The gravitational slope deformation of Mt. Rocchetta ridge (central Apennines, Italy): geological-evolutionary model and numerical analysis

This paper presents the results of a study on a deep-seated gravitational slope deformation affecting the eastern slope of the Mt. Rocchetta ridge (central Apennines, Italy). Fieldwork identified the ongoing deformational process and assisted in defining its mechanisms, evolution and controlling factors. An equivalent continuum approach was adopted to characterize the rock mass with some modification for the temporal and spatial scale of the process. A visco-elastic-plastic rheological model was adopted for the numerical analysis, which also took into account the groundwater flow feeding the Capo Volturno spring. The results of the numerical analysis are consistent with the observed geomorphic evidence and suggest a morpho-evolutionary model of the ridge characterized by an initial phase of rock mass creep followed by a rock mass spreading process, mainly controlled by the viscous behaviour but with a significant contribution from groundwater for the smaller scale instabilities.