基于高分辨率SAR的三峡库区地表形变分析--以巴东城区为例

Application of high resolution SAR in surface deformation in Three Gorges ReservoirArea:case of Badong urban area

长江三峡地区位于川鄂交接的山地峡谷地区,山多坡陡,一旦遇上暴雨天气或地震灾害极易发生滑坡、泥石流或岩崩等灾害。为了更好地掌握三峡库区地面沉降变形情况,以库区内地质灾害风险较高的巴东县城区为例,选取该区域20景2016~2017年间的PALSAR2数据,基于时间序列InSAR方法进行了地表形变分析;并利用高切坡位移监测数据进行了验证,以更好地了解该区域地形稳定情况。结果表明:InSAR监测结果与该区域同时期高切坡监测实际位移变化情况一致;巴东城区在此期间整体形变速率较小,绝大部分区域年均形变速率在20 mm/a以下;部分变形较大区域与已查明的滑坡区域和土地利用类型变化区域一致。

The Three Gorges Reservoir Area,located in the steep mountain canyon area,is prone to landslide,debris flow or rock fall in case of rainstorm weather or earthquake.In order to better obtain the ground subsidence and deformation in the Three Gorges Reservoir Area,taking the Badong County with high risk of geological disasters within the reservoir area as an example,we selected 20 scenes of PALSAR2 data from 2016 to 2017 to analyze the land deformation based on time series InSAR method.And the results were verified by high-cutting slope displacement monitoring data to better understand the surface stability in the region.The results showed that the InSAR monitoring results were consistent with the actual high-cutting slope displacement monitoring data;the overall deformation rate in the Badong urban area was small during this period,and the average annual deformation rate of most regions was below 20 mm/a;the large deformation area was basically consistent with the identified landslide area and land use type change area.