Non-Volcanic Seismic Tremor, Phase-Locking, and The Global Clustering of Great Earthquakes

Charles G. Sammis, & Stewart W. Smith

In Preparation 2012, SCEC Contribution #1640

A system of non-linear coupled relaxation oscillators is used to show how the communication between large earthquakes on a global scale can align their seismic cycles to produce a world-wide clustering of large events. Our model builds on recent observations that the seismic waves from a large earthquake can trigger an episode of non-volcanic tremor at the base of a distant fault. We assume that tremor is indicative of creep on the ductile extension of the fault zone that loads its overlying seismogenic layer thus advancing its clock toward failure. If this advance is larger toward the end of the seismic cycle, we show that the faults will align their cycles. We show that such phase locking is possible even if the recurrence intervals are not identical and that the phenomenon can align the cycles of multiple faults.

Citation
Sammis, C. G., & Smith, S. W. (2012). Non-Volcanic Seismic Tremor, Phase-Locking, and The Global Clustering of Great Earthquakes. Geophysical Research Letters, (in preparation).