Session VI details: Fluids and Deformations

Conveners: Stephen Miller (U Bonn), Marcos Moreno Switt (GFZ)
Keynote Speakers:

  • Boris Galvan (U Bonn): Towards a general simulation tool for complex fluid-rock lithospheric processes: merging pre-processing, processing and post-processing in state-of-the-art computational devices
  • Takeshi Tsuji (U Kyushu): Digital rock physics: Insight into fluid flow and elastic deformation of porous media

This session is focused on the interactions between elastic and inelastic deformation, brittle failure (earthquakes), how fluids affect and are affected by, coupled deformation, as well as the importance of flow for numerous geodynamic processes. These include, but are not limited to, non-volcanic tremor and slow-slip earthquakes, enhanced geothermal systems, post-seismic deformation, earthquake swarms, and aftershocks. Although the interactions between fluids and deformation are conceptually straightforward, complexity arises due to multiple feedbacks between crack nucleation, growth, and coalescence combined with the initiation of fluid flow and an evolving pore-elastic/ fracture stress state. Modelling these processes is numerically challenging because the underlying physics require high-resolution simulations over a wide range of timescales. This session aims to understand fluids and deformation of a wide range of space and time scales, using recent advances in numerical modelling to compare with observations from experimentalists, geodesists, and geologists.

 

The figure shows the results of a numerical experiment of high pressure fluid injection at a borehole into a pore-elastic plastic rheology-coupled to non-linear diffusion and calculated on the Graphics Processing Unit (GPU) architecture (Galvan 2012). The top row shows the evolution of numerical fractures forming in response to the applied stress at the boundaries and the evolving stress state due to crack interaction and pore-elastic stresses. The bottom row shows the evolution of the pore pressure within the numerical specimen.