Coseismic Kinematics of the 2023 Kahramanmaras, Turkey Earthquake Sequence From InSAR and Optical Data
Lijia He, Guangcai Feng, Wenbin Xu, Yuedong Wang, Zhiqiang Xiong, Hua Gao, Xiaoge Liu
Abstract
Abstract We derive the ALOS‐2 coseismic interferograms, pixel‐offsets and Sentinel‐2 sub‐pixel offsets of the 2023 M w 7.8 and M w 7.7 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 M w 7.8 event are basically consistent with the ∼8.4 m and ∼3.9 mm/yr of the M w 7.7 event. Most coseismic slips of the M w 7.8 and M w 7.7 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 M w 7.7 event is likely promoted by ∼2 bar stress increase from the M w 7.8 event on the central section of its main rupture.