Coseismic Kinematics of the 2023 Kahramanmaras, Turkey Earthquake Sequence From InSAR and Optical Data.

We derive the ALOS‐2 coseismic interferograms, pixel‐offsets and Sentinel‐2 sub‐pixel offsets of the 2023 Mw7.8 and Mw7.7 Kahramanmaras, Turkey earthquake sequence. Offset maps show that the sequence ruptured ∼300 km along the East Anatolian Fault (EAF) and ∼180 km along the secondary Cardak and Dogansehir faults. We infer the coseismic slip distribution and interseismic fault motion by inverting the co‐ and inter‐seismic observations. Inversion results show that the coseismic slip (∼8.0 m) and interseismic strike‐slip rate (∼4.6 mm/yr) on the main rupture of the Mw7.8 event are basically consistent with the ∼8.4 m and ∼3.9 mm/yr of the Mw7.7 event. Most coseismic slips of the Mw7.8 and Mw7.7 events occur within 10 and 12 km at depth, respectively, in keeping with the interseismic locking depth of 10.4 ± 3.3 km and 11.1 ± 3.1 km. This implies that the coseismic rupture kinematics correlate with the interseismic strain accumulation. Moreover, static stress changes show that the Mw7.7 event is likely promoted by ∼2 bar stress increase from the Mw7.8 event on the central section of its main rupture. Plain Language Summary: The middle and northern sections of the East Anatolian Fault (EAF) have experienced seven major earthquakes (M > 6.0) since the twentieth century, in accordance with the fast slip rate (∼10.5 mm/yr) and shallow locking depth (∼5 km) (Bletery et al., 2020, https://doi.org/10.1029/2020gl087775), leaving a well‐known seismic gap, the Pazarcık segment in the southern section of the EAF. Stress analysis by Nalbant et al. (2002, https://doi.org/10.1016/s0012-821x(01)00592-1) suggested that this seismic gap has potential to produce an Mw ≥ 7.3 earthquake. The 2023 Mw7.8 and Mw7.7 Kahramanmaras, Turkey earthquake sequence ruptured the Pazarcık segment. This earthquake sequence offers a valuable opportunity to explore the critical stage of the seismic cycle from interseismic strain accumulation to coseismic rupture. We extract the surface fault traces from the deformation maps derived from the ALOS‐2 interferometric synthetic aperture radar (InSAR), pixel offset and Sentinel‐2 sub‐pixel offset measurements, and then construct a seven‐segment fault geometric model according to the fault segmentation based on Duman and Emre (2013, https://doi.org/10.1144/SP372.14). By inverting the coseismic interferograms and pixel offsets and the interseismic LOS velocities from Weiss et al. (2020, https://doi.org/10.1029/2020GL087376), we determine the coseismic slip model of Mw7.8 and Mw7.7 earthquakes, and relate it to the interseismic kinematics. Key Points: We drive a complete series of coseismic deformation maps and detailed slip distribution of the 2023 Kahramanmaras earthquakesThe Mw7.7 event produced normal dip‐slip (∼6 m) near the Goksun releasing bend and thrust dip‐slip (∼2 m) on the Dogansehir faultThe coseismic slip behaviors on the Cardak and Pazarcık faults correlate with the interseismic kinematics [ABSTRACT FROM AUTHOR]