Hydrometeorological forcing of mass movements at the Slumgullion landslide

Map of the Slumgullion landslide. a, Landslide landscape. Red and blue boxes show swaths from Sentinel-1 ascending (T49) and descending (T56) tracks, respectively. White box shows UAVSAR swaths. Black and gray lines outline the active and inactive landslides. White diamonds show the locations of three extensometers; the borehole inclinometer was located near the center extensometer. Red lines show updated boundaries from this study, and dashed lines are tentative. b&c, Sentinel-1 line-of-sight displacements positive towards the satellite.

Project Summary With its large area of ~1 km2 and perennial motions at ~10-20 mm/day, the Slumgullion landslide in Colorado, USA, represents an ideal natural laboratory to better understand landslide behavior. Here, we use hybrid remote sensing data and methods to recover the four-dimensional surface motions during 2011-2018. We refine the boundaries of an area of ~0.35 km2 below the crest of the prehistoric landslide. We construct a mechanical framework to quantify the rheology, subsurface channel geometry, mass flow rate, and spatiotemporally dependent pore-water pressure feedback through a joint analysis of displacement and hydrometeorological measurements from ground, air and space. Variations in recharge, mainly from snowmelt, drive multi-annual decelerations and accelerations, during which the head of the landslide is the most responsive. The power-law flow theory helps reconcile the mass movement with the subsurface geometry which is explicitly characterized by a novel description of the landslide thickness, the steepness between the lateral and bed shear surfaces, and the tilt of the basal bed.

Tools Hybrid UAVSAR InSAR and pixel offset tracking, Sentinel-1 InSAR, meteorological records, surface extensometer and subsurface inclinometer deformation measurements

Geographic Location Slumgullion, Colorado

Group Members Involved Xie Hu <Email> <Personal Web Site>
Roland Bürgmann
William Schulz
Eric Fielding

Project Duration 2018 - 2020

More Information Nature Communications article < Hu et al., 2020 >