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The Datong basin is one of the complex geologic environments in China. Several faults are distributed in the basin, and a number of hidden faults have been discovered within the basin. Ground fissures (GFs) and land subsidence occur in this region. In the past, ground subsidence at Datong basin has been studied using groundwater level records, intermittent small-scale levelling measurements and field investigations. However, due to the low spatial resolution and temporal sampling of these records, detailed ground deformation within the basin remains poorly understood. In this study, we exploited Envisat ASAR and ALOS PALSAR images to map the ground deformation between 2007 and 2010. Most of the deformation within the basin occurred at rates of <20 mm/year. In addition to the subsidence due to coal mining in the western mountainous areas, at least four large subsidence zones could be detected. Our analysis indicates that the ground subsidence is affected by groundwater extraction and the distribution of faults. Additionally, the vertical deformation is much larger than the deformation in the east–west direction. Obvious deformation gradients occurred on individual GFs and the activity of the GFs varied spatially. Finally, Interferometric synthetic aperture radar (InSAR) observations related to groundwater exploitation and GFs were modelled and discussed. Abbreviations: GFs: ground fissures; SAR: Synthetic Aperture Radar; ASAR: Advanced Synthetic Aperture Radar; ALOS: Advanced Land Observing Satellite; PALSAR: Phased Array type L-band Synthetic Aperture Radar; InSAR: Interferometric Synthetic Aperture Radar; ESA: European Space Agency; JAXA: Japan Aerospace Exploration Agency; SBAS: Small Baseline Subsets; SRTM: Shuttle Radar Topography Mission; DEM: Digital Elevation Model; DORIS: Dopper Orbitography and Radiopositioning Integrated by Satellite instrument; MCF: minimum cost flow; LOS: line-of-sight2D/3D: two-dimensional/three-dimensional [ABSTRACT FROM AUTHOR]

The Yuncheng Basin (China) is affected by severe land subsidence and ground fissure hazards, which have caused serious land damage and economic losses to the local inhabitants. Due to the lack of long-term continuous monitoring in the region, the trend of land subsidence and fissure activities is unknown, which cannot meet requirements for disaster reduction and disaster prevention. In this study, Envisat ASAR, ALOS PALSAR, and TerraSAR-X are employed to monitor these hazards using time series InSAR methodology. The results showed that there were two obvious subsidence centers occurred in Yuncheng. Compared to the period from 2007 to 2011, the land subsidence rate in the Yuncheng Basin from 2012 to 2015 decreased significantly. Analysis of the differential deformation rate observed by InSAR between the two sides of the ground fissure indicates that fissure activity has weakened in recent years at the cross-section. To explain the phenomena observed by InSAR, FLAC3D was used to study the effect of pumping on ground fissure activity under the condition of pre-existing faults, and the results show that pumping promotes differential activities between two sides of the fault and has a positive impact on the occurrence and the activity of ground fissures. Horizontal rectangular sill with uniform opening model is used to simulate the land subsidence and invert the pumping depth. The results are basically consistent with the local situation. [ABSTRACT FROM AUTHOR]