.L., Still, J.C., and Rataj, J.L., 1978, Mineral resources of the Glacier Bay National Monument Wilderness Study Area, Alaska: U.S. Geological Survey Open-File Report 78-494, 670 p.
Reference (Deposit): Kimball, A.L., Still, J.C., and Rataj, J.L., 1978, Mineral resources, in Brew, D. A., and others, Mineral resources of the Glacier Bay National Monument wilderness study area, Alaska: U.S. Geological Survey Open-File Report 78-494, p. C1-C375.
The Top Ten Gold Producing States
These ten states contributed the most to the gold production that built the West from 1848 through the 1930s. The Top Ten Gold Producing States.
