Combined Geospatial, Geophysical And Geochemical Studies On Coastal Aquifer At Muttom-Mandaikadu Area, Tamilnadu, India

Abstract

A study was conducted in the Muttom-Mandaikadu coastal region, which is among the profitable coastal sectors in Tamil Nadu, to find the groundwater potential as well as its quality by an integrated geophysical, geospatial, and geochemical approach. The GIS-based weighted overlay analysis was used to merge different thematic layers to create the groundwater potential zone map. The geophysical resistivity survey was performed in the study area at 26 stations by applying a Schlumberger vertical electrical sounding technique. The observed data were interpreted using one-dimensional software AGI Earth Imager. The combined vertical electrical sounding result and remote sensing thematic maps have exposed the potential zone of groundwater in the study area. From the inferred results, it was observed that 20.8% of the area has ample groundwater potential, and 7.7 % of the area has scanty groundwater potential. The saltwater intrusion zone has been predicted by validating aquifer resistivity with Dar-Zarrouck (D-Z) parameter. From the geophysical and geochemical interpreted results, it was found that aquifers in 34.6% of the study area are vulnerable to saline contamination. The 4-D model with integrated groundwater quantity and quality suggests that the study area's Western part falls under excellent to good groundwater potential zone and excellent water quality.