Unnamed (in the canyon of Sheep Creek)

Occurrence in Alaska, United States with commodities Copper, Silver, Iron
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 10307854
Record type Site
Current site name Unnamed (in the canyon of Sheep Creek)

Geographic coordinates

Geographic coordinates: -153.87085, 62.41248 (WGS84)
Relative position This unnamed occurrence is located in a steep canyon of the west fork of Sheep Creek, on its east bank, at an elevation of 2,450 feet (746 m) in the SW1/4 sec. 23, T. 27 N., R. 25 W., of the Seward Meridian. The reporter visited the site in 1998 at station no. 98BT448.

Site location context

Political divisions (FIPS codes)

Yukon-Koyukuk(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

McGrath B-2(quadrangle 1:63,360 scale)

McGrath SE(quadrangle 1:100,000 scale)

McGrath(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Upper Kuskokwim River(hydrologic accounting unit)

Southwest(hydrologic subregion)

Alaska(hydrologic region)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Silver Secondary
Iron Secondary

Materials information

Materials Type of material
Marcasite Ore
Pyrite Ore
Quartz Gangue

Alteration

  • (Local) Strong silicification and sericite zones.

Mineral occurrence model information

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

Nearby scientific data

(1) -153.87085, 62.41248

Economic information

Comments on the geologic information

  • Geologic Description = This occurrence is a highly sulfidized, alteration zone in a rhyodacite unit of the Paleocene to Eocene, Sheep Creek Volcanic Field (Bundtzen, Harris, and Gilbert, 1997). A very distinct, ferricrete gossan occurs in a cliff wall on the east side of Sheep Creek; the incompetent, mineralized walls have partially caved into the creek channel. The mineralization consists of disseminated to massive pyrite-quartz veins and stockworks up to 2 meters in width. Strike lengths were not determined. The mineralized area averages about 25 percent pyrite. Grab samples of massive pyrite-quartz veins contained an average 15.5 percent iron, 255 ppm copper, and 0.45 ppm silver (T.K. Bundtzen and G.M. Laird, written communication, 1998).
  • Age = Mineralization is undated.

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 in 1981. Grab samples that contained massive pyrite-quartz stockwork veins yielded an average 255 ppm copper, 15.5 percent iron, and 0.45 ppm silver (T.K. Bundtzen and G.M. Laird, written communication, 1998).

Reference information

Comments on the references

  • Primary Reference = This description

General comments

Subject category Comment text
Deposit Model Name = Polymetallic veins (Cox and Singer, 1986; model 22c).

Reporter information

Type Date Name Affiliation Comment
Reporter 04-DEC-98 T.K. Bundtzen Pacific Rim Geological Consulting

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.