High-Resolution Quasi-3D Electric Resistivity Tomography for Deciphering Groundwater Potential Zones in Lateritic Terrain

Groundwater is under constant threat of exploitation with increasing demands. Therefore, there is a need for more advanced methods for exploring potential groundwater zones to meet people requirements. Groundwater in hard terrain areas is present in fractured zones, whereas in lateritic terrain it occurs in layered strata. Electrical resistivity tomography (ERT) is an advanced geophysical technique used in our present study; a quasi-3D ERT survey was conducted using different arrays. 2D Geophysical data were acquired along 18 ERT profiles of Wenner and Wenner-Schlumberger arrays and 13 ERT profiles of Dipole-Dipole array. Each profile of 200 m length was kept parallel to each other at 5 m spacing in the E-W direction. The inverted response was generated and, based on resistivity distribution, different geological layers of clay, sand and laterite were delineated using various ERT arrays. A conductive zone was marked as a potential aquifer zone at depths of 7-10 m below ground level. Thus, the quasi-3D geoelectrical approach was applied successfully in a lateritic environment for deciphering potential groundwater zones.