Adetayo Femi folorunso - Department of Earth Sciences, Olabisi Onabanjo University, Ago-Iwoye
elija a ayolabi - Geophysic Program, Department of Physics, University of Lagos
stephen olalere ariyo - Department of Earth Sciences, Olabisi Onabanjo University, Ago-Iwoye

Groundwater search in a basement complex rock using 2-D resistivity imaging survey with Wenner Electrode configuration was carried out in Olabisi Onabanjo University, Main Campus, a suburb of Ago-Iwoye. The results show 3-5 layers which signify different lithological units evcountered as resistivity values were converted into geologically reasonable picture. 2-D resistivity image interpretation indicates low inverted resistivity values sandwich between two high values which is an indication of bedrock depression. Combined interpretation of the 2-D joined with geologic features and topography of the site reveal that the study area can be divided into three hydrogeological sequences; the topsoil variously composed of lateritic soil and sand/sandy clay, followed by highly weathered/fractured rock sequence and deep-seated hard and compact fresh rock section. A deep-drilled tube well site is recommended based on traverse 2 at surface position 75m and up to a depth of 90m±10m because the water flow from the crest to the synclinal water-accumulation zone (depression) which serves as groundwater collection center.

Bedrock, Depression, Fracture, Groundwater