中文摘要：

以鲜水河断裂带为研究区,首先验证了该断裂带上1893年以来M6.7以上地震的相互触发作用,然后采用更符合实际的分层黏弹介质模型研究强震震后黏滞松弛引起的库仑应力变化对后续地震的影响,并基于负位错理论计算鲜水河断裂带10个断层段的震间长期构造加载作用引起的断层上的应力积累.在此基础上,讨论同震、震后、震间效应引起的累积库仑应力变化与区域强震活动的关系,给出断层上库仑应力随时间的演化.结果表明,鲜水河断裂带上1893年以来发生的7次强震均在其前面一系列强震及构造应力加载的驱使下发生,同震、震后、震间三方面效应均引起了鲜水河断裂带不可忽略的库仑应力变化.对断层上的库仑应力状态的研究,可进一步为揭示地震的发生规律、找寻危险断层段提供线索.

英文摘要：

Taking Xianshuihe fault zone as the study area, initially, we verified the Coulomb stress triggering of earthquakes with M≥6.7 along the fault zone since 1893, then using a more realistic model of multi-layered viscoelastic media, we calculated the Coulomb stress changes caused by viscoelastic relaxation of previous strong earthquake. In addition, we calculated inter- seismic stress accumulation caused by the tectonic loading generated by plate motions, the inter- seismic stress accumulation is modeled by introducing ＂virtual negative displacements＂ along 10 major faults segments in the region under study. On this basis, we further discussed the Coulomb stress accumulation caused by the co-seismic, post-seismic, and inter-seismic effect and its relationship with the regional seismic activity, and then simulated the evolution of Coulomb failure stress changes with time along the fault. The result shows that the occurrence of all of seven strong events on Xianshuihe fault since 1893 was driven by a series of previous strong earthquakes and tectonic stress loading, and co-seismic dislocation, viscoelastic relaxation and inter-seismic tectonic loading significantly affect the stress state on the fault. The study of theCoulomb stress changes along the fault zone can provide clues to reveal the law of earthquakes occurrence and find the fault segment at risk.