Geo-Electrical Evaluation of Aquifer Characteristics and Groundwater Potential in Sango - Kulende Area, Ilorin, Nigeria
Abstract:An
electrical resistivity survey involving vertical electrical sounding (VES) has
been carried out for groundwater exploration around Sango-Kulende area in
Ilorin South Local Government Area of Kwara State, Nigeria. This was performed with
a view of determining the aquifer potential and identifying suitable sites
where viable boreholes could be dug for long term supply of potable water for
the inhabitants of the area. The survey was carried out using a powerful campus
ohmega portable resistivity meter while a total of ten (10) VES stations were
completed in three evenly spaced profiles using Schlumberger electrode
configuration. A maximum half electrode distance of 100m was utilized and the
data acquired were analyzed and interpreted with the aid of computer iteration
techniques using the Inverse lite and AGCross software. Interpretations of the
resistivity data revealed the presence of three interpretable geo-electric
layers and aquifer which is mainly an alluvial aquifer. The top lateritic soil
has a resistivity value ranging from 150 to 1100 and
thickness of 2.0 to 8.0m. The weathered basement has a resistivity ranging from
9.0 to450 with
thickness 10.0 to
25.0m, while the fresh basement layer has
resistivities greater than 700. The surveyed area is saturated zones and
considered to be a good point for locating a groundwater drilling tube of high
quality except for VES 4 among all the VES stations.