Rheannon M. Hart Brian R. Clark Susan E. Bolyard 2008 Vector Digital Data Set (Polygon) Reston, VA U.S. Geological Survey https://water.usgs.gov/lookup/getspatial?sir2008-5098_ALVM_extent U.S. Geological Survey 2008 Scientific Investigation Report 2008-5098 Reston, Virginia U.S. Geological Survey https://pubs.usgs.gov/sir/2008/5098/ Outcrop and subcrop extent of the Mississippi River Valley Alluvial Aquifer in Alabama, Arkansas, Illinois, Kentucky, Louisiana, Mississippi, and Tennessee. The purpose of these data is to provide a digital map of the surface of select hydrogeologic units within the Mississippi Embayment aquifer system. 2006 2008 publication date Complete None planned -94.096568838 -86.761931243 37.452593475 31.200592135 USGS Thesaurus Mississippi Embayment Regional Aquifer Study MERAS groundwater water use water availability GIS inlandWaters USGS Metadata Identifier USGS:fa9ad40b-86ab-497e-9ac4-809a1d721b4d Geographic Names Information System Mississippi embayment West Gulf Coastal Plain East Gulf Coastal Plain Mississippi Alluvial Plain None. Please see 'Distribution Info' for details. None. Users are advised to read the data set's metadata thoroughly to understand appropriate use and data limitations. U.S. Geological Survey, USGS Southeast Area Rheannon M Hart Hydrologist mailing address

401 HARDIN RD

Little Rock AR 72211 501-228-3664 501-228-3601 rmhart@usgs.gov https://water.usgs.gov/GIS/browse/sir2008-5098_ALVM_extent.gif Illustration of the dataset. GIF Jeff Brantly and Ron Seanor, USGS Louisiana Water Science Center, Mike Bradley and Jack Carmichael, USGS Tennessee Water Science Center, Heather Welch, Jeannie Barlow, and Claire Rose, USGS Mississippi Water Science Center, Lafayette and Rolla Publishing Service Centers Environment as of Metadata Creation: Microsoft Windows 7 Version 6.1 (Build 7601) Service Pack 1; ESRI ArcCatalog 10.2 (Build 3497) Service Pack [N/A] (Build [N/A]) The correlation altitude on the geophysical logs and the altitude of the interpolated digital hydrogeologic surface was determined at every location a geophysical log control point existed. The differences between the geophysical log control point and the interpolated digital hydrogeologic surface at each location represents how accurate the interpolated digital hydrogeologic surface is to the "real world" geophysical log control point. Mean differences (correlation altitude on the geophysical logs minus interpolated digital hydrogeologic surface altitude) is the average difference between the unit correlation altitudes on the geophysical logs and the altitudes of the interpolated digital hydrogeologic surfaces at the location of the geophysical log control point. Minimum and maximum differences are those measured between the unit correlation altitudes on the geophysical logs and the altitudes of the interpolated digital hydrogeologic surfaces; absolute mean error is the error between the unit correlation altitudes on the geophysical logs and the altitudes of the interpolated digital hydrogeologis surfaces. No formal logical accuracy tests were conducted. The interpolated digital hydrogeologic surface covers the extent to which the presumed extent of the hydrogeologic unit in subcrop exists, and therefore, covers the extent at which the geophysical log control points exist. Data set is considered complete for the information presented, as described in the abstract. Users are advised to read the rest of the metadata record carefully for additional details. A formal accuracy assessment of the horizontal positional information in the data set has not been conducted. A formal accuracy assessment of the vertical positional information in the data set has either not been conducted, or is not applicable. Please contact Originators for processes. 20140707 Vector G-polygon 34 USA Contiguous Albers Equal Area Conic USGS version (ESRI Full Name: USA_Contiguous_Albers_Equal_Area_Conic_USGS_version) 29.5 45.5 -96.0 23.0 0.0 0.0 coordinate pair 0.6096 0.6096 Meter D_North_American_1983 GRS_1980 6378137.0 298.257222101 Attribute Table Table containing attribute information associated with the data set. Producer defined Id Identifier Producer defined 0 3 Shape_Length Length of feature in internal units. ESRI 11.6767621743284 2281301.01408242 Shape_Area Area of feature in internal units squared. ESRI 4.89387325672767 76448398343.9178 The entity and attribute information provided here describes the tabular data associated with the data set. Please review the detailed descriptions that are provided (the individual attribute descriptions) for information on the values that appear as fields/table entries of the data set. The entity and attribute information was generated by the individual and/or agency identified as the originator of the data set. Please review the rest of the metadata record for additional details and information. U.S. Geological Survey Michael Ierardi IT Specialist mailing and physical

445 National Center

Reston Virginia 20192 USA 1-888-275-8747 (1-888-ASK-USGS) mierardi@usgs.gov Downloadable Data Although these data have been used by the U.S. Geological Survey, U.S. Department of the Interior, no warranty expressed or implied is made by the U.S. Geological Survey as to the accuracy of the data. The act of distribution shall not constitute any such warranty, and no responsibility is assumed by the U.S. Geological Survey in the use of these data, software, or related materials. The use of firm, trade, or brand names in this report is for identification purposes only and does not constitute endorsement by the U.S. Geological Survey. The names mentioned in this document may be trademarks or registered trademarks of their respective trademark owners. Shapefile 1.2 https://water.usgs.gov/GIS/dsdl/sir2008-5098_shp.zip None. No fees are applicable for obtaining the data set. 20201117 U.S. Geological Survey Michael Ierardi IT Specialist mailing and physical address

445 National Center

Reston VA 20192 USA 1-888-275-8747 (1-888-ASK-USGS) mierardi@usgs.gov FGDC Content Standards for Digital Geospatial Metadata FGDC-STD-001-1998