1. Mineral Resources
  2. Online Spatial Data
  3. Mineral Resource Data System (MRDS)

Unnamed (north wall Grinnell Glacier)

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

Geologic information

Identification information

Deposit ID 10307386
Record type Site
Current site name Unnamed (north wall Grinnell Glacier)

Geographic coordinates

Geographic coordinates: -144.78348, 60.72662 (WGS84)
Relative position This occurrence is at an elevation of about 2200 feet on the north wall of Grinnell Glacier. It is in SE1/4 sec. 24, T. 13 S., R. 3 E., of the Copper River Meridian. Site is accurately located to within 1000 ft. This location is site C-11 of 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 C-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
Copper Primary
Zinc Critical Secondary

Materials information

Materials Type of material
Arsenopyrite Ore
Chalcopyrite Ore
Malachite Ore
Pyrite Ore
Pyrrhotite Ore
Sphalerite Ore
Quartz Gangue
Sericite Gangue

Alteration

  • (Local) Local alteration of copper minerals.

Mineral occurrence model information

Model code 91
USGS model code 24b
Deposit model name Massive sulfide, Besshi (Japanese deposits)
Mark3 model number 30

Nearby scientific data

(1) -144.78348, 60.72662
ListMap

Economic information

Comments on the geologic information

  • Geologic Description = This occurrence consists of sulfide-bearing shear zones 2 to 10 feet wide in slate and greenstone of the Upper Cretaceous Valdez Group (Nelson and others, 1985). Ore minerals include arsenopyrite, chalcopyrite, malachite, pyrite, and pyrrhotite. Four chip samples collected and analyzed by the U.S. Bureau of Mines contained 255 ppm to 0.13% Cu; nine grab samples contained 13 ppm to 0.19% Cu (Jansons and others, 1984). This site is at the eastern end of a 65-mile-long belt of similar rocks that to the west host massive sulfide deposits (Nelson and others, 1984; 1985; Crowe and others, 1992). A massive-sulfide boulder found on the south side of Grinnel Glacier contained 30% pyrite, 3% chalcopyrite, 1% sphalerite in a quartz-sericite gangue (Kodosky and Teller, 1989). Assays of selected samples ranged from 1100 ppm to 1.8% Cu.
  • 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 examined during 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 also examined in 1988 by Kodosky and Teller (1989) for the Chugach Alaska Corporation. Their evaluation indicated some potential for copper mineralization. . Four chip samples collected and analyzed by the U.S. Bureau of Mines contained 255 ppm to 0.13% Cu; nine grab samples contained 13 ppm to 0.19% Cu (Jansons and others, 1984). A massive-sulfide boulder found on the south side of Grinnel Glacier contained 30% pyrite, 3% chalcopyrite, 1% sphalerite in a quartz-sericite gangue. Assays of selected samples ranged from 1100 ppm to 1.8% Cu.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Jansons and others, 1984

General comments

Subject category Comment text
Deposit Model Name = Besshi massive sulfide (Cox and Singer, 1986; model 24b)
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.

Maps centered on this site

Authoritative Alaska resources

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