Differential Radar Interferometry and Its Application in Monitoring Underground Coal Mining-induced Subsidence

Ground subsidence due to underground coal mining threatens the safety of surface infrastructure such as buildings, roads, bridges, powerlines and telecommunication cables, and can cause environmental problems such as water pollution, cessation of stream flow, and so on. Monitoring the spatial distribution of surface deformation may be helpful for land-use planning, land reclamation, safety and establishing the extent of legal liability. Traditional monitoring techniques that use levels, total stations and GPS can only measure on a point-by-point basis and hence are comparatively costly and time-consuming (Ge et al., 2007). Differential synthetic aperture radar interferometry, or DInSAR, is a remote sensing technique that can measure earth surface deformation. DInSAR is capable of obtaining dense information related to the deformation across a large area in an efficient and economic manner. In this paper, the principles and basic concepts of traditional DInSAR, as well as some advanced DInSAR techniques as PSInSAR, SBAS and IPTA, are introduced, its application to monitoring underground coal mining-induced subsidence is reviewed, and critical issues such as the limitations of these methods and their likely future development are examined. * Corresponding author. Tel.: +0061-422 242 643. E-mail address: [email protected]