Beyond Backslip: Improvement of Earthquake Simulators from New Hybrid Loading Conditions

A standard approach to loading earthquake simulators involving complex fault system geometries is the backslip method, by which fault‐slip rates are specified and stressing rates giving the specified slip rates are calculated and imposed on the system. This often results in singularities in stressing rate at fault boundaries, and unrealistic hypocenters of events associated with these singularities. We present a new generalized hybrid loading method that combines the ability to drive faults at desired slip rates while loading with more regularized stressing rates, allowing faults to slip in a more natural way. The resulting behavior shows improvement in the depth dependence of seismicity, the distribution of sizes of events, and the depth dependence of slip. We discuss as well the physical implications of the new type of loading.