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大地震前观测到前震,以及认为前震具有特殊的性质使得它们能够同其他地震区别开来,所有这些增加了地震是可以预报的希望。所提出的异常属性包括:震级较大的前震相对于震级较小的前震占有比正常值更高的比例;以到主震的时间为参数,地震活动速率以幂律加速;将许多地震序列进行平均时,前震在空间上向主震迁移。使用南加利福尼亚的地震活动性数据,我们证明了这些性质以及其他性质都可由一简单模型得到,这一模型认为,不管前震、余震和主震,任何一个地震都能触发其他地震。我们发现前震的前兆性质同主震的大小无关。这意味着:由于根据过去的地震活动性并考虑触发的级联作用,地震活动速率是可以预报的,因此地震(无论大震还是小震)也是可以预报的。触发的级联作用很自然地产生了大范围、长时间的交互作用,这可以用来解释在非常大尺度范围内观测到的地震活动性相关现象。
The observation of foreshocks prior to a large earthquake and the special nature of the foreshocks make them distinguishable from other earthquakes, all of which add to the predictable promise of earthquakes. The proposed anomaly properties include the higher pre-earthquake magnitudes relative to the fraction of the magnitude pre-seismic occupying a higher proportion than normal; the acceleration of the seismic activity with power-law up to the time of the main shock; many seismic sequences On average, the foreshock spatially migrates to the main shock. Using the Southern California seismicity data, we demonstrate that these and other properties can be derived from a simple model that suggests that any earthquake can trigger other earthquakes regardless of foreshock, aftershock and mainshock. We find that the precursory nature of the foreshocks has nothing to do with the size of the main shock. This means that because of the predictable magnitude of seismic activity based on past seismicity and the triggering cascade, earthquakes (whether large or small) can also be predicted. Triggered cascades naturally produce large-scale, long-term interactions that can be used to explain seismic-activity-related phenomena observed over very large scales.