2016年7月19日新疆M_S 4.5级地震乌什地震台形变异常

Analysis on Seismic Anomalous of Deformation Caused by the Wushi M_S 4.5 Earthquake

利用乌什台数字化前兆形变观测资料,分析乌什MS 4.5级地震前乌什台水管倾斜仪、洞体应变仪数据变化情况。通过对比分析发现:地震前,洞体应变仪北南分量数据曲线正常,东西分量数据曲线加速拉张,05:14—20:32拉张幅度达到7.40×10^(-7),7月19日5时至20日16时乌什洞体应变仪东西分量快速拉张了9.20×10^(-7);7月19日5—19时,水管倾斜仪北南分量数据曲线正常,东西分量数据曲线反向西倾7.13ms,且05:59—06:06、07:36—07:46、18:42—18:56数据掉格,水管倾斜仪异常结束后1小时,在洞体应变仪异常过程中发生了乌什MS 4.5级地震。水管仪东西分量震前反向西倾,洞体应变仪东西分量震前拉张加速,短临异常明显,且2套形变观测震前异常时间同步性较好。

We used Wushi digital precursory deformation observational data to analyze the water tube-tilt and cave strain changes before the Wushi Ms 4.5 earthquake. Through comparative analysis we found that before the Wushi Ms 4.5 earthquake, the north-south strain component recorded in the Wushi cave instrument is normal, but the east-west component value changes greatly. The amplitude of stretching is 7.40×10-7 from 05：14 to 20：32. From 05：00 to 19：00 on July 19, the east-west component records from the Wushi water-pipe tilt meter is normal and the east-west component value is reverse to westward inclination 7.13ms. Moreover, the recorded data drop out at 05：59 -06： 06, 07： 36-07： 46, and 18： 42-18： 56. The water pipe inclinometer abnormal was observed after 1 hour, in the process of the body strain gauge anomaly Wushi Ms 4.5 earthquake occurred. The EW component of water tube-tilt from Wushi station west-dipping reverse, cave stuff strain tensile EW component rapid tension before the earthquake, short-impending anomalies before the seismogenic, and the two sets of deformation observation of seismic anomalous have a good agreement to each other.