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Abstract Synchronization behavior of large earthquakes (rupture of nearby faults close in time for many cycles) has been reported in many fault systems. The general idea is that the faults in the system have similar repeating intervals and are positively coupled through stress interaction. However, many details of such synchronization remain unknown. Here, we built a numerical model in the framework of rate‐and‐state friction to simulate earthquake cycles on the west Gofar fault, East Pacific Rise. Our model consists of two seismic patches separated by a barrier patch, which are constrained by seismic observations. We varied the parameters in the barrier to understand its role on earthquake synchronization. First, we found that when the barrier is relatively weak, synchronization can be achieved by afterslip or post‐seismic creep in the barrier patch. Second, static stress transfer can lead to synchronization, opposite to the suggestion by Scholz (2010,https://doi.org/10.1785/0120090309), which was based on results from a spring‐slider model using rate‐and‐state friction. Third, the width of the barrier is more important than its strength. When the barrier is narrow enough (no more than half the width of the seismic patch in our model), the system can achieve synchronization even with a very strong barrier. Fourth, for certain simulations, the interaction between the two seismic patches promotes partial rupture in the seismic patches and leads to complex behavior: the system switches from synchronized to unsynchronized over 10–20 cycles. 

Abstract Either the triggering of large earthquakes on a fault hosting aseismic slip or the triggering of slow slip events (SSE) by passing seismic waves involve seismological questions with important hazard implications. Just a few observations plausibly suggest that such interactions actually happen in nature. In this study we show that three recent devastating earthquakes in Mexico are likely related to SSEs, describing a cascade of events interacting with each other on a regional scale via quasi-static and/or dynamic perturbations across the states of Guerrero and Oaxaca. Such interaction seems to be conditioned by the transient memory of Earth materials subject to the “traumatic” stress produced by seismic waves of the great 2017 (Mw8.2) Tehuantepec earthquake, which strongly disturbed the SSE cycles over a 650 km long segment of the subduction plate interface. Our results imply that seismic hazard in large populated areas is a short-term evolving function of seismotectonic processes that are often observable. 

ABSTRACT Oceanic transform faults are a significant component of the global plate boundary system and are well known for generating fewer and smaller earthquakes than expected. Detailed studies at a handful of sites support the hypothesis that an abundance of creeping segments is responsible for most of the observed deficiency of earthquakes on those faults. We test this hypothesis on a global scale. We relocate Mw ≥5 earthquakes on 138 oceanic transform faults around the world and identify creeping segments on these faults. We demonstrate that creeping segments occur on almost all oceanic transform faults, which could explain their deficiency of earthquakes. We also find that most of the creeping segments are not associated with any large-scale geological structure such as a fault step-over, indicating that along-strike variation of fault zone properties may be the main reason for their existence.