Investigating the Permeability Evolution of Artificial Rock During Ductile and Brittle Deformation Under Pressurized Flow

TL;DR

This study introduces an artificial rock model to experimentally investigate how ductile and brittle deformation under pressurized flow influence permeability, providing insights relevant for geothermal energy and CO2 sequestration.

Contribution

It develops a controllable artificial rock that mimics real rock behavior, enabling experimental analysis of permeability evolution during deformation under pressurized flow.

Findings

Permeability changes correlate with ductile and brittle deformation modes.

Artificial rock can simulate various rock types by adjusting sintering parameters.

The models effectively capture permeability evolution during deformation.

Abstract

The drilling of geothermal energy, CO2 sequestration, and wastewater injection all involve the pressurized flow of fluids through porous rock, which can cause deformation and fracture of the material. Despite the widespread use of these industrial methods, there is a lack of experimental data on the connection between the pore pressure rise, the deformation and permeability changes in real rock. In order to address this gap in the literature, this study developed an artificial rock material that can be deformed and fractured at low pressures. By controlling the porosity, permeability, and strength of the material during the sintering process, it is possible to mimic various types of rock. The artificial rock was designed to accommodate radial flow and deformation, allowing for the tracking of deformation by monitoring the flux and driving pressure and thus calculating the permeability changes under various pressure conditions. The study was able to examine the impact of both ductile and brittle deformation on the permeability during pressurized flow, which were captured by two models that were adjusted to this scenario. This study provides a link between pressurized flow, rock formation permeability and ductile to brittle deformation, that can constrain risk assessment to geothermal energy and CO2