地球与行星物理论评（中英文）2024，Vol.55Issue(4)：453-460,8.DOI:10.19975/j.dqyxx.2024-010
2024年1月23日MW7.0乌什地震InSAR同震形变场和断层滑动分布
Coseismic deformation and slip model of the 2024 MW7.0 Wushi earthquake obtained from InSAR observation
摘要
Abstract
On January 23,2024,an MW7.0 earthquake occurred in Wushi County.This earthquake was the largest earthquake event in the south Tianshan Fault Zone in the past century.In order to determine the seismoge-nic structure of the Wushi earthquake and analyze the regional tectonic stress characteristics,we obtained the co-seismic deformation field using radar interferometry and pixel offset based on Sentinel-1A data,and estimated the optimal fault geometric parameters applying the Bayesian nonlinear inversion.The results show that the maximum ascending line-of-sight uplift displacement is～80 cm,and the maximum line-of-sight subsidence is～16 cm.The line-of-sight coseismic deformation and pixel offsets indicate the significant vertical deformation characteristics of the Wushi earthquake,while the reverse pixel offset results in the azimuth direction of the ascending and descend-ing orbit indicate obvious left-lateral strike-slip on the seismogenic fault.The inversion results show that the seis-mogenic fault of the Wushi earthquake is SW trending,NW dipping,with an optimal fault dip angle of～67°and an average rake angle of～60°,indicating that the coseismic slip is mainly driven by thrust-slip motion with a minor left-lateral strike-slip component.The deformation pattern and fault geometry parameters of the Wushi earthquake are consistent with the kinematics and geometry of the Maidan-Shayilamu fault at the basin-mountain boundary in the southern margin of the Tianshan Mountains.The high dip angle fault with strike-and thrust-slip activity of the Wushi earthquake indicates oblique convergence between the southern Tianshan Mountains and the Tarim Basin,and emphasizes that crustal shortening in the Tianshan region is absorbed by the nascent thrust nappe belts in the piedmont areas and the reverse faults with high dip angles in the orogenic regions.关键词
乌什地震/同震形变场/断层滑动分布/逆冲推覆体Key words
Wushi earthquake/coseismic deformation/coseismic slip distribution/thrust nappe分类
地球科学引用本文复制引用
赵磊,陈志丹,谢磊,朱志辉,许文斌..2024年1月23日MW7.0乌什地震InSAR同震形变场和断层滑动分布[J].地球与行星物理论评（中英文）,2024,55(4):453-460,8.基金项目
国家自然科学基金面上资助项目(42174023) （42174023）
国家重点研发计划课题(2022YFB3903602) （2022YFB3903602）
中南大学前沿交叉研究资助项目(2023QYJC006)Supported by the National Natural Science Foundation of China(Grant No.42174023),the National Key Research and Develop-ment Program(Grant No.2022YFB3903602),and the Frontier Cross Research Project of Central South University(Grant No.2023QYJC006) （2023QYJC006）
