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South Thomas

Producer in Mendocino county in California, United States with commodity Manganese
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Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Public Land Survey System information
  6. Commodities
  7. Materials information
  8. Host and associated rocks
  9. Nearby scientific data
  10. Economic information about the deposit and operations
  11. Ownership information
  12. Links to other databases
  13. Bibliographic references
  14. General comments
  15. Reporter information

Geologic information

Identification information

Deposit ID 10109253
MRDS ID M010043
Record type Site
Current site name South Thomas
Related records 10261495

Geographic coordinates

Geographic coordinates: -123.17053, 39.30626 (WGS84)
Elevation 457
Relative position 0.5 S. OF THOMAS MINE, E. SIDE OF RIDGE BETWEEN REDWOOD VALLEY AND POTTER VALLEY.

Site location context

Political divisions (FIPS codes)

Mendocino(county)

California(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Redwood Valley(quadrangle 1:24,000 scale)

Ukiah(quadrangle 1:100,000 scale)

Ukiah(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Russian(hydrologic unit)

Northern California Coastal(hydrologic accounting unit)

Klamath-Northern California Coastal(hydrologic subregion)

California(hydrologic region)

Geographic areas

Country State County
United States California Mendocino

Public Land Survey System information

Meridian Township Range Section Fraction State
Mount Diablo 017N 012W 27 California

Comments on the location information

  • LOCATED IN NE 1/4 SECTION 27

Commodities

Commodity Importance
Manganese Critical Primary

Materials information

Materials Type of material
Psilomelane Ore

Host and associated rocks

  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Shale
    Stratigraphic age (youngest) Late Cretaceous
    Stratigraphic age (youngest) Late Cretaceous
  • Host or associated Host
    Rock type Sedimentary Rock > Chemical Sediment > Chert
    Rock unit name Franciscan Complex
    Rock description Franciscan Complex

Economic information

Comments on the geologic information

  • ORE HOSTED IN FRANCISCAN COMPLEX--L. TO L. LENSES AND PODS OF RATHER HIGH-GRADE OXIDE ORE ARE FOUND, BUT MUCH OF THE ORE CONTAINS LARGE AMOUNTS OF WHITE CHERT. ORE THICKNESS VARIES FROM 1 FT. TO 2 FT. AND ORE IS NOT OF UNIFORM VALUE. ; GEOL.DESC: 2 PARALLEL BEDS OF MANGANESE ORE SEPARATED BY 15 FT. OF WELL-BEDDED RED CHERT. LENSES AND POCKETS OF HIGH GRADE OXIDE ORE ARE PRESENT. LOWER BED IS SHEARED AND CUT BY FRACTURES FILLED WITH BLACK OXIDE.

Economic information about the deposit and operations

Development status Producer
Commodity type Metallic
Deposit size Large
Significant No

Ownership information

  • Type Operator
    Owner Iva V. And Raymond H. Travis

Comments on the production information

  • ABOUT 1,500 TONS OF BLACK OXIDE ORE WERE SHIPPED FROM THIS MINE. MINE IDLE SINCE WORLD WAR I AND ROAD IS NOW IMPASSABLE.

Comments on the workings information

  • SHALLOW CUTS; TWO SHORT ADITS; OPEN CUT.

Reference information

Bibliographic references

  • Deposit

    CALIF. JOUR. MINES & GEOLOGY, V. 49, NO. 4, OCT., 1953, PP. 363, 390-391

  • Deposit

    D.O.M. BULL. 152, PP. 137-139

General comments

Subject category Comment text
Deposit LENSES AND PODS OF RATHER HIGH-GRADE OXIDE ORE ARE FOUND, BUT MUCH OF THE ORE CONTAINS LARGE AMOUNTS OF WHITE CHERT. ORE THICKNESS VARIES FROM 1 FT. TO 2 FT. AND ORE IS NOT OF UNIFORM VALUE.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JUN-1973 Gere, W. U.S. Geological Survey
Updater 01-DEC-1977 Killman, K.; Albers, J. U.S. Geological Survey

Beyond USGS

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

Maps centered on this site

Authoritative California resources

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