Title: High-Resolution Airborne Geophysical Survey of the Shellmound, Mississippi Area By Bethany L. Burton, Burke J. Minsley, Benjamin R. Bloss, Wade H. Kress, James R. Rigby, and Bruce D. Smith 2020 U.S. Geological Survey Scientific Investigations Map 3449 Data release available at https://doi.org/10.5066/P9D4EA9W ABSTRACT: In late February to early March 2018, the U.S. Geological Survey acquired 2,364 line-kilometers (km) of airborne electromagnetic, magnetic, and radiometric data in the Shellmound, Mississippi study area. The purpose of this survey is to contribute high-resolution information about subsurface geologic structure to inform groundwater models, water resource infrastructure studies, and local decision making. The Shellmound region hosts a managed aquifer recharge (MAR) pilot project, developed by the Agricultural Research Service of the U.S. Department of Agriculture. The MAR pilot project is investigating the use of bank filtration along the Tallahatchie River as a source for recharge in areas of significant groundwater decline. Direct injection into the Mississippi River Valley Alluvial aquifer (MRVA) occurs about 3 km from the extraction gallery. Understanding the structure of the aquifer, including both shallow and deep confining units, is important for the success of this pilot MAR study and may be even more important for potential future large-scale MAR projects and groundwater model development efforts. DISCLAIMERS: Although these data have been processed successfully on a computersystem at the U.S. Geological Survey, no warranty, expressed or implied is made regarding the display or utility of the data on any other system, or for general or scientific purposes, nor shall the act of distribution constitute such warranty. The USGS or the U.S. Government shall not be held liable for improper or incorrect use of the data described and/or contained herein. This map or plate is offered as an online-only, digital publication. Users should be aware that, because of differences in rendering processes and pixel resolution, some slight distortion of scale may occur when viewing it on a computer screen or when printing it on an electronic plotter, even when it is viewed or printed at its intended publication scale. Any use of trade, product or firm names is for descriptive purposes only and does not imply endorsement by the U.S. Geological Survey. Although this information product, for the most part, is in the public domain, it also may contain copyrighted material as noted in the text. Permission to reproduce copyrighted items for other than personal use must be secured from the copyright owner. REPORT FILES: The map for this report is located at and can be downloaded via the web from the U.S. Geological Survey publications website at https://doi.org/10.3133/SIM3449. List of files: 00ReadMe_SIM3449.txt SIM3449_sheet1.pdf (geologic map, list of units, map explanation, airborne survey flight lines, radiometric ternary data, magnetic anomaly data, and accessory figures) SIM3449_sheet2.pdf (geologic map, list of units, map explanation, resistivity maps, accessory figures, and cross sections of resistivity and hydrostratigraphy) How to Obtain the Digital Report Files: The map sheet can be obtained via the internet from the U.S. Geological Survey publications website. Go to the web page at https://doi.org/10.3133/SIM3449 and follow the directions to download the files. The main product is a Portable Document Format (.pdf) map, which requires Adobe Acrobat for viewing. These Portable Document Format (PDF) files can be downloaded, from which paper copies may be printed. Acrobat software runs on a variety of systems, and is available for download free of charge from Adobe at http://www.adobe.com. Suggested citation: Burton, B.L., Minsley, B.J., Bloss, B.R., Kress, W.H., Rigby, J.R., and Smith, B.D., 2020, High-resolution airborne geophysical survey of the Shellmound, Mississippi area: U.S. Geological Survey Scientific Investigations Map 3449, 2 sheets, https://doi.org/10.3133/sim3449. The digital GIS files constituting the geologic map database of this report can be obtained from the U.S. Geological Survey via the Internet from ScienceBase. ScienceBase link: https://doi.org/10.5066/P9D4EA9W ScienceBase suggested citation: Burton, B.L.., Minsley, B.J., Bloss, B.R., Rigby, J.R., Kress, W.H., and Smith, B.D., 2019, Airborne electromagnetic, magnetic, and radiometric survey, Shellmound, Mississippi, March 2018: U.S. Geological Survey data release, https://doi.org/10.5066/P9D4EA9W. ArcReader may be downloaded free of charge from https://www.esri.com/en-us/arcgis/products/arcreader for viewing additional files included in this report. This SIM is offered as an online-only, digital publication. Users should be aware that, because of differences in rendering processes and pixel resolution, some slight distortion of scale may occur when viewing it on a computer screen or when printing it on an electronic plotter, even when it is viewed or printed at its intended publication scale.