摘要
设计一个具有摩擦状态 速率依从机制模拟大地震后区域触发地震的模型,该模型由一定数量表示地震成核断层的函数组成。大震对区域静应力场的影响由应力阶跃载荷表现,利用摩擦状态 速率依从的一维自由度弹簧滑块模型结果计算地震发生时间提前。结果表明,施加幅度为地震应力降几十分之一至百分之一的应力阶跃,可以引起地震发生速率的明显变化,该变化通过统计检验,与大地震后的区域触发地震活动相似。
A frictional state-velocity dependent model was designed to study regional seismicity triggered by big earthquakes, which consisted of a number of functions representing the seismic nucleation faults. The effect of regional stress caused by big events was presented by stress step load, and a one-dimension frictional state-velocity dependent model of free string-block was used to estimate the advanced occurring time of events. The results show that remarkable change of seismicity could be detected while a stress load with amplitude one to several percents of stress drop was added, which was similar to the regional seismicity triggered by a big event. Change of the seismicity was proved to be significant by statistical test.
引文
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