Unnamed (north of Mt. Marchainville)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Fe; Ti
Other commodities Cu; Ni
Ore minerals chalcopyrite; ilmenite; magnetite; pyrrhotite

Geographic location

Quadrangle map, 1:250,000-scale MF
Quadrangle map, 1:63,360-scale B-4
Latitude 58.48
Longitude -137.02
Nearby scientific data Find additional scientific data near this location
Location and accuracy The occurrence is uncertainly located. It is either about two miles north of Mt. Marchainville at an elevation between 2500-3000 feet (NE 1/4, section 20, T 39 S., R. 51 E., of the Copper River Meridian) or about about 0.5 mile west-southwest of that location. The occurrence is number 83 of MacKevett and others (1971) and location 16 of Kimball and others (1978).

Geologic setting

Geologic description

Ilmenite and magnetite, accompanied by subordinate chalcopyrite and pyrrhotite, occur in heavily iron-stained masses near the south contact of the Crillon-LaPerouse layered mafic-ultramafic intrusion (Brew and others, 1978). The layered intrusive was emplaced in rocks of the Chugach terrane (Berg and others, 1972). The first reports of the occurrences were by Rossman (1963, B 1121-F); further reports were made by MacKevett and others (1971, p. 72-73) and Kimball and others (1978, p. C112).
Geologic map unit (-137.02190634935, 58.4796341683143)
Mineral deposit model Heavy-mineral segregations near basal contact of synorogenic layered mafic intrusive of Tertiary age (Foley and others, 1997).
Age of mineralization Tertiary.
Alteration of deposit Conspicuous secondary iron-staining.

Production and reserves

Workings or exploration Surface exposures only; knowledge is partly based on aircraft fly-by because of the extremely rough topography.
Indication of production None

Additional comments

The occurrences are in extremely rugged country in the south part of the Crillon-LaPerouse intrusion in Glacier Bay National Park and Preserve.

References

MRDS Number 10307808

References

Reporters C.C. Hawley (Hawley Resource Group)
Last report date 4/5/1999