Groundwater Exploration in Nifor Area of Edo State using Electrical Resistivity Method

Groundwater exploration was carried out in Nigerian Institute for Oil Palm Research (NIFOR) community in Ovia North-East Local Government Area of Edo State, Nigeria using electrical resistivity method. It lies between latitude of 6° 32′ 12.12″ N and longitude of 5° 37′ 23.52″ E. The geology of the study area is overlain by the Benin Formation. The study area is hilly and had little natural topographical variations. The topography is generally low, lying area with gentle slope. The vegetation is made up of trees, shrubs and grasses. Their main livelihood is farming and trading. The method employed in this study involves the measurement of apparent resistivity with depth and also for measurement underlying rocks structure such as sedimentary beds or depth of water table. The equipment employed for taking Vertical Electrical Sounding (VES) readings was Parsi (A.C) Earth Resistivity meter. The soundings were taken using Schlumberger array with maximum current electrode separation of 430m.A total of four locations were surveyed along Cattle Yard Road, Iyamu Street, and Church Street and to Feeding 31 Street (locations 1, 2, 3 and 4). The data acquired were interpreted using computer software IPI2WIN. It was discovered that all VES locations have six layers with apparent resistivity ranging from 0.675Ωm to 616291Ωm with depth ranging from 0.5m to 129m.The major lithologic units penetrated by the sounding curve were lateritic sand, clay and fine wet sand. The results from the survey areas were correlated with the existing borehole driller’s log of NIFOR for proper interpretation. The results defined the existence of aquifer with low resistivity of 0.675Ωm immediately after 5th layer in the areas under investigation. The existence of a probabilistic aquifer layer propose the study area may be a potential location for groundwater exploration, and I therefore recommend that the results of this research work should be used by drillers before a borehole is sunk.