应力场演化与强震间相互作用的有限元模拟研究  

Study on the Stress Evolution and Finite Element Model for the Interaction Among Strong Earthquakes

作　　者：王建国[1] 董洪军[1] 陈化然[1] 陈连旺[2] 马宏生[3] 

机构地区：[1]天津市地震局,天津300201 [2]中国地震局地壳应力研究所,北京100085 [3]中国地震局地震预测研究所,北京100036

出　　处：《国际地震动态》2006年第12期24-30,共7页Recent Developments in World Seismology

摘　　要：针对川滇地区,在大量搜集前人资料和结果的基础上,建立了包括上地壳、中地壳、下地壳、上地幔等4层结构的三维有限元模型。通过反复调试,确定了其边界条件。然后计算了川滇地区背景应力场、断层蠕动产生的应力场和强震触发的应力场,以及它们的动态变化。结果表明后续地震大多发生在前面地震引发的库仑破裂应力正值区,前一地震对后续地震有一定的触发作用,强震是在较高的应力背景下成组发生的。这对判断、识别地震异常,提高地震预测水平有着很大的意义。Based on the research on the group preparation and activities of strong earthquakes and quasi-3D finite element method, the quasi-3D finite element model for Southwest China has been established. Then, a 3D finite-element model containing four layers of upper crust, lower crust （two layers） and upper mantle is established in the paper. By repeated tests and revisions,, the boundary conditions of the model are determined. And then the background stress field, the stress field caused by fault creep and the stress field triggered by strong earthquake in Sichuan-Yunnan region, as well as their dynamic variations are calculated. The results indicate that the latter earthquake often occurs in the area with positive Coulomb rupture stress associated with the former one, the former earthquake has a triggering effect on the latter one to a certain extent, and strong earthquake often occurs in groups under the background of high stress, which is of great significance for distinguishing seismic anomalies, as well as for improving the level of earthquake prediction.

关 键 词：三维有限元模型 背景应力场 强震触发应力场 

分 类 号：P315.8[天文地球—地震学]