Summary and Conclusion

Abstract

Thermal springs are considered to be natural phenomena expressing earth’s internal energy i.e. geothermal energy in the form of hot water, sub-surface steam and associated minerals and gases. They are variously named such as hot springs, mineral springs, geysers, fumaroles etc based on their nature, characters and mode of manifestation. Geothermal energy is manifested in form of thermal springs at eight places in Odisha. They are mainly confined to crystalline schists and gneissic terrains of Precambrian period and emerge more or less along a line, which indicates a lineament, fault or fissure, through which heated water from deep regions comes to the surface. The thermal springs of Odisha are pigeonholed under two categories of geothermal environment namely Mahanadi Valley geothermal province and Pre-Cambrian geothermal province. The temperatures of these thermal springs vary from 32°C to 67°C. They are mildly alkaline in nature and the rate of discharge of thermal water varies from 33 lpm to 84 lpm. The high temperature springs are characterized by steam and gas ebullitions. Most of the springs are noted with sulphurous smell. Chemically the springs can be grouped into two types namely (i) NaCl type and (ii) NaHCO₃ type except Boden thermal spring which is CaHCO₃ type. The total dissolved solids contents reveal that they are low in mineral content. The thermal spring gases of Odisha are nitrogen dominant type having very high nitrogen, low oxygen and traces of methane, argon etc. Rare gas helium is associated with Attri, Taptapani and Deuljhori thermal springs. The physico-chemical characters suggest that the thermal springs of Odisha are of meteoric origin. Geothermal energy scene is changing very fast with a rapid spurt in its direct and indirect use, primarily due to eco-friendly, renewable and pollution free character. Exploration and exploitation of this energy can open up new vistas in the direction of future energy requirement.