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Theses/Dissertations

1954

Boulder Batholith

Articles 1 - 3 of 3

Full-Text Articles in Geological Engineering

Geology Of An Area Near Montana City, Montana, Frank A. Crowley May 1954

Geology Of An Area Near Montana City, Montana, Frank A. Crowley

Bachelors Theses and Reports, 1928 - 1970

The investigated area lies about five miles south of Helena, Montana, near the abandoned gold camp of Montana City. Topographically, the area reflects the sedimentary formations and the igneous rocks, quartz monzonite and rhyolite. Static recrystallization of the sedimentary rocks caused by the intrusion of the Boulder Batholith, along with deformation of sedimentary beds by pre-batholithic folding and by post-batholithic faulting have complicated the geologic picture.


The Placer Deposits Of The Siberia District (German Gulch), Montana, Ronald D. Karvinen May 1954

The Placer Deposits Of The Siberia District (German Gulch), Montana, Ronald D. Karvinen

Bachelors Theses and Reports, 1928 - 1970

The original concept of this problem was to determine if hidden or buried placers existed past the terminal point of the extensive placering in the Siberia District. Several theories have been advanced for the sudden cessation of those placers. All are plausible, and are both for and against an extended placer. The past history relates that some $13,000,000 in gold has been produced in the area, therefore stressing a practical search for additional accumulation.


Geology Of A Mineralized Breccia "Pipe" Near Basin, Montana, James W. Allan May 1954

Geology Of A Mineralized Breccia "Pipe" Near Basin, Montana, James W. Allan

Bachelors Theses and Reports, 1928 - 1970

Located on the western flank of the Boulder batholith of southwestern Montana, the mineralized breccia "pipe" is opened by the Obelisk Mine. The intersection of two fault systems in the quartz monzonite of the Boulder batholith has provided the locus of the breccia "pipe". There is fairly conclusive evidence indicating that the present outcrop of the "pipe" lies only a few hundred feet below the former "roof" of the batholith.