5:15 PM - 7:15 PM
[SSS07-P13] Coseismic and postseismic deformation and seismic hazard of the 2023 Turkey earthquake doublet
Keywords:Earthquake, surface deformation, fault slip, post-seismic slip
On February 6, 2023, two earthquakes of Mw7.8 and Mw7.5 occurred on the East Anatolian Fault (EAF) and the Sürgü Fault (SF) in southeastern Turkey. These events caused surface ruptures of about 350 km and 150 km, respectively, and triggered numerous aftershocks along the faults, indicating ongoing postseismic stress adjustments and potential seismic hazards. In this study, we combine pixel offset tracking and time-series InSAR techniques to monitor the coseismic and postseismic surface deformation of the earthquake doublet. By analyzing fault slip distributions and Coulomb stress changes, we reveal the characteristics of fault activity and the evolution of seismic hazard.
In agreement with some previous studies, the coseismic slip was mainly concentrated in the central-eastern segments of the EAF (Pazarcik and Erkenek segments) and the central segment of the SF (Cardak segment), dominated by left-lateral strike-slip motion. In addition, postseismic slip mainly occurred at the northeastern and southwestern ends of the EAF and the eastern segment of the SF (Maltaya segment). This process reduced the stress accumulation in the locked zone between the eastern end of the EAF and the rupture zone of the 2020 Mw6.9 earthquake, as well as in the southwestern segment of the EAF. This study highlights the critical role of postseismic slip in the regulation of fault rupture processes and provides valuable insights for the seismic hazard assessment in the Arabain-Eurasian plate collision zone.
In agreement with some previous studies, the coseismic slip was mainly concentrated in the central-eastern segments of the EAF (Pazarcik and Erkenek segments) and the central segment of the SF (Cardak segment), dominated by left-lateral strike-slip motion. In addition, postseismic slip mainly occurred at the northeastern and southwestern ends of the EAF and the eastern segment of the SF (Maltaya segment). This process reduced the stress accumulation in the locked zone between the eastern end of the EAF and the rupture zone of the 2020 Mw6.9 earthquake, as well as in the southwestern segment of the EAF. This study highlights the critical role of postseismic slip in the regulation of fault rupture processes and provides valuable insights for the seismic hazard assessment in the Arabain-Eurasian plate collision zone.