2020斯坦利地震同震形变及断层滑动分布反演

Coseismic deformation and slip distribution inversion of the 2020Stanley earthquake

针对2020年3月31日斯坦利地震造成同震形变场及断层运动特征的研究,该文基于D-InSAR技术获取了斯坦利地震同震形变信息。基于两步反演法,获取了发震断层分布式滑动分布,该方法通过非线性反演获取了斯坦利地震断层几何参数,通过线性反演得到断层面上的精细滑动分布。同震形变结果表明:斯坦利地震升轨隆升形变量24.2cm,沉降量12.5cm,降轨隆升形变量22.3cm,沉降量14.1cm。滑动分布结果显示:断层破裂未延伸至地表,断层滑动以左旋走滑为主,主要集中在地下10~12km,最大滑动量约为0.9m,出现在地下12km处。

In order to research on the coseismic deformation field and fault slip characteristics caused by the Stanley earthquake on March 31,2020,this paper obtained the coseismic deformation information of the Stanley earthquake based on the D-InSAR technology.Based on the two-step inversion method,the slip distribution of the fault was obtained.During the modeling,a nonlinear inversion scheme was adopted to determine the fault geometry parameters,and a linear inversion was performed to estimate the slip distribution along the modeled fault.The coseismic deformation results showed that the uplift variable were 24.2cm and 22.3cm,and subsidence variable were 12.5cm and 14.1cm of the ascending and descending interferograms,respectively.The slip distribution results displayed that the fault rupture did not extend to the surface,and the fault slip was dominated by left-lateral strike-slip,mainly concentrated at 10~12km underground,with a maximum slip of about 0.9m,which occurred at 12km underground.