Unnamed (north wall of Shiels Glacier)

Occurrence in Alaska, United States with commodities Lead, Zinc, Silver, Gold
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Mineral occurrence model information
  8. Nearby scientific data
  9. Economic information about the deposit and operations
  10. Mining district
  11. Links to other databases
  12. Bibliographic references
  13. General comments
  14. Reporter information

Geologic information

Identification information

Deposit ID 10307387
Record type Site
Current site name Unnamed (north wall of Shiels Glacier)

Geographic coordinates

Geographic coordinates: -144.76249, 60.87962 (WGS84)
Relative position This occurrence site is at an elevation of 2700 feet on the north wall of Shiels Glacier. It is in the SE1/4 sec. 30, T. 11 S., R. 4 E., of the Copper River Meridian. The location of the site is accurate to within 2000 ft. The occurrence is shown as site C-12 in Jansons and others (1984).

Site location context

Political divisions (FIPS codes)

Valdez-Cordova(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Cordova D-3(quadrangle 1:63,360 scale)

Cordova NE(quadrangle 1:100,000 scale)

Cordova(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Lower Copper River(hydrologic unit)

Copper River(hydrologic accounting unit)

South Central Alaska(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

Chugach National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Lead Primary
Zinc Critical Primary
Silver Secondary
Gold Secondary

Materials information

Materials Type of material
Galena Ore
Pyrite Ore
Pyrrhotite Ore
Sphalerite Ore

Mineral occurrence model information

Model code 90
USGS model code 24a
Deposit model name Massive sulfide, Cyprus
Mark3 model number 11
Model code 273
USGS model code 36a
Deposit model name Low-sulfide Au-quartz vein
Mark3 model number 27

Nearby scientific data

(1) -144.76249, 60.87962

Economic information

Comments on the geologic information

  • Geologic Description = The country rocks at this occurrence are metavolcanic rocks (greenstone) and metasedimentary rocks of the Upper Cretaceous Valdez Group. These rocks are part of a 65-mile-long belt of volcanic rocks having potential for volcanogenic massive sulfide deposits, extending to the Copper River (Nelson and others, 1984; 1985). The metavolcanic rocks contain disseminations and lenses of pyrite and pyrrhotite, and disseminations of galena and sphalerite. Two grab samples from talus contained 0.03 ppm and 5.0 ppm Au, 34 ppm and 0.92% Zn, 47 ppm and 0.20% Pb, and 5.4 ppm and 11.2 ppm Ag (Jansons and others, 1984). Pan-concentrate samples from the area contained 1000 ppm Au, 1000 ppm Ag, 1% As, and 3000 ppm Pb (Goldfarb and others, 1984). Kodosky and Teller (1989) report that the average gold value for pan-concentrate samples in this drainage is 5791 ppb. The average assays of two rock samples are 858 ppb and 1348 ppb Au, and 1750 ppm and 1038 ppm Pb.
  • Age = Late Cretaceous based on the age of the host rocks.

Economic information about the deposit and operations

Development status Occurrence

Comments on exploration

  • Status = Inactive

Mining district

District name Copper River

Comments on the workings information

  • Workings / Exploration = Site was sampled as part of a U.S. Bureau of Mines and U.S.G.S. mineral resource assessment of the Chugach National Forest (Jansons and others, 1984; Nelson and others, 1984). Site was also examined by private industry in 1988 (Kodosky and Teller,1989). Kodosky and Teller (1989) concluded that the drainage area had a very high probability of containing a gold-bearing quartz system. Their average gold value for pan-concentrate samples in this drainage is 5791 ppb. The average assays of two rock samples are 858 ppb and 1348 ppb Au, and 1750 ppm and 1038 ppm Pb.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Jansons and others, 1984

General comments

Subject category Comment text
Deposit Model Name = Cyprus massive sulfide (Cox and Singer, 1986; model 24a) and/or Chugach-type low-sulfide gold-quartz veins (Bliss, 1992; model 36a.1)
Deposit Other Comments = Chugach Alaska Corporation, Anchorage, Alaska has control of these lands.

Reporter information

Type Date Name Affiliation Comment
Reporter 10-JUN-00 S.W. Nelson U.S. Geological Survey

Beyond USGS

Supplemental information added by qvyshift.com. Not part of the original USGS MRDS record.

Authoritative Alaska resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.