2D and 3D Geoelectrical investigation of Hydrocarbon impacted sites in Erhoike Community, Ethiope East local Government Area, Delta State, Nigeria

Abstract

Hydrocarbon contamination occurs as a result of corrosion of buried pipelines, sabotage of oil and gas facilities and spills during petroleum product transportation. This study was undertaken to characterize hydrocarbon impacted sites in Erhoike community, Ethiope East local government area, Delta State, Nigeria using ten (10) transects were established in grid format to attain geoelectric data that were inverted to yield 2D resistivity structure and 3D depth slices respectively. The 2D results show that the hydrocarbon impacted zones are marked by very high resistivity values ranging from 637 ohm-m to more than 17000 ohm-m from the surface to a depth in excess of 31.9 m in places within the study area. In the same vein, the 3D result indicated that bulk of the contaminant has progressively moved to deeper depth with most of the plume found at between 25.0 – 33.7 m. The data obtained show that the site has been impacted by hydrocarbon contaminant.  It also shows that the hydrocarbon moved downwardly at greater depth into the subsurface, through a porous medium - sandy layer. Finally, the study has demonstrated the effectiveness of the adopted geophysical techniques in delineating hydrocarbon contamination.