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Detailed Reference Information |
Noiriel, C., Gouze, P. and Bernard, D. (2004). Investigation of porosity and permeability effects from microstructure changes during limestone dissolution. Geophysical Research Letters 31: doi: 10.1029/2004GL021572. issn: 0094-8276. |
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We 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 ¿m. Two processes were successively involved in the rapid permeability increase of the sample, as documented from microscale to core-scale measurements. First, the microcrystalline phase was partially dissolved, associated with displacement of mineral particles. During this process, the exponent n of the power law k ~ $phi$n decreased continuously. Secondly the sparitic phase dissolved, accompanied by a decrease of the pore wall roughness and an increase of the pore connectivity. This second period was characterized by a constant value of n. The reactive surface decreased noticeably during the transition from the microcrystalline to the sparitic dissolution periods, whereas the effective porosity increased strongly. |
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Abstract |
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Keywords
Geochemistry, Chemical evolution, Physical Properties of Rocks, Permeability and porosity, Physical Properties of Rocks, Microstructure, Physical Properties of Rocks, Transport properties, Physical Properties of Rocks, Instruments and techniques |
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Publisher
American Geophysical Union 2000 Florida Avenue N.W. Washington, D.C. 20009-1277 USA 1-202-462-6900 1-202-328-0566 service@agu.org |
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