Simulating fluid injection in geological media with complex rheologies

[摘要] Stimulation of geothermal systems by injection of water into wells at high pressures to create fractures and increase permeability of rocks is a widely used technique. Therefore, increasing our understanding about how such actions influence the local state of stress of the reservoir and how fractures propagate through it is necessary to efficiently develop extraction projects and, hopefully, to avoid undesired side effects. Advances in numerical modelling of hydraulic fracturing are thus required. To that end, we improved the modelling and solving capabilities of the software LaMEM by adding plasticity, poro-elasticity and Darcy flow making this code capable of simulate dilatant materials, accounting by the angle of dilatation, and reproduce shear/tensile failures due to local pore pressure increase. This improvement offers us an efficient computational massively-parallel code to model fluid injection and crack propagation in poro-visco-elasto-plastic rocks. Here we give examples of such model.

[发布机构] Geophysics Department, Johannes Gutenberg University of Mainz, Johann-Joachim-Becher-Weg 21, Mainz; 55128, Germany^1

[关键词] Elasto-plastic;Fluid injections;Geological media;Geothermal systems;High pressure;Massively parallels;Poro-elasticity;Pressure increase