Greathouse

Prospect in Alaska, United States with commodity Copper
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. Host and associated rocks
  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 10000722
MRDS ID A011361
Record type Site
Current site name Greathouse

Geographic coordinates

Geographic coordinates: -147.39775, 63.09156 (WGS84)
Relative position This prospect is at an elevation of about 5,000 feet, south of Windy Creek and about 2.6 miles east of Susitna Lodge. It is in sec.17,T. 21 S., R. 2 E., of the Fairbanks Meridian. The location is accurate to within 500 feet. The location is best shown in Kaufman (1964 GR-4, site 3) and in Smith (1981, site 28).

Site location context

Political divisions (FIPS codes)

Matanuska-Susitna(Borough)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Healy A-1(quadrangle 1:63,360 scale)

Mount Hayes SW(quadrangle 1:100,000 scale)

Healy(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Upper Susitna River(hydrologic unit)

Susitna River(hydrologic accounting unit)

South Central Alaska(hydrologic subregion)

Alaska(hydrologic region)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary

Materials information

Materials Type of material
Bornite Ore
Chalcocite Ore
Covellite Ore
Malachite Ore
Calcite Gangue
Epidote Gangue
Quartz Gangue

Alteration

  • (Local) The country rock has been epidotized adjacent to and along the shear zone.

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
  • Host or associated Host
    Rock type Volcanic Rock (Aphanitic) > Mafic Volcanic Rock > Basalt
    Rock unit name Nikolai Greenstone;Nikolai Greenstone
    Rock description Nikolai Greenstone;Nikolai Greenstone

Nearby scientific data

(1) Qs

Economic information

Comments on the geologic information

  • Geologic Description = The bedrock in the area of this prospect is the Triassic Nikolai Greenstone, a thick sequence of subaerial and submarine basalt flows, and minor interbedded volcaniclastic rocks, argillite, and radiolarian chert (Nokleberg and others, 1992).? the deposit consists of bornite, chalcocite, covellite, and malachite in a 3-foot-wide, northwest-trending shear zone. A chip sample across the zone contained 11% copper. The mineralized portion of the shear zone is less than 100 feet long, but the zone can be traced for more than 1,000 feet. Both the hanging wall and the footwall are altered basalt, and the brecciated country rock in the shear zone is strongly epidotized. A 4-foot-wide diorite dike cuts the basalt near the shear zone (Smith, 1981). Glavinovich (1967) noted that chalcocite replaces bornite, covellite replaces chalcocite, and quartz and malachite crosscut the sulfides. Several other northwest-trending shear zones occur in the area but are not known to contain any copper minerals. This prospect is in a broad belt of small copper occurences that extends east-northeast for approximately 10 miles along the south side of Windy Creek.
  • Age = Triassic or younger.

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Valdez Creek

Comments on the workings information

  • Workings / Exploration = No surface workings; chip samples across a 3-foot-wide section of the shear zone contained as much as 11% Cu (Kaufman, 1964).

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Kaufman, 1964 (ADGGS GR 4)

General comments

Subject category Comment text
Deposit Model Name = Mineralized shear zone.

Reporter information

Type Date Name Affiliation Comment
Reporter 07-APR-2000 D.L. Stevens Stevens Exploration Management Corporation

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.