Estimation of Aquifer Parameters from Surfacial Resistivity Measurement in a Granitic Area in Tamil Nadu

This article aims to establish an empirical relationship among geoelectrical properties of aquifer and hydrogeological parameters to estimate its hydraulic properties, and reduce the processes of pumping test, which are costly and time consuming. A total of 19 Vertical Electrical Sounding (VES) data were collected using Schlumberger configuration in a granitic terrain in Tamil Nadu. The geographical parameters were analysed with IX1-D v.3 Interprex software. The pumping test conducted on nearby open wells was also used. A cross-correlation test was ascertained between hydraulic conductivity (K) and aquifer resistivity (ρ). It was found that hydraulic conductivity is best defined as an exponential function of aquifer resistivity. The field parameters, A = 20.235 and B = 0.012, of the function were optimized by using 'Solver', with the least SSQ (=7.82) and MARE (=0.816). It helped to estimate hydraulic parameters along with an empirical equation without pumping test data. The results emphasized the potential of surfacial resistivity survey in granitic area to determine aquifer properties where well information is not available.