Geothermal Resources of India -SCOPE and Future Utilisation

Abstract

Geothermal resources discovered in India consist of warm/hot water systems. The main geothermal manifestations are distributed in four areas viz: (1) a continental collision zone: Himalayan region, (2) marginal depressions: Himalayan foredeep, (3) coastal areas and (4) Peninsular shield areas. Geochemical and geophysical surveys are indicative of high temperatures, high heat flows and low resistivity zones in Puga, Manikaran and the west coast geothermal areas. At shallow depths medium temperature waters and reversal of temperature are very common. The mountaineous terrain, negative temperature gradient at the bottom and presence of travertine deposits of borax and sulphur distributed at different sites indicate that the above geothermal areas under exploratory drilling are that of lateral outflows of geothermal fluids away from upflow centres. To the south of Puga valley, very low resistivity zones have been recently located but it is difficult to do exploratory drilling in this area due to unruly topographic conditions.