Geological processes and their geochemical signatures

Fracrional ciystalUzarion Assimilation + AFC Magma mixing RTF processes. Liquid immiscibility 

Flow diagram showing the principal precedes which control the chemical composition of igneous rocks. 

Processes which control the chemical composition of metamorphic rocks 

The ingress and expulsion of water during metamorphism, chiefly as a consequence of hydration and dehydration reacdons, may give rise to changes in the chemical composidon of the parent rock as a consequence of pardcular elements becoming mobile in the fluid. These processes are controlled by the composidon of the fluid phase, its temperature and the rado of metamorphic fluid to the host rock. 

Chemical change in metamorphic rocks in the absence of a fluid phase is 

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