The potential of point clouds for the analysis of rock kinematics in large slope instabilities: examples from the Swiss Alps: Brinzauls, Pizzo Cengalo and Spitze Stei

Lidar measurements and UAV photogrammetry provide high-resolution point clouds well suited for the investigation of slope deformations. Today, however, the information contained in these point clouds is rarely fully exploited. This study shows three examples of large-scale slope instabilities located in Switzerland, which are actively monitored for reasons of hazard prevention. We used point clouds acquired by terrestrial laser scanning to (1) identify differences in kinematic behaviour of individual rock compartments; (2) highlight active shear planes within the moving rock mass; (3) define the kinematic process driving the slope displacements; (4) model basal sliding planes based on the 3D surface movements of rock slides; (5) calculate exact displacement angles, (6) provide estimates on destabilised rock volumes. This information has significantly contributed to the process understanding and has thus supported decision-making in hazard management.

Automated summary

This study demonstrates the utilization of high-resolution point clouds from lidar and UAV photogrammetry for the investigation of large-scale slope instabilities in Switzerland. By analyzing the point cloud data, differences in kinematic behavior of individual rock compartments, active shear planes within the moving rock mass, and the kinematic process driving the slope displacements were identified. Furthermore, basal sliding planes were modeled based on the 3D surface movements of rock slides, displacement angles were calculated accurately, and estimates on destabilized rock volumes were provided. This information significantly contributed to the understanding of the processes and supported decision-making in hazard management.