Evaluation of Heterogeneous Aquifers in Hard Rocks from Resistivity Sounding Data in Parts of Kalmeshwar Taluk of Nagpur District, India

Interpretation of vertical electrical sounding (VES) data coupled with the estimation of coefficient of anisotropy (λ) in parts of Kalmeshwar taluk, Nagpur district, Maharashtra, India has yielded vital information on the characteristics of subsurface basaltic aquifers. The coefficient of anisotropy estimated at 22 sites from VES data has shown variation between 1 and 1.87, which in turn reveals the anisotropic character of the basaltic aquifers. The estimated fracture porosity from the interpreted parameters and specific conductance of groundwater within the region varies from 0.007% to ∼2%, indicating different degrees of water saturation within the basaltic flows. The interpreted true resistivity ∼10-35 Ω.m corroborates well with the zones of high porosity and λ further substantiates the presence of exploitable groundwater resources within the region.