Investigation of Aquifer Quality in Bonny Island, Eastern Niger Delta, Nigeria using Geophysical and Geochemical Techniques

Abstract

The deterioration of aquifer quality in the coastal areas of Eastern Niger Delta, Nigeria was investigated in this study using geophysical and geochemical methods. Vertical Electrical Soundings (VES) were carried out in the Bonny Island utilizing surface Schlumberger electrode configuration with an ABEM Terrameter (SAS 1000) while soil and groundwater samples were collected and analyzed for relevant for relevant geochemical parameters. The computer modeled curve generated from the VES indicates a saline (30-90 m) and ferruginous (90-180 m) subsurface. Freshwater less in salt and iron content are found at depths between (180-300 m). The study has shown that Schlumberger sounding resistivity method is an efficient tool for investigating the saltwater-freshwater interface in coastal areas. It is recommended that down-the-hole geophysical logging should be carried out after drilling so that the screen can be installed at appropriate non-saline aquiferous zone.