Comparative Analysis of Wenner and Schlumberger Methods of Geoelectric Sounding in Subsurface Delineation and Groundwater Exploration - A Case Study

The accuracy of two common electrode arrays - the Wenner and Schlumberger - used in the geoelectric resistivity method for groundwater exploration has been investigated within a typical area of basement complex. The results of the comparative study show that Schlumberger electrode array has a high investigating depth per unit current electrode separation and is more suitable for subsurface delineation and groundwater exploration. The studies have indicated an average depth to basement of 9.75 m, and six geoelectric formations viz Lateritic top-soil, Clay, Clayey sand, Weathered basement, Fractured basement and Fresh basement.