Mapping millimetre-scale ground deformation over the underground coal mines in the Frank Slide area, Alberta, Canada, using spaceborne InSAR technology

This study has applied persistent/permanent scatterers interferometric SAR (PSI) technology to map ground deformation in the Frank Slide area, Alberta, Canada, using RADARSAT-1 data and the EarthView InSAR (EV-InSAR) coherent target monitoring (CTM) software developed by Atlantis Scientific Inc. Frank Slide is a rock avalanche that occurred on the eastern slope of Turtle Mountain in 1903 and claimed more than 70 lives. At the foot of the eastern slope of Turtle Mountain, the ground surface above the Frank Mine was found to subside at an average rate of about 3.1 mm per year, relative to the reference area that is located in the middle part of the Frank Slide, during a period from April 2004 to October 2006. This may support the speculation, suggested for more than 100 years since the Frank landslide took place, that ground movements induced by the underground coal mines at the foot of Turtle Mountain might have triggered the slide. To the east of the Frank Slide debris, an average subsidence rate of up to 3.2 mm per year was observed for some areas overlying the footprint of the abandoned Bellevue underground mine during the same period. This is supported by reported frequent collapses on the ground.