Structural and geomorphological framework of the upper Maira Valley (Western Alps, Italy): the case study of the Gollone Landslide

Abstract

An interdisciplinary study has been adopted to investigate the upper Maira Valley (Western Alps, Italy). A geological map of an unmapped area, of about 12 km2, at scale 1:10.000, has been realized. The combination of field surveys, GIS database creation, aerial photo observation, local archival data consultation, geo-structural analysis and drillholes re-interpretation outlined a relationship between structures and landforms. A ductile and brittle deformation history with the definition of four discontinuity systems (F1-F4) has been detected. Where the fracturation is intense, rock-falls and topplings are triggered. In area associated with a homogeneous presence of weathered cover, debris flows were identified. The geo-structural pattern obtained from the surveys in the upper Maira Valley allowed characterizing detachment zones of the slope overlooking Acceglio town. The Gollone Landslide is an excellent case study to unravel the structural-morphological interaction and the kinematic evolution due to its framework.

Keywords

• structural survey
• geological mapping
• gis
• geomorphology
• landslide hazard