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用遗传算法反演了神户地震余震震源谱的低频平坦段的幅值、拐角频率和记录台站的场地效应。所有的记录都用传播路径上的品质因子Q作了校正,对于每一个余震假定不同的Ω~2模型,这样所有台站的低频平坦段幅值和拐角频率使得场地效应的标准偏羞减到最小。我们观察到岩石场地的场地效应在高频段显示出很大的放大作用。发现这种放大与位于70m深处的各个记录和一个地表台记录的频谱比相关。在估计了地震矩和应力降后,我们发现地震矩M_0与拐角频率f_0的关系遵循的定标律是M_0∞f_0~(-3)发现在断层带上和深处的凹凸体的周围应力降值最大。
The amplitude, corner frequency and field effect of the low frequency flat section of the source spectrum of Kobe earthquake aftershocks were inversed by genetic algorithm. All records are corrected by the quality factor Q on the propagation path. For each aftershock, different Ω ~ 2 models are assumed, so that the low-frequency flat amplitude and corner frequency of all stations reduce the standard deviation of the site effect to Min. We observe that the site effect at rock sites shows a large amplification at high frequencies. This magnification was found to correlate with the spectral ratios recorded for each record located at a depth of 70 m and a land surface. After estimating the seismic moment and stress drop, we find that the relationship between the seismic moment M_0 and the corner frequency f_0 follows the scaling law M_0∞f_0 ~ (-3). The stress drop around the asperity on and along the fault zone The largest value.