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Abstract

Two large earthquakes of Mw 7.8 and Mw 7.5 struck southeast Anatolia on the 6th of February 2023 leaving unseen devastation in southern Turkey and northern Syria. Satellite SAR and optical data contributed to detecting the co-seismic ground displacement by applying SAR interferometry and pixel offset techniques. However, these results are heterogeneous with respect to the observed ground displacement geometry and sensitivity. InSAR derives two-dimensional measurement along the Line-Of-Sight (LOS) in ascending and descending orbit directions, with higher sensitivity to vertical and east-west components, but no sensitivity to north-south oriented displacements and is characterised by a cm level accuracy. Large displacements cause phase decorrelation and therefore limit the InSAR capability to resolve the ground displacement near the ruptured fault. This limitation is overcome by Optical and SAR pixel offset tracking approaches. Optical pixel offset tracking measures the north-south and east-west ground displacement components, while SAR offset tracking measures the along-track and the along-range ground displacement components, both with metre accuracy. In this study, we present a 3D ground displacement model retrieved using data fusion of the aforementioned satellite-observation-based techniques, with the aim to derive more complete co-seismic kinematic information for a better interpretation of the tectonic of the region. We used Sentinel-1 SAR ascending and descending orbit and Sentinel-2 optical data which have complete coverage of the region before and after the earthquake. We will present the method and discuss the main results.