Timberline

Prospect in Alaska, United States with commodities Silver, Gold, Copper

Geologic information

Identification information

Deposit ID 10000702
MRDS ID A011335
Record type Site
Current site name Timberline

Geographic coordinates

Geographic coordinates: -147.40387, 63.18769 (WGS84)
Relative position The site represents several prospects at an elevation of about 3,950 feet on the west slope of the ridge between Timberline Creek and Valdez Creek. The map site is in the N1/2 of sec. 17, T. 20 S., R. 2 E., of the Fairbanks Meridian. The location is accurate to within 1,000 feet. These prospects are shown as Sites 6 through 10 on Plate I of Smith, 1981.
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Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Silver Primary
Gold Primary
Copper Primary

Materials information

Materials Type of material
Arsenopyrite Ore
Chalcopyrite Ore
Gold Ore
Pyrite Ore
Pyrrhotite Ore
Calcite Gangue
Quartz Gangue

Alteration

  • (Local) The quartz veins are associated with chloritization of the adjacent diorite.

Mineral occurrence model information

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

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite
    Stratigraphic age (youngest) Late Cretaceous
    Stratigraphic age (youngest) Late Cretaceous
  • Host or associated Host
    Rock type Plutonic Rock > Mafic Intrusive Rock > Diorite

Nearby scientific data

(1) -147.40387, 63.18769

Comments on the geologic information

  • Geologic Description = The country rock in the area of this site is spotted phyllite, cut by CHLORITIZED DIORITE of probable Cretaceous age. The deposit consists of five veins in shear zones in altered diorite. The largest vein, the Big Caribou, has been traced for 1,000 feet; it is up to 8 feet wide, and contains kidneys and lenses of quartz, arsenopyrite, pyrite, pyrrhotite, and chalcopyrite. Other veins include the Big Water Hole, Freda G., Valdez Creek 6, and Little Caribou. Veins comprise quartz bands up to 2 feet wide. Some of the sulfides also are disseminated in the diorite. The veins appear to be localized in a conjugate fracture system associated with east-trending fault zones. Samples of the veins contain up to 0.33 ounce of gold per ton (Smith, 1981).
  • Age = Probably Cretaceous or younger.

Economic information

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 production information

  • Production Notes = A small mill was installed in about 1934; it consisted of a jaw crusher, ball mill, classifier, and amalgamating plates. Production was very small.

Comments on the workings information

  • Workings / Exploration = Surface exploration consists of trenches and pits along the traces of the veins. A short adit was driven which encountered the down-dip extension of the Big Caribou and Little Caribou vein systems. Samples of the veins contain up to 0.33 ounce of gold per ton (Smith, 1981).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A011335
USGS Alaska Resource Data File ARDF HE203

Bibliographic references

  • Deposit

    Ross, C.P., 1933, The Valdez Creek mining district, Alaska: U.S. Geological Survey Bulletin 849, p. 289-467.

  • Deposit

    Smith, P.S., 1934, Mineral industry of Alaska in 1933: U.S. Geological Survey Bulletin 864-A, p. 1-94.

  • Deposit

    Smith, P.S., 1936, Mineral industry of Alaska in 1934: U.S. Geological Survey Bulletin 868-A, p. 1-91.

  • Deposit

    Smith, P.S., 1937, Mineral industry in Alaska in 1935: U.S. Geological Survey Bulletin 880-A, p. 1-95.

  • Deposit

    Tuck, Ralph, 1938, The Valdez Creek mining district, Alaska, in 1936: U.S. Geological Survey Bulletin 897-B, p. 109-131.

  • Deposit

    Smith, T.E., 1971, Geology, economic geochemistry, and placer gold resources of the western Clearwater Mountains, east-central Alaska: Reno, University of Nevada, Ph.D. dissertation, 440 p.

  • Deposit

    Smith, T.E., 1981, Geology of the Clearwater Mountains, south-central Alaska: Alaska Division of Geological "&" Geophysical Surveys Geologic Report 60, 72 p., 3 sheets, scale 1:63,360.

  • Deposit

    Kaufman, M.A., 1964, Two new occurrences of ore minerals in the Denali area (Healy A-1 and Mt. Hayes B-6): Alaska Territorial Department of Mines Prospect Evaluation 67-4, 5 p.

Comments on the references

  • Primary Reference = Smith, 1981

General comments

Subject category Comment text
Deposit Model Name = Polymetallic veins (Cox and Singer, 1986, model 22c)
Deposit Other Comments = This was one of the very few lode gold producers in the Valdez Creek drainage.

Reporter information

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