Inferring Subsurface Compaction from InSAR Land Subsidence Measurements Using The Mogi's Model

Interferometric synthetic aperture radar (InSAR) is widely used in land subsidence monitoring. However, how to infer the subsidence mechanism and subsurface soil compaction remains to be resolved. In this paper, we tried to apply the Mogi's model to infer the subsurface compaction from InSAR measurements, assuming that the subsurface compaction is integration of distributed void points. First an array of void points with certain depths representing the groundwater layer were initially set up with random volumetric values. The volumes of each spherical cavity points were iteratively calculated using the Mogi's model to simulate the surface dislocation measured by the InSAR technique. In this way the underground soil compaction volume was inferred finally. Cangzhou City in the Northern China was selected as the test area, and the Sentinel-1 SAR data was used for InSAR measurements. The preliminary result shows that the compression volume of underground soil in Cangzhou City is about 7.5 mm - 11.5 mm in the vertical direction in 2020.