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There are vast areas in southern Indian shield which are occupied by charncockites. Making them requires by heating deep crustal rocks by such temperatures which can initiate partial melting in presence of water rather than metamorphism. So one needs to suppress the activity of water, while raising the temperatures for initiation of charnockitization. This can be done by influx of hot carbon dioxide from mantle depths. Raising of temperatures can also be achieved by over thrust of crustal rocks increasing the thickness of radiogenic crust and then reducing to normal crustal depths. Both processes have been modelled (Ganguly etal, 1995, J Met Petrol, 13, 419, Singh and Ganguly, 2015,in: Modeling of magmatic and allied processes, Springer) and these developments will be discussed. A combination of both processes for the charnockitization is preferred by such modelling approach. |