Prospect in Alaska, United States with commodity Copper

Geologic information

Identification information

Deposit ID 10093977
MRDS ID A011314
Record type Site
Current site name Jumbo

Geographic coordinates

Geographic coordinates: -149.61283, 63.23958 (WGS84)
Relative position The Jumbo prospect is at an elevation of about 2,200 feet on the south bank of the West Fork Chulitna River, about 0.5 mile from the junction of Bryn Mawr Creek. It is in sec. 26, T. 19 S., R. 11 E., of the Fairbanks Meridian. The location is accurate to within 1 mile. This is locality 7 of Cobb (1978: OFR 78-1062). According to Capps (1919), the Jumbo prospect adjoins the Riverside prospect (HE033).
(click for info)

Geographic areas

Country State
United States Alaska


Commodity Importance
Copper Primary

Materials information

Materials Type of material
Chalcopyrite Ore
Pyrite Ore
Pyrrhotite Ore
Quartz Gangue

Mineral occurrence model information

Model code 58
USGS model code 18a
Deposit model name Porphyry Cu, skarn-related
Mark3 model number 9

Host and associated rocks

  • Host or associated Host
    Rock type Sedimentary Rock > Clastic Sedimentary Rock > Conglomerate

Nearby scientific data

(1) -149.61283, 63.23958

Comments on the geologic information

  • Geologic Description = Bunches and specks of sulfides, mainly pyrrhotite along with some pyrite and chalcopyrite, are disseminated in Triassic conglomerate adjacent to a porphyry dike. The dike is similar in composition to the Upper Cretaceous porphyry at the Golden Zone mine (HE043).
  • Age = Probably Late Cretaceous or younger.

Economic information

Economic information about the deposit and operations

Development status Prospect
Commodity type Metallic

Comments on exploration

  • Status = Active

Mining district

District name Valdez Creek

Comments on the workings information

  • Workings / Exploration = Only open-cut surface workings.

Reference information

Links to other databases

Agency Database name Acronym Record ID Notes
USGS Mineral Resources Data System MRDS A011314
USGS Alaska Resource Data File ARDF HE034

Bibliographic references

  • Deposit

    Cobb, E.H., 1978, Summary of references to mineral occurrences (other than mineral fuels and construction materials) in the Healy quadrangle, Alaska: U.S. Geological Survey Open-File Report 78-1062, 113 p.

  • Deposit

    Capps, S.R., 1919, Mineral resources of the upper Chulitna region: U.S. Geological Survey Bulletin 692-D, p. 207-232.

Comments on the references

  • Primary Reference = Capps, 1919

General comments

Subject category Comment text
Deposit Model Name = Cu porphyry (Cox and Singer, 1986; model 18a)

Reporter information

Type Date Name Affiliation Comment
Reporter 07-APR-2000 N. Van Wyck Stevens Exploration Management Corporation