Related Experiment Video
Updated: Jun 14, 2025

Reservoir Condition Pore-scale Imaging of Multiple Fluid Phases Using X-ray Microtomography
Published on: February 25, 2015
Permeability partitioning through the brittle-to-ductile transition and its implications for supercritical geothermal
Gabriel G Meyer1, Ghassan Shahin2, Benoît Cordonnier3
1Laboratory of Experimental Rock Mechanics, School of Architecture, Civil & Environmental Engineering, Ecole Polytechnique Fédérale de Lausanne, Lausanne, Switzerland. gabriel.meyer@epfl.ch.
Abstract:
Geothermal projects utilizing supercritical water (≥400 °C) could boost power output tenfold compared to conventional plants. However, these reservoirs commonly occur in crustal areas where rocks are semi-ductile or ductile, impeding large-scale fractures and cracking, and where hydraulic properties are largely unknown. Here, we explore the complex permeability of rocks under supercritical conditions using mechanical data from a gas-based triaxial apparatus, high-resolution synchrotron post-mortem 3D imagery, and finite element modeling. We report a first order control of strain partitioning on permeability. In the brittle regime, strain localizes on permeable faults without necessarily increasing sample apparent permeability. In the semi-ductile regime, distributed strain increases permeability both in deformation bands and the bulk, leading to a more than tenfold permeability increase. This study challenges the belief that the brittle-ductile transition (BDT) marks a cutoff for fluid circulation in the crust, demonstrating that permeability can develop in deforming semi-ductile rocks.
More Related Videos
Related Concept Videos
Stress-Strain Diagram - Brittle Materials
Permeability of Concrete
Transition Zone
Pore Size Distribution
Adequate...
Porosity in Cement Paste
The balance of water to cement in the mix is...
Phase Diagram

