Red Hills Prospect

Prospect in Presidio county in Texas, United States with commodities Copper, Molybdenum
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. Host and associated rocks
  10. Nearby scientific data
  11. Economic information about the deposit and operations
  12. Mining district
  13. Land status
  14. Reserves and resources
  15. Links to other databases
  16. Bibliographic references
  17. General comments
  18. Reporter information

Geologic information

Identification information

Deposit ID 10085727
MRDS ID W701360
Record type Deposit
Current site name Red Hills Prospect

Geographic coordinates

Geographic coordinates: -104.40218, 29.804 (WGS84)
Relative position 5 MI (8 KM) W OF SHAFTER

Site location context

Political divisions (FIPS codes)

Presidio(county)

Texas(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Cerro Orona(quadrangle 1:24,000 scale)

Presidio(quadrangle 1:100,000 scale)

Presidio(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Cibolo-Red Light(hydrologic unit)

Rio Grande-Amistad(hydrologic accounting unit)

Rio Grande-Amistad(hydrologic subregion)

Rio Grande(hydrologic region)

Geographic areas

Country State County
United States Texas Presidio

Comments on the location information

  • THE PROPERTY IS LOCATED 1 MI (1.6 KM) SOUTH OF THE SOUTHERN WALL OF THE CHINATI MOUNTAINS CALDERA.

Commodities

Commodity Importance
Copper Primary
Molybdenum Primary

Materials information

Materials Type of material
Chalcopyrite Ore
Chalcocite Ore
Sphalerite Ore
Quartz Gangue
Pyrite Gangue
Garnet Gangue

Alteration

  • (Local) Outcropping Sericite (Central) And Propylitic (Exterior) Alteration; Skarn From Limestone
  • (Local) potassic
  • (Local) phyllic
  • (Local) propylitic
  • (Local) argillic
  • (Local) skarn

Mineral occurrence model information

Model code 53
USGS model code 17
Deposit model name Porphyry Cu
Mark3 model number 4

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid > Quartz Monzonite
    Rock unit name Intrusions
    Rock description Intrusions
    Chronological age 64
    Dating method U-Pb (zircon)
  • Host or associated Host
    Rock type Sedimentary Rock > Mixed Clastic/Carbonate Rock
    Rock type qualifier Shale, sandstone, limestone. Upper part alternating sh and ss, lenses of ls. below this thin interbeds of ss and chert. in lower part alternations of ss and sh; ss med-grained, indurated, thinly bedded; shale silty laminted, fissil, black, 727 ft thick
    Rock unit name Ross Mine Formation
    Rock description Ross Mine Formation;
    Stratigraphic age (youngest) Guadalupian
    Stratigraphic age (oldest) Guadalupian
  • Host or associated Host
    Rock type Metamorphic Rock > Skarn (Tactite)
  • Host or associated Host
    Rock type Sedimentary Rock > Carbonate > Limestone
    Rock type qualifier Limestone, hard massive, dolomitic, reefy, surface rough and hackly with brecciated appearance, gray to yellowish brown. Thickness up to 400 ft in Shafter district, missing in many places due to pre-Cretaceous erosion.
    Rock unit name Mina Grande Formation
    Stratigraphic age (youngest) Guadalupian
    Stratigraphic age (oldest) Guadalupian
  • Host or associated Associated
    Rock type Sedimentary Rock > Mixed Clastic/Carbonate Rock
    Rock type qualifier Conglomerate, limestone, sandstone, siltstone. A basal well-indurated pebble to boulder conglomerate, 30-80 ft thick grades upward to sandstone and siltstone, overlain by impure carbonate rocks, calcar sandst, and siltstone, thickness 436 ft.
    Rock unit name Presdio Formation
    Stratigraphic age (youngest) Albian
    Stratigraphic age (oldest) Aptian

Nearby scientific data

(1) -104.40218, 29.804

Economic information

Comments on the geologic information

  • THE PROPERTY IS LOCATED 1 MI (1.6 KM) SOUTH OF THE SOUTHERN WALL OF THE CHINATI MOUNTAINS CALDERA. OUTCROPPING SKARN CONTAINS GROSSULAR-ANDRADITE, DIOPSIDE, TREMOLITE, CALCITE, QUARTZ, AND CHALCOPYRITE AND IS RICH IN COPPER (UP TO 0.42%) AND ZINC (0.20%). A STOCKWORK QUARTZ-PYRITE-SERICITE ZONE, RICH IN COPPER (0.17%) AND MOLYBDENUM (0.028%), IS 2,300 FT (700 M) IN DIAMETER AND IS CENTERED ON A QUARTZ PORPHYRY INTRUSION THAT IS LOCALLY A COMPLEX INTRUSIVE BRECCIA. ALUNITE IS ABUNDANT ON THE SURFACE, PRESUMABLY AS A SUPERGENE PHASE. BOTH THE STOCKWORK-VEINED PORPHYRY AND SKARN ARE ANOMALOUS IN SILVER (UP TO 2 PPM).
  • From Gilmer and others 2001: 40Ar/39Ar analyses of sericite indicate an early Tertiary age of alteration. Fluid inclusion studies of quartz veins indicate that the fluids associated with phyllic alteration had a mean temperature of 399?C ? 58?C based on measured homogenization temperatures. Pressure estimates based on contemporaneous trapping of immiscible fluids indicate a range of formation pressures from 20 to 30 MPa, corresponding to depths of formation of 2 to 3 km.

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic
Significant Yes

Mining district

District name Shafter Silver District

Land status

Ownership category Private

Comments on the production information

  • PRODUCTION: NONE, EXCEPT TWO CARLOADS OF MALACHITE-AZURITE TAKEN BY ROBERT I. CARR OF SHAFTER BEFORE 1953.

Reserves and resources

  • Type In-situ
    Estimate year 1999
    Total resources 18000000
    Remarks Silver, D.B., 1999, Finding the silver lining in Shafter, Texas: Mining Engineering, v. 51, p. 28-32.Gilmer, A.K., Kyle, J.R., Connelly, J.N., Mathur, R.D. and Henry, C.D., 2003, Extension of Laramide magmatism in southwestern North America into Trans-Pecos Texas; Geology, v. 31, p. 447-450.
    Commodity Subtype Grade units Group Importance Year
    Copper Cu 0.35 wt-pct Copper Primary 1999

Comments on the reserve resource information

  • RESOURCES AND GRADE: UNCERTAIN.

Comments on the workings information

  • 87 drill holes reported Oct. 31, 1995 (http://www.infomine.com/index/properties/RED_HILLS_-_SILVER_ASSETS.html).

Comments on development

  • EXPLORATION BY DUVAL CORP. IN RECENT DECADES: PIONEER NUCLEAR AND AMAX EARLIER.

Reference information

Bibliographic references

General comments

Subject category Comment text
Deposit ONLY MINOR AMOUNTS OF SKARN.

Reporter information

Type Date Name Affiliation Comment
Reporter 01-JAN-1991 Paidakovich, Matthew E. U.S. Geological Survey
Updater 01-MAR-1993 Long, Keith R. U.S. Geological Survey
Updater 20-JUL-2009 Causey, J. Douglas U.S. Geological Survey

Beyond USGS

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