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F. A. Swenson

Publications and source records attributed to F. A. Swenson.

9 recordsLinked to original sources
USGS1968

New theory of recharge to the artesian basin of the Dakotas

The artesian basin of the Dakotas has been studied for many years. The widely held concept has been that recharge enters the equivalents of the Dakota Sandstone, where they are exposed on the flanks of the Black Hills, and moves through this formation to the area of maximum development of the aquifer in eastern North Dakota and South Dakota . Some anomalies, difficult to explain by this concept, have remained unresolved. According to the theory here proposed, recharge enters the Lower Mississippian Pahasapa Limestone and the underlying Englewood Formation where they are exposed on the flanks of the Black Hills. The Pahasapa is in part the equivalent of the Lower and Upper Mississippian Madison Group. The limestones are very cavernous where exposed on the flanks of the Black Hills, and seemingly in the subsurface as well. Streams flowing east from the Precambrian core of the Hills lose virtually all their flow in crossing the cavernous limestones. Widespread karst topography was developed on the Madison during the erosion period which preceded deposition of the Pennsylvanian and Permian Minnelusa Formation. Water moves freely through the cavernous limestone with little head loss for more than 100 miles east of the Black Hills. Pre- Dakota erosion beveled all older rock units and removed many of the intervening beds younger than the Madison. Oil tests indicate that less than 200 feet of strata separate the Madison and Dakota in northern South Dakota east of the Missouri River; this is in marked contrast to the 1800 feet of intervening beds near Rapid City. It is believed that in a zone east of the Missouri River in northern South Dakota and adjacent North Dakota , water which has moved through the limestone more than 150 miles from the Black Hills moves upward into the basal part of the Dakota Sandstone. Much of the water developed in the area of major water use from the Dakota Sandstone has moved a relatively short distance through this formation. The chemical character and artesian pressure of water in the Dakota are influenced significantly by recharge from the Madison Group. West of the zone of recharge the water is highly mineralized and largely of a sodium chloride type. Along the zone of recharge and toward the southeast corner of South Dakota , an area of natural discharge, the water generally is of the calcium sulfate type. North of the Precambrian Sioux Quartzite and east of the calcium sulfate water is an area which has sodium sulfate water. It is inferred that this change results from natural base-exchange softening of the calcium sulfate water as it moves eastward through the Dakota Sandstone.

North Dakota, South Dakota↗
USGS1960

Geology and ground-water resources of the lower Little Bighorn River Valley, Big Horn County, Montana, with special reference to the drainage of waterlogged lands

The lower Little Bighorn River valley, Montana, is in the unglaciated part of the Missouri Plateau section of the Great Plains physiographic province. The river and its principal tributaries rise in the Bighorn Mountains, and the confluence of this northward-flowing stream with the Bighorn River is near the east edge of Hardin, Mont. The normal annual precipitation ranges from about 12 inches in the northern part of the area to 15 inches in the southern part. The economy of the area is founded principally on farming, much of the low-lying land adjacent to the river being irrigated. The irrigated land is within the Crow Indian Reservation, although a part is privately owned. The bedrock formations exposed in the area are of Cretaceous age and include the Parkman sandstone, Claggett shale, Eagle sandstone, Telegraph Creek shale, and Cody shale. The Cloverly formation, Tensleep sandstone, and Madison limestone, which underlie but are not exposed in the area, and the Parkman sandstone in the southern half of the area appear to be the principal bedrock aquifers. All except the Parkman lie at depths ranging from a few feet to several thousand feet, and all appear to be capable of yielding water in commercial quantities. Some of the other formations arc capable of yielding enough water for domestic and stock needs. The river alluvium of Recent age and the Pleistocene terrace deposits are the principal unconsolidated formations in the area with respect to water supply and drainage. Wells yielding as much as 100 gallons per minute may be developed in favorable areas. Pumping tests reveal that the transmissibility of the coarser unconsolidated materials probably ranges from about 15,000 to 30,000 gallons per day per foot. Two tests of the Parkman sandstone showed transmissibilities of 6,000 and 20,000 gallons per day per foot. Although a test of the Cloverly formation showed a transmissibility of only 3,000 gallons per day per foot, the high artesian pressure--80 pounds per square inch at the land surface--in the Cloverly caused the tested well to yield about 200 gallons per minute by natural flow; this is greater than the yield of any other single well in the area. Textural properties were compared with the hydraulic properties determined by laboratory tests to show the relation between different types of waterbearing materials. Materials classified as heavy soils-normally somewhat dense and impervious-had an average permeability of 7.2 gallons per day per square foot, which was more than expected. One sample of very coarse alluvial material had a permeability of 6,000 gallons per day per square foot. The depth to water beneath irrigation units was mapped, thus showing the waterlogged areas. Waterlogging is not a serious problem where the water table is more than 6 feet below the land surface. For the drainage studies the unconsolidated deposits are classified in two zones-coarse-grained sediments resting on the relatively impermeable bedrock floor and overlying fine-grained sediments which extend to the land surface. The transmissibility of the coarse-sediment zone generally is many times greater than that of the fine-sediment zone. Because in many places drains could not be economically dug deep enough to enter the coarse zone, the study of the effectiveness of drainage completed in the fine zone received much attention. The studies showed that, despite a considerable thickness of fine-grained sediments between the bottom of the drain and the top of the coarse zone, drainage ditches frequently were effective in relieving waterlogging of fields nearby. Pilot relief wells installed in existing drains showed that the effectiveness of some drains could be increased appreciably by installing a series of relief wells. Records of fluctuations of water levels in 196 observation wells and water-level contour maps were studied to show the principal areas of recharge and discharge in the irrigable areas.

Montana↗
USGS1955

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.

Montana↗
USGS1948

Geology and ground-water resources of Iwo Jima

Iwo Jima, in the western Pacific Ocean, consists of Motoyama, a broad volcanic cone, at the north, and Mt. Suribachi at the south, with an undulating isthmus between. Motoyama is largely light-gray-buff tuff. A thick andesitic lava flow under Suribachi, exposed in several places, is overlain by a thick deposit of cinder and scoria. The isthmus (called Tidorigahara by the Japanese) is underlain by more than 200 feet of loose black volcanic ash and fine cinder derived from Suribachi. Several small coral reefs are located about 340 and 110 feet above present sea level. Iwo Jima first came into existence, probably early in Pleistocene time, with the building above sea level of the tuff cone of Motoyama. Quite late in the active life of Motoyama, volcanic activity on the southwestern flank resulted in the formation of Suribachi. This activity may have started with the welling up of the andesitic lava which underlies Suribachi. Following the major eruption of Suribachi, relative sea level changed, and the sea stood about 360 feet higher than at present. The broad cone of Motoyama was beveled; the relative sea level then dropped 240 feet, with minor halts to about 120 feet above present level. As the island rose, Suribachi burst forth in its last stage of explosive activity. Wave erosion cut deeply into the andesite flow of Suribachi, and a prominent bench level was formed 120 feet above present sea level. The Japanese on the island were often faced with serious water shortages. Americans drilled wells and obtained moderately large supplies of usable water. The temperature of the water ranges from 105° to 179° F., and the water is somewhat mineralized. The most favorable area for ground-water development is the isthmus.

Iwo Jima↗