用(DDA+FEM)方法数值模拟1975年海城、1999年岫岩地震发生的过程  

NUMERICAL SIMULATION FOR 1975 HAICHENG AND 1999 XIUYAN EARTHQUAKE PROCESSES BY DDA+FEM

作　　者：张瑞青[1] 魏富胜[1] 乔成斌[2] 林邦慧[1] 

机构地区：[1]中国地震局地球物理研究所,中国北京100081 [2]中国地震应急搜救中心,中国北京100039

出　　处：《地震学报》2005年第2期163-170,共8页Acta Seismologica Sinica

基　　金：国家自然科学基金项目(40174011);(40274029)资助.中国地震局地球物理研究所论著05AC1008.

摘　　要：用非连续变形分析方法(DDA+FEM), 数值模拟了华北地区各地块相互制约构造环境中发生的1975年海城地震及1999年岫岩地震的过程. 通过对岫岩前震及近期余震分布图象的研究, 以及前人对海城地震的研究, 提出了海城、岫岩地震发震构造块体模型. 数值模拟结果给出了两次地震释放的主应力变化、最大剪应力变化等值线图, 地震前后位移变化矢量图, 及发震断层滑移随时间的变化, 分别与相应地震的震源机制、宏观等震线、发震断层的走滑性质等的结果基本一致.In this paper, using discontinuous deformation analysis, we simulate numerically the processes of the 1975 Haicheng earthquake and the 1999 Xiuyan earthquake in the tectonic environment of North China where blocks restrict each other by DDA+FEM. Based on the research on the distribution of foreshocks and recent aftershocks of Xiuyan earthquake and the results from study of Haicheng earthquake, we present a tectonic block model of Haicheng and Xiuyan earthquakes. The results from numerical simulation include the variation of principal stress field released by these two earthquakes, contour patterns of maximum shear stress change, variation patterns of displacement vectors before and after the earthquakes and variation of the earthquake fault slip with time, which agree basically with the focal mechanisms, macroscopic isoseismal and horizontal displacement characters from observations.

关 键 词：非连续变形分析方法 数值模拟 地震破裂过程 

分 类 号：P315.8[天文地球—地震学]