Coseismic surface ruptures of MW7.8 and MW7.5 earthquakes occurred on February 6,2023,and seismic hazard assessment of the East Anatolian Fault Zone,Southeastern Türkiye  

作　　者：Peng LIANG Yueren XU Xiaocheng ZHOU Ying LI Qinjian TIAN Huiping ZHANG Zhikun REN Jingxing YU Chuanyou LI Zheng GONG Shiguang WANG Aixia DOU Zifa MA Junjie LI 

机构地区：[1]Key Laboratory of Earthquake Prediction,Institute of Earthquake Forecasting,China Earthquake Administration,Beijing 100036,China [2]China Earthquake Disaster Prevention Center,Beijing 100029,China [3]State Key Laboratory of Earthquake Dynamics,Institute of Geology,China Earthquake Administration,Beijing 100029,China [4]Institute of Geophysics,China Earthquake Administration,Beijing 100081,China

出　　处：《Science China Earth Sciences》2025年第2期611-625,共15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.42041006,42072248);the National Science and Technology Basic Resources Investigation Program of China(Grant No.2021FY10010405);the Basic Scientific Funding of the Institute of Geology,CEA(Grant No.IGCEA2302);the Basic Research Program of the Institute of Earthquake Forecasting,CEA(Grant Nos.CEAIEF20240402,CEAIEF20230602,2021IEF0104,CEAIEF20240302)。

摘　　要：On February 6,2023,southeastern Türkiye experienced a devastating earthquake doublet along the East Anatolian Fault(EAF),with moment magnitude(MW)values of 7.8 and 7.5.These strong earthquakes resulted in at least 50,000 deaths and severe economic losses.Systematic research on coseismic surface ruptures induced by these events is vital for assessing the cascade rupture behaviors of plate boundary faults and future seismic hazards in the region.Interpretation of high-resolution post-earthquake satellite images and field investigations yielded the following results:(1)the two strong earthquakes had separate rupture zones.The first earthquake generated an approximately 280 km coseismic surface rupture along the southwestern segment of the main EAF,with 241 left-lateral displacements reaching up to 6.8±0.68 m,particularly 40 km northeast of the epicenter.The second earthquake produced a roughly 110 km surface rupture on an east-west branch of the EAF,with maximum displacements of 7.2±0.72 m.(2)The MW7.8 earthquake resulted in a cascading rupture across multiple segments of the southwestern section of the main EAF,with significantly variable displacements.The northeastern and southwestern parts of the main EAF and Malatya Fault remain at risk of strong earthquakes in the future.(3)The EAF rupture zone is densely populated,and due to the site amplification effect of loose sediments on foreland alluvial fans,foundation failures of buildings in the populated areas are common.Therefore,it is crucial to enhance the future seismic fortification capabilities in urban and rural areas along the EAF.

关 键 词：Double strong earthquakes of Mw7.8 and Mw7.5 in Tirkiye East Anatolian Fault Surface rupture zone Strong earthquake hazard 

分 类 号：P315.9[天文地球—地震学]