Unnamed (near Cascade Glacier)

Occurrence in Alaska, United States with commodities Copper, Silver, Gold
Sections on this page
  1. Identification information
  2. Geographic coordinates
  3. Site location context
  4. Geographic areas
  5. Commodities
  6. Materials information
  7. Host and associated rocks
  8. Nearby scientific data
  9. Economic information about the deposit and operations
  10. Mining district
  11. Links to other databases
  12. Bibliographic references
  13. General comments
  14. Reporter information

Geologic information

Identification information

Deposit ID 10002237
MRDS ID A013139
Record type Site
Current site name Unnamed (near Cascade Glacier)

Geographic coordinates

Geographic coordinates: -137.44101, 58.6636 (WGS84)
Relative position The occurrence is about 0.75 mile south of Cascade Glacier on a steep southwest-facing slope above Crillon Inlet. Iron-stained amphibolite crops out from about 3400 to 3600 foot elevation. The location is probably accurate to 0.15 mile. It is location 19 of Kimball and others (1978).

Site location context

Political divisions (FIPS codes)

Hoonah-Angoon(Census area)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Mount Fairweather C-5(quadrangle 1:63,360 scale)

Mount Fairweather NE(quadrangle 1:100,000 scale)

Mount Fairweather(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Glacier Bay(hydrologic unit)

Northern Southeast Alaska(hydrologic accounting unit)

Southeast Alaska(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

Glacier Bay National Park(National Park)

National Park NPS(Type of land area)

NPS(Federal land areas administered by NPS)

Geographic areas

Country State
United States Alaska

Commodities

Commodity Importance
Copper Primary
Silver Secondary
Gold Secondary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore
Pyrrhotite Ore

Host and associated rocks

  • Host or associated Host
    Rock type Metamorphic Rock > Schist

Nearby scientific data

(1) -137.44101, 58.6636

Economic information

Comments on the geologic information

  • Geologic Description = Amphibolite schist is extensively exposed in the Fairweather terrane of Brew and others (1978). The rocks probably are in the Chugach terrane of Berg and others (1972).? Amphibolite schist above Cascade Glacier is extensively iron-stained. The stain is developed on sulfidized (pyrite and pyrrhotite(?)) layers that crop out from about 3400 to 3600 feet elevation and are traceable along strike for 100s of feet. A float sample contained 1000 ppm copper. Samples representative of the schist unit contained elevated background amounts of copper--as much as 240 ppm (Kimball and others, 1978, p.C125). A heavily stained sulfide-rich lens about 0.4 feet thick and 10 feet long contained 800 ppm copper, 0.15 ppm gold and 7 ppm silver. (About 0.03 weight percent chalcopyrite is equivalent to 1000 ppm copper and chalcopyrite is the most likely copper phase in the unit.)? Kimball and others (1978) proposed that the site should be investigated more thoroughly. Iron-staining is widespread in the schistose units, and copper has been reported elsewhere in schist, as from the moraine coming out of North Crillon Glacier, where amphibolite-quartz schist fragments are stained with copper carbonates (MacKevett and others, 1971, p. 53 after Kennedy and Walton, 1946, p. 71). (The North Crillon location is 86 of plate 1 of MacKevett and others, 1971).
  • Age = Tertiary.

Economic information about the deposit and operations

Development status Occurrence
Commodity type Metallic

Comments on exploration

  • Status = Inactive

Mining district

District name Yakutat

Comments on the workings information

  • Workings / Exploration = There are no workings. Kimball and others (1978) followed up a USGS collected float sample which contained 1000 ppm copper. Select samples of the iron-stained schist contained as much as 7 ppm silver, 0.15 ppm gold, and 800 ppm copper.

Reference information

Bibliographic references

  • Deposit

    Kennedy, G.C. and Walton, M.S., Jr., 1946, Geology and associated mineral deposits of some ultrabasic rocks in southeastern Alaska: U.S. Geological Survey Bulletin 947-D, p. 65-84.

  • Deposit

    MacKevett, E.M., Jr., Brew, D.A., Hawley, C.C., Huff, L.C., and Smith, J.G., 1971, Mineral resources of Glacier Bay National Monument, Alaska: U.S. Geological Survey Professional Paper 632, 90 p., 12 plates, scale 1:250,000.

  • Deposit

    Berg, H.C., Jones, D. L., and Richter, D. H., 1972, Gravina-Nutzotin Belt-tectonic significance of an Upper Mesozoic sedimentary and volcanic sequence in southern and southeastern Alaska: U.S. Geological Survey Professional Paper 800-D, p. D1-D24.

  • Deposit

    Brew, D.A., Johnson, B.R., Grybeck, D., Griscom, A., Barnes, D.F., Kimball, A.L., Still, J.C., and Rataj, J.L., 1978, Mineral resources of the Glacier Bay National Monument Wilderness Study Area, Alaska: U.S. Geological Survey Open-File Report 78-494, 670 p.

  • Deposit

    Kimball, A.L., Still, J.C., and Rataj, J.L., 1978, Mineral resources, in Brew, D. A., and others, Mineral resources of the Glacier Bay National Monument wilderness study area, Alaska: U.S. Geological Survey Open-File Report 78-494, p. C1-C375.

Comments on the references

  • Primary Reference = Kimball and others, 1978

General comments

Subject category Comment text
Deposit Model Name = Mineralized amphibolite schist.
Deposit Other Comments = the area is extremely rugged; higher grade units could exist within the mineralized schist unit, an element of the Chugach terrane. The area is in Glacier Bay National Park and Preserve.

Reporter information

Type Date Name Affiliation Comment
Reporter 05-APR-99 Hawley, C.C. Hawley Resource Group

Beyond USGS

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

Authoritative Alaska resources

These are landing pages for further research — the state agencies don't currently expose per-mine deep links.