Multiple scales, multi-physics interactions and nonlinearities govern earthquake source processes, rendering the understanding of how faults slip a grand challenge of seismology. Earthquake fault zones are more complex, both geometrically and rheologically, than an idealized infinitely thin plane embedded in linear elastic material. Complex volumetric failure may lead to complexity in the nucleation process (e.g., instantaneous vs. cascading ), rupture styles (e.g., pulses or cracks, sub-Rayleigh vs. supershear), slip distribution and energy balance. A realistic understanding of co-seismic, post-seismic and interseismic slip across diffuse fault zones should account for multi-physics coupling, nonlinear visco-elasto-plastic rock rheologies, natural heterogeneities, etc. Furthermore, diffuse fault zones evolve as potentially hierarchical fault structure over space and time.

This session encourages contributions shedding light on, but not limited to, volumetric faulting processes across different scales in both space and time. We welcome interdisciplinary and focused contributions that explore observations, laboratory experiments, numerical modeling and theoretical studies.