Ultrahigh temperature metamorphism in the Eastern Ghats Belt, India: evidence from high Mg-Al granulites

Abstract

This paper is aimed at reviewing evidence for and ultrahigh temperature (≥95O°C) of metamorphism at lower crustal depths obtatned largely from higb Mg-Al granulites of the Eastern Ghats Belt, India over the last decade or so. Reaction textures in a large variety of high Mg-AI granulites having different bulk rock X_Mg, and having equilibrated under different oxygen fugacities, are interpreted in theoretically and experimentally constructed petrogenetic grids in relevant systems. Data, leading apparently to divergent conclusions, are re-interpreted in the light of new petrographic and experimental evidence. Possible reasons for the development of anomalous high thermal gradients over the stretch of the Belt are discussed.