地震学报2012，Vol.34Issue(2)：224-234,11.DOI:10.3969/j.issn.0253-3782.2012.02.009
汶川地震强地面运动模拟
Strong ground-motion simulation of the Wenchuan earthquake
摘要
Abstract
Theoretical seismology method based on deterministic source function is mainly used in the low frequency wave simulation, since it is hard to simulate high frequency component precisely. High frequency wave can be simulated with stochastic approach or using empirical green's function, but these technique does not work for low frequency. Based on the deterministic simulation method, we try to simulate the broadband frequency (0. 1-10 Hz) strong ground-motion by subdividing the slip distribution across the fault plane. This method is to discretize the fault in second order and decompose the rise time variation to increase the high frequency components in the source function, so as to avoid the dependence on the accuracy and richness of seismic records. We simulated ground motions of Wenchuan earthquake at 8 selected stations located near the fault. The results show an overall agreement on the peak acceleration and duration within ±50% tolerance between the simulated and observed accelerations. The simulated Fourier spectra have the components as high as 10 Hz. The simulated Fourier spectrum at the stations in Sichuan basin attenuate faster than the observed because the method did not consider site effect. The strong ground motion simulation should take all the source, propagation path and site effect into consideration. Result of this study indicates that this deterministic method of changing input source function can be applied to simulation of near-fault strong ground motion in broad frequency band.关键词
汶川地震/强地面运动模拟/高频地震动/震源时间函数Key words
Wenchuan earthquake/ strong ground motion simulation/ high frequency ground motion/ source function分类
天文与地球科学引用本文复制引用
常莹,周红,俞言祥..汶川地震强地面运动模拟[J].地震学报,2012,34(2):224-234,11.基金项目
国家自然科学基金(40874027,90715020和90915012)资助. （40874027,90715020和90915012）
