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Background: A sequence of gently dipping carbonate bedrock - the Bertie Formation, Akron Dolostone, and Onondaga Limestone crop out along a 2- to5-mile wide band in western and central New York. These bedrock units trend east-west for 250 miles across the State and form extensive carbonate-bedrock aquifers which transmit and yield water from solution-enlarged fractures, bedding planes, and other openings (Olcott, 1995). Bedding planes or sub-horizontal fractures typically are the most enlarged and important water conduits. Karstic features such as sinkholes, swallets, solution channels, and caverns can locally transmit large amounts of surface water into the ground where the groundwater can move quickly and over...
Categories: Data,
Project;
Types: Downloadable,
Map Service,
OGC WFS Layer,
OGC WMS Layer,
Shapefile;
Tags: Aquifer Mapping,
Aquifer Mapping,
Aquifer Mapping,
Basin & Hydrogeologic Characterization,
Basin & Hydrogeologic Characterization,
This dataset captures in digital form the results of previously published U.S. Geological Survey (USGS) Water Mission Area studies related to water resource assessment of Cenozoic strata and unconsolidated deposits within the Mississippi Embayment and the Gulf Coastal Plain of the south-central United States. The data are from reports published from the late 1980s to the mid-1990s by the Gulf Coast Regional Aquifer-System Analysis (RASA) studies and in 2008 by the Mississippi Embayment Regional Aquifer Study (MERAS). These studies, and the data presented here, describe the geologic and hydrogeologic units of the Mississippi embayment, Texas coastal uplands, and the coastal lowlands aquifer systems, south-central...
The article describes the hydrogeological problems related to water influx to the mine and water sulphate content association with underground oil shale mining in an environmentally sensitive area of Estonia. The water balance method was used to calculate the ratio of mine water outflow/inflow. Water balance calculations are needed for estimating the groundwater transversal flow into closed mines. Before oil shale mining groundwater geochemical processes are characterised by low sulphate content. Dewatering of oil shale mines lowered groundwater level in the Keila?Kukruse aquifer, and caused an about 50-fold increase in sulphate by intensive oxidation of pyrite of natural origin. The mobile sulphate ion may serve...
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...
Cumulatively, headwater streams contribute to maintaining hydrologic connectivity and ecosystem integrity at regional scales. Hydrologic connectivity is the water-mediated transport of matter, energy and organisms within or between elements of the hydrologic cycle. Headwater streams compose over two-thirds of total stream length in a typical river drainage and directly connect the upland and riparian landscape to the rest of the stream ecosystem. Altering headwater streams, e.g., by channelization, diversion through pipes, impoundment and burial, modifies fluxes between uplands and downstream river segments and eliminates distinctive habitats. The large-scale ecological effects of altering headwaters are amplified...
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...
This digital dataset was created as part of a U.S. Geological Survey hydrologic resource assessment and development of an integrated numerical hydrologic model of the hydrologic system of the Upper Colorado River Basin, an extensive region covering approximately 412,000 square kilometers in five states: Wyoming, Colorado, Utah, Arizona, and New Mexico. As part of this larger study, the USGS developed this digital dataset of geologic data and a three-dimensional hydrogeologic framework model (3D HFM) that define the elevation, thickness, and extent of seven hydrogeologic units in the Upper Colorado River Basin. The hydrogeologic setting of the Colorado Plateau consists of thick Paleozoic, Mesozoic, and Cenozoic aquifers,...
This dataset captures in digital form previously published maps showing the inferred extent and subsurface elevation of several Paleozoic consolidated rock units in the northern Midwest of the United States. Data released here were published as figures within a U.S. Geological Survey (USGS) Water Mission Area report documenting results from a study of the regional hydrogeology and ground-water quality of the Cambrian-Ordovician aquifer system in the northern Midwest. This study was part of the USGS national Regional Aquifer-System Analysis (RASA) Program. Sandstone and carbonate rocks of Cambrian and Ordovician age compose much of the sedimentary rocks overlying the Precambrian basement in the northern Midwest and...
Cumulatively, headwater streams contribute to maintaining hydrologic connectivity and ecosystem integrity at regional scales. Hydrologic connectivity is the water-mediated transport of matter, energy and organisms within or between elements of the hydrologic cycle. Headwater streams compose over two-thirds of total stream length in a typical river drainage and directly connect the upland and riparian landscape to the rest of the stream ecosystem. Altering headwater streams, e.g., by channelization, diversion through pipes, impoundment and burial, modifies fluxes between uplands and downstream river segments and eliminates distinctive habitats. The large-scale ecological effects of altering headwaters are amplified...
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