Re-Construction of Palaeo-Sedimentation Processes of Aquifers underlying Igueben and Environs using Geo-Electrical Resistivity Signature and Borehole Data

Abstract

ISSN: XXXX-XXXX Abstract: Igueben is located in the central of Edo State, Nigeria. It has neighbouring towns; Ogwa, Ugbegun, Ugiogba, Ebelle, and Ekpon. These towns have the same aquifer but significant variations in the water table. However this study was intended to unravel the salient ancient hydrological processes that occurred in the study area which resulted to this variation. Vertical electrical sounding (VES) data and borehole data of the area were integrated to generate geoelectrical resistivity section of the area, to identify the aquifer trends, body, and shape in order to re-construct the palaeo-sedimentation processes of the aquifers that underlie Iguebe and the neighbouring towns. The inversion model result for the seven VES conducted in the study area showed that the curve types are HQA, AHA, A, AHA, AHA, HAQ, and AQA, respectively. These curve type suggested that the aquifer type is arenite sandstone aquifer that has been transported from a long distance. The geo-electrical pattern and shape showed that Igueben and Ogwa (shallow marine) are the point of deposition from where other nearby towns (Ugbegun, Ugiogba, Ebelle, and Ekpon) sourced their aquifer by gravity settling from suspended sediments in water body into adjacent deep marine environment (Ugbegun, Ugiogba, Ebelle, and Ekpon).This geological processes were responsible for the variation in the water table in the study area.