Webfoot

Prospect in Alaska, United States with commodities Gold, 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. 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 10000950
MRDS ID A011621
Record type Site
Current site name Webfoot
Alternate or previous names Reed and Fiske, Grimes
Related records 10233727

Geographic coordinates

Geographic coordinates: -149.2488, 61.81067 (WGS84)
Relative position On west side of upper Archangel Creek, marked with adit symbol and labeled 'Webfoot Prospect' on the Anchorage D-6 1:63,360-scale topographic map. Accurate within 400 ft. Locality 20 from Cobb (1972) and locality 17 of MacKevett and Holloway (1977).

Site location context

Political divisions (FIPS codes)

Matanuska-Susitna(Borough)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Anchorage D-6(quadrangle 1:63,360 scale)

Anchorage NW(quadrangle 1:100,000 scale)

Anchorage(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Lower 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
Gold Primary
Copper Secondary

Materials information

Materials Type of material
Gold Ore
Malachite Ore
Quartz Gangue

Alteration

  • (Local) Wall-rock alteration within a few inches of the veins is intense, but seldom extends more than 10 to 12 inches beyond the quartz filling. Sericitization and carbonate alteration predominate, but there is some pyritization and in the outer parts of the alteration zone chloritization is present (Ray, 1954). Sericitic alteration on vein margins (Kurtak, 1986).

Mineral occurrence model information

Model code 273
USGS model code 36a
Deposit model name Low-sulfide Au-quartz vein
Mark3 model number 27

Nearby scientific data

(1) -149.2488, 61.81067

Economic information

Comments on the geologic information

  • Geologic Description = A 2.5 to 5 ft wide auriferous quartz vein cuts the Late Cretaceous Willow Creek Pluton. The vein strikes due north and dips 33 to 40 W (Ray, 1954). Malachite staining was noted on some the quartz in dump (Capps, 1915). Kurtak (1986) reported that a 2.5-ft-wide chip sample across a quartz vien on the edge of a stope contained 0.44 ppm (0.013 oz/ton) Au, while a surface exposure contained 0.21 ppm ( 0.006 oz/ton) Au.? the Willow Creek Pluton is a zoned pluton: the outer part consists of hornblende quartz diorite and lesser hornblende tonalite; the core consists of hornblende-biotite granodiorite, and lesser hornblende-biotite quartz monzodiorite and biotite quartz monzonite. Wall-rock alteration within a few inches of the veins is intense, but seldom extends more than 10 to 12 inches beyond the quartz filling. Sericitization and carbonate alteration predominate, but there is some pyritization and in the outer parts of the alteration zone chloritization is present (Ray, 1954).
  • Age = Late Cretaceous or younger; vein cuts the Late Cretaceous Willow Creek Pluton.

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Willow Creek

Comments on the production information

  • Production Notes = No record of production (Cobb, 1972).

Comments on the workings information

  • Workings / Exploration = Vein explored by open cuts and about 300 ft of underground drifts. The ore is reported to be a large tonnage of low-grade material (Ray, 1954). Kurtak (1986) reported that a 2.5-ft-wide chip sample across a quartz vien on the edge of a stope contained 0.44 ppm (0.013 oz/ton) Au, while a surface exposure contained 0.21 ppm ( 0.006 oz/ton) Au.

Reference information

Bibliographic references

Comments on the references

  • Primary Reference = Ray, 1954

General comments

Subject category Comment text
Deposit Model Name = Low-sulfide Au-quartz veins (Cox and Singer, 1986; model 36a)
Deposit Other Comments = Capps (1915) refers to Webfoot or area very near Webfoot as the Grimes prospect and Katz (1911) uses the name Reed and Fiske.

Reporter information

Type Date Name Affiliation Comment
Reporter 30-JUL-1998 D.P. Bickerstaff U.S. Geological Survey
Reporter 30-JUL-1998 S.W. Huss U.S. Geological Survey

Beyond USGS

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

External references

Authoritative Alaska resources

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