Spectral element simulations of rupture dynamics along planar and kinked frictional faults

Understanding earthquake source dynamics is a major topic in seismology. Earthquake faulting is mainly controlled by non-regular friction, describing the dissipation within the fault interface, by the geometrical complexity of the fault and by the off-fault damage interactions. Recent observations during the Denali and Izmit earthquakes have shed evidence for supershear propagation in relation with the fault geometry. Numerical simulations of earthquake rupturing can bridge the gap between laboratory experiments and observations of large earthquakes. The simulations are expected to capture the different space and time scales involved in the nucleation phase, the rutpure front propagation and the short wave radiation, owing to the fault heterogeneities and geometrical complexities. Non-smooth spectral element method allows for efficient simulations of dynamic rupture along planar and non-planar faults. We present here recent numerical results on sub- and supershear propagation along bending and kinked faults. In particular, we focus the attention on the subshear-to-supershear transition and on the interaction between fault geometry and high-frequency radiation emitted by the fault.

This work is a part of the SPICE European Project