Over the last decades, a movement has begun to reclassify deposits previously misidentified as having origins other than landsliding. The reverse problem of incorrectly assigning deposits a mass movement origin, however, has been addressed less in the landslide community. The Cima Salti Landslide in the Lake Garda region of Northern Italy is a cautionary tale of assuming source areas and volumes. It was traditionally thought to have dammed Tenno Lake in the Middle Ages, and to have a volume of 20–30 Mm3. We show through geological field data and simple runout simulations with the codes DAN3D and SHALTOP (which produced comparable results) that the volume of the landslide was likely significantly overestimated in the past, and that it most likely did not dam Tenno Lake, as has been assumed. We propose that a smaller volume landslide (2–5 Mm3) was deposited on stagnant ice melting in situ in the Lateglacial period, a relatively minor event in the complex history of the Magnone valley. This interpretation emphasizes the importance of careful field investigations and assumption validation, at Cima Salti and in a broader context. It also shows the unique capacity of landslide simulation to guide field observation and discriminate mass emplacement processes.
Forensic investigations of the Cima Salti Landslide, northern Italy, using runout simulations
Ghirotti, MonicaUltimo
Conceptualization
2018
Abstract
Over the last decades, a movement has begun to reclassify deposits previously misidentified as having origins other than landsliding. The reverse problem of incorrectly assigning deposits a mass movement origin, however, has been addressed less in the landslide community. The Cima Salti Landslide in the Lake Garda region of Northern Italy is a cautionary tale of assuming source areas and volumes. It was traditionally thought to have dammed Tenno Lake in the Middle Ages, and to have a volume of 20–30 Mm3. We show through geological field data and simple runout simulations with the codes DAN3D and SHALTOP (which produced comparable results) that the volume of the landslide was likely significantly overestimated in the past, and that it most likely did not dam Tenno Lake, as has been assumed. We propose that a smaller volume landslide (2–5 Mm3) was deposited on stagnant ice melting in situ in the Lateglacial period, a relatively minor event in the complex history of the Magnone valley. This interpretation emphasizes the importance of careful field investigations and assumption validation, at Cima Salti and in a broader context. It also shows the unique capacity of landslide simulation to guide field observation and discriminate mass emplacement processes.File | Dimensione | Formato | |
---|---|---|---|
Tenno paper.pdf
solo gestori archivio
Descrizione: Versione dell'editore
Tipologia:
Full text (versione editoriale)
Licenza:
NON PUBBLICO - Accesso privato/ristretto
Dimensione
6.02 MB
Formato
Adobe PDF
|
6.02 MB | Adobe PDF | Visualizza/Apri Richiedi una copia |
pre-print Tenno.pdf
accesso aperto
Descrizione: Accepted manuscript
Tipologia:
Post-print
Licenza:
Creative commons
Dimensione
19.31 MB
Formato
Adobe PDF
|
19.31 MB | Adobe PDF | Visualizza/Apri |
Proof_GEOMOR_6384.pdf
accesso aperto
Descrizione: Uncorrected proof
Tipologia:
Post-print
Licenza:
Creative commons
Dimensione
5.98 MB
Formato
Adobe PDF
|
5.98 MB | Adobe PDF | Visualizza/Apri |
I documenti in SFERA sono protetti da copyright e tutti i diritti sono riservati, salvo diversa indicazione.