Seasonal Comparison of Potential Groundwater Aquifer in Ijebu-Ife, South-West, Nigeria, using Dipole-Dipole Array and Electromagnetic Methods

Abstract

Seasonal comparison of potential groundwater aquifer unit using integrated geophysical methods at Ijebu-Ife, Ogun State, South-west, Nigeria was investigated. The fieldwork employed two seasons (dry and wet seasons). The electromagnetic method employed the Very low frequency and its data was acquired during the dry and wet seasons along with five profiles of Dipole-dipole array covering 500 m length using ABEM WADI VLF equipment and was processed using the KAROUS-HJELT software. The 2 – D Dipole-dipole data were also acquired along with five (5) traverse for both seasons making a total number of ten (10) and was processed with DIPROFWIN software. The results of the Integrated Dipole-Dipole and VLF-EM data identified three geoelectric layers based on its electrical resistivity and conductivity distribution. The study identified a clayey sand horizon which constitutes a good aquifer zone. The study reveals in, comparison, that during the dry season, all layer resistivities are high with low depth while during the wet season; all layer resistivities are low with high depth. Also, conductivity during the wet season is high at high depth than conductivity which is low at low depth during the dry season. The study concluded that, in water exploration, drilling of water should be done during the dry season in other to locate the exact depth of water.