Application of Vertical Electrical Sounding for the Investigation of Groundwater potentials at Umaru Musa Yar'adua University, Katsina

Abstract

The population of Umaru Musa Yar’adua University, Katsina (the study area) is increasing every session and therefore, sources of safe water in the area is need to be improved; more importantly groundwater. Recently, water supply from Zobe Dam is connected to the study area but still it does not solve the water supply problem; hence other alternative is needed in order to supplement for existing. Various groundwater exploration programs that have been carried out in the study area have not yielded the required results. However, there was no academic research on groundwater in the study area. VES has been carried out in order to investigate groundwater potential, to determine the lithology, the resistivity value associated with the groundwater and prospect locations for groundwater exploration. The ABEM Terrameter SAS 4000 was used and a Schlumberger array was employed to accomplish this task by obtaining resistance of 7 VES points in the study area with a maximum current electrode spacing (AB) of 240 m. The VES data obtained were processed using IPI2Win software. The VES results in correlation with the and borehole log data have revealed that the near-surface materials with resistivity value between about 1 Ωm to 7,985 Ωm is representing 4 to 5 layers consisting of first layer mostly top soil and laterite, having resistivity values between 403 Ωm to 7,985 Ωm with thickness from 0.498 m to 1.21 m; second layer with resistivity values from 43.6 Ωm to 114.4 Ωm having thickness from 1.34 m to 4.71 m interpreted commonly as sandy clay and sandy soil; third layer showing resistivity values between about 1 Ωm to 38.4 Ωm is found to be a saturated layer with water; fourth layer generally indicating weathered basement with resistivity values from about 1 Ωm to 7.57 Ωm having thickness of 36.1 m and or infinite thickness, and fifth layer showing vary low resistivity value with infinite thickness. The result shows that the groundwater exploration should be conducted at VES 1, 2, 3, 4, and 5 at a depth from about 30 m to 50 m revealing low resistivity values ranging from 2 Ωm to 391 Ωm however, VES 6 and 7 indicates high resistivity value and therefore poor groundwater potentials.