High temperature deformation mechanisms and strain heterogeneities in calcite rocks
Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2008.
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| Format: | Thesis |
| Language: | eng |
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Massachusetts Institute of Technology
2009
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| Online Access: | http://hdl.handle.net/1721.1/45602 |
| _version_ | 1811091116550782976 |
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| author | Xu, Lili, Sh. D. Massachusetts Institute of Technology |
| author2 | J. Brian Evans. |
| author_facet | J. Brian Evans. Xu, Lili, Sh. D. Massachusetts Institute of Technology |
| author_sort | Xu, Lili, Sh. D. Massachusetts Institute of Technology |
| collection | MIT |
| description | Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2008. |
| first_indexed | 2024-09-23T14:57:17Z |
| format | Thesis |
| id | mit-1721.1/45602 |
| institution | Massachusetts Institute of Technology |
| language | eng |
| last_indexed | 2024-09-23T14:57:17Z |
| publishDate | 2009 |
| publisher | Massachusetts Institute of Technology |
| record_format | dspace |
| spelling | mit-1721.1/456022019-04-10T09:16:26Z High temperature deformation mechanisms and strain heterogeneities in calcite rocks Xu, Lili, Sh. D. Massachusetts Institute of Technology J. Brian Evans. Massachusetts Institute of Technology. Dept. of Earth, Atmospheric, and Planetary Sciences. Massachusetts Institute of Technology. Dept. of Earth, Atmospheric, and Planetary Sciences. Earth, Atmospheric, and Planetary Sciences. Thesis (Ph. D.)--Massachusetts Institute of Technology, Dept. of Earth, Atmospheric, and Planetary Sciences, 2008. This electronic version was submitted by the student author. The certified thesis is available in the Institute Archives and Special Collections. Page 238 blank. Includes bibliographical references. In nature, carbonates often accumulate large amounts of strain in localized shear zones. Such marble sequences play a key role in crustal deformation processes. Despite extensive field and laboratory investigation, many questions remain concerning the mechanical behavior of these rocks. For example, the mechanical behavior of different limestones and marbles differ greatly, possibly owing to the presence of chemical impurities or solid-solutes. Thus, Chapter 2 examines the effect of Mg solute, a common impurity, on the mechanical behavior of calcite rocks. The results indicate that increasing Mg content increases the strength of calcite rocks during dislocation creep. The anisotropic nature of crystal slip usually entails variations in reorientation of individual grains and heterogeneous deformation within the polycrystalline material. In Chapter 3, a new technique including a series of sample preparation and image analysis algorithms is developed to provide quantitative measurements of the scale of heterogeneities produced, and to gain fundamental insight into polycrystalline plasticity. We place particular attention on quantifying variations of strain within grain interiors and at grain boundaries, and on recognizing the relative activities of different slip systems. The quantification of grain-to-grain interactions during straining is relevant for the improvement and verification of models of polycrystalline plasticity. The strain measurements obtained from Chapter 3 are compared with predictions of grain strain and reorientation obtained from the self-consistent viscoplastic method (Chapter 4). The results suggest that the self-consistent model gives a good description of global texture, but does not always predict lattice rotation and deformation within individual grains. To predict the actual deformation of individual grains will require a quantitative consideration of the effects on local strain of grain-boundary misorientation, local strain/stress state, grain-boundary sliding, and deviations in grain geometry. by Lili Xu. Ph.D. 2009-06-25T20:33:31Z 2009-06-25T20:33:31Z 2008 2008 Thesis http://hdl.handle.net/1721.1/45602 318453113 eng M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission. http://dspace.mit.edu/handle/1721.1/7582 238 p. application/pdf Massachusetts Institute of Technology |
| spellingShingle | Earth, Atmospheric, and Planetary Sciences. Xu, Lili, Sh. D. Massachusetts Institute of Technology High temperature deformation mechanisms and strain heterogeneities in calcite rocks |
| title | High temperature deformation mechanisms and strain heterogeneities in calcite rocks |
| title_full | High temperature deformation mechanisms and strain heterogeneities in calcite rocks |
| title_fullStr | High temperature deformation mechanisms and strain heterogeneities in calcite rocks |
| title_full_unstemmed | High temperature deformation mechanisms and strain heterogeneities in calcite rocks |
| title_short | High temperature deformation mechanisms and strain heterogeneities in calcite rocks |
| title_sort | high temperature deformation mechanisms and strain heterogeneities in calcite rocks |
| topic | Earth, Atmospheric, and Planetary Sciences. |
| url | http://hdl.handle.net/1721.1/45602 |
| work_keys_str_mv | AT xulilishdmassachusettsinstituteoftechnology hightemperaturedeformationmechanismsandstrainheterogeneitiesincalciterocks |