Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references (leaves 99-101). Available also in a digital version from Dissertation Abstracts.

Thesis (Honors)--College of William and Mary, 2009. / Includes bibliographical references (leaves 59-61). Also available via the World Wide Web.

Thesis (Ph. D.)--University of Texas at Austin, 2000. / Vita. Includes bibliographical references.

Thesis (M.S.)--University of Missouri, School of Mines and Metallurgy, 1931. / The entire thesis text is included in file. Typescript. Title from title screen of thesis/dissertation PDF file (viewed December 14, 2009) Includes bibliographical references (p. 75).

Thesis (Ph.D.)--Memorial University of Newfoundland, 2002. / Bibliography: leaves R1-R38. Also available online.

Thesis (M.S.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xvii, 103 p. : ill. (some col.), maps. Includes abstract. Includes bibliographical references (p. 52-55).

Thesis (Ph. D.)--West Virginia University, 2003. / Title from document title page. Document formatted into pages; contains xi, 191 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 137-139).

The South China Craton comprises the Yangtze Block in the northwest and Cathaysia Block in the southeast. Located in the southeastern Yangtze Block, the Jiangnan Orogen formed through the amalgamation between the Yangtze and Cathaysia Blocks. The Yangtze Block has sporadically exposed Archean rocks in the north, Paleoproterozoic to Mesoproterozoic volcano-sedimentary sequences in the southwest and widespread Neoproterozoic sedimentary sequences accompanied by syn-sedimentary igneous rocks on the western and southeastern margins. The late Paleoproterozoic to early Mesoproterozoic Dongchuan, Dahongshan and Hekou groups in the southwestern Yangtze Block formed in a series of fault-controlled, rift-related basins associated with the fragmentation of the supercontinent Columbia. These sedimentary sequences were deposited between 1742 and 1503 Ma, and recorded continuous deposition from alluvial fan and fluvial sedimentation during the initial rifting to deep marine sedimentation in a passive margin setting. Sedimentation during initial rifting received felsic detritus mainly from adjacent continents, whereas sedimentation in a passive margin basin received detritus from felsic to intermediate rocks of the Yangtze Block. Paleoproterozoic to Mesoproterozoic rift basins in the southwestern Yangtze Block are remarkably similar to those of north Australia and northwestern Laurentia in their lower part (1742-1600 Ma), but significantly different after ca. 1600 Ma. The southwestern Yangtze Block was likely connected with the north Australia and northwestern Laurentia in Columbia but drifted away from these continents after ca. 1600 Ma. Traditionally thought Mesoproterozoic sedimentary sequences in the southeastern Yangtze Block are now confirmed to be Neoproterozoic in age and include the 835-830 Ma Sibao, Fanjingshan and Lengjiaxi groups, and 831-815 Ma Shuangqiaoshan and Xikou groups. These sequences are unconformably overlain by the ~810-730 Ma Danzhou, Xiajiang, Banxi, Heshangzheng, Luokedong and Likou groups. The regional unconformity likely marked the amalgamation between the Yangtze and Cathaysia Blocks and thus occurred at ~815-810 Ma. The lower sequences (835-815 Ma) received dominant Neoproterozoic (~980-820) felsic to intermediate materials in an active tectonic setting related to continental arc and orogenic collision, whereas the upper sequences represent sedimentation in an extensional setting with input of dominant Neoproterozoic granitic to dioritic materials (~740-900 Ma). The upper parts of the Shuangqiaoshan and Xikou groups, uncomfortably underlain by lower units, are molasse-type assemblages with additional input of pre-Neoproterozoic detritus, representing accumulation of sediments in a retro-arc foreland basin associated with the formation of the Jiangnan Orogen. Stratigraphic correlation, similarly low-δ18O and tectonic affinity of igneous rocks from different continents suggest that the Yangtze Block should be placed in the periphery of Rodinia probably adjacent to northern India. Paleoproterozoic (~2480 Ma and ~2000 Ma) and Early Neoproterozoic (711-997 Ma) were the most important periods of crustal and magmatic events of the southeastern Yangtze Block, but there is a lack of significant Grenvillian magmatism. Early Neoproterozoic magmatism highlights the contribution from both juvenile materials and pre-existing old crust, whereas ~2480 Ma and ~2000 Ma events are marked by reworking of pre-existing continental crust. Magmatism at 1600-1900 Ma was dominated by reworking of pre-existing crust, whereas the 1400-1600 Ma magmatic event recorded some addition of juvenile materials. / published_or_final_version / Earth Sciences / Doctoral / Doctor of Philosophy

Spatial correlation functions, which quantify spatial relationships among porphyroblasts over a range of length scales, can be used in combination with other techniques of quantitative textural analysis to constrain crystallization mechanisms in metamorphic rocks. The utility, reliability, and robustness of these functions, however, depend critically upon correct methods of calculation and application to geological samples. Application of the L' -function, Pair Correlation Function, and Mark Correlation Function (Stoyan and Stoyan, 1994) to artificial arrangements of crystals yields results consistent with their predetermined ordering and clustering qualities. These results serve as a foundation for the interpretation of more complex simulated and natural crystal arrays. Analysis of artificial and simulated crystal arrays in which ordering signals are obscured in various ways (displacing crystals in an ordered array by increasing amounts, reducing the number of crystals, and increasing the sample's aspect ratio) demonstrates that these scale-dependent functions are robust indicators of effects diagnostic of certain crystallization mechanisms, even in complex circumstances. The effects of clustering of nucleation sites, however, can strongly obscure any underlying signal that might reveal crystallization mechanisms. The L' -function and the Pair Correlation Function are sensitive to short-range ordering of crystals, which may reflect suppression of nucleation in the vicinity of growing porphyroblasts. The Mark Correlation Function is sensitive to size-isolation correlations, which may reflect retardation of growth among crystals competing for nutrients. Interpretation of these functions, however, requires careful attention to proper calculation of Monte Carlo simulations, which are used to identify values of the functions that constitute a null-hypothesis region for comparison to samples with unknown ordering and clustering characteristics. To yield functional values commensurate with those calculated for a particular natural rock specimen, each simulation must match as closely as possible several critical features of the natural rock, including the set of crystal radii, limitations on the observability of crystals, and the shape and size of the bounding surface of the sample. Crystallization mechanisms in seven previously studied garnetiferous rocks from three localities (Carlson et al., 1995; Denison and Carlson, 1997) have been re-assessed using both scale-dependent correlation functions and single-valued spatial statistics, both evaluated by comparison to rigorously computed null-hypothesis regions. The results confirm previous inferences that the nucleation and growth rates of the garnet porphyroblasts in these specimens were governed by rates of diffusion through the intergranular medium. / text

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