High Moho temperature in the Indian shield

Abstract

Moho temperatures in the Indian shield region are estimated using step, exponential and power-law models of the depth variation of radiogenic heat, with temperature-dependent thermal conductivity. The Moho temperatures and heat flows are around 550-600°C and 0.8 HFU (33 mWm⁻²) in the southern part of the Indian shield and 850-900°C and 0.95 HFU (40 mWm⁻²) in its northern part. It is argued that such high temperatures and their lateral variations may contain signatures of Deccan Trap volcanism and Himalayan orogeny. The implications of the temperature estimates on some related crustal parameters viz., P_n¯wave velocity, Curie isotherm depth and melting point temperature at Moho depth, are also indicated.