Preliminary Geophysical Investigation to Delineate the Groundwater Conductive Zones in the Coastal Region of Akwa Ibom State, Southern Nigeria, around the Gulf of Guinea

George N. Jimmy, Akpan A. Otu, Umoh A. Asuquo

Department of Physics, Akwa Ibom State University, Akwa Ibom, Nigeria.
Department of Physics, University of Calaber, Calaber, Nigeria.
Department of Physics, University of Uyo, Uyo, Nigeria.

DOI: 10.4236/ijg.2013.41011                

Abstract

This paper presents the first work of its kind within the confines of the study area. It unravels the distribution of the layers of conductive sand and their depths of interaction between freshwater from fresh sands and saltwater within the conductive layers in the coastal region of Akwa Ibom State (Nigeria) around the Gulf of Guinea. Vertical electrical sounding (VES) data whose fidelity was achieved by constraining the data by the available nearby logged borehole information during interpretation was the method applied. In the western region of the study area, the ferruginized and saline water layer is found within the depth range of 22 to 75 m deep. In the northern zone, conductive sandy layer is found within 50 to 210 m and in the eastern zone, the saline and ferruginized sandy layer is found within the depth of 88.5 m and above. Generally, the horizontal and vertical cross sections of the subsoil and the flow regime from water table depths have been delineated. With these information, water can be tapped in the area with caution and the flow direction determined can be used as input parameter in detailed contamination study.

Keywords

Freshwater; Saltwater; Ferruginized and Saline Sands; VES

Conflicts of Interest

The authors declare no conflicts of interest.

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