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Research about South Dakota

Source-linked reports with geographic coverage including South Dakota.

At least 289 records · Page 16Linked to original sources

Acute aspergillosis in mallards at Oahe seep near Pierre, South Dakota

Aspergillosis was diagnosed at the cause of death of 158 mallards (Anas platyrhynchos) in January and February 1985 and 11 mallards in December 1985 near Pierre, SD. Isolation of Aspergillus fumigatus from carcass tissues confirmed the diagnosis. The sex ratio of mallards dead from aspergillosis in January and February 1985 was significantly different from the sex ratio in the local population at that time. The source of the fungus was not determined, but severe weather caused physiologically stressed mallards to feeds on corn stored in open piles on the ground, a likely source of the Aspergillus fungus.

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Limnological and fishery studies on Lake Sharpe, a main-stem Missouri River reservoir

Lake Sharpe, the most recent of six main-stem Missouri River reservoirs to be impounded, began to fill in November 1963 and became fully operational in July 1966. At full pool it is 137 km long, and has a surface area of 22,600 ha and a volume of 2.34 km". It is operated as a flow-through power generation system that reregulates discharges from upstream Lake Oahe. Major changes in the water-management regimen during 1966-75 were increased summer discharges beginning in 1969 and increased peaking operations beginning in 1973. Lake Sharpe had a relatively short aging process because it filled rapidly, the water level remained relatively stable, and the waterexchange rate was high. Consequently, most physical, chemical, and biological characteristics were remarkably uniform during 1966–75. The temperature regimen was largely governed by inflow from Lake Oahe. Although the water mass warmed during summer, thermal stratification was generally transient, limited to the lower reservoir, and more common during periods of relatively low discharge rates in 1966–68 than in later years. Variation in turbidity was striking; the midsection of the reservoir was generally most turbid. Chemical ion composition of the water tended to be uniform; observed differences were localized and associated with tributary inflows. Phytoplankton abundance reached its highest levels during 1970–75. Composition of the zooplankton community changed during 1966–75; the abundance of cyclopoid copepods decreased and that of calanoid copepods and cladocerans increased. Total abundance varied during the 10-year period, but without apparent trend. Variation in abundance appeared to be associated with discharge rate, water temperature, and turbidity. The benthic community in 1967-68 consisted mostly of chironomid larvae, which were uniformly distributed over the length of the reservoir.

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In situ and laboratory geotechnical tests of the Pierre Shale near Hayes, South Dakota — A characterization of engineering behavior

A geotechnical investigation of the Pierre Shale near Hayes, South Dakota, was conducted by the U.S. Geological Survey as a basis for evaluating problems in deep excavations into that formation. The physical and mechanical properties of the shale were determined through use of core holes drilled to a maximum depth of 184 m. In situ borehole determinations included a gravimeter survey, pressuremeter testing, thermal profile measurements, and borehole velocity measurements. Onsite and offsite laboratory measurements included rebound measurements, sonic velocity measurements of shear and primary waves, X-ray mineralogy and major element determinations, size analyses, fracture analyses, fabric analyses, and determination of thermal properties.Below 15–22 m, the shale is an unweathered, saturated, overconsolidated, underpressured clay shale with a clay-mineral content ranging between 50 and 100%, dominantly composed of mixed-layer illitic smectites. The physical and mechanical properties vary widely. The variation is related to the clay mineral content (especially in bentonite zones), a large transverse mechanical anisotropy, and zones of fractures and microfractures, which may result from rebound caused by erosion. These may contribute to slope instability over large areas. The thermal and mechanical properties change markedly if the shale is permitted to dry out. The state of stress and overconsolidation appear to be functions of the depositional and erosional history of the deposit. Both are markedly affected by the large fracture zones. The properties of the clay shale indicate problems that may be encountered in excavation and use of deep underground facilities. Key words : anisotropy, characterization, clay shale, consolidation state, physical properties, rebound, relaxation, stress state, thermal properties.

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Hydrogeochemistry of sulfide and arsenic-rich tailings and alluvium along Whitewood Creek, South Dakota (Part 1 of 3 parts)

During 100 years prior to 1977, Whitewood Creek, SD, received about 1 billion tons of arsenic-rich and sulfide-mineral rich tailings from gold mining operations. A hydrogeochemical investigation conducted in 1983-84 focused on four local study areas on the flood plain where tailings deposits exist on top of moderately permeable alluvium. Piezometers in the alluvium beneath the tailings commonly show As at concentrations near or above the Primary Drinking Water Limit of 0.05 mg/l. Water supply wells on the flood plain are situated in alluvium in areas away from tailings where As levels in groundwater are below this limit. In these wells, selenium levels are generally above the limit of 0.01 mg/l. Suggested remedial measures and the likely persistence of these contaminants are discussed.

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Change detection in rangeland environments using Landsat MSS data: A quantitative approach

A range forage utilization study on the Crow Creek Indian Reservation in central South Dakota provided the opportunity to use Landsat multispectral scanner (MSS) data for examining range condition trends. A procedure was developed to compare change in spectral reflectance over time for polygon areas, defined by resource type within management units. A t-test was used to evaluate changes in brightness and greenness within pastures between September 27, 1978, and September 18, 1983. The first principal component transformation from four-band MSS images for both dates was used as a measure of brightness. Greenness was measure using the second principal component transformation for both dates. Examination of the brightness date showed that the assumptions required for a valid t-test were met. The greenness data violated the assumption of independence between dates and was not used for trend comparisons. The t-values calculated from each polygon were coded into three groups: (1) those indicating significant brightness decrease, (2) those indicating significant brightness increase, and (3) those indicating no significant brightness change. Significance was determine at the 5-percent level. These results were formatted into an image, which is a preliminary product for evaluating range condition trends over a 5-year period.

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Early Tertiary age of pitchstone in the northern Black Hills, South Dakota

A block of pitchstone in the northern Black Hills, South Dakota, is Paleocene in age, according to potassium-argon dating of biotite and fission-track dating of zircon in the sample. These data invalidate published suggestions that the age is much younger. The pitchstone is not extrusive in its present position but instead is in a volcanic pipe with other fragments that came downward from as much as 1100 meters above the modern surface.

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Water resources of Hanson and Davison Counties, South Dakota

Five glacial and four bedrock aquifers were delineated in Hanson and Davison Counties. The glacial aquifers, outwash deposits confined by as much as 275 feet of glacial till, are the Floyd, Plum Creek, Ethan, Warren, and Alexandria. The bedrock aquifers are the Niobrara, Codell, Dakota, and Sioux Quartzite Wash, and may be as much as 80, 350, 700, and 500 feet below land surface, respectively. The glacial aquifers averaged 13 to 40 feet in thickness and contain about 670,000 acre-feet of water in storage. Recharge to the Floyd and Plum Creek aquifers is from the Sioux Quartzite Wash aquifer and from fractures in the Sioux Quartzite. Recharge to the Ethan and Warren aquifers is from the Niobrara aquifer. Reported yield to wells from the Floyd and Plum Creek aquifers was as much as 1,000 gallons per minute. Predominant chemical constituents in water from the glacial aquifers are sulfate, calcium, and sodium. The bedrock aquifers averaged 40 to 110 feet in the thickness and contain about 11.3 million acre-feet of water in storage. The direction of water movement in the aquifers is to the northeast. The average reported yield from wells in the bedrock aquifers ranged from 1 to 75 gallons per minute. Reported yield from wells in the Niobrara aquifer was as much as 1,000 gallons per minute. Predominant chemical constituents in water from the Niobrara and Codell aquifers were sulfate, sodium, and calcium. Predominant chemical constituents in water from the Dakota and Sioux Quartzite wash were sulfate and calcium.

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