Assessment of groundwater study using geophysical and geochemistry mapping in Thamirabarani sub-basin, Karunkulam area, Southern India

Groundwater exploration study has been carried out in Karunkulam area, Srivaikundam taluk, Thoothukudi district, Tamil Nadu, with the help of geophysical and geochemical characteristics. The study area was covered in the meta-sedimentary rock of quartzite, and the source rock of sandstone was delineated from the channel of the Thamirabarani River. Resistivity sounding square array, 2D electrical resistivity imaging technique and magneto-telluric method were used to identify the aquifer thickness and bedrock in quartzite terrain of the study area. An attempt has been made to use GIS spatial distribution map for irrigation suitability and livestock drinking purposes. The hydro-geochemical facies were used to analyze the cations and anions exchange process. It was also observed that the Ca 2+ - HCO 3 − was dominant in the low alkalinity in nature and the quality of groundwater represents the geochemical nature in aquifer media. The type of rock–water interaction with Mg 2+ -Na + -Ca 2+ -Cl − -HCO − 3 , Na + -Ca 2+ -Mg 2+ -Cl − and Na + -Mg 2+ -Ca 2+ -Cl − indicates the rock water interaction between the quartzite, gneissic and some granitic intrusion in the part of the area. Based on geophysical 2D imaging and magneto-telluric resistivity, inferred fracture quartzite zones were water-bearing formation in the study area. This primarily supports the hypothesis assumed at the beginning of the research in the study area.