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C. A. Armstrong

Publications and source records attributed to C. A. Armstrong.

9 recordsLinked to original sources
USGS1985

The geohydrologic system and probable effects of mining in the Sand Creek-Hanks lignite area, western Williams County, North Dakota

The investigation was undertaken to define the geohydrology of the Sand Creek-Hanks area and to project probable hydrologic effects of lignite mining on the area. Aquifers occur in sandstone beds in the Fox Hills Sandstone and the Hell Creek Formation of Cretaceous age and in sandstone lenses and lignite beds in the Tongue River and Sentinel Butte Members of the Fort Union Formation of Tertiary age. The top of the Fox Hills aquifer ranges from about 1,200 to 2,000 feet below land surface. Yields of wells completed in the aquifer could be as much as 60 gallons per minute. Water in the Fox Hills aquifer is a sodium bicarbonate type and generally Depths to the top of the Hell Creek aquifer range from about 900 to 1,600 feet. Well yields range from less than 10 to 40 gallons per minute. Water in the aquifer is a sodium bicarbonate type and generally contains between 1,000 and 2,200 milligrams per liter dissolved solids. Depths to aquifers in the Tongue River and Sentinel Butte Members of Fort Union Formation range from near land surface to about 1,000 feet below land surface. Wells completed in the aquifers may yield as much as 40 gallons per minute of sodium bicarbonate or a sodium sulfate type water that contains about 800 to 4,100 milligrams per liter dissolved solids. Glacial drift covers most of the study area. The drift thickness ranges from a veneer to about 380 feet. Well yields range from a few gallons per minute to 900 gallons per minute. Dissolved-solids concentrations in water from the glacial drift generally range from 477 to 2,050 milligrams per liter. Mining of lignite will destroy all aquifers in and above the mined lignite and will expose overburden to oxidation. Leaching will cause an increase in dissolved solids in ground water immediately beneath the mines and possibly will cause some increase in the dissolved solids in low flows in area streams.

North Dakota↗
USGS1985

A preliminary assessment of land-surface subsidence in the El Paso area, Texas

The northeast and southeast parts of the El Paso area are underlain by Hueco bolson deposits as much as 9,000 feet thick. The deposits consist of lenses of gravel, sand, silt, and clay. In the Rio Grande Valley, about 400 to 450 feet of these deposits have been eroded and replaced with as much as 200 feet of alluvium. Ground water in the shallow alluvial aquifer in the Rio Grande Valley and in the Hueco bolson aquifer outside the valley is under water-table conditions, whereas ground water in the bolson aquifer in the valley is under leaky artesian conditions. Maximum water-level declines in the Hueco bolson aquifer are 110 feet east of the Franklin Mountains and 150 feet in the downtown El Paso area. For the shallow aquifer, the maximum declines have been 125 feet in the downtown area. Compressable materials in the freshwater zone of the aquifer range from 50 to 450 feet. Recharge from the Rio Grande to the shallow alluvial aquifer has increased from an estimated 15,000 acre-feet during 1968 to 30,000 acre-feet during 1983, an increase of about 1,000 acre-feet per year. Leakage from the Rio Grande is expected to continually increase in the near future because of a continued decline in ground-water levels. The amount of leakages from the canals is much less than from the river. Releveling of bench marks along lines to the northeast and the southeast of the Rio Grande, and along its channel commonly show land subsidence of about 0.2 foot. The maximum measured subsidence is 0.41 foot along the river in the Chamizal zone. No subsidence was detected at the Riverside Diversion Dam. A comparison of subsidence, water-level declines, and clay thickness along the three survey lines shows the expected correlation of greater subsidence with thicker accumulated clay material for a given decline in water levels. The preconsolidation stress was expected to range from 85 to 115 feet of water-level decline on the basis of subsidence studies in Arizona and California. A study of specific-unit compaction along the three survey lines shows that the values usually range between 1.0 to 2.5 x 10-5 feet per feet squared. These values are comparable to the ones computed in the Tulare-Wasco, California, and Houston-Galveston, Texas, areas following the exceedance of the local preconsolidation stress. Because of this comparability, the specific-unit compaction for future periods in the El Paso area probably will not increase dramatically when the preconsolidation stress is exceeded, if it has not already been exceeded. In addition to regional subsidence, local subsidence is indicated by observable surface fractures but has not been verified by precise leveling. These local areas coincide with areas that historically were swamps along the Rio Grande.

Texas↗
USGS1984

Evaluation of the hydrologic system and potential effects of mining in the Dickinson lignite area, eastern slope and western Stark and Hettinger counties, North Dakota

The investigation of the water resources of the Dickinson lignite area, an area of about 500 square miles, was undertaken to define the hydrologic system of the area and to project probable effects of coal mining on the system. Aquifers occur in sandstone beds in: the Fox Hills Sandstone and the lower Hell Creek Formation of Cretaceous age, the upper Hell Creek Formation of Cretaceous age and the lower Ludlow Member of the Fort Union Formation of Tertiary age, and the upper Ludlow and lower Tongue River Members of the Fort Union Formation of Tertiary age. Aquifers also occur in the sandstone and lignite lenses in the upper Tongue River Member and the Sentinel Butte Member of the Fort Union Formation. Depths to the Fox Hills-lower Hell Creek aquifer system range from about 1,300 to 1,710 feet. Well yields range from 18 to 100 gallons per minute. The water is soft and is a sodium bicarbonate type. Dissolvedsolids concentrations in samples collected from the aquifer system ranged from 1,230 to 1,690 milligrams per liter. Depths to the upper Hell Creek-lower Ludlow aquifer system range from about 720 to 1,040 feet. Well yields generally are less than 30 gallons per minute but may be as much as 150 gallons per minute. The water is soft and a sodium bicarbonate type. Dissolved-solids concentrations in samples collected from the aquifer system ranged from 1,010 to 1,450 milligrams per liter. Depths to the upper Ludlow-lower Tongue River aquifer system range from about 440 to 713 feet. Well yields may range from about 1 to 100 gallons per minute. The water generally is soft and a sodium bicarbonate type but may be moderately hard and a sulfate type in the southwestern part of the area. Dissolved-solids concentrations in samples collected from the aquifer system ranged from 995 to 1,990 milligrams per liter. Depths to the upper Tongue River-Sentinel Butte aquifer system range from near land surface to about 530 feet below land surface. Well yields generally range from about 1 to 185 gallons per minute. Yields from the lignite parts of the system range from about 2 to 60 gallons per minute. The water generally is a sodium bicarbonate type, but locally sulfate is the dominant anion. Dissolved-solids concentrations in samples collected from the aquifer system generally ranged from 574 to 2,720 milligrams per liter.

North Dakota↗
USGS1983

Evaluation of the effects of Lake Audubon on ground- and surface-water levels in the Lake Nettie area, eastern McLean County, North Dakota

Water logging and flooding of some roads and agricultural lands have become a problem in the Lake Nettie area of eastern McLean County. Part of the flooding is caused by the raising of Lake Audubon about 13 feet from an elevation of about 1,835 feet to 1,848 feet and its effect on ground-water levels in the upper unit of the Lake Nettie aquifer by way of leakage from the lower unit. The major part of the flooding is caused by the greater than normal precipitation and the resulting runoff. Recharge to the aquifer is from the direct infiltration of precipitation and snowmelt, the lateral percolation of water from the adjacent Fort Union Formation and glacial-drift aquifers, and from Lake Audubon. Discharge is by evapotranspiration and by ground-water movement into undrained surface-water basins in the Lake Holmes-Lake Williams area and southward through Lake Ordway or westward to Lake Audubon. Trends shown on hydrographs indicate that near equilibrium between recharge and discharge has been reestablished in the lower unit of the Lake Nettie aquifer in the area between Lake Audubon and Lake Nettie, but east of Lake Nettie water levels are still rising. As of 1982, water-level rises caused by the raising of Lake Audubon are as much as 4 feet in the lower unit of the Lake Nettie aquifer and are between 1 and 2 feet in the upper unit of the Lake Nettie aquifer, which is hydraulically connected to Lake Nettie, Crooked Lake, and Slough No. 1. There is a rise in Slough No. 1, about 2 miles east of Lake Audubon, that can be attributed to the higher levels of Lake Audubon. Apparently rises also have occurred in many other sloughs. Water levels have risen in the Turtle Lake aquifer both as a result of raising the water level in Lake Audubon to an elevation of about 1,848 feet and the McClusky Canal to an elevation of about 1,844 feet. Water levels have risen as much as 6 feet near the canal, but generally less than 1 foot at distances of about 0.5 mile.

North Dakota↗
USGS1981

Supplement to predictive modeling of effects of the planned Kindred Lake on ground-water levels and discharge, southeastern North Dakota

A digital model was used to describe a ground-water system in glacial deltaic deposits near Kindred, N.D., and to predict the effects on ground-water levels of a planned lake at the 950-, 960-, 970-, 984-, and 995-foot stages. Model analysis indicates that only the area within a radius of about 2 miles of the dam on the present Sheyenne River would be affected by rising water levels as a result of a lake stage at 995 feet. The rise of water levels depends on time and hydraulic properties of the aquifer. The maximum projected rise in water levels at the various stages should occur in about 50 to 100 years. Evapotranspiration and existing drains will be effective in limiting the extent of water-level rise. (USGS)

Open-File Report↗
USGS1977

Ground-water resources of Griggs and Steele Counties, North Dakota

Griggs and Steele Counties, in east-central North Dakota, are underlain by bedrock of Ordovician, Jurassic, and Cretaceous ages. The Fall River and Lakota Formations of Cretaceous age form the Dakota aquifer. The fractured upper part of the Pierre Formation (shale), also of Cretaceous age, forms another bedrock aquifer. The Dakota aquifer, which consists mainly of interbedded shale and sandstone units, may yield as much as 500 gallons per minute (32 liters per second) of sodium sulfate water to wells at selected locations. The Pierre aquifer yields from 1 to 10 gallons per minute (0.06 to 0.63 liters per second) of sodium bicarbonate or sodium sulfate water to wells. Four major glacial-drift aquifers are present in the study area. The Spiritwood aquifer system may supply as much as 1,500 gallons per minute (95 liters per second) of water to wells. Water samples contained dissolved-solids concentrations ranging from 244 to 9,800 milligrams per liter. The Galesburg aquifer will yield as much as 1,000 gallons per minute (63 liters per second) of water to wells. Water samples contained dissolved-solids concentrations ranging from 317 to 2,170 milligrams per liter. The McVille aquifer will yield as much as 500 gallons per minute (32 liters per second) to wells. Water samples contained dissolved-solids concentrations ranging from 449 to 2,200 milligrams per liter. The Elk Valley aquifer could yield 30 gallons per minute (2 liters per second) to wells. Water samples contained dissolved-solids concentrations ranging from 397 to 2,890 milligrams per liter. Six communities in the project area use ground-water supplies. Rural water districts are being developed in the two-county area that will provide dependable ground-water supplies for many farms and small municipalities. The Spiritwood aquifer system and the McVille and Galesburg aquifers are capable of supplying the water needs of these districts and could also provide water for irrigation.

North Dakota↗
USGS1970

Geology and ground water resources, Williams County, North Dakota

Williams County, in northwestern North Dakota, is located near the center of the structural and sedimentary Williston basin. The preglacial sedimentary formations beneath the county are as much as 14,828 feet thick. Their beds dip generally to the south except along the flanks of the north-south striking Nesson anticline in the eastern part of the county. Late Wisconsinan glacial deposits cover all of Williams County except along the Missouri River and other scattered small areas.

North Dakota↗