Shallow soil characteristics were mapped near Shellmound, Mississippi, using the DualEM 421 electromagnetic sensor in October 2018. Data were acquired by towing the DualEM sensor on a wheeled cart behind an ATV, with the sensor at a height of 0.432 meters (m) above the ground surface. Approximately 175 line-kilometers of data were acquired over an area of nearly four square kilometers, with 25 m separation between survey lines. Data were manually edited for noise sources such as powerlines or other buried structures, and averaged to regular output soundings every 5 m along survey lines. This data release contains the processed data that have been averaged and culled to produce final resistivity models. Digital data of the processed soundings are provided and fields are defined in the data dictionary.