Geology topics
Research about Montana
Source-linked reports with geographic coverage including Montana.
Reconnaissance geologic map of the St. Regis-Superior area, Mineral County, Montana
No abstract available.
Uranium in carbonaceous rocks in the Townsend and Helena valleys, Montana
Uranium-bearing carbonaceous shale and lignite beds are exposed in five areas in the Townsend and Helena Valleys in western Montana. The greatest number of exposures is in an area of several square miles northeast of Winston in the Townsend Valley. The uranium-bearing beds are in the lower part of a Tertiary unit that consists largely of thin-bedded, white to buff, pure and impure tuffs, locally altered to bentonite. The uranium occurrences, none of which appear to be commercial, have three characteristics in common: (1) they are in and adjacent to carbonaceous shale or lignite interbedded with light-gray of white, fine-grained tuffs and lapilli tuffs, (2) the stratigraphic section in the vicinity of the deposits includes bentonite and partly bentonized tuff, and (3) the distribution of the uranium in the favorable beds is erratic. The uranium was probably leached from the tuffs and lapilli tuffs by meteoric water during bentonization and was concentrated in the carbonaceous shale and lignite. Similar Tertiary rocks are present in many of the major valleys in Western Montana and probably warrant prospecting for uranium. Areas containing white, fine-grained tuff or lapilli tuff, bentonite, and coal, or carbonaceous shale would be particularly favorable for prospecting.
Geology and ground-water resources of the lower Yellowstone River valley, between Glendive and Sidney, Montana
No abstract available.
Geology and occurrence of ground water in the Townsend Valley, Montana
No abstract available.
Age determinations on some rocks from the Boulder batholith and other batholiths of Western Montana
No abstract available.
Chromite deposits in the central part of the Stillwater complex, Sweet Grass County, Montana
No abstract available.
Physical stratigraphy of the Phosphoria formation in part of southwestern Montana
No abstract available.
Preliminary geologic map of the Goose Mountain No. 1 quadrangle, Montana
No abstract available.
Preliminary geologic map of the Goose Mountain No. 2 quadrangle, Montana
No abstract available.
Preliminary geologic map of the Lonesome Lake No. 2 quadrangle, Montana
No abstract available.
Water levels in observation wells in part of Montana, 1946-1953
Ground-water investigations were made by the Ground Water Branch, U. S. Geological Survey, from 1946 to 1954, inclusive, in several parts of Montana. These studies were made as part of the program of the Department of the Interior for development of the Missouri River Basin. Thus, the areas selected for study were principally those in which construction agencies such as the U.S. Bureau or Reclamation and the U. S. Bureau of Indian Affairs had problems relating to ground water. Figure 1 shows the areas in Montana in which ground-water studies have been made under the Missouri Basin Program from 1946 to 1954, inclusive.