Investigation of porosity and permeability effects from microstructure changes during limestone dissolution

International audienceWe studied experimentally the dissolution of a porous limestone core during CO2-enriched water injection. We measured the changes in porosity and permeability arising from modifications of the pore network geometry and the fluid-rock interface. A methodology based on periodic X-ray microtomography imaging was implemented to record the evolution of the time- and scale-dependent microstructures with a spatial resolution of 4.91 μm. Two processes were successively involved in the rapid permeability increase of the sample, as documented from microscale to core-scale measurements..