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Title: The complex dynamics of the 2023 Kahramanmaraş, Turkey, M w 7.8-7.7 earthquake doublet
The destructive 2023 moment magnitude ( M w ) 7.8-7.7 earthquake doublet ruptured multiple segments of the East Anatolian Fault system in Turkey. We integrate multi-scale seismic and space-geodetic observations with multi-fault kinematic inversions and dynamic rupture modeling to unravel the events’ complex rupture history and stress-mediated fault interactions. Our analysis reveals three sub-shear slip episodes during the initial M w 7.8 earthquake with delayed rupture initiation to the southwest. The M w 7.7 event occurred 9 hours later with larger slip and supershear rupture on its western branch. Mechanically consistent dynamic models accounting for fault interactions can explain the unexpected rupture paths, and require a heterogeneous background stress. Our results highlight the importance of combining near- and far-field observations with data-driven and physics-based models for seismic hazard assessment.  more » « less
Award ID(s):
2121666 2121568 1841273 2123529
NSF-PAR ID:
10447782
Author(s) / Creator(s):
; ; ; ; ; ; ; ; ; ; ;
Date Published:
Journal Name:
Science
ISSN:
0036-8075
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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