High-resolution seismicity imaging and early aftershock migration of the 2023 Kahramanmara?(SE Türkiye)M_W7.9&7.8 earthquake doublet  

作　　者：Hongyang Ding Yijian Zhou Zengxi Ge Tuncay Taymaz Abhijit Ghosh Haoyu Xu Tahir Serkan Irmak Xiaodong Song 

机构地区：[1]Institute of Theoretical and Applied Geophysics,Peking University,Beijing 100871,China [2]Department of Earth and Planetary Sciences,University of California,Riverside CA 92521,USA [3]Hebei Hongshan National Observatory on Thick Sediments and Seismic Hazards,Hebei 054000,China [4]Department of Geophysical Engineering,The Faculty of Mines,İstanbul Technical University,Maslak 34467,Sarıyer,İstanbul,Türkiye [5]Department of Geophysical Engineering,Kocaeli University,Umuttepe 41380,Kocaeli,Türkiye

出　　处：《Earthquake Science》2023年第6期417-432,共16页地震学报（英文版）

基　　金：jointly supported by the National Key R&D Program (No.2022YFF0800601);the Istanbul Technical University Research Fund (ITU-BAP);the Alexander von Humboldt Foundation Research Fellowship Award for providing computing facilities through the Humboldt-Stiftung Follow-Up Program;the University of California,Riverside。

摘　　要：We build a high-resolution early aftershock catalog for the 2023 SE Türkiye seismic sequence with PALM,a seamless workflow that sequentially performs phase picking,association,location,and matched filter for continuous data.The catalog contains 29,519 well-located events in the two mainshocks rupture region during 2023-02-01–2023-02-28,which significantly improves the detection completeness and relocation precision compared to the public routine catalog.Employing the new PALM catalog,we analyze the structure of the seismogenic fault system.We find that the Eastern Anatolian Fault(EAF)that generated the first M_(W)7.9 mainshock is overall near-vertical,whereas complexities are revealed in a small-scale,such as subparallel subfaults,unmapped branches,and stepovers.The seismicity on EAF is shallow(<15 km)and concentrated in depth distribution,indicating a clear lock-creep transition.In contrast,the SürgüFault(SF)that is responsible for the second M_(W)7.8 mainshock is shovel-shaped for the nucleation segment and has overall low dip angles(~40°–80°).Aftershocks on the SF distribute in a broad range of depth,extending down to~35 km.We also analyze the temporal behavior of seismicity,discovering no immediate foreshocks within~5 days preceding the first mainshock,and no seismic activity on the SF before the second mainshock.

关 键 词：2023 Türkiye Earthquake Doublet aftershock catalog PALM fault imaging aftershock migration 

分 类 号：P315[天文地球—地震学] P317[天文地球—固体地球物理学]