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The U.S. Geological Survey (USGS) has been engaged in airborne electromagnetics (AEM) since the 1970s, playing a role in the development of early acquisition systems, developing calibration methods, refining standards for data acquisition, improving data processing, modeling, and interpretation methods, and expanding the range of AEM applications. However, USGS AEM survey visibility and data accessibility has not advanced as rapidly as our use of the technique. This data release catalogs AEM surveys in the United States that have contributed to studies under USGS programs including Water, Geologic Mapping, Minerals, Energy, Environmental Health, Ecosystems, Hazards, and Climate. This dataset contains locations for...
Categories: Data;
Types: ArcGIS REST Map Service,
ArcGIS Service Definition,
Downloadable,
Map Service;
Tags: Alabama,
Arizona,
Arkansas,
California,
Colorado,
More than 11,500 well records, such as geophysical logs, drilling descriptions, and published hydrogeologic framework information, were evaluated to help characterize the framework of hydrogeologic units in and near Gaines, Terry, and Yoakum Counties, Texas. Additional geophysical data were collected to improve the spatial coverage across the study area and to reduce uncertainty with regard to hydrogeologic unit extents. The evaluation of existing data plus the collection of new geophysical data provided that basis for developoing a refined understanding of how the saturated thickness of the Ogallala and Edwards-Trinity aquifers vary throughout the study area.
The transboundary Mesilla Basin/Conejos-Médanos aquifer system was identified as one of the priority transboundary aquifer systems for additional study by the United States and Mexico U.S.-Mexico Transboundary Aquifer Assessment Act of 2006 (United States-Mexico Transboundary Aquifer Act, Public Law 109-448). As one of the largest rechargeable groundwater systems by total available volume in the Rio Grande/Rio Bravo del Norte Basin region of the United States and Mexico, the Mesilla Basin/Conejos-Médanos aquifer system supplies water for irrigation as well as municipal use in El Paso, Texas; Las Cruces, New Mexico; and Ciudad Juárez, Chihuahua, Mexico (Alley, 2013). The U.S. Geological Survey in cooperation with...
Declining groundwater levels in and near Gaines, Yoakum, and Terry Counties in the Texas Panhandle have raised concerns about the amount of available groundwater and the potential for water-quality changes resulting from dewatering and increased vertical groundwater movement between adjacent water-bearing hydrogeologic units. More than 9,800 well records, such as geophysical logs, drilling descriptions, and published hydrogeologic framework information, were evaluated to help characterize the framework of hydrogeologic units in the study area. Additional geophysical data were collected to improve the spatial coverage across the study area and to reduce uncertainty with regard to hydrogeologic unit extents. Of greatest...
The hydrogeology of the Cannon Air Force Base (AFB) in Curry County, is being investigated to better understand the mechanics of groundwater flow in the area, including the identification of preferential groundwater flow paths. Mapping the top of the Dockum Group was done to help identify potential paleochannels that may have eroded the surface of the Dockum Group and subsequently filled in with coarse-grained sediments of the overlying Ogallala Formation. The Dockum Group is composed of sandstone, siltstone, mudstone, and shale that were originally deposited in fluvial and lacustrine environments (McGowen and others, 1979). The upper part of the Dockum Group is a thick layer of red clay referred to locally as the...
Note: this data release is currently being revised and is temporarily unavailable. This data release is a compilation of the locations of airborne geophysical surveys in the United States. The inventory documents public airborne geophysical surveys primarily flown by or contracted by the USGS from 1943 to present. In addition, surveys from the State of Alaska, Department of Natural Resources, Division of Geological and Geophysical Surveys (DGGS): Airborne GeophysWeb, the Bureau of Land Management, the Department of Energy and other state agencies have also been included. The surveys have contributed to studies under USGS programs including Water, Geologic Mapping, Minerals, Energy, Environmental Health, Ecosystems,...
Categories: Data,
Data Release - Under Revision;
Types: ArcGIS REST Map Service,
ArcGIS Service Definition,
Downloadable,
Map Service;
Tags: Alabama,
Alaska,
Arizona,
Arkansas,
California,
Declining groundwater levels in the Hueco Bolson have raised concerns about the amount of available groundwater and the potential for water-quality changes. Fresh groundwater stored in the aquifer is bordered by regions of brackish-to-saline groundwater, and as the water levels in the Hueco Bolson have declined the local and regional hydraulic gradients have been altered such that the brackish-to-saline groundwater regions have encroached upon and degraded the quality of the freshwater zones (Hibbs 1999; Heywood and Yager, 2003). To help delineate the freshwater and saline groundwater transition zone, 20 time-domain electromagnetic soundings were collected to provide resistivity structure data in the area. This...
In cooperation with the Llano Estacado Underground Water Conservation District (LEUWCD), the Sandy Land Underground Water Conservation District (SLUWCD), and the South Plains Underground Water Conservation District (SPUWCD), the U.S. Geological Survey (USGS) compiled historical geophysical and geochemical data in Gaines, Yoakum, and Terry Counties, Texas, and collected additional data where gaps were evident to assist with building a conceptual hydrogeologic model of the Gaines, Yoakum, and Terry Counties region. The compiled historical data includes all data available from predevelopment (pre-1945) through present day. For this study, predevelopment is considered everything prior to 1945 when the large-scale groundwater...
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