Main commodities | Cr; Fe |
---|---|
Ore minerals | chromite; magnetite |
Gangue minerals | serpentine |
Quadrangle map, 1:250,000-scale | SI |
---|---|
Quadrangle map, 1:63,360-scale | A-4 |
Latitude | 57.0691 |
Longitude | -135.2069 |
Nearby scientific data | Find additional scientific data near this location |
Location and accuracy | This occurrence is near elevation 2245 at the east end of the east spur of Arrowhead Peak. The occurrence is in the NE1/4SE1/4 sec. 27, T. 55 S., R. 64 E. It location 56 of Cobb (1972, 1978). The location probably is accurate within about 0.2 mile. |
Geologic descriptionThis occurrence is near the contact of two similar units of Jurassic and Triassic age (Loney and others, 1975). The Khaz Formation consists of graywacke, greenschist, metachert, phyllite, and minor limestone. The Kelp Bay Group consists of quartzite, greenschist, greenstone, graywacke and semischist, all of which are subject to intense cataclasis. The occurrence consists of magnetite and chromite in serpentine, which probably are small fault blocks or slivers (Loney and others, 1963). The serpentinite body is too small to be shown on the geologic map of Loney and other (1975). There is no indication that the occurrence is any more than accessory minerals in a small serpentinite body. Samples of diabase or greenstone collected by Loney and others (1963) show small amounts of chromium, nickel, copper, cobalt, and zinc that are little if any above normal background in these types of rocks. | |
Geologic map unit | (-135.208661412608, 57.0687389138763) |
---|---|
Mineral deposit model | Accessory magnetite and chromite in serpentine. |
Age of mineralization | Triassic or younger based on the age of the rocks in the area. |
Workings or exploration | Only surface sampling. |
---|---|
Indication of production | None |
MRDS Number | A013303 |
---|---|
References | |
Reporters | Donald Grybeck (U.S. Geological Survey) |
Last report date | 5/5/2005 |