Influence of self-similar stresses on scenario earthquake construction:An example along the Tanlu Fault  

作　　者：Feng HU Huajian YAO Houyun YU Zeyu LU Jieyi HOU Song LUO Zhigang SHAO Xiaofei CHEN 

机构地区：[1]School of Earth and Space Sciences,University of Science and Technology of China,Hefei 230026,China [2]Mengcheng Geophysical National Field Scientific Observatory,Hefei 230026,China [3]Department of Earth and Space Science,Southern University of Science and Technology,Shenzhen 518055,China [4]Institute of Earthquake Prediction,China Earthquake Administration,Beijing 100036,China

出　　处：《Science China Earth Sciences》2024年第5期1687-1697,共11页中国科学（地球科学英文版）

基　　金：supported by the National Natural Science Foundation of China(Grant Nos.42125401,42074049);the Anhui Provincial Key Research and Development Program(Grant No.202104a07020016);the University of Science and Technology of China(USTC)Research Funds of the Double First-Class Initiative(Grant No.YD2080000059);the Youth Innovation Promotion Association of the Chinese Academy of Sciences(Grant No.2023471);the Joint Open Fund of Mengcheng National Geophysical Observatory(Grant No.MENGO-202101)。

摘　　要：As a famous deep and large fault in eastern China,the Tanlu Fault passes through Anhui,Jiangsu,and Shandong and into northeastern China.It is important to improve the understanding of seismic hazard assessments in areas near faults.We start a scenario earthquake simulation in the M7.5 earthquake potential area of the Xinyi-Sihong segment of the Tanlu Fault.The fault rupture length and width are constrained according to the scaling law of large intraplate earthquakes,the background normal stress is depth dependent,and the initial shear stresses are determined using trial and error by matching the earthquake magnitude.Considering the 120 km rupture length of the M7.5 earthquake,we compare the horizontal uniform stress model and self-similar stress perturbation model.Our findings reveal that the seismic source time function of the horizontal uniform stress model is similar to that of the Haskell model and that of the self-similar stress perturbation model is more similar to that of a real earthquake case.We compare the dynamic rupture simulation and ground motion results under four different stress conditions and find that the shorter the characteristic length of the self-similar function is,the rougher the initial stress.For the M7.5earthquake with an epicenter in the vicinity of Suqian,the Xinyi-Tancheng segment,which is located in the IX-intensity zone north of the epicenter,vibrates more strongly on the northern side than on the southern side due to the influence of the lowvelocity zone and the peak slip rate.The response spectra analysis at stations in the study area is useful for improving the earthquake resistance capability.

关 键 词：Scenario earthquakes Self-similar stress Tanlu Fault Dynamic rupture Ground motion 

分 类 号：P315.2[天文地球—地震学] P542.3[天文地球—固体地球物理学]