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地震活动的断层系统有可能处于自组织临界(SOC)状态。对简单的自组织临界模型的研究说明,地震从本质上讲也许是不可预测的.本文中,我们使用更复杂、更切合实际的自组织临界模型分析了地震的可预测性问题。这个模型是由具有暂态蠕变特性的弹簧一滑块系统构成的。该模型除了能够再现地震大小的幂律分布外,还可再现前震和余震序列。所模拟的地震序列还表明,除了大地震之前在短临阶段地震活动性的迅速增强外,平均来说这些事件发生在中期时间尺度的地震活动性降低之后.这个时期的地震活动性降低越明显和持续时间越长,后续的主震震级也就越大。我们发现,地震活动平静期的检测有助于改进与时间无关的危险性评估工作。这种改进对最大目标地震的危险性估计最重要。
Seismic fault systems are likely to be in a self-organized critical (SOC) state. Studies of simple self-organized critical models suggest that earthquakes may be inherently unpredictable.In this paper, we use a more complex and realistic self-organizing critical model to analyze the predictability of earthquakes. This model consists of a spring-slider system with transient creep properties. In addition to reproducing the power-law distribution of the earthquake size, the model can also reproduce the foreshock and aftershock sequences. The simulated earthquake sequence also shows that on average these events occurred after the reduction of seismicity on the mid-term time scale, except for the rapid increase of seismicity in the short and immediate phases before the major earthquakes. The more obvious the decrease of seismicity during this period And the longer the duration, the greater the magnitude of the following mainshock. We found that the detection of seismic quiescence helps to improve the time-independent risk assessment. This improvement is most important for the risk assessment of the largest target earthquake.