IJSR - International Journal of Scientific Research

Dr. K. Krishnakumar; Dr.B.Linda Prabhakar Babu

Volume : VII, Issue : V, May - 2018

Evaluation and Mapping of the Groundwater Potential Zones by using Electric Resistivity Survey of Dindi Reservoir Catchment Area Granitic Terrain of Mahbubnager and Nalgonda Districts of Telangana State, India

Dr. K. Krishnakumar, Dr. B. Linda Prabhakar Babu

Abstract :

43 vertical electrical soundings (VES) were carried out at selected locations in the study area in order to infer the potentiality of the groundwater in the subsurface. About 43 VES were carried out using a NGRI make D.C Resistivity meter wherein the current and potential readings are displayed for calculating the resistance. The interpretation of the resistivity data shows that the resistivity of the top layer generally varies from 10.56 Ohm–m to 30.0 Ohm–m. The thickness of the top layer extends up to 2 meters depth, followed by weathered zone varying from 30 Ohm–m to 50 Ohm–m up to 40 meters depth; resistivity of highly fractured zone varies from 60 Ohm–120 Ohm–m and was identified between 60 to 80 meters followed by hard granite. The pseudo cross sectional profiles revealed that at VES 39 aquifer can be encounter at the depth of 51.8 meters which shows the low resistivity values, at VES 26, the depth of the aquifer might be 23.7 meter, at VES 23, VES2, VES 18, VES7 groundwater potential zones could be encounter at 26.8 meters depth. At VES3, VES5 and VES 42 secondary porosity is occurred at 19.3 meters and 13.3 meters depth respectively. Weather to highly weathered rock at shallow depths i.e. up to 10 meters depth followed by hard granitic formation available at VES numbers via, VES32, VES40, VES37, VES6, VES15, VES20, VES29 and VES14. Hard mantle with high resistivity values were observed at VES31, VES11 and VES 28.