Triggering and runout conditions of two rock slope failures in the French Alps: Vallon d’Étache and Crête des Grangettes ...

• Main Authors: Cathala, Maëva, Magnin, Florence, Ravanel, Ludovic, Bock, Josué, Ben Asher, Matan, Revil, André, Faug, Thierry, Chambon, Guillaume, Josnin, Jean-Yves, Génuite, Kim, Richard, Jessy, Deline, Philip
• Format: Conference Object
• Language: unknown
• Published: GFZ German Research Centre for Geosciences 2023
• Subjects: Ice; permafrost
• Online Access: https://dx.doi.org/10.57757/iugg23-1906; https://gfzpublic.gfz-potsdam.de/pubman/item/item_5017671

<!--!introduction!--> In high mountains environments, permafrost degradation causes rockwall instabilities, sometimes leading to rock slope failures. These processes could be a threat for human lives and activities, it is therefore essential to improve our knowledge about their triggering and propagation mechanisms. This study focuses on two rock slope failures which occured in the Vallon d'Étache (Maurienne Valley, France) and the Crête des Grangettes (Écrins massif, France) in 2020. These events have respectively volumes around 270 000 m 3 and 35 000 m 3 . In both cases, ice in the rockfall scars suggests the presence of permafrost, but its local distribution and its role in the triggering of the events remain to be confirmed. The aims of this study are (i) to assess thermal conditions in which both events were triggered and (ii) to model their propagation. To do so, we first propose a method that combines rockwalls temperature monitoring, statistical modelling of permafrost distribution, geophysical ... : The 28th IUGG General Assembly (IUGG2023) (Berlin 2023) ...