COMPARISON BETWEEN WENNER ALPHA AND EQUATORIAL DIPOLE CONFIGURATION USING TWODIMENSIONAL ELECTRICAL RESISTIVITY TOMOGRAPHY (ERT) IN UGBOGIOBO COMMUNITY, OVIA NORTH-EAST, EDO STATE, NIGERIA.

ABSTRACT

The purpose of this study is to determine the subsurface resistivity distribution from a 2-D imaging survey and determine the tomography /images of the study area. wenner Alpha and Equatorial Dipole array profiling method was used as a survey technique to give information about lateral changes in the subsurface resistivity, from these measurements the true resistivity of the subsurface was determine by inversion of the measured apparent resistivity values using computer inversion software (RES2DINV). This work was carried out at Ugbogiobo community in Ovia North-East Local Government Area, Edo State. From the images obtain, it was clearfully observe that, different arrays used to map the same region can give rise to very different contour shapes. By virtue of the fact that both have a lower geometric factor of the pair, the equatorial dipole array and the wenner alpha both have a good signal to noise ratio. The equatorial dipole array is more sensitive to anisotropy as the electrode spacing is increased; the horizontal resolution of the equatorial dipole array reduces. The depth of penetration for equatorial dipole array is greater when compared. The equatorial dipole array takes more time and is more tasking to carry out in the field when compared to the Wenner array, it takes practically twice the time