Geoelectric Investigation of Groundwater Potentials of Gidanwaya, Maikukele, Minna, Niger State

Abstract

A geoelectric investigation of groundwater potential at Gidan-Waya, Maikunkele, Minna, Niger State Nigeria, was carried out using Electrical Resistivity method, by employing both Vertical Electrical Sounding (VES) and Electrical Resistivity Profiling (ERP). The aim of the survey was to determine the groundwater potentials of Gidan-Waya. Geosensor Terameter Model DDR1 was employed for the survey. The study area lies within the Basement Complex region of Northern Nigeria. A total of ten profiles (A -I) with twenty stations along each profile at intervals of 50 were investigated. Electrical Resistivity Profiling (ERP) was first employed using Werner array configuration of equal electrode spacing of 30 m, probing the depth of 45 m for each station. The ERP results were used to produce an apparent resistivity contour map form which the promising points wre obtained for Vertical Electrical Sounding (VES). Twenty two points were found to be promising and twenty were fully subjected to Vertical Electrical Sounding as two points were affected by electrical noise due to the presence of high tension. The VES has a maximum current electrode separation (AB/2) of 100 m. The results obtained from VES plots reveal three distinct geoelectric layers: the top soil, the weathered/fractured layer, the fractured/fresh basement layer. Three distinct curve types were observed for the entire Ves plotted curves. H-type was observed for VES A17, A18, C11, C19, D13, E9, E18, F9, G14, G17, H3, H12, I18, I19, J14, and J19. A-type was observed for B2, and D17, while K-type was observed for onlyB12. The best points delineated as groundwater potentials are E18, A18, G14, D13, G17 and F9 with aquifer thickness of 23.9 m, 21.4 m, 18.3 m, 25 m, 13.5 m, and 11 m respectively. Other points possessing groundwater potential are C19, I19, I18 and J19 with aquifer thickness of 9.1 m, 8.7 m, 8.5 m and 8,2 m respectively.