The main aim of this work is to create a detailed geomorphological map of the Tessina Landslide, through the analysis of images acquired by UAV. This is a very complex landslide located in the venetian Alps (Province of Belluno). The first movement occurred in 1960, after which a lot of reactivations have taken place, the main one being in 1992. The study was carried out using a high-resolution digital elevation model (DEM) obtained using a series of images of the landslide acquired through a drone survey and processed using Agisoft Metashape software. Photogrammetry investigation was able to collect geomorphological evidence such as scarps and cracks that allow to identify the most unstable portions of the landslide and, therefore, to estimate its spatial evolution. These morphological features have been reported in a GIS environment to obtain an effective representation of the instability phenomenon. The result of the work was compared with the previous geomorphological map of the Tessina Landslide, dating back to 1999, and with the displacement fields measured thorough ground-based (total station) and satellite (interferometry) remote sensing methods, to assess the state of activity of the most unstable areas, allowing a temporal estimation of the future evolution of the landslide. Obtained results showed that the combination of well-known investigation techniques, such as geomorphological survey, and recently developed methods (UAV and satellite RADAR interferometry) allow an accurate estimation of the spatial and temporal evolution of landslides, which is a crucial element in the planning of structural and non-structural measures to mitigate landslide risk.
Lo scopo principale di questo lavoro è realizzare una carta geomorfologica di dettaglio della frana del Tessina attraverso l’analisi di immagini telerilevate da drone. Si tratta di una frana molto complessa situata nelle Alpi venete (Provincia di Belluno), che si è innescata per la prima volta nel 1960 e da allora ha avuto numerose riattivazioni, la principale nel 1992. Lo studio è stato svolto utilizzando un modello digitale di elevazione (DEM) ad alta risoluzione ricavato con l’ausilio di una serie di immagini della frana che sono state acquisite con l’utilizzo di un drone e successivamente elaborate attraverso il software Agisoft Metashape. Il rilievo fotogrammetrico ha permesso di rilevare indicatori quali scarpate e fessurazioni che permettono di individuare le porzioni più instabili della frana e, quindi di ipotizzare la sua evoluzione spaziale. Queste caratteristiche morfologiche sono state elaborate utilizzando un software GIS che ha permesso una efficace rappresentazione del fenomeno di instabilità. Il risultato del lavoro è stato confrontato con la precedente carta geomorfologica della Frana del Tessina, risalente al 1999, e con i campi di spostamento misurati attraverso tecniche di telerilevamento da terra (stazione totale) e da satellite (interferometria), al fine di valutare lo stato di attività delle aree più instabili, permettendo una stima temporale dell’evoluzione futura del fenomeno franoso. Tali risultati hanno evidenziato che la combinazione di tecniche di indagine consolidate, come il rilevamento geomorfologico, e di recente sviluppo (UAV e interferometria RADAR satellitare) permettano una accurata stima dell’evoluzione spaziale e temporale dei fenomeni franosi, elementi essenziali per la messa in opera di azioni strutturali e non strutturali di mitigazione del rischio da frana.
Analisi geomorfologica di dettaglio della Frana del Tessina (Alpi venete, Belluno)
SECCO, ELENA
2022/2023
Abstract
The main aim of this work is to create a detailed geomorphological map of the Tessina Landslide, through the analysis of images acquired by UAV. This is a very complex landslide located in the venetian Alps (Province of Belluno). The first movement occurred in 1960, after which a lot of reactivations have taken place, the main one being in 1992. The study was carried out using a high-resolution digital elevation model (DEM) obtained using a series of images of the landslide acquired through a drone survey and processed using Agisoft Metashape software. Photogrammetry investigation was able to collect geomorphological evidence such as scarps and cracks that allow to identify the most unstable portions of the landslide and, therefore, to estimate its spatial evolution. These morphological features have been reported in a GIS environment to obtain an effective representation of the instability phenomenon. The result of the work was compared with the previous geomorphological map of the Tessina Landslide, dating back to 1999, and with the displacement fields measured thorough ground-based (total station) and satellite (interferometry) remote sensing methods, to assess the state of activity of the most unstable areas, allowing a temporal estimation of the future evolution of the landslide. Obtained results showed that the combination of well-known investigation techniques, such as geomorphological survey, and recently developed methods (UAV and satellite RADAR interferometry) allow an accurate estimation of the spatial and temporal evolution of landslides, which is a crucial element in the planning of structural and non-structural measures to mitigate landslide risk.The text of this website © Università degli studi di Padova. Full Text are published under a non-exclusive license. Metadata are under a CC0 License
https://hdl.handle.net/20.500.12608/52510