【摘要】 一次地震发生之后,地震烈度的迅速圈定对于总体灾情评估、地震应急响应和救灾物资调拨分配等均有重要意义.近年来随着地震科学的发展,强地面运动数值模拟已经成为定量化估计强地面运动的重要手段.在众多震源数值模型中,随机有限断层模型以其时效性和精确性成为烈度速报的首选模型.在本研究中,我们对原有的随机有限断层模型进行改进,实现了峰值加速度(PGA)、峰值速度(PGV)和峰值位移(PGD)的区域网格化计算,并且加入了浅层速度结构V30对模型模拟结果的影响.在2004Parkfield MW6.0地震、2008年汶川MW7.9地震以及1976年唐山MW7.6地震的实例应用中,数值模拟得到的烈度分布与野外调查烈度在整体分布特征、极震区烈度分布等方面均符合较好,该数值模型单个网格点的计算时间在0.3～0.5s左右,并且随着并行计算技术的引入计算耗时会进一步缩短.随机有限断层模型有效弥补了其他震源数值模型的不足之处,最大限度做到了快速且准确,可以作为烈度速报的一种数值模拟手段.更多还原

【Abstract】 Rapid regional MMI mapping soon after a moderate-large earthquake is crucial to loss estimation,emergency services and planning of emergency action by the government.In recent years,numerical simulation of strong ground motion has been well developed with the progress of earthquake science,and it has become an important means to estimate strong ground motion.In many of the models,stochastic finite fault model is preferred to rapid MMI estimating for its time-effectiveness and accuracy.In this research,we improve the original program EXSIM and the modified program named MEXSIM realizes regional computation of PGA(Peak Ground Acceleration),PGV(Peak Ground Velocity) and PGD(Peak Ground Displacement) which are essential for MMI estimating.Also,we consider the impact of V30,and the result of the comparison between the simulation and the observed MMI for Parkfield MW 6.0 earthquake,Wenchuan MW 7.9 earthquake and Tangshan MW 7.6 earthquake is fairly well.The consumed time of computing process for single point is about 0.3~0.5 s econd now in CPU with 3.40 GHz,and the consumed time will further reduce with the application of parallel computing techniques.更多还原