Research on distinguishing method and mechanism of tidal deformation anomalies before large earthquakes  

作　　者：张晶 陈荣华 杨林章 吉平 

机构地区：[1]Institute of Earthquake Science, China Earthquake Administration,Beijing 100036, China [2]China Earthquake Network Center, China Earthquake Administration,Beijing 100036, China

出　　处：《Acta Seismologica Sinica(English Edition)》2006年第2期155-162,共8页

基　　金：Joint Seismological Science Foundation of China (106013).

摘　　要：By analyzing the digital tilt tidal observations at Yongsheng station and strain tidal observations at Houma station, this paper suggests that the solid tidal force might trigger tiny abrupt deformation when the seismogenic system enters into an instable critical state. The step and abrupt changes correlate to a certain extent to the direction of tidal force and the orientation and size of tidal shear stress along the fault strike. In the paper, we study for the first time the relationship between deformation anomaly and additional tidal stress in order to approach the physical mechanism of anomalies appeared immediately before earthquakes and the distinguishing method.By analyzing the digital tilt tidal observations at Yongsheng station and strain tidal observations at Houma station, this paper suggests that the solid tidal force might trigger tiny abrupt deformation when the seismogenic system enters into an instable critical state. The step and abrupt changes correlate to a certain extent to the direction of tidal force and the orientation and size of tidal shear stress along the fault strike. In the paper, we study for the first time the relationship between deformation anomaly and additional tidal stress in order to approach the physical mechanism of anomalies appeared immediately before earthquakes and the distinguishing method.

关 键 词：tidal force TRIGGER deformation anomaly 

分 类 号：P315.2[天文地球—地震学]