Abstract

Summary We assume that permeability in crystalline rocks is mainly controlled by interconnected cracks. Following Dienes (1982), statistical distributions of cracks are introduced (crack aperture and radius distributions, spatial distribution). Percolation theory is used to describe the interconnection of cracks. At first, we assume that cracks are smooth and close elastically under pressure. In that case, permeability evolution results from both variations of crack aperture and interconnection. In a second step, crack roughness is taken into account: when asperities of rough-walled cracks make contact, the evolution of cracks is controlled by asperities indentation. Two different possibilities are then considered: modification of the flow tortuosity or modification of the crack aperture. Calculations are performed for both of these situations and we compare theoretical models with experimental results. It appears that the tortuosity effect is negligible and that the second model gives the best results and describes well the permeability decrease. Values of microstructural parameters introduced are realistic, so that it seems possible to predict the permeability evolution from the observation of microstructural parameters.

Full Text
Paper version not known

Talk to us

Join us for a 30 min session where you can share your feedback and ask us any queries you have

Schedule a call

Disclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.