Journal of Geodesy and Geoinformation Science ›› 2022, Vol. 5 ›› Issue (1): 60-72.doi: 10.11947/j.JGGS.2022.0107

• Special Issue • Previous Articles     Next Articles

Spatial and Temporal Evolution of Surface Subsidence in Tianjin from 2015 to 2020 Based on SBAS-InSAR Technology

Lyu ZHOU1(),Yizhan ZHAO1(),Zilin ZHU2,Chao REN1,Fei YANG3,Ling HUANG1,Xin LI4   

  1. 1. College of Geomatics and Geoinformation, Guilin University of Technology, Guilin 541004, China
    2. Beijing Vastitude Technology Co., Ltd., Beijing 100191, China
    3. Geoscience and Survey Engineering College, China University of Mining and Technology (Beijing), Beijing 100083, China
    4. College of Geology Engineering and Geomantic, Chang’an University, Xi’an 710054, China
  • Received:2021-07-15 Accepted:2022-01-02 Online:2022-03-20 Published:2022-03-31
  • Contact: Yizhan ZHAO E-mail:zhoulv@glut.edu.cn;1722393110@qq.com
  • About author:Lyu ZHOU (1988—), male, PhD, associate professor, majors in InSAR data processing theory and algorithm, and geohazard monitoring. E-mail: zhoulv@glut.edu.cn
  • Supported by:
    Natural Science Foundation of Guangxi(2018GXNSFBA050006);Natural Science Foundation of Guangxi(2020GXNSFBA159033);Wuhan Science and Technology Plan Project(2019010702011314);Guangxi Science and Technology Plan Project(GUIKE AD19110107);National Natural Science Foundation of China(42064003);National Natural Science Foundation of China(42064002);Guangxi Universities Young and Middle-aged Teachers’ Basic Scientific Research Ability Improvement Project(2020KY0603)

Abstract:

Tianjin is one of the inland cities with the most severe cases of subsidence hazard in China. The majority of the existing studies have mainly focused on Beijing-Tianjin-Hebei, and little attention has been given to Tianjin. In addition, these existing studies are short-term investigations, lacking long-term monitoring of surface subsidence. In the present study, we use the Small Baseline Subset Interferometric Synthetic Aperture Radar (SBAS-InSAR) technique to monitor the subsidence process in Tianjin between 2015 and 2020 and reveal its spatial and temporal variation. We divided the 44-view Sentinel-1A image data into three periods to avoid the effect of temporal and spatial decoherence by extracting the surface deformation field in Tianjin. We finally verified the accuracy and reliability of the inversion results using second-order leveling data. Results showed that the correlation coefficient r between the two reached 0.89, and the root mean square error was 4.84mm/y. Obvious subsidence funnels exist in Tianjin, mainly in the towns of Wangqingtuo and Shengfang. These subsidence funnels have a subsidence deformation rate of -136.2mm/y and a maximum cumulative settlement of -346.3mm within the study period. The subsidence area tends to extend to the southwest. The analysis of annual rainfall, groundwater resource extraction, spatial location distribution of industrial areas combined with SBAS-InSAR inversion results indicates that overextraction of groundwater resources is the main cause of land subsidence in the area. Therefore, strict control of groundwater extraction is the main approach to mitigate land subsidence effectively.

Key words: land subsidence; SBAS-InSAR; Tianjin; groundwater change