ELECTRICAL RESISTIVITY SURVEY FOR GROUNDWATER POTENTIALS IN SHAKWATU, NIGER STATE, NIGERI

Abstract

Schlumberger configuration of the electrical resistivity method was employed to investigate the groundwater potential in Shakwatu, part of Minna Sheet 164. The area is a part of the crystalline basement complex of Nigeria. A total of 36 VES points was established along six profile lines employing the SAS 4000 Terameter. The maximum current electrode spacing (AB/2) was 100 m while potential electrode separation (MN/2) was set at 15m maximum. Three curve types were noticed from the geoelectric curves; these includes the HA, A and AK curves. Almost all the geoelectric sections of the six profiles are composed of three geoelectric layers. The apparent resistivity of the first and second geoelectric layers ranges from 18 Ωm to 695 Ωm and 11 Ωm to 1782 Ωm respectively with a thickness range of 0.5 m to 1.6 m and 1.1 m to 16.4 m for the first and second layers. The depth to the first layer ranges from 0.5 m to 1.6 m and 1.9 m to 17.5 m for the second geoelectric layers. The third geoelectric layer shows a resistivity range of 493 Ωm to 5631 Ωm which extends to an infinite depth. The potential VES points for groundwater exploitation in the study area includes P2V2 which indicates low to moderate resistivity at greater depth. VES points P6V1 and P1V3 which indicates a fairly thick overburden material are also considered as potential points for groundwater exploitation.