Utilisation of InSAR for Subsidence Monitoring over the Caving Zone of Underground Metalliferous Mine
Andrew Jarosz(1), Hani Zahiri(1), Mark Warren(2) and Andrew Sowter(2)
(1) Curtin University of Technology, Locked Bag 22, Kalgoorlie 6433, Australia
(2) The University of Nottingham, University Park, NG7 2RD Nottingham, United Kingdom
Utilisation of InSAR technique for monitoring of surface deformation over mining areas, employing open pit and underground mining methods, has large potential due to accessibility and safety issues associated with usage of classical surveying techniques. InSAR can also be very competitive concerning the cost of provided results. However, there are few issues that may significantly limit InSAR applicability for subsidence monitoring in the mining areas with highly dynamic surface subsidence, induced by caving extraction methods. The terrain topography, altered by mining and involving steep slopes and deep pits, may lead to radar signal overlay issues for the specific satellite and pit slope geometry. The second problem could be the rate of ground subsidence with relation to frequency of SAR acquisitions that may lead to ambiguity issues. This could happen when the vertical movement between the neighbouring cells of SAR image is greater then the half of wavelength of the radar signal. In this paper authors analyse the above-mentioned issues and present, how the InSAR technology was applied to monitor large scale and highly dynamic subsidence for the real case study in Western Australia. By combining the InSAR results with other surveying techniques (GPS, slope stability and topographic surveys) the comprehensive model of surface deformations was created. It was also recognised that analysis of ground deformation dynamics, based on topographical surveys, may provide basis for resolution of ambiguity issues existing in InSAR processing.
The obtained model of mining subsidence provided significant help with tuning the finite element analysis required for planning and design of the next mining phase.
Keywords: ESA European
Space Agency - Agence spatiale europeenne,
observation de la terre, earth observation,
satellite remote sensing,
teledetection, geophysique, altimetrie, radar,
chimique atmospherique, geophysics, altimetry, radar,