In the hierarchical approach of constitutive modelling, the damage accumulation and resulting strain-softening behavior of geologic materials can be modelled by introducing a concept of damage evaluation. The damage accumulation and softening behavior are affected by the size of specimens. A series of uniaxial tests on cylindrical specimens of a simulated rock were performed. The effect of specimen size on the parameters of the damage model were investigated by using the test results. The empirical results show that the damage parameters can be related to a characteristic dimension, which was expressed in terms of length and diameter of the specimen.

The unique Selukwe Subchamber of the Great Dyke is bounded by the Shurugwi greenstone belt (SGB) on the west side for approximately 25 km and granitoids on the east side, as compared to other subchambers of the Great Dyke that are bounded on both sides by granitoids. It is also the narrowest section of the entire Great Dyke. The extensive xenolith suite is found on the western flank and the central zone of the subchamber. This study focuses on the PAR 11 borehole and the surface xenoliths in the Selukwe Subchamber (SSC). The PAR 11 core was drilled into an anomalous sequence of ultramafic rocks situated in the Mafic Succession of the SSC. There are basically two rock types in the PAR 11 borehole: peridotites and pyroxenites. Comparison of the major and trace element geochemistry of the PAR 11 body with the MR 92 data of Coghill (1994) for the SSC reveals that they are similar but less evolved. The mineral assemblages and proportions of phases in the PAR 11 borehole samples are indicative of essentially the same composition as that which formed the layered sequence of the Great Dyke. Therefore, on the basis of the rock types and chemical compositions, the PAR 11 body and the Great Dyke cumulates appear to be petrologically and chemically similar and had the same petrogenesis. There are three rock types in the xenolith suite that have been observed in the mafic succession of the Unki area: peridotites, pyroxenites and gabbros. Major and trace elements show a wide range of compositions that have CaO/Al2O3 ~ 1, which are dissimilar to both PAR 11 and MR 92 borehole data. REE patterns show depletion of LREE, with flat HREEs indicating a different magma to that which gave rise to the Great Dyke. Such flat patterns are typical of a primitive mantle source similar to that of komatiite magma. Stowe, (1974) describes dunite and chromite in the SGB and does not describe pyroxenites and gabbros. Therefore, it is not clear in the first instance that the xenoliths were derived from the SGB. It also does not necessarily mean that these rock types did not occur in the SGB and, if they did, maybe they were derived from an intrusion within the SGB that is at depth and never been seen iv before. The xenoliths do not have mineral compositions that are similar to the Great Dyke and therefore precludes them as having been derived from the Great Dyke Marginal Facies, a possible source of such rocks. Therefore, it is concluded from this study that they were inherited from another source which also does not appear to be the SGB because there is no report of such rock types (other than peridotite) in the SGB. They are also not mantle derived. The metasedimentary rocks that occur as xenoliths are banded iron formation and quartzites and are all clearly derived from the different formations of the SGB. The quartzites are from the Mont d’Or Formation and Wanderer Formation. The BIFs are from the Upper Greenstone and Wanderer Formation. The Shurugwi Greenstones were stripped off from the western flank whereas the Archean granitoids to the eastern flank of the Great Dyke remained. The conclusion from this study is that the Shurugwi greenstones and Archean granitoids of the Selukwe area were intruded by the large volume of new magma that was the parental magma to the Great Dyke. The hot parental magma carried up with it xenoliths from outside the Great Dyke and large blocks from within the Great Dyke to the uppermost rocks of the level of the P1 pyroxenite layer and mafic unit.

A dissertation submitted for the degree of Master of Science School of Computer Science University of the Witwatersrand. Johannesburg, 2015. / Rock art is the archaeological term used to describe pre-historic artworks placed on natural stone and as one of the earliest known traces of modern human creativity, it is a major component of world history and human heritage. Archival records and the art itself, however, are rapidly decaying requiring the need to preserve them for future generations and humanity as a whole. In line with this, the Rock Art Research Institute digitised their collections of photographs and historical records of the rock art in southern Africa. This has resulted in the South African Rock Art Digital Archive, a collection of over 275 000 images of paintings depicting a wide variety of objects such as humans and animals. The problem with this archive, however, is that most of the images are not labelled with the objects that appear in them. Manual labelling is infeasible due to the size of the archive but rock art researchers require this information to perform text-based search queries. Therefore, in this research, we present the combination of the Viola Jones object detection framework and a Support Vector Machine to automatically classify rock art objects. To test it, we have created and assessed the performance of classi ers for eland, elephant, human, and rhebuck rock art objects. We have performed the experiments using ve-fold cross-validation and found the results to be promising considering the variation and deterioration of the paintings.

Thesis (doctoral)--Eidgenössische Technische Hochschule Zürich, 1982. / Summary in German. Vita. Includes bibliographical references (p. 243-260).

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Thesis (M. Sc.)--University of Canterbury, 2007. / Typescript (photocopy). Includes bibliographical references (leaves 190-202). Also available via the World Wide Web.

Thesis (Ph. D.)--University of Adelaide, Dept. of Geology and Geophysics, 1987. / Typescript. Maps in back pocket of v. 1. Microfiches in back pocket of v. 2. Microfiches contain petrographic descriptions, total rock XRF analyses and microprobe analyses. Includes bibliographical references (leaves 160-183 (v. 2)).

Thesis (Ph. D.)--University of Chicago, Dept. of the Geophysical Sciences, August 1999. / Includes bibliographical references. Also available on the Internet.