Unnamed (on the Yentna Glacier)

Occurrence in Alaska, 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. Mineral occurrence model information
  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 10308445
Record type Site
Current site name Unnamed (on the Yentna Glacier)

Geographic coordinates

Geographic coordinates: -151.68083, 62.73653 (WGS84)
Relative position Reed and others (1978, locality 28) show the location of mineralized cobbles in moraine along the west limit of the Yentna Glacier in the northeast quarter of Section 34, T. 31 N, R. 13 W., of the Seward Meridian within Denali National Park and Preserve. This site is located approximately two and a half miles north-northeast of TL057.

Site location context

Political divisions (FIPS codes)

Matanuska-Susitna(Borough)

Alaska(state)

United States(country)

North America(continent)

Land(continent)

USGS map quadrangles

Talkeetna C-4(quadrangle 1:63,360 scale)

Talkeetna NW(quadrangle 1:100,000 scale)

Talkeetna C(quadrangle 1:250,000 scale)

Hydrologic units (watersheds)

Yentna River(hydrologic unit)

Susitna River(hydrologic accounting unit)

South Central Alaska(hydrologic subregion)

Alaska(hydrologic region)

Federal lands

Denali 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
Molybdenum Primary

Materials information

Materials Type of material
Chalcopyrite Ore
Molybdenite Ore
Pyrite Ore

Mineral occurrence model information

Model code 79
USGS model code 21a
Deposit model name Porphyry Cu-Mo
Mark3 model number 2
Model code 80
USGS model code 21b
Deposit model name Porphyry Mo, low-F

Nearby scientific data

(1) -151.68083, 62.73653

Economic information

Comments on the geologic information

  • Geologic Description = Granodiorite cobbles with fractures containing molybdenite, pyrite and minor chalcopyrite found at this site on the Yentna Glacier moraine are probably derived from the middle Tertiary (38 m.y.) Foraker pluton (Reed and others, 1978; Reed and Nelson, 1980). Minor malachite staining in Paleozoic sedimentary rocks is noted near the pluton contact. Further information that supports the Foraker pluton as the source of the float is anomalous copper (300 to 700 ppm) in a stream sediment and glacial debris sample taken from a site on the Yentna Glacier which drains the Foraker pluton (Curtin, Karlson, O'Leary, Day, and McDougal,1978). Use of a porphyry for this occurrence is not to suggest that a cobble with mineralized fractures is in itself a porphyry deposit. Instead, its possible affiliation with the Mt. Foraker pluton suggests that these veins could be a distal feature related to a concealed porphyry system. Not enough data exists to quantify this determination (Reed and others, 1978). This site is located approximately two and a half miles north-northeast of TL057 on the Yentna Glacier moraine.
  • Age = Middle Tertiary; mineralization is interpreted to be related to the 38 m.y. Foraker pluton (Reed and Nelson, 1980).

Economic information about the deposit and operations

Development status Occurrence

Comments on exploration

  • Status = Inactive

Mining district

District name Yentna

Comments on the workings information

  • Workings / Exploration = Reconnaissance mapping and rock sampling are all that have been done here (Reed and Nelson, 1980). Minor malachite staining in Paleozoic sedimentary rocks is noted near the pluton contact. Further information that supports the Foraker pluton as the source of the float is anomalous copper (300 to 700 ppm) in a stream sediment and glacial debris sample taken from a site on the Yentna Glacier which drains the Foraker pluton (Curtin, Karlson, O'Leary, Day, and McDougal,1978).

Reference information

Bibliographic references

  • Deposit

    Curtin, G.C., Karlson, R.C., O'Leary, R.M., Day, G.W., and McDanal, S.K., 1978, Geochemical and generalized geologic maps showing the distribution and abundance of gold and silver in the Talkeetna quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-870-E, 2 sheets, scale 1:250,000.

  • Deposit

    Reed, B.L., Nelson, S.W., Curtin, G.C., and Singer, D.A., 1978, Mineral resources map of the Talkeetna Quadrangle, Alaska: U.S. Geological Survey Miscellaneous Field Studies Map MF-870-D, 1 sheet, scale 1:250,000.

  • Deposit

    Reed, B.L., and Nelson, S.W., 1980, Geologic map of the Talkeetna quadrangle: U.S. Geological Survey Miscellaneous Investigations Map I-1174, scale 1:250,000.

  • Deposit

    MacKevett, E.M., Jr., and Holloway, C.D., 1977, Map showing metalliferous and selected non-metalliferous mineral deposits in the eastern part of southern Alaska: U.S. Geological Survey Open-File Report 77-169-A, 99 p., 1 sheet, scale 1:1,000,000.

Comments on the references

  • Primary Reference = Reed and others, 1978

General comments

Subject category Comment text
Deposit Model Name = Possibly related to Porphyry Cu-Mo (Cox and Singer, 1986; model 21a) or Porphyry Mo, Low-F (Cox and Singer, 1986; model 21b).
Deposit Other Comments = This site is within Denali National Park and Preserve.

Reporter information

Type Date Name Affiliation Comment
Reporter 10-AUG-98 Madelyn A. Millholland Millholland & Associates

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.