Rupture Dynamics and Ground Motions Characteristics of the 2023 Türkiye Mw 7.8 and Mw 7.6 Earthquake Doublet
Description:
Earthquake doublets have been observed globally in various tectonic regimes. Their occurrence disagrees with general aftershock evolution laws and thus challenges common approaches for seismic hazard assessment. A better understanding of the rupture evolution and interaction of faults involved in earthquake doublets is thus needed to improve earthquake forecasting and seismic hazard analysis. On February 6, 2023, the destructive earthquake doublet with magnitude 7.8 and 7.6 successively rocked south-central Türkiye and northwestern Syria. Here, we use data-constrained dynamic rupture modeling to investigate the rupture process and ground motions of the earthquake doublet. We find that the complex 3D fault geometry and the regional stress regime generates a distinct pre-stress loading on the multi-segment fault network and leads to complex rupture dynamics, including rupture branching and arresting, forward and backward rupture triggering, transitions between subshear and supershear. Our dynamic models well reproduce InSAR, GPS, local strong motion and teleseismic data. The synthetic ground motions show heterogeneous distribution with strong directivity amplification by subshear ruptures. Supershear rupture elevates the ground motion intensity off the fault, but mitigates the directivity amplification. Our synthetic ground motions illustrate the same distance decay pattern with the observations. In summary, our work highlights the importance of fault geometry and pre-stress loading in determining the complexity in rupture dynamics, and indicates that physics-based modeling can complement the ground motion models for assessing the seismic hazard.
Session: 3D Wavefield Simulations: From Seismic Imaging to Ground Motion Modelling [Poster Session]
Type: Poster
Date: 5/2/2024
Presentation Time: 08:00 AM (local time)
Presenting Author: Bo
Student Presenter: No
Invited Presentation:
Authors
Bo Li Presenting Author Corresponding Author bo.li.3@kaust.edu.sa King Abdullah University of Science and Technology |
Kadek Palgunadi kadek.palgunadi@kaust.edu.sa King Abdullah University of Science and Technology |
Baoning Wu baoningw@usc.edu University of Southern California |
Cahli Suhendi cahli.suhendi@kaust.edu.sa King Abdullah University of Science and Technology |
Yijian Zhou yzhou279@ucr.edu University of California, Riverside |
Abhijit Ghosh aghosh.earth@gmail.com University of California, Riverside |
Paul Mai martin.mai@kaust.edu.sa King Abdullah University of Science and Technology |
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Rupture Dynamics and Ground Motions Characteristics of the 2023 Türkiye Mw 7.8 and Mw 7.6 Earthquake Doublet
Session
3D Wavefield Simulations: From Seismic Imaging to Ground Motion Modelling