The Greenstone Mountain area, which includes the Utopia mining
district, is located in the foothills of the Pioneer Range, Beaverhead
County, Montana. Approximately 12, 600 feet of Paleozoic and
Mesozoic sedimentary rocks and an undetermined thickness of Precambrian
sediments and Late Cretaceous igneous rocks are exposed
within the area of...
The Pennsylvanian rocks in south-central Idaho and adjacent areas consist of three main facies: a platform facies, a shelf facies, and a marginal basin facies. The platform facies is represented by the Amsden, Quadrant, and Tensleep Formations, in southwestern Montana and western Wyoming, and contain Middle and probably Lower Pennsylvanian...
The Permian rocks near Quinn River Crossing, Humboldt County,
Nevada, crop out as a north-trending block-faulted ridge and consist
of more than 2600 feet of middle Permian fossiliferous limestone.
About 1000 feet of unfossiliferous cherty shales, sandstones, and
conglomerates are associated with the limestone and are assumed also
to be...
The thesis area consists of 42 square miles located
in Madison and Gallatin counties, Montana, in the southern
part of the Madison Range. The strata exposed in the
area range in age from Precambrian to Quaternary and have
an aggregate thickness of more than 7,600 feet.
The Paleozoic rocks, about...
The Cedar Creek area, consisting of about 30 square miles, is
located on the west flank of the central Madison Range in Madison
County, Montana.
The rocks of the area include carbonates, sandstones, mudstones,
cherts, phosphorite, metamorphic rocks, intrusive igneous
rocks, and unconsolidated sediments and have been divided into 16...
Fossil foraminifers from the Coaledo and Bastendorff Formations
near Coos Bay in southwestern Oregon were studied in an attempt
to determine the age and environment of deposition. Fresh unweathered
samples were collected from sea cliffs between Cape
Arago and Charleston, Oregon.
A large late Eocene delta is preserved in the...