Minerals deformation at deep earth conditions from atomistic simulations C. R. MIRANDA, S.SCANDOLO The Abdus Salam International Centre for Theoretical Physics (ICTP), Trieste, Italy

A detailed knowledge of the rheological behavior of Earth materials at high temperature and pressure conditions is essential to understand the dynamics and structure of Earth's interior. At those conditions, laboratory experiments are still a challenge. On the other hand, atomistic simulations have recently proved to be a reliable source of information about the microscopic deformation mechanisms (elasticity, slip systems and dislocations, etc.) in various systems, including metals, covalent and ionic solids. In this work, we analyse the microscopic deformation of MgO and Iron at high temperature and pressure conditions using atomistic simulations. For this purpose, we have calculated the so called Generalized Stacking Fault Free energy surfaces (GSF) using interatomic potentials which mimic ab initio energies, forces and stress. In order to explore high temperature effects, the free energies have been calculated using constrained dynamics. Using the GSF in the framework of Peierls-Nabarro model, the properties of dislocation motion, dominant slip systems and associated stresses have been obtained for MgO and for Iron (work in progress) at Earth's interior conditions.