RN-31 : Geophysical investigations for hydrological studies

Abstract

Geophysical investigations are effectively utilized in various hydrological applications. They provide fast and economic means of handling hydro-geological problems like exploration for groundwater, studies on movement and quality of groundwater, geothermal exploration, water balance studies of lakes and reservoirs, seepage losses from reservoirs and canals, etc.

Various geophysical methods have been classified as surface and sub-. surface methods. Surface methods include natural field methods (e.g. telluric, magneto-telluric and S.P.) as well as resistivity, electromagnetic, seismic(refraction and reflection), gravity, magnetic and nuclear methods. Latter class of methods includes borehole geophysical techniques comprising of S.P., resistivity, induction, induced polarisation etc. logging methods and selected nuclear methods.

After introducing different geophysical methods and their relevant details, general applications of these methods in hydrological studies have been reviewed. A comprehensive list of references is provided for detailed knowledge of various methods.