Geoelectrical Investigation of Groundwater Potential in University of Abuja, Main Campus

Abstract

Electrical resistivity techniques of geophysical prospecting have been used to evaluate the groundwater potential of the University of  Abuja Health Services Centre at the main campus. This research aims to identify suitable locations for productive wells and boreholes,  determine the depth of the bedrock, as well as measure resistivity and overburden thickness. The survey employed Vertical Electrical  Sounding (VES) along five profiles, comprising fifty (50) VES stations covering the survey area. The resistivity data obtained are analysed  using IPI2win software. The analysis of the resistivity data revealed that the survey area can be divided into four geoelectric layers:  topsoil, clayey sand, weathered layer, and fresh basement. The resistivity values of these layers range from 38.7-1427 Ωm, 16.2-310 Ωm,  32.1-1714 Ωm and 1007-9528 Ωm respectively. The fresh basement layer was found to have an infinite thickness. Significantly, potential  regions with low resistivity values indicating the presence of groundwater were identified at a depth of 18.3 m. Furthermore, the average  overburden thickness in the study area was 35 m while the longitudinal conductance of the overburden ranges from 0.04 – 1.87 mho.  Results obtained indicate the main aquifer in the area consists of a thick weathered layer of overburden and a weathered basement with  relatively low resistivity, suggesting a potentially productive groundwater yield. This information is crucial for future planning and  decision-making regarding the siting of wells and boreholes and the sustainable utilisation of groundwater resources in the University of  Abuja main campus.