Cascading multi-segment rupture process of the 2023 Turkish earthquake doublet on a complex fault system revealed by teleseismic P wave back projection method  

作　　者：Bonan Cao Zengxi Ge 

机构地区：[1]Department of Geophysics,School of Earth and Space Sciences,Peking University,Beijing 100871,China [2]Hebei Hongshan National Geophysical Observatory for Thick Sediments and Seismic Hazards,Peking University,Beijing 100871,China

出　　处：《Earthquake Science》2024年第2期158-173,共16页地震学报（英文版）

基　　金：supported by the National Key R&D Program of China(No.2022YFF0800601);National Scientific Foundation of China(Nos.41930103 and 41774047).

摘　　要：In this study,the vertical components of broadband teleseismic P wave data recorded by China Earthquake Network are used to image the rupture processes of the February 6th,2023 Turkish earthquake doublet via back projection analysis.Data in two frequency bands(0.5-2 Hz and 1-3 Hz)are used in the imaging processes.The results show that the rupture of the first event extends about 200 km to the northeast and about 150 km to the southwest,lasting~90 s in total.The southwestern rupture is triggered by the northeastern rupture,demonstrating a sequential bidirectional unilateral rupture pattern.The rupture of the second event extends approximately 80 km in both northeast and west directions,lasting~35 s in total and demonstrates a typical bilateral rupture feature.The cascading ruptures on both sides also reflect the occurrence of selective rupture behaviors on bifurcated faults.In addition,we observe super-shear ruptures on certain fault sections with relatively straight fault structures and sparse aftershocks.

关 键 词：2023 Turkish earthquake doublet back projection method cascading segmented rupture process coseismic triggering super-shear ruptures 

分 类 号：P315.7[天文地球—地震学]