Investigation of Geophysical Properties to Delineate Aquifer Units in Ibusa in the Northern Part of Delta State, Nigeria

Ibusa has complex topographic settings that make good knowledge of lithological stratigraphy vital before drilling of water borehole. Appropriate standard methods of Vertical Electrical Sounding- VES and Schlumberger array were employed in data acquisition. Processed data revealed geoelectric curve of QHA type which has five layers, comprising of sandy topsoil with resistivity of 223.1Ωm and thickness of 0.7m. The second layer is composed of sandy clay with resistivity of 69.2Ωm at the depth 3m having thickness of 2.3m. The third layer is composed of clayey sand with resistivity of 33.9Ωm and thickness of 7.5m, this layer has low porosity and permeability. It acts as a good filter to the aquifer below. At the depth of 63m is the fourth layer with resistivity of 174.5Ωm and thickness of 52.5m. This is the depth that groundwater can be exploited in wet and dry seasons. Electric current terminated at fifth layer with resitivity of 621.3Ωm. It is recommended that boreholes be drilled to minimum depth of 63m. Also, the recommended depth along the VES point should not be a standard for other prospective groundwater exploration, but only a guide due to varied topography in the study area.