Preliminary Assessment of Groundwater Potential and Water Facie Classification in Parts North-Central Nigeria

Abstract

A total of fifty-four (54) vertical electrical soundings were carried out across nine randomly selected communities within Kogi and Kwara State using ABEM SAS 2000 Terrameter. Thirty-seven (37) water samples were collected for major ions’ concentration determination and their suitability for drinking and irrigation purposes were evaluated using World Health Organization (WHO) and Standard Organization of Nigeria (SON) standards. Results of Vertical Electrical Sounding showed that the area is underlain by 4-5 geoelectric layers consisting of top soil, clayey layer, partly weathered/fractured basement and the fresh basement with resistivity values. HA is the dominant curves. Overburden thickness deduced from the VES revealed about 55.5% of the area have overburden thickness less than10m, about 31% fall within 10-20m, 9.3% in the range of 20-30m and 3.7% have overburden thickness greater than 30m. 2D Aquifer thickness map reveal that the aquifers thicken towards the east. Bedrock topography reveals a southwestern groundwater flow. The bedrock resistivity distribution in agreement with the overburden thickness shows a small percentage of the area with high saturation of groundwater. Hydrochemical investigation revealed that the water is suitable for both drinking and irrigation purposes when compared to WHO and SON standards.