Vertical electric sounding investigation of aquifers in the Ekpoma area of Nigeria.

Abstract

Aquifers or water bearing formations existence was investigated in Eguare-Egoro, Ekpoma, Edo State, Nigeria by using vertical electric sounding (VES) of schlumberger array. The array was employed with minimum drilling spread of 2m and maximum spread of 500m. The need to investigate aquifer existence in Eguare-Egoro becomes inevitable because of acute shortage of water in the area. The acute shortage of water in the area is primarily due to its unfavourable climate and geology that made the aquifer level to be very deep. This great depth often leads to borehole failure considering the great pumping distance of the machine. Interpretation of data was done initially by curve which provided computer iterative model. The results obtained were presented in the form of geoelectric sections which was then interpreted using bore-hole log as a control to detect various lithologies encountered and aquifers existence in the area. The aquifers are probably sands, clays, sand stones and or sands with clay intercalation. The resistivity values for the existed aquifers detected vary from 40 ohm-m to 12,000 ohm-m.

JONAMP Vol. 11 2007: pp. 597-604