Modelling of Earth and planetary surface processes from channel dynamics to erosion of landscapes has made good use of the continuum framework, rather than directly dealing with particle scale processes, partly because of the typical large scale of the problem. Experiments, field observations, and modelling have shown the dynamics of discrete particle interactions, sometimes referred to as ‘granular physics’, plays an important role in erosion, transport, deposition and more generally in the evolution of landscapes and hazard analysis.
In particular, segregation by size, density and other properties largely modifies fluxes and results in complex patterns observed in many geophysical flows and landscapes. Examples include in fluvial geomorphology, armouring, downstream fining and drastic change in bedload and suspended sediment transport ; in debris flows, the coarsening of the front and levees ; and in Aeolian transport the internal structure of dune fields. Segregation also plays a role in hazards associated with snow avalanches, pyroclastic flows, rock avalanches, gravity currents and other geomorphic flows.
This session welcomes experimental, theoretical, numerical and field-based contributions within different environments, including coasts, estuaries, rivers, mountains enhancing our understanding of granular processes as well as their upscaling into continuum-like frameworks able of representing large-scale systems.