Radar interferometry for 3-D mining deformation monitoring

Geodetic information of terrain can be measured using remote sensing techniques such as photogrammetry, airborne laser scanner (ALS) and interferometric synthetic aperture radar (InSAR). They are considered to be relatively more cost-effective than and complementary to conventional ground-based surveying methods. Our previous studies demonstrated the capability of using differential InSAR for underground longwall mining subsidence monitoring in New South Wales, Australia. The mining subsidence (vertical surface deformation) was measured using DInSAR with the assumption of negligible horizontal deformation. However, the ground surveying data shows that the underground mining activity may induce horizontal surface deformation. Therefore, both ascending and descending orbits and different swath modes of ENVISAT/ASAR data are used in this paper to quantify the vertical and horizontal vectors of mining deformation.