Session Themes > Session 5 - Fluids, grains, soils and avalanches/instabilities

Convener: R. Toussaint, JL Vinningand

Fluids, grains, soils and avalanches/instabilities

Conveners: R. Toussaint, CNRS/University of Strasbourg,  J.L. Vinningand, I.R.I.S., Stavanger

Keynote Speaker:

Bjornar Sandnes, University of Swansea

In many contexts in Earth Science, mechanical processes involve the deformation of granular materials and fluids. Deep in the crust, fault gouges are often filled with one or several fluids that play a role on the friction at the heart of seismic activity. In the shallower crust, volcanic eruptions are related to degassing and transport of solid materials. High pore pressures can generate mud-volcanoes, pockmarks, liquefaction along wells, variability of sealed boundaries possibly leading to injectite formation... Close to the surface, the dynamics of soils can be affected by the transport of fluid and the associated viscous forces, the presence of fluids of diffferent densities that can affect buoyancy and modify the solid stress, and the presence of two fluid interfaces that can affect the cohesion properties. Avalanches, liquefaction and sudden eruptions can result from the mechanical instabilities associated to these phenomena. They also oftern display non trivial pattern formation that can help to recognize or monitor tem, and that affect the transport properties of the confined deformable divided solid assemblies at play.

In this session, we welcome experimental, numerical, theoretical and field-based works related to these phenomena, with posible contributions from the communities of granular physics, fluid mechanics, geophysics, hydrology, geomorphology and Earth Science.