|MadSci Network: Physics|
Carl: The answer to this question is quite complex, and there isn't any one formula that will give it to you. The rates at which fluids move through pore networks depend on the sizes of the smaller openings in the pore networks (the pore throats), the physicochemical characteristics of the matrix material, the complexity of paths that the fluids must follow, and the viscocity and surface characteristics of the fluids. This type of question is usually studied empirically using capillary-pressure apparatus, and a fair amount of data on chalks have been published in the technical literature. You can do a search on capillary pressure, chalk, carbonate, etc. in the database called GeoRef (see your nearest university science library) and get many references. Some of the papers are probably online, so a similar search of the Internet would probably be productive. I have done a little research on capillary-pressure characteristics of chalks and other carbonates myself (see references) and I can tell you that they vary by orders of magnitude in their ability to transmit fluids. Movement of fluids through wood and ceramic involves the same issues, but the details are very different, and I am not familiar with the literature on these substances. And internet search might be a good way to start, and the nearest materials sciences department at a university would probably help with finding studies of ceramics. David Kopaska-Merkel Geological Survey of Alabama P.O. Box 869999 Tuscaloosa AL 35486-6999 (205) 349-2852 fax (205) 349-2861 www.gsa.state.al.us REFERENCES ON CAPILLARY PRESSURE 7. Kopaska-Merkel, D. C. and Amthor, J. E., 1988, Very high-pressure mercury porosimetry as a tool in reservoir characterization: Carbonates and Evaporites, v. 3, no. 1, p. 53-63. 8. Amthor, J. E., Kopaska-Merkel, D. C., and Friedman, G. M., 1988, Reservoir characterization, porosity, and recovery efficiency of deeply-buried Paleozoic carbonates: Oklahoma and Texas, Carbonates and Evaporites, v. 3, no. 1, p. 33-52. 11. Kopaska-Merkel, D. C., 1988, New applications in the study of porous media: determinations of pore-system characteristics on small fragments (Part 1): Northeastern Environmental Science, v. 7, p. 127-142. 12. Kopaska-Merkel, D. C., 1989, Supplementary data on applications of the study of small fragments of porous media: Northeastern Science Foundation Technical Report No. 2. Troy, Northeastern Science Foundation, 24 p. 15. Kopaska-Merkel, D. C. and Friedman, G. M., 1989, Petrofacies analysis of carbonate rocks: example from the Lower Paleozoic Hunton Group of Oklahoma and Texas: American Association of Petroleum Geologists Bulletin, v. 73, p. 1289-1306. 16. Kopaska-Merkel, D. C. and Friedman, G. M., 1989, Supplementary data to "Petrofacies analysis of carbonate rocks: example from the Lower Paleozoic Hunton Group of Oklahoma and Texas": Carbonates and Evaporites, v. 4, p. 243-245. 20. Kopaska-Merkel, D.C., 1990, Capillary-pressure analysis of small fragments (geological): The microReport, v. 1, no. 2, p. 5-6. 22. Kopaska-Merkel, D.C., 1991, Analytical procedure and experimental design for geological analysis of reservoir heterogeneity using mercury porosimetry: Geological Survey of Alabama Circular 153, 29 p. THIS IS THE ONE ON CHALK: 28. Kopaska-Merkel, D.C., 1992, Chapter 6: Capillary-pressure characteristics and pore-system evolution of Mesozoic and Tertiary carbonates from the Exmouth Plateau and the Argo and Gascoyne abyssal plains: p. 137-150 in, Gradstein, Felix, and Ludden, John, and others, Scientific Results of the Ocean Drilling Program, vol. 123. 33. Kopaska-Merkel, D. C., 1993, Capillary-pressure characteristics of Smackover reservoirs in Alabama: Geological Survey of Alabama Circular 170, 38 p.
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