Electrical resistivity method applied to study groundwater resources in and around the zaheerabad town, Sangareddy District, Telangana, India

To investigate the subsurface geological and hydrological conditions around the area of the Zaheerabad Town, 16 vertical electrical soundings using Wenner array were performed to a maximum AB/2 spacing of 150 m. Quantitative and qualitative interpretations of data were carried out to determine the nature and thickness of the aquifer zone. The average resistivity in the topsoil is 33.37 Ωm with an average depth of 11.03 mts in the weathered zone the average value is 13.71 Ωm with an average depth of 30.83 mts in the semi weathered zone the average value is 34.04Ωm, with an average depth of 53.89 mts. Along this zone three bore points went dry at Hoti-B village as these points had shallow weathered zone of about 19 meters average and later was the massive basalt without any Intertrapean bed and no proximity to lineaments. Apart from Hoti-B two points at Algole village did not yield proper water as this too had little weathered zone and is within massive basalt devoid of proper recharge conditions and lack of Intertrapean bed. The basic controlling point in the region which has been observed from the geophysical survey and the study of the litho-log at the time of drilling indicate that where ever good weathered zone with proper depth and the ash bed/Intertrapean/tuff beds were encountered, there was good yield in the wells and the failure cases has only massive basalt or the clay formation. This study has revealed for this area, an average depth of the aquifer of 32 m with the average thickness of the aquifer being 22 m. The geoelectric sections of some VES stations demarcated corroborate very well with the geological description of the area.