Synchronization of megathrust earthquakes to periodic slow slip events in a single-degree-of-freedom spring-slider model

Recently recognized slow slip events (SSEs) recurring in the deeper extensions of seismogenic zones along plate boundaries are drawing attention to their potential for triggering megathrust earthquakes that rupture the entire seismogenic zone. We describe how earthquakes simulated in a single-degree-of-freedom model are synchronized to the rhythm of imposed periodic SSEs. The time lag t(Q) from the one most recent SSE to a seismic event varies with system parameters and may take a broad range of eligible values between 0 and T(SSE) (SSE recurrence period). Earthquakes were found to synchronize with SSEs in various patterns depending on the proportion of SSE-driven loading within an SSE cycle, the recurrence period of the SSEs, and the duration of the SSEs, although synchronization itself remained a prevalent feature. Asynchrony was found only for long SSE durations.