The potentiometric map of the lower Wilcox aquifer is one of a series of maps, prepared by the U.S. Geological Survey in cooperation with the Mississippi Department of Natural Resources , delineating the potentiometric surfaces of the major aquifers in Mississippi. In the outcrop area of the lower Wilcox aquifer the potentiometric surface is strongly affected by recharge from precipitation, by topography, and by drainage of the aquifer by streams. The potentiometric surface slopes downward generally to the west away from the area of outcrop but is strongly affected by pumpage from public and industrial wells in several areas in northwestern Mississippi. This pumpage has caused a large shallow depression in the potentiometric surface in the Marks-Batesville-Charleston-Tunica area. (USGS)