时序InSAR滑坡探测与DEM误差影响分析

Landslide Detection and Influence Analysis of DEM Errors Using Time Series InSAR

以贵州省西南山区为例,针对地质灾害隐患早期识别的实际情况和需求,开展差分干涉测量和时序InSAR方法的对比实验,以验证时序InSAR在抗误差干扰、探测微小形变、捕捉形变序列演化趋势等方面的能力;再基于高精度LiDAR DEM数据进一步研究DEM误差对时序InSAR处理结果的影响。实验表明,时序InSAR方法无法完全剔除DEM误差,从而导致形变速率、形变序列估计不准,在开展精细化InSAR形变分析时应尽可能选取高精度的外部DEM数据,以保证正确估计地质灾害隐患形变特征。

In this study,taking the mountainous area in southwest of Guizhou for example,we compared the results of differential InSAR and time series InSAR(TSI),and verified the capability of TSI in resisting error interference,detecting weak deformation and capturing the evolution of deformation for the huge demand of geological hazards early identification.And then,we further studied the influence of DEM errors on TSI processing based on high-precision LiDAR DEM data.Experimental result shows that TSI method cannot completely eliminate DEM errors,re-sulting in the inaccurate estimation of deformation rate and deformation sequence.When carrying out refined InSAR deformation analysis,the high-precision DEM data should be selected to ensure the correct estimation of deformation characteristics of geological hazards.