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Melville Rhodes Mudge

Publications and source records attributed to Melville Rhodes Mudge.

At least 19 recordsLinked to original sources
USGS1980

The Lewis thrust fault and related structures in the Disturbed Belt, northwestern Montana

The classical Lewis thrust fault in Glacier National Park has now been mapped 125 km south of the park to Steamboat Mountain, where the trace dies out in folded middle Paleozoic rocks. The known length of the fault is 452 km, extending northward from Steamboat Mountain to a point 225 km into Canada, where the fault also dies out in Paleozoic rocks. At the south end, the surface expression of the Lewis thrust begins in a shear zone in folded Mississippian rocks. To the north, the thrust progressively cuts downsection into Proterozoic Y (Belt) rocks near Glacier National Park. Displacement on the Lewis plate increases northward from approximately 3 km on an easterly trending hinge line at the West Fork of the Sun River to a postulated 65 km at the southern edge of the park, where the stratigraphic throw is about 6,500 m. Present data indicate the thrust formed during very late Paleocene to very early Eocene time. The Lewis thrust and related structures, the Hoadley thrust and the Continental Divide syncline, probably formed concurrently under the same stress field. The northern limit of the trace of the Hoadley thrust is within the lower portion of the Lewis plate, about 28 km north of where the Lewis thrust develops, and the Hoadley extends for at least 125 km to the south. Displacement of the Hoadley increases southward from about 1 km at the hinge line to an inferred 70 km near its known southern extent. If our inference is correct, the Hoadley is nearly the southern mirror image of the Lewis to the north. The Continental Divide syncline, a doubly plunging, broad, northerly trending open fold that is about 120 km long, is a major fold within the Lewis plate.

Professional Paper↗
USGS1977

A summary of the mineral resources of the proposed Great Bear wilderness, Flathead, Teton, and Pondera counties, Montana

The proposed Great Bear wilderness has a good potential for oil and gas (mainly gas), and a moderate potential for submarginal resources of copper and silver in a belt 25 miles (40 km) long and about 1 mile (1.6 km) wide that is partly within the study area along the western boundary. The eastern part of the area may contain small submarginal resources of coal. Sand and gravel, dimension stone, and high calcium limestone are in the area, but they occur in abundance in more accessible areas elsewhere in northwest Montana. The potential for geothermal resources is nil. A mineral survey of the proposed Great Bear wilderness was made in 1974 and 1976. The work by the U.S. Geological Survey consisted of geologic mapping, and geochemical and geophysical surveys. The U.S. Bureau of Mines made a courthouse search for mining claims, and sampled and mapped prospects.

Montana↗