Mapping and Analyses of Land Subsidence in Hengshui, China, Based on InSAR Observations

In this paper, we use interferometric synthetic aperture radar (InSAR) annual and time-series analysis of RADARSAT-2 SAR data, spanning from September 2011 to October 2022, study the temporal–spatial characteristics land subsidence in Hengshui, North China Plain. The data reveal two large-scale areas individually located north Hengshui city around Hutuo River east or south along Fuyang, Suolu Qingliang Rivers. fastest arises after 2017, with maximum rate exceeding 11 cm/year. We correlate observed central table variation groundwater depression, three confined aquifers, hydraulic head declines aquifers time-dependent total variation. find a spatial consistency between depression displacement heads both manifest clear seasonal variability. This suggests that is primarily caused by extraction for agricultural use. also observe rates did not decrease but rather increased when significantly rose 2019. It very likely as result occurrence thick widespread continuity clay layers high compressibility Quaternary deposit new preconsolidation could be generated due drop, leading effective still existing aquitards even if rises aquifer systems.