Lemhi Pass Area

Prospect in Lemhi county in Idaho, United States with commodities Thorium, Uranium, Copper
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Alteration
  7. Nearby scientific data
  8. Geologic structures
  9. Controls for ore emplacement
  10. Economic information about the deposit and operations
  11. Bibliographic references
  12. Reporter information

Geologic information

Identification information

Deposit ID 60000302
MRDS ID D003931
Record type District
Current site name Lemhi Pass Area

Geographic coordinates

Geographic coordinates: -113.4628, 44.93679 (WGS84)
Relative position DISTRICT LIES ASTRIDE THE CONTINENTAL DIVIDE IN EAST-CENTRAL BEAVERHEAD MOUNTAINS ALONG THE IDAHO-MONTANA BORDER. POINT LOCATION GIVEN ABOVE IS FOR THE LAST CHANCE MINE. THE DISTRICT ITSELF EXTENDS 3 1/2 MILES TO THE SW, 5 MILES TO THE SE, 4 MILES TO THE NORTH AND TWO MILES TO THE EAST AND TO THE WEST.

Site location context

Political divisions (FIPS codes)

Beaverhead(county)

Montana(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Lemhi Pass(quadrangle 1:24,000 scale)

Leadore(quadrangle 1:100,000 scale)

Dubois(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Red Rock(hydrologic unit)

Missouri Headwaters(hydrologic accounting unit)

Missouri Headwaters(hydrologic subregion)

Missouri(hydrologic region)

Federal lands

Beaverhead-Deerlodge National Forest(National Forest)

National Forest FS(Type of land area)

FS(Federal land areas administered by FS)

Geographic areas

Country State County
United States Idaho Lemhi
United States Montana Beaverhead

Commodities

Commodity Importance
Thorium Primary
Uranium Secondary
Copper Secondary

Alteration

  • (Local) SERICITIZATION

Nearby scientific data

(1) -113.4628, 44.93679

Economic information

Geologic structures

Type of structure Local
Structure name FAULTING
Structure description FAULTING OCCURED DURING TWO PERIODS: PRE-CHALLIS WHERE SMALL FAULTS TREND N25 - 40E, DIPPING STEEPLY NW, AND OTHERS TRENDING N15 - 20W. THE LONG YEARIAN FAULT (N 67 E, 68 SE) IS HORIZONTALLY OFFSET BY 6500 FT. POST CHALLIS FAULTING DEVELOPED THE LEMHI PASS (N70W STEEP), BULL MOOSE (N29-50W STEEP), AND DAN PATCH (N38W 50 - 90 SW) FAULTS. THESE THREE FAULTS CONVERGE AT THEIR NW TRENDS.
Type of structure Regional
Structure description BELT SERIES ROCKS REGIONALLY TREND SW AND DIP 20 TO 50 DEGREES GENERALLY TO THE NORTH.

Controls for ore emplacement

  • Fault/fracture

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Reference information

Bibliographic references

  • Deposit

    TRITES, A. F., AND TOOKER, E. W., 1953 , URANIUM AND THORIUM DEPOSITS IN EAST-CENTRAL IDAHO AND SOUTHWESTERN MONTANA: US GEOLOGICAL SURVEY BULL 988-H.

  • Deposit

    SHARP, W. N., AND CAUENDER, W. S., 1962 , GEOLOGY AND THORIUM BEARING DEPOSITS OF THE LEMHI PASS AREA, LEMHI CO., IDA., AND BEAVERHEAD CO., MONT.,: US GEOLOGICAL SURVEY BULL 1126 .

  • Deposit

    GEACH, R. D., 1972 , MINES AND MINERAL DEPOSITS (EXCEPT FUELS), BEAVERHEAD CO., MONTANA,: MONTANA BUR. OF MINES AND GEOLOGY, BULL 85 .

  • Deposit

    STAATZ, M. H., 1972 , GEOLOGY AND DESCRIPTION OF THE THORIUM BEARING VEINS, LEMHI PASS QUAD., IDAHO AND MONTANA: US GEOLOGICAL SURVEY BULL. 1351 .

Reporter information

Type Date Name Affiliation Comment
Reporter 01-DEC-1979 DOYLE, BRIEN (WELLS, JOHN) U.S. Geological Survey

Beyond USGS

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