Name
Satellite interferometry for characterization of large slow-moving deep-seated landslides in northern Canada
Description
The large, slow-moving deep-seated landslides are observed in two different regions of northern Canada with the novel advanced Differential Synthetic Aperture Radar (DInSAR) technique. Two-dimensional (2D) vertical and horizontal east-west deformation rates and time series are computed from ascending and descending Sentinel-1 imagery acquired during the 2017-2022 period. The landslides' horizontal deformation rate is significantly larger than the vertical deformation rate, so it is better suited for landslides' characterization. The deformation rates remain nearly constant during the entire period, suggesting substantial landslide thickness. Two large landslides in Alberta and the largest landslide in the Northwest Territories are studied in detail to demonstrate various advanced value-added products that can be produced from standard DInSAR results. The average 2017-2022 line-of-sight deformation rates are used to compute three-dimensional (3D) deformation rates, assuming the Surface-Parallel Flow (SPF) constraint. Two of the landslides have substantial northern deformation components. The third landslide, located in Alberta, has a small northern deformation component, which allows us to estimate the landslide thickness from the unconstraint 3D deformation rates by neglecting the northern deformation component entirely. The proposed methodology maps with superior clarity slow-moving deep-seated landslides in harsh conditions affected by seasonal landcover changes, such as the Arctic. The decomposition of landslide motion into two or three components in certain conditions allows us to derive landslide thickness and volume and improve the estimation of a risk, posed by landslides from remote data alone.