Dislocation creep flow laws of wet quartzite: the significance of pressure and slip systems

Western University, Canada (1); State Key Laboratory of Continental Dynamics, Department of Geology, Northwest University, Xi’an, China (2) An accurate flow law for dislocation creep of quartzite is critical for the understanding of continental rheology and geodynamic models. Despite many years of effort, existing creep experiments have yielded very different quartz flow law parameters. We demonstrate that the difference can be explained by considering the pressure effect on the activation enthalpy and the slip system dependence of the stress exponent. We carefully examine high-quality experimental data of wet quartzite corresponding to steady-state regimes 2, and 3 dislocation creep together with related quartz c-axis fabrics and identify two end-member quartz flow laws corresponding to dominant prism