| The traditional quantitative texture analysis approach, which has relied on pole figure measurements with monochromatic X-ray or neutron diffraction, is not efficient for polymineralic rocks and low symmetry minerals, where there are often closely spaced and partially or completely overlapped diffraction peaks. A new approach, the Rietveld Texture Analysis or RTA, has recently been proposed. This method is based on the Rietveld and the polychromatic Time-of-Flight (TOF) neutron diffraction techniques, in which the texture information is evaluated, through iterations, from a large number of complete diffraction patterns, rather than a few separate peaks. This thesis work is the first application of the method to multiphase (e.g. eclogite), low-symmetry (e.g. plagioclase), and archaeological (e.g. ancient coins) materials. Its reliability in these complex materials is investigated.; Textures were measured by TOF neutron diffraction and analyzed with the RTA method. In addition, the SEM-EBSD technique was applied to the same samples of eclogite and plagioclase. Consistent results are obtained from both techniques. For the coins, the non-destructive requirement prevented them from additional SEM-EBSD analysis, yet the texture results were compared between two analytical computer programs MAUD (Material Analysis Using Diffraction) and GSAS (General Structure Analysis System). The results given by these two programs are in good agreement.; The study demonstrates that complex geological materials are amenable to this new quantitative texture analysis approach. This method is likely to add to a better understanding of deformation in complex geological materials. A combination of this method with the non-destructive TOF neutron diffraction measurement provides an appropriate tool for the characterization of archaeological objects.; As a secondary goal of the study, the advantages and limitations of the two modern experimental techniques, TOF neutron diffraction and SEM-EBSD, are explored and highlighted in the work. In particular, the ability of measuring bulk samples and the non-destructive nature of neutron diffraction, as well as the statistical relevance of individual orientation measurements of SEM-EBSD are emphasized. |
