Calculated phase equilibria involving chemical potentials to investigate the textural evolution of metamorphic rocks

Abstract

Evolving pressure-temperature conditions during metamorphism drive changes in the stable mineral assemblage, mineral proportions and mineral compositions in rocks. These changes are achieved via the diffusion of components between minerals, fluid and melt, the driving force for diffusion being the gradients in chemical potential of the components developed spatially within the rock. This study utilises recent developments in the software thermocalc to investigate quantitatively chemical potential relationships in rocks, with the phases involved being (solid) solutions. Phase diagrams with chemical potentials as axes are used to understand better the spatial rearrangement of components during..