基于应变能变化的芦山强震同震效应的数值模拟  

Numerical Simulation of the Co-seismic Effect Deduced from the Lushan Strong Earthquake:Insights from the Strain Energy Change

作　　者：李玉江[1,2] 陈连旺[1] 杨树新[1] 

机构地区：[1]中国地震局地壳应力研究所(地壳动力学重点实验室),北京100085 [2]中国地质大学(北京),北京100083

出　　处：《震灾防御技术》2013年第4期361-369,共9页Technology for Earthquake Disaster Prevention

基　　金：国家科技支撑项目(2012BAK19B03-6);中央公益性科研院所基本科研业务专项(ZDJ2012-09;ZDJ2010-12)共同资助

摘　　要：芦山地震发生后,川滇地区主要活动断裂的地震活动趋势变化值得关注。本文基于川滇地区的三维非线性有限元模型,利用地震矩张量反演的断层节面性质及震级与破裂长度、同震位错量的经验公式,从应变能积累/释放角度分析地震的发生对川滇地区主要断裂的同震加卸载效应。初步结果表明,在33条断裂段中,有17条表现为同震加载效应,15条表现为卸载效应,1条影响不明显。地震的发生造成马尔康断裂、岷江断裂加载效应较强。但需要注意的是,滇西、滇西南地区主要活动断裂表现出群体性的加载效应。After the Lushan earthquake, the tendency of seismic activity in Sichuan-Yunnan region in future is of great interest. In this paper, from the strain energy accumulation and release aspects, we employ three dimensional nonlinear finite element model to explore the co-seismic loading/unloading effect on surrounding fault that deduced from the Lushan earthquake, based on the fault nodal solution from the seismic moment tensor inversion and the empirical formula between magnitude and rupture length or co-seismic dislocation. The preliminary results show that the Lushan earthquake causes loading effect in seventeen of total thirty-three faults, especially in the Barkam and Mirijiang faults, and unloading effect in fifteen of them. However, we also found that the faults in western and northwestern Yunnan present loading effect simultaneously.

关 键 词：川滇地区 芦山地震 同震效应 数值模拟 

分 类 号：P315[天文地球—地震学]