近断层强地震动预测中的有限断层震源模型

提出了近断层强地震动预测中建立活断层上设定地震有限断层震源模型的方法和步骤.首先,根据地震地质和地震活动性调查以及地球物理勘探等资料,确定活断层的空间方位和滑动类型;然后,根据地震定标律确定活断层的宏观震源参数;第三,将高强体模型与k平方滑动模型相结合,产生断层破裂面上的混合滑动分布.在此基础上,预测了与1994年Northridge地震断层类型、矩震级(Mw6.7)基本一致的设定地震的有限断层震源模型.最后,将预测的有限断层震源模型与基于地震学的、使用动力学拐角频率的地震动随机合成方法相结合,预测了1994年Northridge地震近断层12个基岩台站的加速度时程,并和实际记录进行了对比. 结果表明,用上述方法和步骤建立的有限断层震源模型是可行、实用的.

Finite Fault Source Model for Predicting Near-Fault Strong Ground Motion

A new method and steps of setting up a finite fault source model of a scenario earthquake on an active fault for predicting near-fault strong ground motion are proposed here.Firstly,spatial orientation and slip type of the active fault are deduced from data of seismic geology,seismicity,and geophysics exploration and so on.Secondly,macro-source parameters of the active fault are inferred from seismic scaling laws.Thirdly,the hybrid slip model on the fault plane is generated by combining the asperity model with k square slip model.On the basis of the above mentioned,the finite fault source model of a scenario earthquake(its fault type and moment magnitude the same as 1994 Northridge earthquake's,i.e.,the reverse fault and Mw6.7) is predicted consequently.Lastly,combining the finite fault source model predicted by mentioned-above with stochastic method of synthesizing ground motion using dynamic corner frequency based on seismology,we predict acceleration time histories of the 12 stations during 1994 Northridge earthquake.And comparison between predicted and recorded acceleration time histories shows that the above-mentioned method and the steps of modeling finite fault source model are feasible and practicable.