Datasets / Geodatabase of the available top and bottom surface datasets that represent the Edwards-Trinity aquifer system, Arkansas, Oklahoma, and Texas


Geodatabase of the available top and bottom surface datasets that represent the Edwards-Trinity aquifer system, Arkansas, Oklahoma, and Texas

Published By U.S. Geological Survey, Department of the Interior

Issued over 9 years ago

US
beta

Summary

Type of release
ongoing release of a series of related datasets

Data Licence
Not Applicable

Content Licence
Creative Commons CCZero

Verification
automatically awarded

Description

This geodatabase contains the spatial datasets that represent the Edwards-Trinity aquifer system in the States of Arkansas, Oklahoma, and Texas. 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 (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 or thickness contours. The images and digitized contours are supplied for reference. The extent of the Edwards-Trinity aquifer system encompasses all subunits. It is delineated from the linework of the Edwards-Trinity aquifer system extent and outcrop maps of the U.S. Geological Survey Hydrologic Atlas 730-E (USGS HA 730-E) , available at http://water.usgs.gov/ogw/NatlAqCode-reflist.html . Included are the "no data available" extent polygons where there were no altitude data available for the bottom surface of the Edwards-Trinity aquifer system. These were digitized from USGS HA-730-E, figure 81, and U.S. Geological Survey Water-Resources Investigations Report 85-4116 (USGS WRIR 85-4116), plate 9, and U.S. Geological Survey Water-Resources Investigations Paper 91-4071 (USGS WRIR 91-4071), plate 1. The Edwards-Trinity aquifer system has three aquifer subunits, but for the purposes of this geodatabase only the ultimate top and bottom surface rasters are published. The altitudes for the top surface raster are from georeferenced images of altitude contours from USGS HA-730-E, figures 84, 98 and 114, and USGS WRIR 85-4116, plate 8. In the areas where the Edwards-Trinity top surface underlies the Pecos River alluvial aquifer (USGS HA 730-E, Pecos River Basin alluvial aquifer), and the High Plains aquifer (see USGS HA 730-E, High Plains aquifer), the altitude of the bottom those two aquifers is the top of the Edwards-Trinity aquifer system. The altitudes of the bottom surface raster are from georeferenced images of altitude contours from USGS HA-730-E figure 81, USGS WRIR 85-4116 plate 9, and USGS WRIR 91-4071 plate 1. The altitude contours were interpolated into surface rasters within a GIS using tools that create hydrologically correct surfaces from contour data, derives the altitude from the thickness (depth from the land surface) if necessary, and merges the subareas into a single surface. The primary tool was "Topo to Raster" used in ArcGIS, ArcMap, Esri 2014. ArcGIS Desktop: Release 10.2 Redlands, CA: Environmental Systems Research Institute.