自转速率快速变化引起的全球位移场和应力场  

Global Displacement and Stress Fields Induced by Fast Change of Earth′s Angular Velocity

作　　者：陈绍林[1] 张怀[1] 朱桂芝[1,2] 石耀霖[1] 

机构地区：[1]中国科学院研究生院计算地球动力学重点实验室,北京100049 [2]中国地震局第二监测中心,陕西西安710054

出　　处：《地震》2008年第4期1-12,共12页Earthquake

基　　金：国家科学自然基金(40774049,40474038);中国科学院知识创新工程重要方向项目(kzcx2-yw-123)联合资助

摘　　要：该文建立了百万网格的分层PREM地球模型,利用并行有限元方法计算了自转速率快速变化所引起的全球附加的位移场和应力场。计算模型中不仅考虑了地球的径向分层,同时还考虑椭率和地形的影响。利用数值试验的方法,系统分析了地球自转速率变化为Δω/ω=2×10-10时所引起的全球应力分布特征,研究表明椭率对地表各个应力分量的影响在千分之几,而地形的影响则表现为径向应力与地形正相关,且相同高度的地形在低纬度影响较大,纬向和经向的应力大小分别与地形在SN向和EW向的地形梯度直接相关。This paper constructed a layered earth model based on PREM,with more than one million meshes.The displacement and stress fields induced by the fast change of earth＇s angular velocity were also computed using parallel finite element method.In this model,the lateral heterogeneity was taken into consideration,and the topography data and ellipticity of the earth were also integrated in this model to simulate a more realistic earth.The characteristics of the displacement and stress distribution were systematically analyzed,with the assumption that the fast angular velocity change is Δω/ω=2×10-10 per year.

关 键 词：地球自转 横向不均匀性 全球网格模型 并行有限元计算 

分 类 号：P315.7[天文地球—地震学]