Abstract. The Heze section of Rizhao-Lankao High-speed Railway (RLHR-HZ) has been under construction since 2018 and will be operative by the end of 2021. However, there is a concern that land subsidence in Heze region may affect the normal operation of RLHR-HZ. In this study, we investigate the contemporary ground deformation in the region between 2015 and 2019 by using more than 350 C-band interferograms constructed from two tracks of Sentine-1 data over the region. The Small Baselines Subset (SBAS) technique is adopted to compile the time series displacement. We find that the RLHR-HZ runs through two main subsidence areas: One is located east of Heze region with rates ranging from −4 cm/yr to −1 cm/yr, and another one is located in the coal field with rates ranging from −8 cm/yr to −2 cm/yr. A total length of 35 km of RLSR-HZ are affected by the two subsidence basins. Considering the previous investigation and the monthly precipitation, we infer that the subsidence bowl east of Heze region is due to massive extraction of deep groundwater. Close inspections of the relative locations between the second subsidence area and the underground mining reveals that the subsidence there is probably caused by the groundwater outflow and fault instability due to mining, rather than being directly caused by mining. The InSAR-derived ground subsidence implies that it's necessary to continue monitoring the ground deformation along RLSR-HZ.
Assessments of land subsidence along Rizhao-Lankao High-speed Railway at Heze, China between 2015 and 2019 with Sentinel-1 data
