Unnamed (west of Williamsport)

Occurrence, Inactive

Commodities and mineralogy

Main commodities Fe
Other commodities Ti
Ore minerals magnetite

Geographic location

Quadrangle map, 1:250,000-scale IL
Quadrangle map, 1:63,360-scale C-3
Latitude 59.6757
Longitude -153.7583
Nearby scientific data Find additional scientific data near this location
Location and accuracy This occurrence is at an elevation of about 2,400 feet about 4.75 miles west-southwest of Williamsport on Iliamna Bay. The site is in the SE1/4 sec. 6, T. 6 S., R. 26 W., Seward Meridian. The location is accurate within about 0.5 mile. The occurrence is locality 25 of Detterman and Cobb (1972), and is briefly described by MacKevett and Holloway (1977).

Geologic setting

Geologic description

This occurrence comprises magnetite-bearing Jurassic mafic and ultramafic rocks that apparently are preserved as roof pendants in, or border phases of, a Jurassic quartz diorite batholith (Detterman and Reed, 1980). The mafic and ultramafic rocks include gabbro, hornblende gabbro, hornblendite, and pyroxenite. Magnetite occurs in veins, disseminations, and irregular lenses or pods. The deposit is similar to those at IL021, IL025, and IL027; it is probably large but relatively low grade (Berg and Cobb, 1967).
Geologic map unit (-153.760469746236, 59.6750436223125)
Age of mineralization Early or Middle Jurassic.

Production and reserves

Workings or exploration Berg and Cobb (1967) reported that the occurrence had been staked, but there are no reports of any workings.
Indication of production None

References