Geoelectrical Investigation For Groundwater Potential and Aquifer Protective Capacity of Overburden Units at Unions Site, Gidankwano Campus, Federal University of Technology, Minna, North Central, Nigeria

Abstract

Evaluation of groundwater potential was carried out at Northern part of Gidan kwano campus, Federal University of Technology, Minna. Schlumberger electrode configuration was adopted with maximum current electrode spacing (AB/2) of 100 m. The profile separations of 100 m with inter vertical electrical soundings (VES) point spacing of 100 m. Total of sixty (60) vertical electrical soundings station were covered. The interpretation revealed three distinct geologic layers. These include topsoil with resistivity values between 11.41 and 1009 ohm-m and thickness is relatively thin and ranges between 1 and 6m, The weathered/fractured layer has resistivity values from 11 to 963ohm-m with thickness from1 to 45m indicate high degree of weathered/fracture and/or water saturation, The fresh basement has resistivity values that range between12 and 2983 ohm-m. All the soundings 3-layered and characterised by A, H and Q curve types. The area was categorised into high, medium and low groundwater potential zones. Twenty five (25) VES points were delineated as ground water zones having weathered/fractured resistivity varies between 100 and 963 Ωm and thickness ranging from 5 – 45m. The characteristic longitudinal unit conductance from 0.01 to 1.84 mhos. About 30% of the VES points fall within the good rating suggesting generally poor overburden protective capacity around the study area.