Insights into the Arabia–Anatolia plate collision from integrated SAR analysis and detailed modelling of the 2023 Türkiye–Syria earthquakes

We examine the 6 February 2023 Türkiye–Syria earthquakes using an extensive SAR dataset, addressing some limitations of previous studies. Large surface displacements caused significant loss of coherence in the Sentinel-1 Differential SAR Interferometry (DInSAR) results and prior analyses using Pixel Offset Tracking (POT) were limited by the poor azimuthal resolution of the available Sentinel-1 and ALOS-2 SAR images. For the first time, we present high-azimuth-resolution displacement measurements obtained thanks to the SAOCOM-1 sensors. Azimuth information is important considering that the main movements occurred were horizontal and, in some areas, with an important N-S component. By exploiting multi-frequency Sentinel-1, ALOS-2, and SAOCOM-1 SAR data and applying the DInSAR and POT techniques, where appropriate, we derived a detailed displacement field and retrieved an elaborated fault model comprising 22 segments; this model accurately characterizes the geometry and kinematics of the two main faults. Maximum slip reaches ∼15 m for both faults, and the total seismic moment corresponds to Mw 7.9. A finite-fault ShakeMap generated from this source model shows improved agreement with near-field ground motions relative to point-source formulations, while on-fault static stress changes identify low-slip areas that remained unbroken during rupture. The three-dimensional displacement field reveals a broad uplifted region and opposing horizontal motions between the two main ruptures, indicating distributed deformation within an interfault block that accommodates part of the Arabia–Anatolia convergence. This off-fault deformation has not been documented previously for the 2023 sequence and provides new constraints on strain partitioning and future seismic hazard along the East Anatolian Fault Zone.