IS THE INDIAN SHIELD HOTTER THAN OTHER GONDWANA SHIELDS

Geothermal data on various Precambrian terrains from the African, Australian, Indian and South American (Brazil only) Gondwana landmasses have been compiled, synthesised and statistically analysed. The results do not support the prevailing notion that the Indian Shield is hotter than other shields. The study clearly shows that the mean surface heat flow values from the various Precambrian cratons and mobile belts of the Indian landmass for which the data have become available are either equal to, or even lower in some cases, than that in similar terrains from other Gondwana continents. Further, on the basis of available data, it is found that the Moho and the reduced heat flow values and Moho temperatures in the South Indian, South African, Western Australian and Brazilian shields fall within a narrow range, thus indicating, within the error limits of the estimation, the similarity of these shields in terms of these characteristics. In conclusion it is shown that the Indian landmass is not hotter than the other Gondwana landmasses, including even the presently immobile African continent, and that the ''super-mobility'' of the Indian landmass does not appear to be associated with its thermal characteristics. The cause of the latter lies elsewhere.