Electrical Resistivity Survey to Delineate Groundwater Potential Zones in Granitic Terrain, Nalgonda District, India

Article type: Research Article

Authors: Dhakate, Ratnakar | Negi, B.C. | Singh, V.S.

Affiliations: National Geophysical Research Institute Hyderabad – 500 007, India

Note: [] Corresponding author. E-mail: [email protected]

Abstract: Vertical Electrical Soundings (VES) with Schlumberger configuration were conducted in order to delineate groundwater potential aquifer zones in Wailpally watershed area, Nalgonda district, Andhra Pradesh, India. The entire area is underlain by granite and gneissic complex. Locating favourable groundwater zones in granitic terrain is a very difficult task, as the secondary features developed in hard rocks like faults, fractures, lineaments and dykes control the groundwater flow and movement. Therefore, there is always a need for locating and pinpointing the favourable location in hard rock areas. In order to assess groundwater potential zones, 59 vertical electrical soundings (VES) with 100 to 200 m current electrode separation were conducted in the watershed area. Interpreted VES data were correlated with the drilled borehole logs and used to generate iso-resistivity maps like top layer resistivity, depth to the bed rock and longitudinal unit conductance maps. Based on VES interpreted data groundwater potential maps have been prepared showing good, moderate and poor zones.

Keywords: Vertical electrical sounding (VES), groundwater potential, pinpointing

Journal: Asian Journal of Water, Environment and Pollution, vol. 5, no. 1, pp. 17-25, 2008