<Li> Cratonic province--Peninsular India </Li> <P> India has about 340 hot springs spread over the country . Of this, 62 are distributed along the northwest Himalaya, in the States of Jammu and Kashmir, Himachal Pradesh and Uttarakhand . They are found concentrated along a 30 - 50 - km wide thermal band mostly along the river valleys . Naga - Lusai and West Coast Provinces manifest a series of thermal springs . Andaman and Nicobar arc is the only place in India where volcanic activity, a continuation of the Indonesian geothermal fields, and can be good potential sites for geothermal energy . Cambay graben geothermal belt is 200 km long and 50 km wide with Tertiary sediments . Thermal springs have been reported from the belt although they are not of very high temperature and discharge . During oil and gas drilling in this area, in recent times, high subsurface temperature and thermal fluid have been reported in deep drill wells in depth ranges of 1.7 to 1.9 km . Steam blowout have also been reported in the drill holes in depth range of 1.5 to 3.4 km . The thermal springs in India's peninsular region are more related to the faults, which allow down circulation of meteoric water to considerable depths . The circulating water acquires heat from the normal thermal gradient in the area, and depending upon local condition, emerges out at suitable localities . The area includes Aravalli range, Son - Narmada - Tapti lineament, Godavari and Mahanadi valleys and South Cratonic Belts . </P> <P> In a December 2011 report, India identified six most promising geothermal sites for the development of geothermal energy . These are, in decreasing order of potential: </P> <Ul> <Li> Tattapani in Chhattisgarh </Li> <Li> Puga in Jammu & Kashmir </Li> <Li> Cambay Graben in Gujarat </Li> <Li> Manikaran in Himachal Pradesh </Li> <Li> Surajkund in Jharkhand </Li> <Li> Chhumathang in Jammu & Kashmir </Li> </Ul>

Which is the most important source of power generation in rajasthan