3D displacement vector calculation of rockslides based on satellite and ground-based InSAR

DRAGON is a follow-up project to VIGILANS and addresses the open questions that arose from VIGILANS to achieve an improved hazard analysis of slow slope movements for society. To determine the hazard potential of different deformation types, the depth and geometry of the fracture surface (sliding surface) is determined using the vector inclination method (VIM) based on 3D motion vectors obtained by combining 2D InSAR data (Sentinel-1 and TerraSAR-X) with ground-based InSAR data (GB-InSAR). In addition, Envisat and Sentinel-1 analyses are used to retrospectively determine the slope deformation trajectories for the two selected active slope movements (Steinlenen & Malgrube, Tyrol) for the past twenty years. This allows to assess whether the documented spontaneous rockfall events are directly coupled to the progressive failure of the large slope movements. Time series analyses will identify potential acceleration phases and will be compared with meteorological data series. Due to the known, complex motion behavior of deep-seated slope deformations, it is important to adopt a research approach that integrates multiple technologies and platforms. DRAGON combines for the first time satellite data with ground-based remote sensing (GB-InSAR, TLS, tacheometry, drone photogrammetry) and in situ measurements (D-GNSS, convergence measurements, seismic monitoring). The goal is to create a three-dimensional kinematic model for the two large slope movements that is as accurate as possible and reflects the results of the different measurements and also allows a forecast of the further course of the slope failure. The results form an important contribution to the process understanding of deep slope deformations and can be applied to a large number of mass movements of this type.