Geophysical Determination of Aquifer Parameters in Basement Complex Rocks through Vertical Electrical Sounding Data Analysis from part of Ilorin East Southwestern Nigeria

Abstract

This research employed vertical electrical sounding data collected from the Ilorin East region of Southwest Nigeria to analyse aquifer properties within Basement Complex rocks. Its objective was to assess the aquifer's attributes in the area through statistical methods and electrical resistivity. Geoelectrical profiling revealed four distinct layers beneath the surface: lateritic layer, topsoil, weathered rock, and fresh basement. The third and fourth layers were identified at depths between 8.47 and 33.2 meters, with aquifer resistivity values ranging from 76.6 to 1576 Ωm. The fractured rocks in the region possess a moderate permeability due to moderate weathering. The aquifer's characteristics were evaluated based on four parameters: transmissivity, apparent resistivity, depth to bedrock, and aquifer thickness. The findings ranging from 0.74- 33.2 m indicate varying groundwater potential across the study area, ranging from low to high.