Three Cub

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

Geologic information

Identification information

Deposit ID 10307756
Record type Site
Current site name Three Cub

Geographic coordinates

Geographic coordinates: -153.63698, 61.76537 (WGS84)
Relative position This occurrence is on the north side of a hanging-glacier moraine in the headwaters of an unnamed south tributary to uppermost Fish Creek. It is at an elevation of about 4,800 feet, 0.9 mile north of peak 6590. The map site is in the NE1/4 section 4, T 19 N, R 24 W, of the Seward Meridian. .This occurrence is sample locations 823 and 824 of Allen and others (1990), Allen and Slaughter (1990), and Allen (1991).
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Geographic areas

Country State
United States Alaska

Commodities

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

Comments on the commodity information

  • Gangue = carbonate

Materials information

Materials Type of material
Arsenopyrite Ore
Chalcopyrite Ore
Galena Ore
Pyrite Ore
Scheelite Ore
Sphalerite Ore
Stibnite Ore
Barite Gangue
Quartz Gangue

Alteration

  • (Local) Silicification and local calc-silicate skarn.

Mineral occurrence model information

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

Nearby scientific data

(1) -153.63698, 61.76537

Comments on the geologic information

  • Geologic Description = Thin, sulfide-bearing quartz veins, generally less than 15 cm wide, locally crosscut Jurassic or Lower Cretaceous graywacke and Upper Cretaceous or Tertiary granitic rocks at this locality (Allen, 1990; Allen and others, 1990; Allen and Slaughter, 1990). The veins consist dominantly of quartz, carbonate, pyrite, and arsenopyrite, and less commonly contain barite, chalcopyrite, stibnite, galena, and sphalerite. Some aplite dikes, quartz veins, and pyrite-bearing fracture surfaces in the granitic rocks contain scheelite and arsenopyrite. Calc-silicate skarn is very locally developed in sedimentary rocks adjacent to the granitic rock contacts. Quartz veins in graywacke contain as much as 1.3 ppm gold, 70 ppm silver, 3,000 ppm copper, and 500 ppm zinc. A sample from a sulfide-rich quartz-carbonate vein at a granitic rock contact contained 1.9 ppm gold, 150 ppm silver, 2,000 ppm arsenic, 150 ppm bismith, 1,000 ppm lead, 1,000 ppm antimony, 50 ppm tin, and 3,000 ppm zinc. Although scheelite has been reported in quartz veins from the general area, samples at this locality contained less than 20 ppm tungsten. The granitic rocks are part of the Alaska-Aleutian Range batholith (Reed and Lanphere, 1973).
  • Age = Late Cretaceous or Tertiary. The veins crosscut Upper Cretaceous or Tertiary granitic rocks of the Alaska-Aleutian Range batholith.

Economic information

Economic information about the deposit and operations

Development status Occurrence

Comments on exploration

  • Status = Inactive

Mining district

District name McGrath

Comments on the workings information

  • Workings / Exploration = Surface observation and sampling has occurred at this locality.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Alaska Resource Data File ARDF LH009

Bibliographic references

  • Deposit

    Reed, B. L., and Lanphere, M. A., 1973, Alaska-Aleutian Range batholith-- Geochronology, chemistry, and relation to circum-Pacific plutonism: Geological Society of America Bulletin, v. 84, no. 8, p. 2583-2610.

  • Deposit

    Nokleberg, W.J., and others, 1994, Metallogeny and major mineral deposits of Alaska and Metallogenic map of significant metalliferous lode deposits and placer districts of Alaska, in Plafker, G. and Berg, H.C., eds., The Geology of Alaska: Boulder, Colorado, Geological Society of America: The Geology of North America, v. G1, p. 855-904 and v. G1, Plate 11, scale 1:2,500,000.

  • Deposit

    Allen, M.S, 1990, Gold anomalies and newly identified gold occurrences in the Lime Hills quadrangle, Alaska , and their association with the Hartman sequence plutons, in Goldfarb, R. J., Nash, J. T., and Stoeser, J. W., eds., Geochemical studies in Alaska by the U.S. Geological Survey, 1989: U.S. Geological Survey Bulletin 1950, p. F1-F16.

  • Deposit

    Allen, M. S., Malcolm, M. J., Motooka, J. M., and Slaughter, K. E., 1990, Geologic description, chemical analyses, and sample locality map for rock samples collected from the eastern part of the Lime Hills quadrangle, Alaska: U.S. Geological Survey Open-File Report 90-69, 49 p..

  • Deposit

    Allen, M.S., and Slaughter, K. E., 1990, Mineralogical data and sample locality map of nonmagnetic, heavy-mineral-concentrate samples collected from the eastern part of the Lime Hills quadrangle, Alaska: U.S. Geological Survey Open-File Report 90-67, 64 p., 1 plate, scale 1:250,000.

Comments on the references

  • Primary Reference = Allen, 1991

General comments

Subject category Comment text
Deposit Model Name = Polymetallic veins (Cox and Singer, 1986, model 22c)

Reporter information

Type Date Name Affiliation Comment
Reporter 10-JUN-01 Travis L. Hudson Applied Geology
Reporter 10-JUN-01 Madelyn A. Millholland Millholland & Associates