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以川滇地区地壳运动GPS观测、地壳上地幔结构模型、地震精确定位、构造应力场、断层滑动速率和岩石圈流变特性等观测和研究结果为约束,采用多组不同尺寸的摩擦接触单元表示断裂带,建立包含安宁河-则木河-小江断裂带的三维有限元模型,并考虑了1327年以来断裂带上强烈地震活动对研究区域构造应力状态的影响,对断裂带上强震活动的主要控制因素,未来可能的强震危险区分布和构造应力状态的关系进行模拟实验研究.研究结果表明,青藏高原重力位能的影响、相邻块体相互作用是该断裂带系统构造应力分布特征的主要动力学控制因.模拟给出的断裂带应力分布与断裂带上现今b值图像等地震活动参数有一定的对应关系;但同时也发现断裂带上部分异常低b值区落在模拟实验中历史强震活动产生的应力低值区,这种矛盾的对应关系可能受历史强震释放应变能等多方面因素所影响.
Based on the observation and research results of GPS observations of crustal movement in the Sichuan-Yunnan region, the crust and upper mantle structure model, the precise location of earthquakes, the tectonic stress field, the fault slip rate and the rheological properties of lithosphere, multi-groups of friction contact elements Fault zone, a three-dimensional finite element model including the Anninghe-Zemuhe-Xiaojiang fault zone is established, and the influence of strong seismic activity on the fault zone to the tectonic stress state of the study area since 1327 is considered. Main controlling factors and possible future distribution of strong earthquake danger zones and tectonic stress state.The results show that the influence of gravitational potential energy on the Tibetan Plateau and the interaction between adjacent blocks are the tectonic stress distribution characteristics of the fault system The main dynamic control factor is given.The stress distribution in the fault zone given by the simulation has certain relationship with the seismic activity parameters such as today’s b-value images in the fault zone, but it is also found that the abnormally low b value zone in the fault zone falls in the simulation experiment In the history of low-stress areas generated by strong earthquake activity, this contradiction may be related to the strong earthquake release strain energy The influence of various factors.