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 

作者机构：School of Earth and Space SciencesUniversity of Science and Technology of ChinaHefei 230026China Mengcheng Geophysical National Field Scientific ObservatoryHefei 230026China Department of Earth and Space ScienceSouthern University of Science and TechnologyShenzhen 518055China Institute of Earthquake PredictionChina Earthquake AdministrationBeijing 100036China 

出 版 物：《Science China Earth Sciences》 (中国科学（地球科学英文版）)

年 卷 期：2024年第67卷第5期

页      面：1687-1697页

核心收录：

学科分类：070904[理学-构造地质学] 070801[理学-固体地球物理学] 0709[理学-地质学] 07[理学] 0708[理学-地球物理学] 

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)。 

主　　题：Scenario earthquakes Self-similar stress Tanlu Fault Dynamic rupture Ground motion 

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.