Unnamed (west of the Middle Fork Chandalar River)

Prospect in Alaska, United States with commodities Lead, Zinc, Silver, Copper
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Mineral occurrence model information
  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 10001728
MRDS ID A012512
Record type Site
Current site name Unnamed (west of the Middle Fork Chandalar River)

Geographic coordinates

Geographic coordinates: -147.87335, 68.02976 (WGS84)
Relative position Site is at approximately 3,850 ft., about 4 1/2 miles west of the Middle Fork Chandalar River and about 8 miles south-southwest of the confluence of Beaucoup Creek and Middle Fork Chandalar River (west-center sec. 25, T. 16 S., R. 18 E., of the Umiat Meridian). The site corresponds to sample No. 76 ARR 47 shown in Detra (1977, fig. 1). Location accurate within 1/4-mile radius.

Site location context

Political divisions (FIPS codes)

North Slope(Borough)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Philip Smith Mountains A-2(quadrangle 1:63,360 scale)

Arctic SW(quadrangle 1:100,000 scale)

Philip Smith Mountains(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Alaska(hydrologic region)

Federal lands

Arctic National Wildlife Refuge(National Wildlife Refuge)

National Wildlife Refuge FWS(Type of land area)

FWS(Federal land areas administered by FWS)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Lead Primary
Zinc Critical Primary
Silver Secondary
Copper Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Galena Ore
Sphalerite Ore
Tetrahedrite Ore
Barite Gangue
Quartz Gangue

Mineral occurrence model information

Model code 224
USGS model code 32a
Deposit model name Mississippi Valley, S.E. Missouri Pb-Zn
Mark3 model number 42

Host and associated rocks

  • Host or associated Host
    Rock type Sedimentary Rock > Chemical Sediment > Chert
    Rock unit name Skajit Limestone
    Rock description Skajit Limestone
    Stratigraphic age (youngest) Late Devonian

Nearby scientific data

(1) -147.87335, 68.02976

Economic information

Comments on the geologic information

  • Geologic Description = Visible sphalerite and galena occur in a Cu-stained and quartz-veined chert (Menzie and others, 1985). The occurrence is at the upper contact zone of Devonian - Silurian(?) Skajit Limestone with overlying shales, sandstones and conglomerates of the Devonian Hunt Fork Shale and Beaucoup Formation. The chert occurs locally along this contact. The upper contact of the Skajit in this location is an unconformity that has been interpreted as a paleokarst surface. Analysis of a sample of the mineralization from this occurrence returned values of 2 percent Pb, 0.5 to 1percent Zn, [more than] 0.5percent Ba and 30 ppm Ag (Detra, 1977).

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Chandalar

Comments on the workings information

  • Workings / Exploration = One block of 15 lode claims staked by RAA in 1977. Semi-quantitative spectrographic data from a rock sample (sample number 76 ARR 47) from the site gave the following values: Ag (30 ppm), Ba (greater than 5,000 ppm), Cd (70 ppm), Cu (1,000 ppm), Pb (20,000 ppm), Sb (300 ppm), Zn (10,000 ppm). Zn by wet chemical analysis - 5,000 ppm (Detra, 1977, table 1).

Reference information

Bibliographic references

  • Deposit

    Cathrall, J.B., Cooley, E.F., Detra, D.E., and O'Leary, R.M., 1977, A listing and statistical summary of spectrographic and chemical analysis of stream-sediment and rock samples from the Philip Smith Mountains quadrangle, Alaska: U.S. Geological Survey Open-File Report 77-244, 79 p.

  • Deposit

    Detra, D.E., 1977, Delineation of an anomalous lead-zinc area in the Philip Smith Mountains A-2 quadrangle, Alaska: U.S. Geological Survey Open-File Report 77-223, 11 p.

  • Deposit

    Barker, J.C., 1978, Mineral Investigations of certain lands in the eastern Brooks Range: a summary report: US Bureau of Mines Open-File No. 63-78

  • Deposit

    Dutro, J.T., Jr., 1978, Potential stratabound lead-zinc mineralization, Philip Smith Mountains quadrangle, Alaska, in Johnson, K. M., ed., The United States Geological Survey in Alaska, Accomplishments during 1977: U.S. Geological Survey Circular 772-B, p. B9-B11.

  • Deposit

    Brosgi, W.P., Reiser, H. N., Dutro, J. T., Jr., and Detterman, R. L., 1979, Bedrock geologic map of the Philip Smith Mountains quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-879-B, 2 sheets, scale 1:250,000.

  • Deposit

    Menzie, W.D., Reiser, H.N., Brosgi, W.P., and Detterman, R.L., 1985, Map showing distribution of mineral resources (excepting oil and gas) in the Philip Smith Mountains quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Investigations Map MF-879-C, 2 sheets, scale 1:250,000.

  • Deposit

    Schmidt, J.M., 1997, Shale-hosted Zn-Pb-Ag and barite deposits of Alaska, in Goldfarb, R.J., and Miller, L.D., eds., Mineral Deposits of Alaska, 1997: Economic Geology Monograph 9, p. 35-65.

  • Deposit

    Maas, K.M., 1987, Availability of land for Mineral exploration and development in northern Alaska, 1986: U.S. Bureau of Mines Special Publication, 34 p., 33 sheets.

Comments on the references

  • Primary Reference = Detra, 1977

General comments

Subject category Comment text
Deposit Model Name = Mississippi Valley Zn-Pb (?) (Cox and Singer, 1986; model 32a).
Deposit Other Comments = See also locations PS006 and PS007. Site is in an area of potential carbonate-hosted lead-zinc deposits (Menzie and others, 1985).

Reporter information

Type Date Name Affiliation Comment
Reporter 17-NOV-1999 J.M. Britton U.S. Geological Survey

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.