基于PS-InSAR技术的宁波市地面沉降监测研究

STUDY ON LAND SUBSIDENCE MONITORING BASING ON PS-INSAR TECHNIQUE

由大规模抽取地下水和工程建设引发的地面沉降广泛分布于世界各大平原,地面沉降地质灾害使城市损失标高,增加城市在洪涝灾害中的生命财产损失。基于60景Sentinel-1影像,采用PS-InSAR(永久散射体合成孔径雷达干涉测量)技术获取了宁波市2017~2021年平原区地表形变,利用同期水准数据进行了精度和可靠性评定,监测和分析结果表明工程建设是现阶段引发宁波市地面沉降的主要因素;杭州湾新区为代表的沿海围垦区地面沉降与围垦和工程建设时间密切相关;城市建成区地面沉降局限于近期的工程建设区域内,且沉降衰减相对较快。

Due to the extraction of underground water and the engineering construction,land subsidence is widely distributed in the worldwide plains.The cities will lose their elevation because of the settlement which enlarge the economic damages and loss of lives in flood disasters.The surface deformation in Ningbo plain from 2017 to 2021 was obtained by using PS-InSAR(Persistent Scatterer Interferometric Synthetic Aperture Radar)technique based on 60 pieces of Sentinel-1 images,the precision and reliability of the deformation were verified by the leveling data in the same period.The results showed the engineering construction was the major factor resulting in the land subsidence in Ningbo at the present stage.Besides,the settlement in coastal reclamation area such as Hangzhou Bay New Area was significantly related to the time of reclamation and engineering construction.At last,the land subsidence in urban built-up area was limited in the recent engineering construction area and the settlement rate would decelerate rapidly.