Chill

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

Geologic information

Identification information

Deposit ID 10002176
MRDS ID A013073
Record type Site
Current site name Chill
Related records 10207846

Geographic coordinates

Geographic coordinates: -153.05274, 61.48254 (WGS84)
Relative position This prospect area is in the eastern headwaters of a large, east tributary to the Chilligan River. The map site is at an elevation of about 4,200 feet at the toe of glacial moraine that covers much of the headwater drainage. It is in the NW 1/4 section 16, T 16 N, R 21 W, of the Seward Meridian. This is locality 16 of Cobb (1972 [MF 412]; 1976 [OF 76-485]) and localities 27 and 28 of Gamble and others (1989). The location is probably accurate to within one-half mile.
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Geographic areas

Country State
United States Alaska

Commodities

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

Materials information

Materials Type of material
Arsenopyrite Ore
Chalcopyrite Ore
Galena Ore
Pyrite Ore
Pyrrhotite Ore
Sphalerite Ore
Quartz Gangue
Tourmaline Gangue

Alteration

  • (Local) Quartz-tourmaline veining and sulfide-rich replacement.

Mineral occurrence model information

Model code 53
USGS model code 17
Deposit model name Porphyry Cu
Mark3 model number 4
Model code 85
USGS model code 22c
Deposit model name Polymetallic veins
Mark3 model number 46

Host and associated rocks

  • Host or associated Associated
    Rock type Plutonic Rock > Granitoid > Granite
    Stratigraphic age (youngest) Pliocene
    Stratigraphic age (youngest) Pliocene
  • Host or associated Host
    Rock type Plutonic Rock > Granitoid > Granite

Nearby scientific data

(1) -153.05274, 61.48254

Comments on the geologic information

  • Geologic Description = Reed and Elliott (1970) reported several types of mineralization in this area, including: (1) tourmaline-chalcopyrite veins and fracture coatings in and near the contact zone between Tertiary monzonite-granite and country rock sandstone, (2) pyrite-arsenopyrite-chalcopyrite-galena-sphalerite veins in a fault zone that cuts granite, and (3) replacement of limestone by pyrite, pyrrhotite, as much as 5 percent chalcopyrite, and traces of galena. Mineralized float in the area includes (1) mafic rock with 30 percent chalcopyrite and pyrite, (2) tourmaline-quartz rock with 20 percent disseminated arsenopyrite, pyrite, and chalcopyrite, and (3) altered felsic rock with 3 percent disseminated pyrite and galena and limonite and malchite along fractures (Cobb and Reed, 1981). Samples of mineralized bedrock and float contained anomalous silver, copper, lead, tin, zinc, and traces of gold. The Chill claim group that was once located in this area covered a porphyry-type copper deposit and various sulfide-bearing veins. Samples from the general area contained up to 2.8 percent copper, 200 ppm silver, 25 ppm molybdenum, 3,250 ppm lead, 1,350 ppm zinc, and 0.2 ppm gold (Reed and Elliott, 1970; Cobb and Reed, 1981; Gamble and others, 1989). The country rocks are probably Mesozoic sedimentary rocks (Nokleberg and others, 1994) and the Tertiary granitic rocks are part of the Alaska-Aleutian Range batholith (Reed and Lanphere, 1973).
  • Age = Tertiary. Mineralization crosscuts Tertiary intrusive rocks or nearby, thermally metamorphosed sedimentary rocks.

Economic information

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Redoubt

Comments on the workings information

  • Workings / Exploration = Reconnaissance surface observation and sampling has been completed in this area (Reed and Elliott, 1970).

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A013073
USGS Alaska Resource Data File ARDF LH028

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

    Gamble, B.M., Bailey, E. A., and Reed, B. L., 1989, Gold occurrences near Snowcap Mountain, Lime Hills B-2 quadrangle, Alaska: U.S. Geological Survey Open-File Report 89-0646, 8 p.

  • 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

    Reed, B.L., and Elliott, R.L., 1970, Reconnaissance geologic map, analyses of bedrock and stream sediment samples, and an aeromagnetic map of parts of the southern Alaska Range: U.S. Geological Survey Open-File Report 70-217, 145 p., 1 sheet, scale 1:250,000. (Also published as U.S. Geological Survey Open-File Report 413).

  • Deposit

    Cobb, E.H., and Reed, B.L., 1981, Summaries of data on and lists of references to metallic and selected nonmetallic mineral occurrences in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska; Supplement to Open-File Report 76-485; Part A, Summaries to January 1, 1981: U.S. Geological Survey Open-File Report 81-1343-A, 25 p.

  • Deposit

    Cobb, E.H., 1976, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Iliamna, Lake Clark, Lime Hills, and McGrath quadrangles, Alaska: U.S. Geological Survey Open-File Report 76-485, 101 p.

  • Deposit

    Cobb, E.H., 1972, Metallic mineral resources map of the Lime Hills quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-412, 1 sheet, scale 1:250,000.

Comments on the references

  • Primary Reference = Gamble and others, 1989

General comments

Subject category Comment text
Deposit Model Name = Polymetallic veins and porphyry Cu (Cox and Singer, 1986, models 22c and 17)
Deposit Model Number = 17, 22c
Deposit Other Comments = This occurrence is within Lake Clark National Preserve.

Reporter information

Type Date Name Affiliation Comment
Reporter 10-JUN-2001 Travis L. Hudson Applied Geology
Reporter 10-JUN-2001 Travis L. Hudson Applied Geology