Groundwater potential zone identification using geoelectrical survey: A case study from Medak district, Andhra Pradesh, India

A Geoelectrical resistivity survey using Vertical Electrical Soundings (VES) was carried out in Medak District, Andhra Pradesh, India, in order to assess the subsurface geology and groundwater potential zones. Twenty six vertical electrical soundings were recorded with Schlumberger electrode configuration with current electrode spacing (AB/2) half ranging from 1 to 150m. The field data has been primarily interpreted using curve matching and electrical imaging computer software IPI2WIN. The curves are prominently of A and H type indicating the presence of three layers followed by combination of curves AK, HA, KH, HK, AH indicating the four layer followed by combination of curves HAA, HAK, AKH, QHA, AAA indicating the presence of five layer sub-surface layers. Interpretations revels the number of subsurface layers, their thickness and their water bearing capacity within the study area. The best layer which acts as the good aquifer of Medak districts is the second layer which consist the fracture/weathered rock formations at the depth between 5 to 15 m.