Estimation of groundwater potential using surficial resistivity measurements: A case study from parts of Makurdi Benue State Nigeria
A geophysical survey involving vertical electrical sounding (VES) was carried out at Makurdi, Benue State Capital which is in the North Central of Nigeria using Schlumberger electrode array. The results show that the area is characterized by 4–5 geoelectric subsurface layers. The measured aquifer thickness ranges from 6 to 69 m, with an average value of 36.7 m and the aquifer resistivity ranges from 7 to 378 Ωm with an average of 133.8 Ωm. The aquifer thickness and aquifer resistivity were used to compute the values of the hydraulic conductivity and transmissivity. The aquifer thickness and aquifer resistivity along side with the estimated hydraulic conductivity and Transmissivity were used as indices for evaluation of groundwater potentials. The groundwater productivity potential in the area has been classified into two zones namely; high and intermediate. This study has revealed that no single index determines the groundwater productivity potential but a combination of two or more factors.
Keywords: Vertical electrical sounding, groundwater potentials, aquifer resistivity, hydraulic conductivity transmissivity and Makurdi.