Spaceborne Radar Interferometry for Mine Subsidence Monitoring in Australia

Land surface deformation can be caused by underground mining activities. The maximum subsidence normally occurs directly above the location of the excavation of the coal seam. In the case where the longwall mining technique is applied, the magnitude and shape of the subsidence bowl are constrained by the longwall structure (pillar). This paper describes the use of satellite radar interferometry for monitoring surface subsidence due to underground mining, as a cost-effective geodetic technique and complementary to conventional ground surveying techniques. This paper uses data acquired by the current generation of SAR satellites the European ENVISAT and the Japanese ALOS to monitor ground subsidence in the southern highland coal field in NSW, Australia. An accumulated DInSAR subsidence mine map is produced using 6 successive ALOS acquisitions. The results are postanalysed with the aid of geographic information systems (GIS) and validated using ground survey data.