视应力在震后趋势判定中的应用——以前郭地震为例

Using Apparent Stress for Post-seismic Tendency Determination:Taking Qianguo Earthquake Sequence as An Example

选取前郭地震序列2013年10月31日至2014年4月30日期间发生的11个MS4.0以上地震的波形资料,计算了这11个地震的视应力。结果表明,3个MS5.0以上地震发生前,震源区相当震级地震的视应力和拐角频率在升高,这表明震源区应力水平在增强;在此之后,震源区地震的视应力和拐角频率在降低,据此及时地进行震后趋势判定。

We calculated the apparent stress of the 11 Ms≥4. 0 earthquakes in the Qianguo earthquake se-quence occurred from October 31, 2013 to April 30, 2014 using their seismic waveform data. The results indicate that the apparent stress and corner frequency of approximate magnitude earthquake in the source region increased before the occurrence of the 3 Ms≥5. 0 earthquakes. It means that the stress increased in the source region. Then the apparent stress and corner frequency of earthquake in the source region de-creased. We do the post seismic trend judgment upon the results.