Casey Glacier Sphalerite

Occurrence in Alaska, United States with commodities Lead, Zinc, Silver, Gold, Copper

Geologic information

Identification information

Deposit ID 10003616
MRDS ID A106373
Record type Site
Current site name Casey Glacier Sphalerite

Geographic coordinates

Geographic coordinates: -130.20454, 56.05171 (WGS84)
Relative position SEE LOCATION COMMENTS
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Geographic areas

Country State
United States Alaska

Comments on the location information

  • THE CASEY GLACIER SPHALERITE OCCURRENCE CONSISTS OF MINERALIZED BOULDERS OF FLOAT SCATTERED IN AN AREA OF ABOUT A QUARTER OF A SQUARE MILE (MAAS, 1995, P. 233, 235). THE OCCURRENCE IS IN THE NORTHEAST CORNER OF SECTION 23 BETWEEN ELEVATIONS OF ABOUT 3500 AND 4100 FEET, ON A NORTH-FACING MOUNTAINSIDE SOUTH OF THE WEST FORK OF TEXAS CREEK. IT IS ABOUT 2.0 MILES EAST OF TEXAS LAKE. THE ABOVE COORDINATES ARE FOR THE APPROXIMATE CENTER OF THE AREA OF FLOAT BOULDERS. THE LOCATION IS ACCURATE TO WITHIN ABOUT A QUARTER OF A MILE.

Commodities

Commodity Importance
Lead Primary
Zinc Primary
Silver Primary
Gold Primary
Copper Primary

Mineral occurrence model information

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

Nearby scientific data

(1) -130.20454, 56.05171

Ore body information

  • General form SEE DEPOSIT DESCRIPTION COMMENTS

Comments on the geologic information

  • LEAD-ISOTOPE STUDIES OF GALENA FROM THIS OCCURRENCE (MAAS AND OTHERS, 1995, P. 235) INDICATE THAT THE MINERALIZATION IS JURASSIC IN AGE, CONTEMPORANEOUS, AT LEAST IN PART, WITH ISLAND-ARC VOLCANISM IN HAZELTON TIME (ALLDRICK, 1993).

Economic information

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic
Significant No

Mining district

District name Hyder

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A106373
USGS Alaska Resource Data File ARDF BC085

Bibliographic references

  • Deposit

    Smith, J.G., 1977, Geology of the Ketchikan D1 and Bradfield Canal A-1 quadrangles, southeastern Alaska: U.S. Geological Survey Bulletin 1425, 49 p.

  • Deposit

    Alldrick, D. J., 1993, Geology and metallogeny of the Stewart mining camp, northwestern British Columbia: British Columbia Department of Mines and Petroleum Resources Bulletin no. 85, 105 p., 2 plates."

  • Deposit

    Maas, K. M., Bittenbender, P. E., and Still, J. C., 1995, Mineral investigations in the Ketchikan mining district, southeastern Alaska: U. S. Bureau of Mines Open-File Report 11-95, 606 p.

  • Deposit

    Koch, R. D., 1996, Reconnaissance geologic map of the Bradfield Canal quadrangle, southeastern Alaska: U.S. Geological Survey Open-File Report 81-728A, 35 p.,1 sheet, scale 1:250,000.

General comments

Subject category Comment text
Deposit THE COUNTRY ROCKS IN THE AREA OF THIS OCCURRENCE ARE PELITIC METASEDIMENTARY AND SUBORDINATE ANDESITIC METAVOLCANIC STRATA OF THE JURASSIC OR OLDER MESOZOIC HAZELTON GROUP, WHICH IS UNDERLAIN AND LOCALLY INTRUDED BY THE TRIASSIC TEXAS CREEK GRANODIORITE; AND THE EOCENE HYDER QUARTZ MONZONITE, WHICH INTRUDES THE HAZELTON AND TEXAS CREEK ROCKS (SMITH, 1977; KOCH, 1996). MAAS AND OTHERS (1995, P. 235, 246) DESCRIBE THE OCCURRENCE AS MINERALIZED FLOAT BOULDERS OF BRECCIATED HAZELTON ANDESITE CONTAINING MASSIVE BANDS AND VEINLETS OF SPHALERITE, GALENA, AND MINOR(?) PYRITE AND CHALCOPYRITE. THE SULFIDES CARRY SILVER AND A TRACE OF GOLD. INTENSE SILICA AND CARBONATE ALTERATION HAS ACCOMPANIED BRECCIATION AND MINERALIZATION. LEAD-ISOTOPE STUDIES OF GALENA FROM THIS OCCURRENCE (MAAS AND OTHERS, P. 235) INDICATE THAT THE MINERALIZATION IS JURASSIC IN AGE, CONTEMPORANEOUS, AT LEAST IN PART, WITH ISLAND-ARC VOLCANISM IN HAZELTON TIME (ALLDRICK, 1993).
Deposit ALTHOUGH NO OUTCROP OF THE BANDED SULFIDES WAS FOUND, THE LOCATION OF THE BOULDER RUBBLECROP SUGGESTS THAT THEIR SOURCE IS BENEATH THE ICEFIELD AT THE SUMMIT BETWEEN FERGUSON AND CASEY GLACIERS (MAAS, 1995, P. 235).

Reporter information

Type Date Name Affiliation Comment
Reporter 01-MAY-1998 Berg, H. C. U.S. Geological Survey