Geo-Electrical Evaluation of Aquifer Characteristics and Groundwater Potential in Sango - Kulende Area, Ilorin, Nigeria

An electrical resistivity survey involving vertical electrical sounding (VES) has been carried out for groundwater exploration around Sango-Kulende area in Ilorin South Local Government Area of Kwara State, Nigeria. This was performed with a view of determining the aquifer potential and identifying suitable sites where viable boreholes could be dug for long term supply of potable water for the inhabitants of the area. The survey was carried out using a powerful campus ohmega portable resistivity meter while a total of ten (10) VES stations were completed in three evenly spaced profiles using Schlumberger electrode configuration. A maximum half electrode distance of 100m was utilized and the data acquired were analyzed and interpreted with the aid of computer iteration techniques using the Inverse lite and AGCross software. Interpretations of the resistivity data revealed the presence of three interpretable geo-electric layers and aquifer which is mainly an alluvial aquifer. The top lateritic soil has a resistivity value ranging from 150 to 1100 and thickness of 2.0 to 8.0m. The weathered basement has a resistivity ranging from 9.0 to450 with thickness 10.0 to25.0m, while the fresh basement layer has resistivities greater than 700. The surveyed area is saturated zones and considered to be a good point for locating a groundwater drilling tube of high quality except for VES 4 among all the VES stations.