2006年11月23日新疆乌苏5.1级地震及部分地震学前兆异常特征

介绍了2006年11月23日新疆乌苏5.1级地震的基本参数、震源机制解、地震序列特征、发震构造和局部构造应力场;分析了震前数字地震波参数的变化和部分地震学前兆异常特征。研究结果认为,乌苏5.1级地震是博罗科努-阿齐克库都克断裂发生右旋走滑错动所致。震前观察到震中附近P波初动半周期、P波与S波振幅比以及应力降的变化。震前震中附近曾出现4级地震集中分布、3级地震空区图像,震前6~9个月出现震群活动,震前2个月温泉地震窗异常。除上述异常外,乌苏5.1级地震前整体异常比例不高。

Wusu earthquake with M5.1 on Nov. 23, 2006 in Xinjiang and anomalous precursory characteristics of part seismology

In the paper,we introduced some basic parameters,the focal mechanism solution,the earthquake sequence characteristics,the earthquake-generating structure and the local structure stress field of Wusu earthquake with M5.1 on Nov.23,2006 in Xinjiang.We analyzed the change of the digital earthquake wave parameter and the anomalous precursory characteristics of the part seismology before the earthquake.Through studying,we proposed that Wusu earthquake with M5.1 occurred along Boluokenv-Aqikekuduke fault,and the fault movement was right-lateral strike-slip.Before the earthquake,we observed some anomalous change of the half-period first motion of the P wave,the amplitude ratio of the P wave and the S wave and higher change of stress drops of small earthquakes nearby the epicenter.There appeared concentrated distribution of earthquakes with M4 and gap of earthquakes with M3 around the epicenter before the earthquake.There also appeared the earthquake swarms activity 6~9 months before the 5.1 earthquake,and earthquake window anomaly of Wenquan 2 months before the earthquake.In addition to the above anomalies,Wusu 5.1 earthquake fore-abnormal ratio of the whole is not high.