Multi‐Scale Rupture Growth With Alternating Directions in a Complex Fault Network During the 2023 South‐Eastern Türkiye and Syria Earthquake Doublet

Abstract

A devastating doublet of earthquakes with moment magnitude MW 7.9 and MW 7.6 earthquakes contiguously occurred in SE Türkiye near the NW border of Syria. Here we perform a potency‐density tensor inversion to simultaneously estimate rupture evolution and fault geometry for the doublet. We find the initial MW 7.9 earthquake involved discrete episodes of supershear rupture and back‐rupture propagation, and was triggered by initial rupture along a bifurcated splay of the East Anatolian Fault. The second MW 7.6 event was triggered by the earlier MW 7.9 event, and it involved more extensive supershear rupture along a favorably curved fault, and was likely stopped by geometric barriers at the fault ends. Our results highlight the multi‐scale cascading rupture growth across the complex fault network that affects the diverse rupture geometries of the 2023 Türkiye earthquake doublet, contributing to the strong ground shaking and associated devastation.

Space Geodetic Insights to the Dramatic Stress Rotation Induced by the February 2023 Turkey‐Syria Earthquake Doublet

“…Average residual displacements in EW, NS, and UD directions are 7.2, 6.3, and 4.1 cm, respectively. Slip distribution exhibits multiple major asperities along total fault length of ∼500 km, similar to previous models (Barbot et al, 2023;Okuwaki et al, 2023). The Mw7.8 event's slip pattern comprises at least six asperities, with the most prominent one on the Pazarcık segment, aligned with the reported supershear segment (Melgar et al, 2023;Okuwaki et al, 2023).…”

The complex dynamics of the 2023 Kahramanmaraş, Turkey, M w 7.8-7.7 earthquake doublet

“…When applied to complex ruptures on multiple faults, conventional earthquake source imaging often involves oversimplified assumptions, yielding stark differences in source models and their interpretations ( 14 , 15 ). Initial studies of the Kahramanmaraş earthquakes presented a wide range of earthquake models and interpretations ( 16 – 21 ), likely from focusing on particular datasets and aspects of the rupture process. These differences motivate unified and self-consistent approaches that integrate diverse datasets with state-of-the-art rupture models to advance our understanding of the earthquake dynamics.…”

Dynamic Rupture Process of the 2023 Mw 7.8 Kahramanmaraş Earthquake (SE Türkiye): Variable Rupture Speed and Implications for Seismic Hazard

“…(2023), Okuwaki et al. (2023), and USGS (2023) (for details see Goldberg, Taymaz, Reitman, et al., 2023; Goldberg, Taymaz, Yeck, et al., 2023). All the results show consistency in terms of duration and seismic moment release characteristics, with the maximum peak occurring at 20–30 s and the second peak at 40–50 s. These two peaks correspond to the two periods of maximum energy release for this earthquake.…”