Unnamed Occurrence (ARDF - MF018; west of Mt. Fairweather), Yakutat Mining District, Yakutat, Alaska, USAi

Regional Level Types
Unnamed Occurrence (ARDF - MF018; west of Mt. Fairweather)	- not defined -
Yakutat Mining District	Mining District
Yakutat	City Borough
Alaska	State
USA	Country

The site is in Glacier Bay National Park and Preserve. Further exploration would need mountaineering support.
Location: The occurrence is on the west contact of the Mt. Fairweather mafic intrusion about 3.7 miles bearing about 263 degrees (true azimuth) from the top of Mt. Fairweather. The location has not been occupied, but there are conspicuous copper (malachite?) stains both in the intrusion and the country rocks in the contact zone. The mineralization may extend north along the contact, because sulfide boulders were found on Sea Otter Glacier to the north, as well as on the glacier between Sea Otter and Fairweather Glaciers.
Geology: This occurrence, and the occurrence of detrital mineralized mafic rocks in nearby glacial moraine (MF016 and MF017), suggests that there may be (a) Brady Glacier-type nickel-copper deposits in the Mount Fairweather layered mafic-ultramafic intrusion and (b) contact-type copper deposits in the schist country rocks. The inferred mineral deposits are in or at the contact of the Mt. Fairweather layered mafic intrusion, the northern-most of four layered mafic complexes of the Fairweather Range (Brew and others, 1978). The primary copper sulfides exposed at or near the contact have locally been oxidized to malachite, forming copper-stained zones visible from aircraft fly-by. The sites have not been occupied.
Workings: Helicopter reconnaissance reported in Kimball and others (1978, Fig. C-34, p. C117-C118) found conspicuous copper staining near the western contact of the Mt. Fairweather intrusion. No landings were possible.
Age: Tertiary.
Alteration: Local secondary alteration of copper-bearing minerals.

Commodities (Major) - Cu, Ni?; (Minor) - Co?, Cr?, PGE?, Ti?
Deposit Model: Cumulate or sulfide segregations in layered-mafic intrusions. Contact deposits i

Other Databases

Link to USGS - Alaska:	MF018

Other Regions, Features and Areas containing this locality

References