Geology topics
Research about Montana
Source-linked reports with geographic coverage including Montana.
Supplemental data from the Ennis and other thermal-springs areas, Southwestern Montana, 1978-80
Hydrogeologic data were collected principally during 1978-80 in eight hot-spring areas, in the Marysville geothermal test well, in the Butte Mine and in the Bitterroot and Missoula River valleys to provide a basis for evaluating the geothermal potential of the areas. Measurements are tabulated for subsurface temperatures, water levels, rates of flow, and the chemical composition of water and gas in wells and test holes. Most of the data are for the area near Ennis Hot Springs.
Survey of helium in natural water wells and springs in southwest Montana and vicinity; Part II
This report is a continuation of the work on a helium survey presented in Open-File Report 80-181, which covered the period Sept., 1977 - June 30, 1979. Water samples were analyzed for helium collected from twelve springs and wells, of which four are new locations. A brief description of these stations is given in Table 1 and their location is shown on the map of Figure 1. Two springs (303 and 304) previously reported on do not appear in this report. Station 306 was discontinued after August 11.
Chemical analyses of stream deposits in the West Pioneer Mountains, Beaverhead County, Montana
The U.S. Geological Survey commenced a mineral-resource assessment of the West Pioneer Mountains, Montana in 1970. The study consists of coordinated geological, geochemical, and geophysical studies with the objective of evaluating the potential for mineral deposits in the area. The geochemical survey consists of the collection of bulk stream sediments which are analyzed for 31 elements using wet chemical and semiquantitative emission spectrographic techniques. The purpose of this report is to present the chemical analyses of the stream sediments collected to date.
Lemhi Pass drilling project, Montana
The Lemhi Pass district has the largest thorium resources of any vein district in the United States (Staatz and others, 1979, p. 10). Most of the resources occur in veins that have an average grade of between 0.1 and 2.0 percent Th0 2 . More than 200 thorium-bearing veins have been mapped in this district (Staatz, 1979, p. A34). The Lemhi Pass thorium district lies astride the Continental Divide in the east-central part of the Beaverhead Mountains along the Idaho-Montana State line. Although the area in which thorium veins are found covers more than 150 square miles, the drilling project was confined to three veins in the northwestern part of this district on the Montana side of the Continental Divide (fig. 1). An unimproved dirt road that crosses the Continental Divide at Lemhi Pass furnishes access to the drilling area. This road connects Idaho State Highway 28 at Tendoy, Idaho, 13 miles west of Lemhi Pass, with Interstate Highway 15 at the Clark Canyon reservoir/dam, 31.5 miles east of Lemhi Pass. Salmon, Idaho, the principal town to the west, is 19 miles northwest of Tendoy; and Dillon, Mont., the principal town to the east, is 18 miles northeast of Clark Canyon Reservoir. The drilling project was proposed by the Department of Energy headquarters personnel in Washington, D.C., during the spring of 1978. The purpose of the project was to demonstrate downward extension of the veins. Drilling was proposed to indicate whether several veins had a depth of 500 feet or more. Little exploration has been carried out on thorium veins. The lack of a ready market for thorium has resulted in little economic incentive for exploration. Most veins in this district are covered by 50 feet of soil.
Hydrogeologic data for selected coal areas, east-central Montana
Hydrogeologic data were collected in selected coal areas of east-central Montana to provide a basis for evaluating the effects of future coal development on the groundwater resources. Inventory records for 916 domestic, stock, public supply, commercial, and test wells are tabulated in the report; the data were collected principally from 1975 through 1976. The locations of the wells are shown on a map at a scale of 1:250,000. Lithologic logs are also included for 149 wells. Chemical analyses of water samples from selected wells consist of 167 samples analyzed for major cations and anions and 24 samples analyzed for miscellaneous constituents.
Limnological data for 12 reservoirs in Valley County, Montana
Water samples were collected from 12 reservoirs in northeastern Montana during the late winter, spring, summer, and early fall of 1978. The resulting physical and chemical water-quality data will be useful in managing the reservoirs for use of stock watering, waterfowl propagation, fish production, and recreation. The surface areas of the reservoirs range for 0.4 to 28.1 hectares with water depths ranging from 0.25 to 6.9 meters. The chemical composition of water varied among reservoirs and with season. Specific conductance ranged from 446 to 4,020 micromhos per centimeter during the winter sampling period and from 62 to 999 micromhos per centimeter during the spring sampling period. Although a pH of 6.9 was measured at one reservoir during the winter, pH values generally ranged from 7.7 to 9.8. Under ice cover, which averaged 1.0 meter thick in late February, three reservoirs attained dissolved-oxygen concentrations above saturation. Each reservoir can be classified as having one of the following three water types: sodium bicarbonate, sodium sulfate, or calcium sodium bicarbonate.
Principal facts for gravity stations in the proposed Middle Judith Wilderness, Montana
A gravity survey was done in the northeast part of the White Sulphur Springs 1°x2° quadrangle as part of the mineral resource evaluation of the proposed Middle Judith Wilderness (fig. 1).
Leasable mineral and waterpower land classification map of the Butte quadrangle, Montana: Lands withdrawn, classified, and prospectively valuable for leasable minerals; occurrences of other selected minerals; and lands withdrawn or classified for waterpower and reservoir sites
No abstract available.
Leasable mineral and waterpower land classification map of the White Sulphur Springs quadrangle, Montana: Lands withdrawn, classified, and prospectively valuable for leasable minerals; occurrences of other selected minerals; and lands withdrawn or classified for waterpower and reservoir sites
No abstract available.