The combined application of continual Global Positioning System data (tall temporal resolution) with spaceborne interferometric synthetic aperture radar data (tall spatial resolution) can reveal much more about the complexity of large landslide movement than is possible with geodetic measurements tied to only a few specific measurement sites. This approach is applied to an ~4 km2 reactivated translational landslide in the Columbia River Gorge (Washington State),which moves mainly during the winter rainy season. Results reveal the complex three-dimensional shape of the landslide mass, how onset of sliding relates to cumulative rainfall, or how surface velocity during sliding varies with location on the topographically complex landslide surface,and how the ground surface subsides slightly in weeks prior to downslope sliding.
Source: usgs.gov