邯郸地区主要断裂库仑破裂应力模拟与地震危险性分析  

Coulomb Fracture Stress Simulation and Seismic Hazard Analysis of Major Faults in Handan Area

作　　者：茅远哲 吕国军[1] 孟立朋[1] MAO Yuanzhe;Lü Guojun;MENG Lipeng(Hebei Earthquake Agency,262 Huaizhong Road,Shijiazhuang 050021,China;Hebei Key Laboratory of Earthquake Dynamics,465 Xueyuan Road,Sanhe 065201,China)

机构地区：[1]河北省地震局,石家庄市050021 [2]河北省地震动力学重点实验室,河北省三河市065201

出　　处：《大地测量与地球动力学》2021年第8期816-820,共5页Journal of Geodesy and Geodynamics

基　　金：河北省科技厅重点研发计划(18275404D)。

摘　　要：首先基于粘弹性有限元模型,结合邯郸地区活动断裂探测、历史强震数据及区内岩石圈介质分布,建立三维粘弹性有限元断层模型;然后代入运动学特征边界条件,模拟目标区活动断裂上发生地震引起的应力应变场变化;最后计算1830年磁县地震引起的周围断裂面和滑动方向上产生的库仑破裂应力变化,分析未来目标区强震危险性。根据实际地质情况和现今运动学条件模拟出的模型结果显示,磁县断裂上1830年磁县地震震中附近库仑应力减小,表明磁县断裂活动减小了1830年磁县地震震中附近的地震危险性;但在磁县断裂中、西段两端与2条北东向断裂(紫山西断裂和太行山山前断裂)交接处附近库仑应力有所加强,未来该地区的地震危险性值得关注。Based on the viscoelastic finite element model,combined with the active fault detection in Handan area and historical earthquake data and distribution of the lithosphere medium in the studied area,we construct a three dimensional viscoelastic finite element fault model.We substitute the kinematics characteristic boundary conditions into the model,and simulate the changes of stress and strain field caused by the earthquake on the active faults.Then,we caculate the Coulomb failure stress changes of the rupture surface caused by the 1830 Cixian earthquake and the sliding direction.At last,the risk of strong earthquake in the target area is analyzed.According to the simulation model based on actual geology and current kinematic conditions,the Coulomb stress near the epicenter of the original strong earthquake of the Cixian fault is reduced which indicates that the activity of the Cixian fault reduces seismic risk near the epicenter of the original strong earthquake.But Coulomb stress is strengthened near the junction of the middle and west sections of the Cixian fault and the two northeast trending faults(Zishanxi fault and Taihang mountain piedmont fault),and the seismic risk in the future should be monitored.

关 键 词：三维粘弹性有限元模拟 活动断裂 库仑破裂应力 地震危险性 

分 类 号：P313[天文地球—固体地球物理学] P315[天文地球—地球物理学]