Geoelectrical imaging for shallow site investigation at Ekiugbo in Uhunmwode Local Government Area of Edo State, Nigeria

A geoelectrical imaging survey was conducted at Ekiugbo in Uhunmwode Local Government Area of Edo State, Nigeria, for Shallow site investigation in order to determine the subsurface lithology using Pole-Dipole array and SAS 1000 Terrameter for the acquisition of field data. Global position system (GPS) was used to geolocate the position of the data acquisition as longitude 005006’20.6”, latitude 05039’24.7”. The data were subjected to an inversion using RES2DINV computer software for analysis and interpretation. The lateral spread was 280 m and the vertical penetration was 184 m. The resistivities of the various lithological profiles ranges 138 Ωm – 54938 Ωm.Keywords: Geoelectric, GPS, heterogeneous. imaging, lithology, res2DINV, resistivity, subsurfac

Geophysical Investigation of Some Flood Prone Areas in Ota, Southwestern Nigeria

Thirteen shallow vertical electrical resistivity soundings using Schlumberger array were conducted within the study area. The aim of the study was to investigate the nature of the subsurface in some flood prone areas within the study area by determining the lithology and the corresponding inverse model resistivities at the depths investigated and hence the cause of flooding in the area during the wet season. The resistivity sounding data were collected along seven traverses using a Campus Tigre terrameter. The observed data were interpreted quantitatively using curve matching and computer assisted iteration method. The results of the inversion show a lithology that comprises of the top soil and a paralic sequence of sand and lateritic clay at the depth investigated with varied resistivity and thickness. The flooding is thought to be due to the shallow lateritic clay layer at an average depth of 5.2 m with thickness ranging from 14.5m to 31.8m at the various points of investigation and the shallow depth of the water tabl