Geophysical investigation of aquifer repositories in Ibagwa Aka, Enugu State, Nigeria, using electrical resistivity method

Abstract

This study to investigate the aquifer repositories of Ibagwa Aka, Igbo Eze South Local Government Area, Enugu state was carried out using vertical electrical sounding (VES) method. Ten vertical electrical soundings were carried out across the study area applying the Schlumberger electrode configuration and the data were analysed using the WinResist software package, which delineated the geoelectric layers in terms of their resistivities, depths and thicknesses. The aquifer resistivity was obtained to be within the range of 2681.3–16255.0 Ωm with an average value of 9163.8 Ωm while the aquifer thickness ranged from 47.4 to 128.0 m with an average value of 60.71 m. The geohydraulic parameters estimated from the geoelectric data showed the following results; the hydraulic conductivity ranging from 0.0456 to 0.4278 m/day, transmissivity ranged from 2.1611 to 54.7536 m2/day and aquifer porosity ranging from 11.6040 to 21.6787%. The protective capacity of the aquifer was determined using the longitudinal conductance, which has a range of values of 0.0029–0.3010 Ω-1 and an average value of 0.0187Ω−1. The results show a general low groundwater potential delineated from the values of the hydraulic conductivity and transmissivity and also the aquifer layer is vulnerable to contamination over time. The hydrogeological information gathered from the results of this study will be helpful in groundwater exploration and management in Ibagwa Aka and will also serve as a guide for future research.