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据观测,大地震通常能触发邻近断层上其他大地震。造成诱发的库伦应力传递的量级估计为地震应力降的10-2～10-3。相对于地震的天然复发时间而言,地震应力降和触发延迟时间都非常短。这将需要这两个断层同时接近于它们地震周期的末期。古地震学数据表明,对于相同区域,以前的地震在多个断层破裂群集中发生,这些群集以长期静止期间分开。这两种观测结果说明在断层之间发生了同步。理论和观测表明,在具有正应力耦合并且固有滑移速度处于诱导阈值范围内时邻近断层之间可存在同步现象。在南冰岛地震带、内华达州中部地震带和加利福尼亚州东部剪切带,可识别出多个看起来是独立行动的同步化群集。这种特征即为锁相的三维等效物,将导致各断层的地震循环周期受特征性大地震的控制,对于沿给定断层的各段同步化,也是如此。重复发生的单个地震或地震群的破裂模式在二维或三维情况下均各不相同。这种系统状态展现了不具有严格重复性的同步现象的明显指示,可称之为模糊同步。
It has been observed that large earthquakes usually trigger other major earthquakes on nearby faults. The magnitude of the induced Coulomb stress transfer is estimated to be 10-2 to 10-3 for the seismic stress drop. Compared with the natural recurrence time of the earthquake, the seismic stress drop and the triggering delay time are very short. This will require both faults to be close to the end of their seismic cycle at the same time. Paleoseismic data show that for the same area, previous earthquakes occurred in multiple fault-ruptured clusters that were separated by long-term quiescence. These two observations show that synchronization has taken place between faults. Theories and observations show that there can be a synchronization phenomenon between adjacent faults when there is positive stress coupling and the intrinsic slip velocity is within the induced threshold range. In the South Iceland seismic zone, the Nevada Central Seismic Belt and the eastern California shear zone, several synchronized clusters appear to act independently. This feature is known as a phase-locked, three-dimensional equivalent which will result in the seismic cycle cycles of each fault being controlled by characteristic large earthquakes, as well as for the synchronization of sections along a given fault. The recurrence pattern of a single earthquake or earthquake group is different in two-dimensional or three-dimensional cases. This state of the system shows a clear indication of a synchronization phenomenon that is not strictly repetitive and can be called fuzzy synchronization.