Geoelectrical investigation of Aquifer potentials and subsurface lithology in Akwa Ibom State polytechnic Ikot Osurua campus, Akwa Ibom State, Nigeria:-Inyang, Udeme U

ABSTRACT

The study was carried out to investigate the aquifer potentials and subsurface lithology in Akwa Ibom State Polytechnic Campus Ikot Osurua. The Study area lies between latitude 5ᴼ09¹ and 5ᴼ40¹N and longitude 7ᴼ18¹ and 7º20¹E. It is underlaid by sedimentary formation of late tertiary and holocence ages. A total of twelve (12) vertical electrical soundings (VES) were conducted using the integrated Geo-instrument Service (IGIS) resistivity meter to generate the field data. The schlumberger sounding was carried out with current electrode spacing (AB) ranging from 1-300 m. The distance used for the potential electrode spacing (MN) ranged from 0.25 -10 m. The field data obtained were subjected to interpretation by partial curve marching and then by computer iteration using IP12WIN software. The interpreted results were constrained by lithologic log to produce the geo-electric sections of the subsurface. The geoelectric section showed three(3) to five (5) layered subsurface  of top soil, Lateritic  sand, Consolidated Sand, Clay sand and aquifer layer with different curve types which were Q, KA, K, KK and HQ. Aquifer characterization of the area showed the aquifer resistivity and depths ranging from 30.6 to 6489 Ωm and 50 to 100 m respectively although it varies in some location, this is an indication of the presence of fresh groundwater.