九寨沟MS7.0地震强地震动模拟及漳扎镇地震动强度预测

破坏性地震强度预测可用于工程领域抗震设防以及地震危险性分析评估，是防震减灾中一项很重要的基础工作.为了再现九寨沟地震的地震动强度，评估缺失强震记录的九寨章扎台站的地震动强度，本文用经验格林函数法对九寨沟地震进行了数值模拟.选取了震源周边地震动峰值加速度超过10 Gal的10个强震台站进行模拟.因未得到九寨沟地震的余震，初次尝试将汶川地震和定西地震的余震作为格林函数模拟九寨沟地震.模拟结果整体上可以反映各台站地震动的强度特征，尤其是地震动高频成份拟合较好.模拟值的地震动峰值加速度、时程数据、反应谱等与观测值拟合较好.预测结果显示漳扎镇的地震动峰值加速度值约为180~200 Gal.预测结果也表明在缺少大震的余震记录时，经验格林函数法使用其他大震的余震同样可以再现目标地震的强度特征.本研究也为经验格林函数方法在缺乏小震记录地区的使用积累了经验.最后总结了格林函数的选取标准，为经验格林函数方法来预测未来强震动特征积累了经验.

Simulation of ground motion by the 2017 Jiuzhaigou MS7.0 earthquake and estimation of ground motion intensity in the Zhangzha Town

The intensity prediction of destructive earthquakes can be used in seismic fortification and seismic risk analysis and evaluation in the engineering field, which is an important basic work in earthquake prevention and disaster reduction. In order to reproduce the seismic intensity of the 2017 Jiuzhaigou M_S7.0 earthquake and evaluate the seismic intensity of the Jiuzhaizhangzha station, which missed seismic records, the empirical Green function method was used to simulate this earthquake and evaluate the seismic intensity in the Zhangzha town. Ten strong ground motion stations at which peak ground accelerations exceed 10 Gal were selected for simulation. Because of lacking the aftershocks, the first attempt was made to simulate the Jiuzhaigou earthquake with regarding the aftershocks of the 2008 Wenchuan earthquake and Dingxi earthquake as a green function. The simulated results can reflect the intensity characteristics of ground motion of each station as a whole, especially the high frequency component of ground motion is fitted well. The prediction results shows that the ground acceleration, time history, response spectrum and so on of the synthetic values are fitted well with the observed values. The prediction results also show that the peak ground acceleration value of the ground motion in the Zhangzha town is about 180~200 Gal. These demonstrate that the empirical Green function method can reproduce the intensity characteristics of the target earthquake by using the aftershocks of other large earthquakes when lacking aftershock records of large earthquakes. This study has also accumulated experience for the use of the empirical Green function method in the case lacking of small earthquake records. Finally, the selection criteria of Green function are summarized. This work provides an experience of predicting the characteristics of strong ground motion using the empirical Green function method.