Estimating mass-wasting processes in active earth slides – earthflows with time-series of High-Resolution DEMs fromphotogrammetry and airborne LiDAR

This paper deals with the use of time-series ofHigh-Resolution Digital Elevation Models (HR DEMs) obtainedfrom photogrammetry and airborne LiDAR coupledwith aerial photos, to analyse the magnitude of recently reactivated large scale earth slides – earth flows located in thenorthern Apennines of Italy. The landslides underwent completereactivation between 2001 and 2006, causing civil protectionemergencies. With the final aim to support hazardassessment and the planning of mitigation measures, highresolution DEMs are used to identify, quantify and visualizedepletion and accumulation in the slope resulting from the reactivation of the mass movements. This information allowsto quantify mass wasting, i.e. the amount of landslide materialthat is wasted during reactivation events due to streamerosion along the slope and at its bottom, resulting in sedimentdischarge into the local fluvial system, and to assessthe total volumetric magnitude of the events. By quantifyingand visualising elevation changes at the slope scale, resultsare also a valuable support for the comprehension of geomorphological processes acting behind the evolution of theanalysed landslides.