Co-seismic deformation for the 2015 M_(W)7.8 Gorkha earthquake(Nepal)using near-field GPS data

查看全文 作　　者：Jing [1,2,3]Xiong;Chao [4]Chen;Jiaming [4]Cao;Junxiang [4]Wang;Xingbo [5]Liu 机构地区：[1]Institute of Seismology,China Earthquake Administration,Wuhan 430071,China;[2]Key Laboratory of Earthquake Geodesy,China Earthquake Administration,Wuhan 430071,China;[3]Hubei Earthquake Administration,Wuhan 430071,China;[4]Hubei Subsurface Multi-Scale Imaging Key Laboratory,Institute of Geophysics&Geomatics,China University of Geosciences(Wuhan),Wuhan 430074,China;[5]Hubei Huazhong Electric Power Technology Development Co.,Ltd.,Wuhan 430077,China 出　　处：《Geodesy and Geodynamics》索引2023年第14卷第5期,共12页 基　　金：funded by the Open Fund of Wuhan,Gravitation and Solid Earth Tides,National Observation and Research Station (grant no. WHYWZ202212);the CMONOC project 摘　　要：Seasonal variations and common mode errors affect the precision of the Global Positioning System(GPS)time series.In this paper,we explore to improve the precision of coordinate time series,thereby providing a better detection of weak or transient deformation signals,particularly co-seismic signals.Based on 97 GPS stations,including the campaign and continuous GPS stations in Nepal and southern Tibet,we first consider seasonal variations and common errors,then obtain co-seismic deformation of the 2015 Gorkha earthquake in Nepal and southern Tibet.Our co-seismic rupture model is characterized by a shallow ramp and a deeper detachment fault,in agreement with the relocated aftershock sequence.Our results indicate that the earthquake rupture is mainly distributed in the upper-crustal fault,and the maximum slip is up to 8.0 m at~15.0 km depth located in the approximate-80 km east of the epicenter.The average slip is more than 5 m,and the total modelled magnitude is M_(W)7.84,consistent with the observed seismic moment.Our rupture model for the 2015 Gorkha earthquake suggests that the rupture zone is not only in the upper crustal Main Himalayan Thrust(MHT),but also spreads to the northern segment of the MHT. 关 键 词：GPS time series Co-seismic deformation Nepal earthquake