利用重复地震观测重庆巫山地区地壳介质变化

利用波形互相关技术，对重庆数字地震台网记录的巫山地区90次地震波形资料进行相关计算，识别出24对同时被2个地震台站记录且各台波形互相关系数不小于0.8的重复地震对；利用射线追踪方法，对巫山地区重复地震位置做归一化处理，得到所选台站记录地震P波走时差变化，结果显示，在2013年重庆巫山M_L 3.7地震前，建坪、双龙、荆竹地震台记录到该地区短期地壳介质速度有明显升高现象。

Monitoring crustal media variation in Wushan area of Chongqing Municipality by using repeated earthquakes

Based on the 90 earthquakes recorded in Wushan area recorded by the Chongqing Digital Seismic Network, the correlation calculation of the seismic waveform data was carried out using the waveform cross-correlation technique. It was identified 24 earthquake doubles with waveform correlation coefficient was not less than 0.8 and recorded by 2 stations; The position of repeated earthquakes in Wushan area is normalized by ray tracing method, and the change of P-wave travel time difference of the selected stations is obtained. The results indicate the short-term velocity variation of crustal media appears before Wushan M_L 3.7 earthquake in 2013.