Insights into the kinetics of solid gypsum dehydration from wide and small-angle synchrotron X-ray scattering

Fluids liberated through the dehydration of hydrous minerals play a major role during earthquake formation, volcanism, metasomatism, and metamorphism in the lithosphere. The kinetics of the dehydration of natural gypsum rock are studied here with novel in-situ dehydration experiments using synchrotron transmission X-ray scattering. Powdered materials are used most commonly when studying dehydration kinetics of gypsum and other minerals. The presented experiments on natural rock highlight the physical importance of rock microstructure and grain-scale stresses in dehydration processes. This result has important implications for future experimental design and upscaling of kinetic data to understand crustal processes in real rocks