This data set represents the extent of the Mississippi embayment aquifer system in the states of Louisiana, Arkansas, Mississippi, Alabama, Tennessee, and Kentucky.

This data set represents the extent of the Floridan aquifer system in the states of Florida, Georgia, and Alabama.

This data set represents the extent of the Valley and Ridge aquifers in the states of New York, New Jersey, Pennsylvania, Maryland, Virginia, West Virginia, Tennesse, Georgia, and Alabama.

This geodatabase includes spatial datasets that represent the Southeastern Coastal Plain aquifer system in the States of Alabama, Georgia, Mississippi, South Carolina, and Tennessee. Included are: (1) polygon extents; datasets that represent the aquifer system extent, the entire extent subdivided into subareas or subunits, and any polygon extents of special interest (outcrop areas, no data available, areas underlying other aquifers, anomalies, for example), (2) raster datasets for the altitude of each aquifer subarea or subunit, (3) altitude, and/or if applicable, thickness contours used to generate the surface rasters, (4) georeferenced images of the figures that were digitized to create the altitude and thickness contours. The images and digitized contours are supplied for reference. The extent of the Southeastern Coastal Plain aquifer system is derived the linework in the Southeastern Coastal Plain aquifer system extent maps in a digital version of the aquifer extent presented in the Groundwater Atlas of the United States (the U.S. Geological Survey Hydrologic Atlas HA-730-F, -730-G, and -730-K. The Southeastern Coastal Plain aquifer system has 4 aquifer subunits, in order from the most surficial to the deepest: A1: Chickasawhay River aquifer, A2: Pearl River Aquifer, A3: Chattahoochee River Aquifer, and A4: Black Warrior River Aquifer. The altitude and thickness contours for each available subunit were digitized from georeferenced figures of altitude contours in U.S. Geological Survey Profession Paper 1410-B, (USGS PP 1410-B), and the resultant top and bottom altitude values were interpolated into surface rasters within a GIS using tools that create hydrologically correct surfaces from contour data, derive the altitude from the thickness (depth from the land surface), and merge the subareas into a single surface. The primary tool was "Topo to Raster" used in ArcGIS, ArcMap, Esri 2014. The surface rasters were corrected for the areas where the altitude of an underlying layer of the aquifer exceeded altitude of an overlying layer.

Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system were developed to define an updated hydrogeologic framework as part of the U.S. Geological Survey Groundwater Resources Program. This feature class contains the first magnitude springs of the first magnitude springsheds.

Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system were developed to define an updated hydrogeologic framework as part of the U.S. Geological Survey Groundwater Resources Program. This dataset contains line features representing regional cross sections presented in this study.

Digital surfaces and thicknesses of selected hydrogeologic units of the Floridan aquifer system were developed to define an updated hydrogeologic framework as part of the U.S. Geological Survey Groundwater Resources Program. This feature class contains well locations where transmissivity estimates were compiled and used for the regional transmissivity map. The well site data contains 1487 transmissivity estimates, in units of feet squared per day. The data was collected using two different testing methods, single- and multi-well aquifer tests (APT) and specific capacity (SPC), 1045 and 442 values respectively.