延安新区地表垂直形变时空演化的经验正交函数分析

Spatial and Temporal Evolution of Vertical Deformation of the Ground Surface in Yan’an New Area Using Empirical Orthogonal Function

采用SBAS-InSAR技术对43景Sentinel-1A影像进行处理,获取延安新区(北区)地表形变信息,并运用经验正交函数对结果进行分解,得到研究区域的时间系数和空间分布。结果表明,延安新区(北区)的最大沉降速率为-56 mm/a,最大抬升速率为32 mm/a。从第1模态可以看出,挖方、填方是造成地表抬升和沉降的主要原因;第2模态则反映了工程建设不同时期对应的不同地表形变状态,即加速、减缓、平稳3个阶段。

Using SBAS-InSAR technology to process the 43-view Sentinel-1A images to obtain the surface deformation of Yan’an New Area(north zone),we decompose the monitoring results with empirical orthogonal function analysis to obtain the time coefficients and spatial distribution of the study area.The results show that the maximum settlement rate of Yan’an New Area(north zone)is-56 mm/a and the maximum uplift rate is 32 mm/a.From the mode 1,the excavation and filling are the main causes of surface uplift and settlement.The mode 2 reflects that different periods of construction correspond to different states of surface deformation,i.e.,three stages of acceleration,slowdown,and smoothness.