节点文献
青海玉树M_S7.1地震发震过程的数值模拟
NUMERICAL MODELING FOR MECHANISM OF YUSHU M_S7. 1 EARTHQUAKE
【摘要】 根据玉树地区的地应力场、速度场和断层展布,对青海玉树2010年4月14日MS7.1级地震发震机理进行了数值模拟。将围岩看成弹性体,断层看成具有应变软化的弹塑性体,断层和围岩组成统一的地质介质系统。在地应力、孔隙压力及边界位移的作用下,应力逐渐积累,当达到断层摩擦破坏强度时,断层产生应变软化,断层突然滑动,能量突然释放,应力突然下降,形成地震。模拟结果表明:玉树7.1级地震是在印度板块向北推挤,青藏高原向东南侧向挤压,在玉树地区形成主压应力为北东80°方向的水平应力场,使甘孜-玉树断裂带产生左旋走滑错动形成的。计算结果给出了应力降、能量释放量、断层走滑错动量、地震复发周期、应力积累速度等重要参数,模拟结果与野外调查资料具有较好的一致性。
【Abstract】 In this paper,strain softening model is used to establish the modeling for Yushu MS7.1 earthquake.The results shows that Yushu MS7.1 earthquake occurred as a combination of northward compressing of the Indian Plate and southeastward compressing of the Qinghai-Tibet Plateau.The stress drop,energy release amount,the magnitude of dislocation of fault,and earthquake recurrence intervals are given by the modeling.The modeling results show a good match with the geologic survey in the field.
【Key words】 Yushu earthquake; earthquake modeling: strain-softening model; unsteady model of earthquake;
- 【文献出处】 地质力学学报 ,Journal of Geomechanics , 编辑部邮箱 ,2010年02期
- 【分类号】P315.01
- 【被引频次】8
- 【下载频次】118