Formigal landslide and other examples on landslides and glaciers movements. Paolo Federici* Landslide monitoring techniques based on remote sensing tools Madrid, 17 Ottobre 2008 PRESENTAZIONE POWER POINT * CESI RICERCA The experimental activities of Terrestrial Laser Scanners (TLS) applications in the field of the geological and glaciological surveying will be shown. The extraction of the surface movements of unstable slopes and glacier flows from multi-temporal point clouds using TLS technique is based on the calculation of a roto-translation matrix, obtained from the alignment of multi-temporal scans and the computation of the mean displacement vectors. A proper workflow for retrieving surface displacements by comparing multi-temporal TLS surveys was developed. Three different applications are presented: the complex landslide of Formigal test site (Huesca, Spain), affected by decimetric yearly displacement rate, a rotational landslide affecting a frontal moraine (Locce Glacier, Macugnaga, M. Rosa, Italy) and the debris covered Belvedere Glacier (Macugnaga, M. Rosa, Italy) with movement of the order of 50 meters per year. Some considerations are developed, relevant to the reliability, precision and operative usefulness of TLS measurements and to their validation by comparison with more conventional instruments. Finally the possibility to obtain automatic and near real time displacement data with an high level of detail of the surface displacements, with respect to the traditional instrumentation (extensometers, distometers, tiltmeters, clinometers). opens the use of TLS techniques to the field of on-line continuous monitoring of unstable slope and its applications in early warning systems.