Guide to the Chrome Mountain Area
Route
Start point
south flank of Chrome Mountain along Picket Pin-Iron Mountain Road
End point
east flank of Chrome Mountain along Picket Pin-Iron Mountain Road
Roads
U.S. Forest Service Road 140 (Picket Pin-Iron Mountain Road)
Total distance
~ 1 km
Geology
Summary
The Chrome Mountain area lies at nearly 10,000-feet elevation in the west-central part of the Stillwater Complex between the main part of the Boulder River and the headwaters of the East Boulder River. At Chrome Mountain, the olivine +/- bronzite +/- chromite cumulates of the Ultramafic Series are relatively well exposed and stratigraphically broadly resemble those at Mountain View. In addition, a distinctive rock type occurs: a fine-grained dunite which appears to have formed as a replacement of the ultramafic cumulates.
Key Lithologic Features
- various rocks of the Peridotite and Bronzitite zones, Ultramafic Series, including: cumulate ultramafic rocks, chromite seams, and discordant (secondary) dunite</li.
Structures
Landforms
Other Features
Reference
Raedeke, L.D., and McCallum, I.S., 1985, Guide to the Chrome Mountain area,
in Czamanske, G.K., and Zientek, M.L., eds.,
The Stillwater Complex, Montana: Geology and Guide : Montana Bureau of Mines and Geology Special Publication 92, p. 277-285.
Availability
Order from the Montana Bureau of Mines and Geology. Search for
this publication's record at the MBMG (more info) for ordering information.
