Optical methods for determining the porosity and permeability of sandstones /
An optical method has been devised for determining the permeability (single-phase) and porosity, as well as the grain size of sandstones utilizing the principle of total internal reflection (TIR) of light. TIR occurs due to the difference of refractive indices (n) between two media; in this case, t...
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| Format: | Thesis Book |
| Language: | English |
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[Place of publication not identified] :
[publisher not identified] ;
1997.
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| Online Access: | http://proxy.library.tamu.edu/login?url=http://proquest.umi.com/pqdweb?did=736580641&sid=1&Fmt=2&clientId=2945&RQT=309&VName=PQD |
| Summary: | An optical method has been devised for determining the permeability (single-phase) and porosity, as well as the grain size of sandstones utilizing the principle of total internal reflection (TIR) of light. TIR occurs due to the difference of refractive indices (n) between two media; in this case, the quartz grains (n @ 1.53) which are abundant in sandstones and a liquid which saturated all the sandstone samples, Mono-Isopropyl Biphenyl (MIB, n = 1.57). This was achieved by placing 'thick' rock sections (as opposed to thin sections used in optical microscopy), 5 mm thick and saturated with MIB, between an infrared source-detector system and measuring the resulting light output. The light output was due to the scattering and refraction of light through the transparent quartz grains, and by TIR of light from the boundaries of the grains, through the pore spaces of the sandstone sample. The purpose of this experiment was to establish a relationship between the light output and the internal pore structure of the sandstone samples, using one fixed wavelength (i.e. lym) as a platform for future studies utilizing many different wavelengths in the infrared range. For sandstones of moderate porosity and moderate to high permeability, a good correlation was observed between the grain size distribution and light output while the correlation with porosity and permeability was dominated by the amount of quartz and their size in the samples. Predicting the internal structure of sandstones by this method could provide a useful and quick method in laboratory sampling of some porous materials as well as a promising approach in the development of a well logging device. |
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| Item Description: | Vita. "Major Subject: Geophysics". |
| Physical Description: | xii, 97 leaves : illustrations ; 28 cm. Issued also on microfiche from University Microfilms Inc. |
| Bibliography: | Includes bibliographical references: pages 71-73. |