The broad aim of the proposal GEOGRAF is to develop a general understanding of granular flow rheology that will underpin truly predictive models for landslide dynamics. The main objective is to explore and further develop a promising rheology, recently established for idealized granular materials, in situations relevant to large-scale geophysical systems, including flows over complex topography and different grain sizes. The physical processes controlling the mobility of granular flows are investigated, as well as the application of continuum simulation tool to test the performances of rheological models and continuum modeling.The project prescribes the use of different and complementary methodologies, with state-of-the-art techniques in laboratory experiments, numerical modeling and geological fieldwork, combined to significantly enhance our understanding of the propagation of geophysical granular flows in the prospect of new predictive models for landslide hazards and risk assessment.The project is timely, combining recent advances from the perspectives of fundamental mechanics and geological observations, with a strong research team, well-equipped to make progress at the interface of these disciplines. The project will provide world-class research training for a mid-career theoretical physicist to learn experimental, numerical and geological fieldwork skills in a world-leading research institution; this will help the researcher establishing a position of professional maturity, and promote a long-term research collaboration.