【摘要】 2010-04-14我国青海玉树附近发生Mw 6.9级地震。具体研究了该地震的前震-主震-余震序列应力触发模式及主震对周边断层的应力扰动。结果表明,大部分余震分布在同震库仑应力正区且余震触发率达76.4%;Mw 4.9级前震对Mw 6.9级主震的触发作用不甚明显,而后者对Mw 6.1级余震有明显触发作用;甘孜-玉树断层几乎都处于同震库仑应力加载状态,该断层上的历史破裂段如1738年M7.5级地震的当江段、哈秀段以及1896年M 7.3级地震的邓柯段未来更倾向于再次错动,造成强烈地震。更多还原

【Abstract】 We here investigate the coseismic Coulomb stress change and seismicity rate induced by the 2010 Mw 6.9 Yushu earthquake in order to deepen our understanding of the behavior of stress triggering among its foreshock,mainshock and aftershocks and to further make an assessment of the occurrence of potential earthquakes in its surrounding region and on major active faults.Our results show that: 1) the pattern of aftershocks of the Mw 6.9 Yushu earthquake is consistent with the spatial distribution of coseismic Coulomb stress changes with an aftershock triggering rate of 76.47%;2)For this 2010 Yushu earthquake sequence of foreshock-mainshock-aftershock type,the Mw 4.9 foreshock has little contribution to the occurrence of the Mw 6.9 Yushu mainshock,whilst the triggering causality between the Mw 6.9 Yushu mainshock and the Mw 6.1 aftershock is well pronounced;3) the Coseismic Coulomb stress changes are loaded on the portions of Ganzi-Yushu fault such as the Dangjiang and Haxiu segments which have been ruptured by the 1738 M 7.5 earthquake and the Dengke segment of the 1896 M 7.3 earthquake as well as the southeastern unruptured extension from the end of the Mw 6.9 earthquake termination,and thus they all pose high earthquake hazards in the near future.更多还原