张家口-宣化盆地现今地壳变形特征与断层滑动速率反演

Characteristics of Present-Day Crustal Deformation and Inversion ofFault Slip Rate in the Zhangjiakou-Xuanhua Basin

基于PS-InSAR结合先验条件的最小二乘迭代逼近法,利用3轨道Sentinel-1数据获取张家口-宣化盆地及周边区域地表三维形变速率场,并在此基础上使用剖面投影法和由刃型位错提出的倾滑断层震间形变数学表达式,反演得到张家口断裂和宣化盆地南缘断裂滑动速率和闭锁深度。断层参数结果显示,张家口断裂中段和宣化盆地南缘断裂闭锁程度较高,具备发生中强以上地震的应变能积累背景条件。

We use Sentinel-1 data of three tracks to obtain the three-dimensional surface deformation rate field in the Zhangjiakou-Xuanhua basin and its surrounding area by using the PS-InSAR and the least-squares iterative approximation method combining prior conditions.We calculate the slip rate and locking depth of the Zhangjiakou fault and the southern margin fault of Xuanhua basin by profile projection and the mathematical expression for interseismic deformation of dip-slip faults of edge dislocation.The results of fault parameters show that the middle section of Zhangjiakou fault and the southern margin fault of Xuanhua basin have a high locking degree and background condition for strain energy accumulation to occur moderate to strong earthquake.