Application of Electrical Resistivity Tomography in Delineation of Saltwater and Freshwater Transition Zone: A Case Study in West Coast of Maharashtra, India
The high levels of salinity have provided a unique opportunity with which to utilize geoelectrical characterization methods such as electrical resistivity imaging (ERI). Electrical resistivity surveys have been used for many decades in hydrogeological, mining, geotechnical, environmental, and even hydrocarbon exploration. There are, therefore, an increasing number of users for the ERI technique in India and abroad for mapping the accurate location of subsurface geological formations and structures such as faults, fractures, joints for delineation of water-bearing zones, geothermal. Of all nonintrusive surface geophysical techniques, the electrical resistivity profiling and vertical electrical sounding methods have been applied most widely to detect and monitor saline water/freshwater transitions in different coastal areas in the last several years with proven efficiency. Water resources in coastal regions of Maharashtra, India assume a special significance because of rapid strides in developmental activities thereby depleting the available groundwater.