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Research about Montana

Source-linked reports with geographic coverage including Montana.

At least 667 records · Page 37Linked to original sources
USGS1983

Potential effects of surface coal mining on the hydrology of the Greenleaf-Miller area, Ashland coal field, southeastern Montana

The Greenleaf-Miller area of the Ashland coal field contains reserves of Federal coal that have been identified for potential lease sale. A hydrologic study was conducted in the potential lease area in 1981 to describe the existing hydrologic system and to assess potential impacts of surface coal mining on local water resources. The hydrologic data collected from wells, test holes, and springs were used to identify aquifers in the alluvium (Pleistocene and Holocene age) and the Tongue River member of the Fort Union Formation (Paleocene age). Coal, clinker, and sandstone beds comprise the aquifers in the Tongue River Member. Most streams are ephemeral and flow only as a result of precipitation. The only perennial surface-water flow in the study area is along short reaches downstream from springs. A mine plan for the area is not available; thus, the location of mine cuts, direction and rate of the mine expansion, and duration of mining are unknown. The mining of the Sawyer and Knoblock coal beds in the Tonge River Member would effect ground-water flow in the area. Declines in the potentiometric surface would be caused by dewatering where the mine pits intersect the water table. Wells and springs would be removed in the mine area; however, deeper aquifers are available as replacement sources of water. The chemical quality of the ground water would change after moving through the spoils. The change would be an increase in the concentration of dissolved solids. (USGS)

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USGS1983

Significance of water quality to fish propagation, waterfowl habitat, livestock watering, and recreation use for 24 lakes and reservoirs in Valley and Phillips Counties, Montana

Twenty-four reservoirs were sampled for water quality to determine their suitability for fish propagation, waterfowl habitat, livestock watering, and recreation. Reservoir-surface areas ranged from 0.2 to 146 hectares and depths ranged from 0.01 to 6.0 meters. Of the reservoirs studied, six generally had water quality that would not be detrimental to fish propagation. Most of the reservoirs were enriched with nutrients and supported large concentrations of phytoplankton and dense growth of aquatic plants. In late winter and late summer, enrichment of shallow reservoirs often resulted in dissolved-oxygen concentrations less than 5.0 milligrams per liter, which is detrimental to fish. Three reservoirs lacked aquatic plants for water fowl habitat. Four reservoirs had small dissolved-oxygen concentration in the bottom water that might be critical to the protection of waterfowl if botulism were to occur. Specific conductance of water samples from three reservoirs was sufficiently close to the criterion of 4,800 microsiemens per centimeter at 25 degrees celsius to be regarded as potentially hazardous to livestock. However, most of the reservoirs generally would not be conducive to recreational swimming. Visibility was limited in most of the reservoirs. In addition, leech populations and growth of submersed aquatic plants in most of the reservoirs would be a nuisance to swimmers.

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USGS1982

Geologic and structure map of the Choteau 1° x 2° quadrangle, western Montana: A digital database

The geologic and structure map of Choteau 1 x 2 degree quadrangle (Mudge and others, 1982) was originally converted to a digital format by Jeff Silkwood (U.S. Forest Service and completed by the U.S. Geological Survey staff and contractor at the Spokane Field Office (WA) in 2000 for input into a geographic information system (GIS). The resulting digital geologic map (GIS) database can be queried in many ways to produce a variey of geologic maps. Digital base map data files (topography, roads, towns, rivers and lakes, etc.) are not included: they may be obtained from a variety of commercial and government sources. This database is not meant to be used or displayed at any scale larger than 1:250,000 (e.g. 1:100,000 or 1:24,000. The digital geologic map graphics and plot files (chot250k.gra/.hp/.eps and chot-map.pdf) that are provided in the digital package are representations of the digital database. They are not designed to be cartographic products.

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USGS1982

Seismic reflection study of Flathead Lake, Montana

A seismic reflection survey of Flathead Lake, Montana, was carried out in 1970 to study the geologic structure underlying the lake. Approximately 200 km of track lines were surveyed resulting in about 140 km of useable data (Fig. 1). A one cu. in. air gun was used as the energy source. Navigation was by a series of theodolite sitings of the boat from pairs of shore-based control points.

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USGS1982

Multielement chemical and statistical analyses from a uranium hydrogeochemical and stream-sediment survey in and near the Elkhorn Mountains, Jefferson County, Montana. Part I: Surface water

Fifty-two surface-water samples, collected from an area south of Helena, Jefferson County, were analyzed for 51 chemical species. Of these variables, 35 showed detectable variation over the area, and 29 were utilized in a correlation analysis. Two populations are distinguished in the collected samples and are especially evident in the plot of Ca versus U. Samples separated on the basis of U versus Ca proved to represent drainage areas of two differing lithologies. One group was from waters that drain the Boulder batholith, the other from those that drain the Elkhorn Mountains volcanic rocks. These two groups of samples, in general, proved to have parallel but different linear trends between U and other elements. Therefore, the two groups of samples were treated separately in the statistical analyses. Over the area that drains the Boulder batholith, U concentrations in water ranged from 0.37 to 13.0 μ g/l , with a mean of 1.9 μ g/l. The samples from streams draining volcanic areas ranged from 0.04 to 1.5 μ g/l, with a mean of 0.42 μ g/l. The highest U values (12 and 13 μ g/l) occur along Badger Creek, Rawhide Creek, Little Buffalo Gulch, and an unnamed tributary to Clancy Creek. Conductivity, hardness, Ba, Ca, CI, K, Mg, Na and Sr are significantly correlated with U at or better than the 95 percent confidence limit in both populations. For water draining the Boulder batholith, uranium correlates significantly with akalinity, pH, bicarbonate, Li, Mo, NO2+NO3, P04, SiO2, SO4, F, and inorganic carbon. These correlations are similar to those found in a previous study of water samples in north-central New Mexico (Wenrich-Verbeek, 1977b). Uranium in water from the volcanic terrane does not show correlations with any of the above constituents, but does correlate well with V. This relationship with V is absent within the Boulder batholith samples.

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USGS1982

Multielement chemical and statistical analyses from a uranium hydrogeochemical and stream-sediment survey in and near the Elkhorn Mountains, Jefferson County, Montana: Part II, Stream sediments

Fifty-two stream-sediment samples, collected from an area south of Helena, Jefferson County, Montana, were sieved into two size fractions (<88 ?m, and between 88 and 149 ?m) and analyzed for 80 different chemical species. Of these species, 43 showed detectable variation over the area, 31 were subjected to correlation analysis for the fine size fraction, and 30 for the coarse-size fraction. Two populations distinguished in the surface water samples of this study (Suits and Wenrich, 1981) are not as clearly evident in the stream sediments. However, stream-sediment samples from streams draining the Boulder batholith and from streams draining volcanics and volcanogenic sediments (referred to only as volcanics) do show differences in their geochemical relationships, especially between SiO2, Al203 and Na2O versus U. Thus, the sediments were also treated statistically as two lithologic populations as well as two populations based on size fraction. In the fine fraction samples, U ranged from 1.3 to 78 ppm, averaging 25 ppm for the Boulder batholith samples and 8 ppm for the volcanics samples. The range for the coarse fraction was 1.9 to 55 ppm with an average of 17 for the Boulder batholith group and 7 for the volcanics group. High U values (>50 ppm for the fine fraction) were encountered in samples from the Warm Springs Creek drainage area, along Prickly Pear Creek near Welmer and Golconda Creeks and along Muskrat Creek. All groups showed a significant correlation at the 99 percent confidence level (r between 0.73 and 0.77) between U and Th. Uranium was found to correlate significantly only with Th (as mentioned above) and with -Ni in the fine fraction of the volcanics group. U correlates significantly with -Al2O3, Ba, organic C, -K2O, -Sr and Y in both size fractions for the Boulder batholith. Correlations between U and each of several elements differ for the fine and coarse fractions of the Boulder batholith group, suggesting that the U distribution in these stream sediments is in large part controlled by grain size. Correlations were found between U and CaO, Cr, Fe203, -Na2O, Sc, -SiO2, TiO2, Yb and Zr in the coarse fraction but not in the fine fraction. U correlates weakly (to the 90% confidence level, crc<.37) with -Co and -Cu in the fine but not the coarse fraction. These results are compared to a previous study in the northern Absaroka mountains. Correlation coefficients between all other elements determined from these samples are also shown in Tables 12 to 15.

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USGS1982

Potentiometric-surface map of water in the Judith River Formation in the northern Great Plains area of Montana

The potentiometric surface of the Judith River Formation is mapped at a scale of 1:1,000,000. The map is one of a series produced as part of a regional study of aquifers of Cenozoic and Mesozoic age in the northern Great Plains of Montana. The contour interval is 200 feet. Water in the Judith River Formation occurs under water-table and artesian conditions. The direction of regional ground-water movement is from west to east. Water is discharged from the Judith River Formation to the Milk River from near Havre, Montana, to Malta and to the Missouri River south of the Bearpaw and Little Rocky Mountains. The average discharge from 236 wells is about 10 gallons per minute, and the specific capacity of 186 wells averages 0.66 gallon per minute per foot of drawdown.

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USGS1982

Potentiometric-surface map of water in the Lakota Formation and equivalent units in the northern Great Plains area of Montana

The potentiometric surface of water in the lower Cretaceous Lakota Formation and equivalent units (Cut Bank Sandstone Member , Sunburst Sandstone Member, and Moulton Member of Kootenai formation; Third Cat Creek sandstone of Kootenai Formation; Pryor Conglomerate Member of Kootenai Formation) is shown on a base at a scale of 1:1,000,000. The map is one of a series produced as part of a regional study of aquifers of Cenozoic and Mesozoic age in the northern Great Plains of Montana. The contour interval is 200 feet. Water in the Lakota Formation and equivalent units occurs under water-table and artesian conditions. The direction of regional groundwater movement is east and north from the recharge areas in the Little Belt and Big Snowy Mountains. The average discharge from 20 wells is about 29 gallons per minute and the specific capacity of 18 wells averages 0.75 gallon per minute per foot of drawdown.

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USGS1982

Potentiometric-surface map of water in the Fox Hills-Lower Hell Creek aquifer in the Northern Great Plains area of Montana

The potentiometric surface of water in the Upper Cretaceous Fox Hills-lower Hell Creek aquifer is shown on a base map at a scale of 1:1,000,000. The map is one of a series produced as part of regional study of aquifers of Cenozoic and Mesozoic age in the northern Great Plains of Montana. The contour interval is 100 feet. The map shows that the direction of regional ground-water movement is toward the northeast. Recharge occurs on the flanks of the Black Hills uplift, the Cedar Creek anticline, the southwest part of the Bull Mountains basin, and on the out-crop areas. Discharge from the aquifer occurs along a short reach of the Yellowstone River. The average discharge from 335 wells is about 16 gallons per minute and the specific capacity of 185 wells averages 0.49 gallon per minute per foot of drawdown. (USGS)

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USGS1982

Potentiometric-surface map of water in the Eagle Sandstone and equivalent units in the northern Great Plains area of Montana

The potentiometric surface of water in the Upper Cretaceous Eagle Sandstone and equivalent units (Virgelle Sandstone and Telegraph Creek Formation) is shown on a base map at a scale of 1:1,000,000. The map is one of a series of maps produced as part of a regional study of aquifers of Cenozoic and Mesozoic age in the northern Great plains of Montana. The contour interval is 200 feet. The map shows that the directions of regional ground-water movement is from west to east except in the extreme northwestern corner where the movement is from east to west. Water is discharged from the Eagle Sandstone to the Missouri River south of the Bearpaw Mountains. In the area north of the Bearpaw Mountains, depressurization from gas production may account for the decline in the potentiometric surface. The average discharge from 115 wells is about 23 gallons per minute and the specific capacity of 85 wells averages 1.4 gallons per minute per foot of drawdown.

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USGS1982

Hydrology of the Prairie Dog Creek drainage basin, Rosebud and Big Horn Counties, Montana

The Prairie Dog Creek drainage basin in southeastern Montana was in vestigated during 1978-79 to assess the surface-water and ground-water resources and the quality of water in an area having coal-mining potential. The area, a 24.2 - square - mile basin, is located 30 miles southwest of Ash- land, Montana. The principal mineable coal is the 40-to 60-foot-thick Wall and lower Wall coal beds near the middle part of the Tongue River Member of the Fort Union Formation (Paleocene age). Other possibly mineable intervals are the Canyon coal bed lying 200 to 250 feet above the Wall, and the Brews ter-Arnold coal bed lying about 220 feet below the base of the Wall coal beds. The hydrologic regime in the basin is composed of Prairie Dog Creek and sandstone, coal, clinker, and alluvium aquifers. Prairie Dog Creek, which originates from springs and seeps issuing from coal and sandstone layers, maintained perennial flow in its upstream and middle reaches during 1978 and 1979. In its downstream reach, the flow decreased consistently until the channel near the mouth had only standing water or was dry. The dissolved-solids concentration of streamflow during periods of high flow (1 cubic foot per second or more) in the spring months ranged from 700 to about 1,000 milligrams per liter and during periods of lesser flow (0.5 cubic foot per second or less) in the summer ranged from about 1,300 to 1,600 milligrams per liter. Forty-two cased observation wells were used to obtain data on aquifer characteristics and quality of water. Relatively clean (free of silt or mud) sandstone beds have transmissivities of about 15 feet squared per day; the water was a magnesium sulfate or sodium sulfate type and dissolved- solids concentrations ranged from about 2,170 to 3,260 milligrams per liter. The Wall coal aquifer has transmissivities ranging from 2.5 to 65 feet squared per day; the water was a sodium sulfate type and dissolved-solids concentrations ranged from 1,820 to 4,190 milligrams per liter. The Brewster-Arnold coal aquifer has transmissivities similar to those of the Wall coal but the water was a sodium bicarbonate type; the water contained an excessive concentration of fluoride (more than 10 milligrams per liter) and had a very high sodium - adsorption ratio (more than 60). The alluvial aquifer in the Prairie Dog Creek valley has transmissivities ranging from about 1,000 to 5,000 feet squared per day in the middle reaches and as much as 9,200 feet squared per day near the mouth of the creek. The water quality changed from a magnesium sulfate type in the middle reaches to a sodium sulfate type near the mouth. The dissolved-solids concentration decreased from about 1,700 milligrams per liter in the middle reaches to about 1,100 milligrams per liter near the mouth as inflow of water from clinker and alluvial deposits beneath terraces diluted the alluvial water.

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USGS1982

Streamflow characteristics of the upper Columbia River basin, Montana, through 1979

Statistical summaries of streamflow data for selected stream-gaging sites presented in this report aid in appraising the hydrology of the upper Columbia River basin in Montana. Streamflow records are provided for 54 gaging stations for the period of record. Streamflow records for five gaging stations were compiled into separate periods related to changes in regulation after data collection commenced. The entire period of record, the period before regulation, and the period after regulation are presented for comparison. For each gaging station selected for this report, a brief description is given for station location, drainage area, period of record, revisions of previously published records, type and history of gages, regulation and diversions, and extremes of discharge. These data are followed by tables of monthly and annual flow statistics, flood-frequency data, low-flow and high-flow frequency data, and flow-duration information. (USGS)

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USGS1982

Quality of streams in the Bull Mountains region, south-central Montana

In October 1977, water-quality monitoring stations were established on five small streams that drain the Bull Mountains and also on the Musselshell River to document present water-quality conditions in a coal area of south-central Montana. Relatively static water-quality conditions exist throughout the annual flow cycle on the small streams but water quality varies with time on the Musselshell River. The near absence of surface runoff in the Bull Mountains during the study and the dominance by the base-flow component account for stability of water quality in the small streams. High-mountain runoff coupled with storms and prairie runoff impact the base flow of the Musselshell River. Bicarbonate and sulfate were the principal anions and are present in nearly equal proportions in all small streams. Except for West Parrot Creek, magnesium was the most dominant cation. West Parrot Creek, which consistently contained the smallest levels of dissolved solids, had sodium rather than magnesium as the principal cation. Fattig Creek was highest in dissolved solids with an approximate concentration range of 900 to 2,100 milligrams per liter. Suspended-sediment discharge in the streams was relatively small; no stream exceeded 0.32 ton per day. The Musselshell River had dissolved solids concentrations that ranged from about 450 milligrams per liter during spring runoff to 1,800 milligrams per liter during periods of base flow. The sodium sulfate-type water, which is common during base flow, is diluted during runoff with water having principal ions of calcium, magnesium, and bicarbonate. Suspended-sediment loads ranged from 0.56 to 37,300 tons per day and correlated directly to stream discharge. (USGS)

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