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Search indexed USGS publications on groundwater, aquifers, geologic maps, mineral resources and earthquakes. Explore source records by subject and place.

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At least 1,405 records · Page 78Linked to original sources
USGS1984

Geology, altitude, and depth of the bedrock surface; altitude of the water table in 1980; and saturated thickness of the Ogallala aquifer in 1980 in the southern High Plains of Colorado

The southern High Plains of Colorado, an area of about 2,800 square miles in the southeastern part of the state, is underlain by the Ogallala Formation of late Tertiary age, The southern High Plains of Colorado extend from the Colorado State line on the east and the ans south to the edge of the Ogallala Formation on the north and west. The Ogallala Formation is an unconsolidated or partly consolidated seposit of sand, gravel, clay silt, and caliche.

Colorado↗
USGS1986

Hydrogeologic framework and properties of regional aquifers in the Hollandale Embayment, southeastern Minnesota

In 1977, the U.S. Geological Survey began a series of investigations of regional aquifer systems in the United States. These studies will provide quantitative information for use in developing and managing regional ground-water supplies. One of these studies, the Northern Midwest Regional Aquifer-System Analysis (RASA) project, concerns the Cambrian and Ordovician age aquifers that occur in southeastern Minnesota and in parts of five other states: Illinois, Indiana, Iowa, Missouri, and Wisconsin (Steinhilber and Young, 1979). This report describes the hydrogeologic framework and properties of the regional aquifers in the Hollandale embayment in southeastern Minnesota (fig. 1). Two other reports describing different aspects of the regional aquifers in southeastern Minnesota were also prepared. Delin and Woodward (1984) mapped the potentiometric surface of each regional aquifer, and described the regional flow regimes; and Woodward (1985) presented a summary of 100 years of water use in southeastern Minnesota based upon trends in municipal-well installations and aquifer utilization.

Minnesota↗
USGS1986

Hydrologic characteristics of soils in parts of Arkansas, Colorado, Kansas, Missouri, Nebraska, New Mexico, Oklahoma, South Dakota, and Texas

Certain physical characteristics of soils, including permeability, available water capacity, thickness, and topographic position, have a definite effect on the hydrology of an area. They control the rate at which precipitation infiltrates or is transmitted through the soil, and thus they have a significant role in determining the rates both of ground-water recharge and surface runoff. In studies of ground-water hydrology, it commonly is useful to differentiate soils areally according to their physical characteristics and to assign values indicating the hydrologic responses of soils in the different areas. In 1980 the U.S. Geologic Surey began a study termed the “Central Midwest Region Aquifer System Analysis,” Jorgensen and Signor, 1981). The regional aquifer system is defined as including all aquifers of Cretaceous age or older in all or parts of nine States included in this report. For part of this analysis, use of a soil-moisture model is planned to obtain estimates of actual evapotranspiraion and recharge to the regional aquifer system. Data for the hydrologic characteristics of the soils in the study area are required as input to this soil-moisture model.

Arkansas, Colorado, Kansas, Missouri, Nebraska, Ne↗