Dissertations / Theses: 'Witwatersrand Supergroup (South Africa)'

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Bartman, R. D. (Reynard Dirk). "Geology of the Palaeoproterozoic Daspoort Formation (Pretoria Group, Transvaal Supergroup), South Africa." Diss., University of Pretoria, 2013. http://hdl.handle.net/2263/42447.

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This thesis examines the geology of the Daspoort Formation (Pretoria Group, Transvaal Supergroup) of South Africa, with the accent on describing and interpreting its sedimentology. The Palaeoproterozoic Daspoort Formation (c. 2.1‐2.2 Ga) forms part of the Pretoria Group on the Kaapvaal craton. This sandstone‐ and quartzite‐dominated lithological formation covers an elliptical geographical area stretching from the Botswana border in the west to the Drakensberg escarpment in the east, with its northern limit in the Mokopane (Potgietersrus) area and Pretoria in the south; altered outliers are also found in the overturned units of the Vredefort dome in the Potchefstroom area. Deposition of the Daspoort Formation was in a postulated intracratonic basin which applies equally to the entire Transvaal Supergroup succession in the Transvaal depository. Various characteristics from the formation, such as sedimentary architectural elements (e.g., channel–fills etc.), maturity trends and distribution of lithofacies assemblages across the preserved basin give insight into the developing conditions during deposition and genesis of the Daspoort Formation. Subordinate evidence from basic geochemistry, ripple mark data and optical microscope petrology studies support the sedimentary setting inferred for this Palaeoproterozoic deposit. Fluvial and epeiric marine conditions prevailed during the deposition of the Daspoort clastic sediments into the intracratonic basin. This shallow epeiric sea was fed by fluvial influx, predominantly from the west when a transgressive regional systems tract led to the filling of the basin, evolving into the deeper marine Silverton Formation setting, laid down above the Daspoort. Transgression from the east (marine facies predominate) to the west (fluvial facies) is supported by cyclical trends, palaeoenvironmental and palaeogeographical interpretations. Accompanying poorly preserved microbial mat features contribute to the postulated shallow marine environment envisaged for the eastern part of the basin whereas ripple marks and grain size distribution support a fluvial setting for the west, with lithofacies assemblages accounting for both areas’ depositional interpretation.
Dissertation (MSc)--University of Pretoria, 2013.
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2

Polteau, Stéphane. "Stratigraphy and geochemistry of the Makganyene formation, Transvaal supergroup, Northern Cape, South Africa." Thesis, Rhodes University, 2001. http://hdl.handle.net/10962/d1005616.

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The Makganyene Formation forms the base of the Postmasburg Group in the Transvaal Supergroup of the Northern Cape Province. The Makganyene Formation has diamictite as the main rock type, but siltstone, sandstone, shale, and iron-formations are also present. A glacial origin has been proposed in the past due to the presence of dropstones, faceted and striated pebbles. Typically, the Makganyene Formation contains banded iron-formations interbedded with clastic rocks (shale, siltstone, sandstone and diamictites) at the contact with the underlying iron-formations. This transitional zone is generally overlain by massive or layered diamictites which contain poorly sorted clasts (mainly chert) within a shaly matrix. Striated pebbles have been found during field work, and dropstones have been observed in diamictites and banded iron-formations during the study. The top of the Makganyene Formation contains graded cycles interbedded with diamictites and thin layers of andesitic lavas from the Ongeluk Formation. The basal contact of the Makganyene Formation with the underlying Koegas Subgroup was described as unconformable by previous workers. However field work localised in the Rooinekke area shows a broadly conformable and interbedded contact with the underlying Koegas Subgroup. As described above, banded iron-formations are interbedded with the clastic rocks of the Makganyene Formation. Moreover, boreholes from the Sishen area display the same interbedding at the base of the Makganyene Formation. This suggests that no significant time gap is present in the whole succession between the Ghaap and Postmasburg Group. The Transvaal Supergroup in the Northern Cape displays the following succession : carbonates-BIFs-diamictites/ lava-BIFs-carbonates. The Makganyene Formation is thus at the centre of a symmetrical lithologic succession. Bulk rock compositions show that the diamictites have a similar composition to banded iron-formation with regard to their major element contents. Banded iron-formations acted as a source for the diamictites with carbonates and igneous rocks representing minor components. Differences in bulk composition between the Sishen and Matsap areas emphasize that the source of the diamictite was very localised. The Chemical Index of Alteration (CIA) has been calculated, but since the source dominant rock was iron-formation, this index cannot be usefully applied to the diamictites. ACN, A-CN-K, and A-CNK-FM diagrams confer a major importance in sorting processes due to the separation between the fine and coarse diamictites. The interbedded iron-formations display little clastic contamination indicating deposition in clear water conditions. However, dropstones are present in one borehole from the Matsap area, indicating that iron-formation took place under ice cover, or at least under icebergs. Stable isotope studies show that the iron-formations, interbedded towards the base of the Makganyene Formation, have similar values to the iron-formations of the Koegas Subgroup. As a result of the above observations, new correlations are proposed in this study, relating the different Transvaal Supergroup basins located on the Kaapvaal Craton. The Pretoria Group of the Transvaal Basin has no correlative in the Griqualand West Basin, and the Postmasburg Group of the Northern Cape Basin has no lateral equivalent in the Transvaal Basin. These changes have been made to overcome problems present in the current correlations between those two basins. The Makganyene Formation correlates with the Huronian glaciations which occurred between 2.4 and 2.2 Ga ago in North America. Another Precambrian glaciation is the worldwide and well-studied Neoproterozoic glaciation (640 Ma). At each of these glaciations, major banded iron-formation deposition took place with associated deposition of sedimentary manganese in post-glacial positions. The central position of the Makganyene Formation within the Transvaal Supergroup in the Northern Cape emphasizes this glacial climatic dependence of paleoproterozoic banded iron-formation and manganese deposition. However these two Precambrian glaciations are interpreted in paleomagnetic studies as having occurred near to the equator. The controversial theory of the Snowball Earth has been proposed which proposes that the Earth was entirely frozen from pole to pole. Results from field work, sedimentology, petrography and geochemistry were integrated in a proposed depositional model of the Makganyene Formation occurring at the symmetrical centre of the lithologic succession of the Transvaal Supergroup. At the beginning of the Makganyene glaciation, a regression occurred and glacial advance took place. The diamictites are mostly interpreted as being deposited from wet-based glaciers, probably tidewater glaciers, where significant slumping and debris flows occurred. Any transgression would cause a glacial retreat by rapid calving, re-establishing the chemical sedimentation of banded iron-formations. These sea-level variations are responsible for the interbedding of these different types of rocks (clastic and chemical). The end of the Makganyene glacial event is characterised by subaerial eruptions of andesitic lava of the Ongeluk Formation bringing ashes into the basin. Banded iron-formation and associated manganese accumulations are climate-dependant. Glacial events are responsible for the build up of metallic ions such as iron and manganese in solution in deep waters. A warmer climate would induce a transgression and precipitation of these metallic ions when Eh conditions are favourable. In the Transvaal Supergroup, the climatic variations from warm to cold, and cold to warm are expressed by the lithologic succession. The warm climates are represented by carbonates. Cold climates are represented by banded iron-formations and the peak in cold climate represented by the diamictites of the Makganyene Formation. These changes in climate are gradual, which contradict the dramatic Snowball Earth event: a rapid spread of glaciated areas over low-latitudes freezing the Earth from pole-to-pole. Therefore, to explain low-latitude glaciations at sea-level, a high obliquity of the ecliptic is most likely to have occurred. This high obliquity of the ecliptic was acquired at 4.5 Ga when a giant impactor collided into the Earth to form the Moon. Above the critical value of 54° of the obliquity of the ecliptic, normal climatic zonation reverts, and glaciations will take place preferentially at low-latitudes only when favourable conditions are gathered (relative position ofthe continents and PC02 in the atmosphere).

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Kraak, Camille. "A provisional basin analysis of the Karoo Supergroup, Springbok Flats Basin, South Africa." Diss., University of Pretoria, 2014. http://hdl.handle.net/2263/45921.

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The Springbok Flats (SBF) Basin is one of the smaller basins associated with the Karoo basins of the Late Carboniferous–Middle Jurassic age interval. The preserved SBF basin is a topographically flat area with very few outcrops. It has a NE-SW orientation and is approximately 205 km long and 30 km wide. This study is based on borehole log data captured by the Council for Geoscience, which has been collected from various exploration companies throughout the history of the investigation of the SBF Basin area. The purpose of this study is to identify an evolutionary history of the basin by utilising methods of basin analysis and literature search, and to establish how the basin relates to other Karoo Supergroup basins in southern Africa. The postulated genetic model of a retroarc fore-bulge rift basin was compared to the inferred depositional environments. The geophysical interpretations and structural contour maps of the various strata indicate the presence of the major Zebedelia Fault, which is part of the Thabazimbi Murchison Lineament (TML) relay system. This fault runs along the northern boundary of the basin and has caused the strata of the SBF Basin to be down-faulted by 800 to 1000 metres. The isopachs of the identified Karoo successions do not indicate thickening towards this lineament, which suggests that the faulting along this lineament post-dates the Karoo sedimentation. The Thabazimbi Murchison Lineament played a significant role during the later stages of the SBF sedimentation. Once the depocentre became more centrally located in the depository, it began to migrate towards the TML. Although the major faulting was yet to occur, the weakness in the craton was apparent. During the breakup of Gondwana, the Zebedelia Fault shifted the strata down and allowed the extrusion of the Letaba Basalt, along with the multi-intrusion of dykes throughout the strata. The onset of the deposition of the Karoo Stratigraphy in the SBF was due to uplift resulting from the mid-carboniferous assembly of Pangea. During the Lower Karoo deposition, lithospheric subsidence was facilitated by crustal-scale faults, resulting in the deposition of the glacial Dwyka and Lower Ecca sediments. Flexural subsidence was occurring in the forebulge due to the relaxing of the initial compression of the Cape Fold Belt (CFB). The later Ecca succession was characterized by large subsidence with little accompanying brittle deformation. The lower Beaufort was a deltaic basin and was terminated towards the end of the Permian period, identified by a significant loss of fauna and flora. There was a ± 3km uplift, known as the Namaqua Uplift and erosion north of the fold belt. This marked the structural inversion during deposition of the Beaufort Group and Early Molteno Formation. These uplift events resulted in uplift in the foredeep which resulted in the compression of the forebulge during the deposition of the Molteno Formation. Once these events subsided, the forebulge relaxed and underwent subsidence and extension. Elliot Formation formed during this unloading of structural relief and relaxation of basinforming stresses. The upper Elliot and Clarens formations and Letaba Basalts exhibit the transition from sinistral strain of the late Karoo Basin to the dextral tectonics of the Gondwana breakup that terminated the basin deposition. The Karoo sediments in the SBF Basin clearly represent the broad spectrum of the same set of palaeoenvironments that are recognised in the Main Karoo Basin rocks. These reflect the progressive infilling of the Karoo Basins, the changing tectonic framework as well as the migration of Gondwana from polar to tropical latitudes. However, due to the development of the SBF basin on the forebulge, the compression of the CFB had the opposite effect, where it resulted in uplift of the fore-bulge and subsidence of the foredeep. This subsequently resulted in the SBF correlated Karoo sedimentary successions being markedly thinner than those of the Main Karoo Basin, and in some cases, certain strata are completely absent. An extensional basin formed by reactivation of older structures, such as the TML, as a result of displacement on the principle shear zones. This resulted in the preservation of the SBF strata in the basin today. This study is a baseline and preliminary investigation into the SBF Basin, and may act as a canvas to which more in-depth investigations may be added. Various questions have been identified that require further understanding and are listed under recommendations. Many of the questions put forth may be answered with a thorough Quality Assurance-Quality Control (QAQC) of the database.
Dissertation (MSc)--University of Pretoria, 2014.
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Geology
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Rafuza, Sipesihle. "Carbonate petrography and geochemistry of BIF of the Transvaal supergroup : evaluating the potential of iron carbonates as proxies for palaeoproterozoic ocean chemistry." Thesis, Rhodes University, 2015. http://hdl.handle.net/10962/d1018611.

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The subject of BIF genesis, particularly their environmental conditions and ocean chemistry at the time of deposition and their evolution through time, has been a subject of much contentiousness, generating a wealth of proposed genetic models and constant refinements thereof over the years. The prevailing paradigm within the various schools of thought, is the widespread and generally agreed upon depositional and diagenetic model(s) which advocate for BIF deposition under anoxic marine conditions. According to the prevailing models, the primary depositional environment would have involved a seawater column whereby soluble Fe²⁺ expelled by hydrothermal activity mixed with free O₂ from the shallow photic zone produced by eukaryotes, forming a high valence iron oxy-hydroxide precursor such as FeOOH or Fe(OH)₃. An alternative biological mechanism producing similar ferric precursors would have been in the form of photo-ferrotrophy, whereby oxidation of ferrous iron to the ferric form took place in the absence of biological O₂ production. Irrespective of the exact mode of primary iron precipitation (which remains contentious to date), the precipitated ferric oxy-hydroxide precursor would have reacted with co-precipitated organic matter, thus acting as a suitable electron acceptor for organic carbon remineralisation through Dissimilatory Iron Reduction (DIR), as also observed in many modern anoxic diagenetic environments. DIR-dominated diagenetic models imply a predominantly diagenetic influence in BIF mineralogy and genesis, and use as key evidence the low δ¹³C values relative to the seawater bicarbonate value of ~0 ‰, which is also thought to have been the dissolved bicarbonate isotope composition in the early Precambrian oceans. The carbon for diagenetic carbonate formation would thus have been sourced through a combination of two end-member sources: pore-fluid bicarbonate at ~0 ‰ and particulate organic carbon at circa -28 ‰, resulting in the intermediate δ¹³C values observed in BIFs today. This study targets 65 drillcore samples of the upper Kuruman and Griquatown BIF from the lower Transvaal Supergroup in the Hotazel area, Northern Cape, South Africa, and sets out to explore key aspects in BIF carbonate petrography and geochemistry that are pertinent to current debates surrounding their interpretation with regard to primary versus diagenetic processes. The focus here rests on applications of carbonate (mainly siderite and ankerite) petrography, mineral chemistry, bulk and mineral-specific carbon isotopes and speciation analyses, with a view to obtaining valuable new insights into BIF carbonates as potential records of ocean chemistry for their bulk carbonate-carbon isotope signature. Evaluation of the present results is done in light of pre-existing, widely accepted diagenetic models against a proposed water-column model for the origin of the carbonate species in BIF. The latter utilises a combination of geochemical attributes of the studied carbonates, including the conspicuous Mn enrichment and stratigraphic variability in Mn/Fe ratio of the Griquatown BIF recorded solely in the carbonate fraction of the rocks. Additionally, the carbon isotope signatures of the Griquatown BIF samples are brought into the discussion and provide insights into the potential causes and mechanisms that may have controlled these signatures in a diagenetic versus primary sedimentary environment. Ultimately, implications of the combined observations, findings and arguments presented in this thesis are presented and discussed with particular respect to the redox evolution and carbon cycle of the ocean system prior to the Great Oxidation Event (GOE). A crucial conclusion reached is that, by contrast to previously-proposed models, diagenesis cannot singularly be the major contributing factor in BIF genesis at least with respect to the carbonate fraction in BIF, as it does not readily explain the carbon isotope and mineral-chemical signatures of carbonates in the Griquatown and uppermost Kuruman BIFs. It is proposed instead that these signatures may well record water-column processes of carbon, manganese and iron cycling, and that carbonate formation in the water column and its subsequent transfer to the precursor BIF sediment constitutes a faithful record of such processes. Corollary to that interpretation is the suggestion that the evidently increasing Mn abundance in the carbonate fraction of the Griquatown BIF up-section would point to a chemically evolving depositional basin with time, from being mainly ferruginous as expressed by Mn-poor BIFs in the lower stratigraphic sections (i.e. Kuruman BF) to more manganiferous as recorded in the upper Griquatown BIF, culminating in the deposition of the abnormally enriched in Mn Hotazel BIF at the stratigraphic top of the Transvaal Supergroup. The Paleoproterozoic ocean must therefore have been characterised by long-term active cycling of organic carbon in the water column in the form of an ancient biological pump, albeit with Fe(III) and subsequently Mn(III,IV) oxy-hydroxides being the key electron acceptors within the water column. The highly reproducible stratigraphic isotope profiles for bulk δ¹³C from similar sections further afield over distances up to 20 km, further corroborate unabatedly that bulk carbonate carbon isotope signatures record water column carbon cycling processes rather than widely-proposed anaerobic diagenetic processes.

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Vongo, Mthuthuzeli Rubin. "A case study of the goals of the business communication course at Technikon Witwatersrand." Thesis, Rhodes University, 2006. http://hdl.handle.net/10962/d1003949.

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At Technikon Witwatersrand, Business Communication is offered as a service subject, which is compulsory for a variety of diplomas and the majority of students are obligated to do the course. Its broad intention is to assist students in developing their proficiency in English, enabling them to cope with studying at Technikon and preparing them for the workplace. Despite the fact that the course is designed to assist them, many students question why they have to do the course and whether it is simply a repetition of high school work. The study attempts to examine the implicit and explicit goals of Business Communication, to explore the process through which the goals have been developed and changed over the years (i.e. how the goals have been constructed), and to elicit and compare the perspectives of the different stakeholder groups as to the goals. Both a qualitative and a quantitative approach are used in the research design. Interviews with four fulltime lecturers were conducted and a self-designed questionnaire was administered to students. These were the main means of data collection. The data reveals that the goals of Business Communication are implied rather than explicit. Despite this, students and lecturers see the course as important. Recommendations are made to help the Department of Business Communication to reflect on their practice with particular emphasis given to material development and the application of OBE principles.

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Bowen, Teral Barbara. "The geochemical stratigraphy of the volcanic rocks of the Witwatersrand triad in the Klerksdorp area, Transvaal." Thesis, Rhodes University, 1985. http://hdl.handle.net/10962/d1004932.

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This study lias initiated with the aim of identifying the existence of any geochemical criteria which may be used to distinguish between the various volcanic formations within the Witwatersrand triad. The Witwatersrand triad comprises three sequences: the Dominion Group at the base, the Witwatersrand Supergroup in the middle, and the Ventersdorp Supergroup at the top. It is underlain by Archaean basement rocks, and covered by rocks of the Transvaal sequence. The Dominion Group consists of the sedimentary Rhenosterspruit quartzite Formation at the base, overlain by a bimodal component of the Syferfontein Porphyry succession of lavas. Basaltic lavas are the major component of the Rhenosterhoek Formation, while the overlying Formation consists primarily of dacitic porphyries. Intercalations of one lava type within the other are common, however, so each formation is not the exclusive domain of only one lava type. The Witwatersrand Supergroup, a predominantly argillaceous and arenaceous sequence, contains two narrow volcanic horizons, one of wbich, the Jeppestown Amygdaloid (now Crown Formation), consisting of tholeiitic andesites, occurs in the study area. The overlying Ventersdorp Supergroup has, at its base, the basaltic Klipriviersberg Group, of which four out of six formations are present in the study area, namely, the Alberton, Orkney, Loraine and Edenville Formations. This group is succeeded unconformably by the PIatberg Group, consisting of the sedimentary Kameel doorns Formation, followed by the (informal) Goedgenoeg, Makwassie Quartz Porphyry and Rietgat Formations. The Goedgenoeg and Rietgat Formations are basaltic, whil e the Mawassie rocks range from basaltic to dacitic, the majority being tholeiitic andesites and andesites . The Pniel sequence at the top of the Ventersdorp Supergroup consists of the sedimentary Bothaville Formation, and the Allarridge Formation, the lavas of which are basaltic with some andesitic tendencies. A well-defined geochemical stratigraphy was found to exist. From the eleven volcanic formations examined, nine distinct geochemical units emerged, as the Loraine and Edenville Formations were found to have the same geochemical characteristics, as did the Goedgenoeg and Rietgat Formations. Despite having undergone law-grade greenschist facies metamorphism, very clear variation patterns with height are displayed by the immobile elements Ti, P, Kb, Zr and Y, and the light rare earth elements La, Ce and Nd. In contrast, much scatter was observed in the variation patterns of Na, K, Mn, Ba and Rb. Three techniques were employed to effect discrimination between formations - orthosonal discrimination, interelement and ratio vs ratio plots, and discriminant analysis. Confidence limits placed on normal probability plots served to isolate outlier samples for further examination by the various discrimination techniques. A successful test of the efficacy of the discrimination techniques was afforded when fourteen samples from an unknown succession were positively identified as representative of the Klipriviersberg Group

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Bordy, Emese M. "Sedimentology of the Karoo Supergroup in the Tuli Basin (Limpompo River area, South Africa)." Thesis, Rhodes University, 2001. http://hdl.handle.net/10962/d1005612.

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The sedimentary rocks of the Karoo Supergroup in the Tuli Basin (South Africa) consist of various terrigenous clastic and chemical deposits (parabreccias, conglo-breccias, conglomerates, sandstones, fine-grained sediments, calcretes and silc~etes). Four stratigraphic units were identified: the Basal, Middle and· Upper Units, and the CI~rens Formation. The palaeo-environmental reconstructions of the four stratigraphic units are based on evidence provided by primary sedimentary structures, palaeo-flow measurements, clast size/shape analysis, petrographic studies, palaeontological findings, borehole data and stratigraphic relations. The facies associations of the Basal Unit are interpreted as colluvial fan and low sinuosity, braid~d river channel with coal-bearing overbank and thaw-lake deposits. The interpreted depositional environment implies a cold climate, non-glacial subarctic fluvio-Iacustrine system. The current indicators of the palaeo-river system suggest flow direction from ENE to WSW. The lithologies of the Basal Unit are very similar to the deposits of the fluvial interval in the Vryheid Formation (Ecca Group) of the main Karoo Basin. There is no indubitable evidence for glacial activity (e.g. striated pavements or clasts, varvites, etc.), therefore the presence of unequivocal Dwyka Group correlatives in the Tuli Basin remains uncertain. The sedimentary structures and palaeo-current analysis indicate that the beds of the Middle Unit were deposited by an ancient river system flowing in a north-northwesterly direction. A lack of good quality exposures did not allow the reconstruction of the fluvial style, but the available data indicate a high-energy, perhaps braided fluvial system. The lack of bio- and chronostr~~igraphic control hampers precise correlation and enables only the lithocorrelation of the Middle Unit with other braided river systems either in the Beaufort Group or in the Molteno Formation of the main Karoo Basin. The depositional environment of the Upper Unit is interpreted as a low-sinuosity, ephemeral stream system with calcretes and silcretes in the dinosaur-inhabited overbank area. During the deposition of the unit, the climate was semi-arid with sparse precipitation resulting -iFlhighmagnitude, low-frequency devastating flash floods. The sediments were built out from a distant northwesterly source to the southeast. The unambiguous correspondence between the Upper Unit and the Elliot Formation (main Karoo Basin) is provided by lithological similarities and prosauropod dinosaurs remains. The palaeo-geographic picture of the Clarens Fonnation indicates a westerly windsdominated erg environment with migrating transverse dune types. The ephemeral stream deposits, fossil wood and trace fossils are only present in the lower part of the Formation, indicating that the wet-desert conditions were progressively replaced by dry-desert conditions. Based on lithological and palaeontological evidence, the Formation correlates with the Clarens Formation in the main Karoo Basin. At this stage, it remains difficult to establish the exact cause of the regional palaeo-slope changes during the deposition of the Karoo Supergroup in the Tuli Basin. It is probable that foreland system tectonics, which affected the lower part of the Supergroup (Basal Unit and Middle Unit?), were replaced by incipient continental extension and rift related tectonic movements in the Middle and Upper Units, and Clarens Formation.

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Tatham, Gayle Kirsten. "The University of the Witwatersrand History Workshop and radical South African historical scholarship in the 1970's and 1980's." Master's thesis, University of Cape Town, 1992. http://hdl.handle.net/11427/22561.

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The thesis examines the History Workshop at the University of the University of the Witwatersrand in the context of radical South African historical scholarship. Not only is the History Workshop shown to mirror developments in radical scholarship but it is seen to guide and stimulate particular directions of research. The history of the Workshop is traced and its academic as well as popularising activities are examined. The Marxist social history approach, which was encouraged by the Workshop, is considered with reference to the social and political environment in which it emerged, and the international and local historiographical context. The issues, themes and concepts reflective of that approach are unpacked and some thought is given to their impact on Marxist categories of analysis. The History Workshop is seen to reflect and to have some influence on the direction pursued in labour and urban as well as rural history. In labour history, it pursued concerns of the social history of labour. Labour history was to take two different paths in the 1980's due partially to the influence of the Workshop group. Urban history grew rapidly as a field in the 1980's. The triennial Workshops reflected that development while the Workshop group particularly encouraged social history concerns within that field. The development of Marxist social history is seen in the change from an economistic approach in some of the papers presented at the first History Workshops to a broader social history emphasis in many of the later papers. The themes and issues arising out of urban Marxist social history are considered, as is their impact on the understanding of South Africa's urban history in general. The Workshop reflected and encouraged social history themes in rural history studies, which was another expanding field of research in the 1980's. These themes incorporated Africanist insight as well as an emphasis on oral history and local history. The Marxist social history studies, which were presented at the triennial Workshops, produced new insights into the rural history of South Africa which challenged earlier theories. The History Workshop with its materialist social history approach acted as a forum and as such, a catalyst for a radical scholarship in South Africa. The triennial workshops reflected what was happening in the terrain of Marxist social history. These Workshops, which attracted a large gathering of local, as well as foreign academics, legitimised that research and gave the Marxist social history scholars a certain standing within the local academic community. Although the study of South Africa's past may have similar directions in the late 1970's and 1980's without the presence of the Workshop, that presence gave a coherence and an added impetus to those routes of Marxist social history.

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Olivier, Wernich Corné. "The geology of the Witteberg group, Cape supergroup, with specific focus on the Perdepoort member as a potential silica source." Thesis, Nelson Mandela Metropolitan University, 2010. http://hdl.handle.net/10948/1386.

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Selected outcrops of the Upper Devonian to Lower Carboniferous, Witteberg Group, Cape Supergroup were mineralogically and structurally analyzed. The study area is located approximately 30km northwest of Kirkwood and 10km south of Darlington Dam, Eastern Cape, South Africa. Strata predominantly consist of arenaceous Witpoort Formation, which includes the Perdepoort, and Rooirand Members. The Perdepoort Member is a thinly bedded quartzite also known as the "white streak". The Rooirand Member quartzite is a highly iron stained red-brown quartzite. The dark-grey, pyritic rich shales of the Kweekvlei Formation overlie the Witpoort Formation in the southern half of the study site. These shales are highly deformed and display closely spaced thrust faults and close folds. The study area encapsulates a range of folding from tight to open folds. Faulting consists of low angle north verging thrust fault, south verging back thrusts, south and north dipping normal faults, and strike-slip faults. Closely spaced, fore-land verging thrusts faults predominate over hinterland verging back thrusts. Normal faulting post-dates thrust faulting and utilized weaknesses in axial planar cleavage and in certain instances existing thrust fault planes. Strike-slip faulting post-dates thrusting and has in places reactivated pre-existing thrust fault planes. Macro scale folding includes overturned synclines and large anticlines which have been eroded, exposing older strata. Fold axes plunge at low to moderate angles west-southwest. This correlates with tension gashes which indicate north westward directed forces. Eastward directed forces are confirmed by the presence of tension gashes and strike-slip movement. The local geology displays north westward directed compression followed by strike-slip movement. Normal faulting post-dates all other structures and is associated with the Mesozoic break-up of Gondwana. The Perdepoort Member was sampled along strike, at different outcrop latitudes. Seven samples were selected for scanning electron microscope analysis. Samples are composed almost entirely of quartz; accessories include, biotite, muscovite, sericite, baryte, and apatite. Epigenetic hematite is present along cracks within certain samples Epigenetic hematite occur along cracks with oxides and phosphates in the form of rutile, apatite and monazite present in a number of samples. When compared to other silica extraction operations the Perdepoort Member appears viable for explotation. However, for the solar cell industry the purity of this horizon is clearly far below that required for industy.

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Warke, Matthew. "Stratigraphic and geochemical framework of the Palaeoproterozoic rise in atmospheric oxygen, Transvaal Supergroup (South Africa)." Thesis, University of Manchester, 2017. https://www.research.manchester.ac.uk/portal/en/theses/stratigraphic-and-geochemical-framework-of-the-palaeoproterozoic-rise-in-atmospheric-oxygen-transvaal-supergroup-south-africa(b0aa0021-946c-4f01-bf4e-297611aa2ec1).html.

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The Transvaal Supergroup (South Africa) records evidence of trace oxygen production in late Neoarchaean strata, approximately 200 million years before the 'Great Oxidation Event' (GOE) which is recorded within the Palaeoproterozoic Duitschland Formation (Transvaal Supergroup) between ~2.42 and 2.32 Ga. It is hypothesized that there was a secular rise in oxygen concentrations between the late Neoarchaean and the GOE which may be recorded within the 'mid-Transvaal' Supergroup (Tongwane Formation, Duitschland Formation, Koegas Subgroup). This project has integrated field sedimentology, petrography and geochemistry to build new or revised depositional and diagenetic frameworks for each of these successions and has assessed palaeoredox conditions using carbon isotopes and rare earth element and yttrium (REY) patterns and anomalies. Despite a complex paragenetic history, including medium-grade contact metamorphism, the Tongwane Formation preserves primary (or near-primary), carbon isotope (delta13Ccarb = ~0 ± 2 ‰VPDB) and REY patterns that are consistent with Palaeoproterozoic seawater. No anomalously positive delta13Ccarb values or cerium (CeSN) anomalies are preserved, suggesting limited build-up of free O2. The lower Duitschland Formation preserves previously undocumented lithofacies variations and an angular mid-Duitschland unconformity (which is contemporaneous with the GOE). A new depositional model is proposed; facies assemblages and geometries are consistent with deposition of a wave-influenced Gilbert fan delta deposited in an isolated depocentre created by localised extensional fault subsidence. Lower Duitschland Formation limestones and dolomites show depleted delta13Ccarb and delta18Ocarb values and marine REY patterns which lack CeSN anomalies. Negative delta13Ccarb values suggest incorporation of 12C from organic matter during early diagenesis. There is no evidence of significant free oxygen production. The Koegas Subgroup is unconformably overlain by glacial strata of the Postmasburg Subgroup; the two successions are not intercalated and therefore not synchronous. Marine REY signals with positive Ce anomalies are recorded in delta13Ccarb depleted, stromatolitic dolomite exposed on the farms Taaibosfontein and Sandridge. Small magnitude positive anomalies are likely calculation artefacts, though anomalies >30 % may reflect redox stratification. Neoarchaean cuspate stromatolites of the Gamohaan Formation record trace element distributions - imaged using synchrotron-based XRF techniques - that map to primary microbial structures are not attributable to syndepositional or diagenetic mineralisation processes. Thus they may prove to be indicators of specific microorganisms and metabolic processes, e.g. photosynthetically relevant metals (e.g. Mn, Cu, Ni) mapped in biogenic structures may serve as a 'fingerprint' of cyanobacterial oxygenic photosynthesis. Overall, no evidence is seen for a secular rise in oxygen in the mid-Transvaal. However, depositional frameworks and diagenetic processes have been determined and the retention of marine signals established within the Tongwane, Duitschland and Koegas successions. Therefore the findings of this project constitute a robust framework for future palaeoredox studies of the mid-Transvaal Supergroup.

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11

Manche, Jacqueline Boitumelo. "Restructuring urban local government in South Africa : options for the central Witwatersrand metropolitan area." Thesis, Massachusetts Institute of Technology, 1994. http://hdl.handle.net/1721.1/68291.

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Goossens, Angelique Emily Maria. "A study of the structural geology of the Witteberg Group and lowermost Karoo Supergroup, Darlington Dam, Jansenville District, Eastern Cape." Thesis, University of Port Elizabeth, 2003. http://hdl.handle.net/10948/291.

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A number of outcrops of the Witteberg Group and lowermost Karoo Supergroup rocks were studied in the area south of the Darlington Dam, Jansenville District, with the aim of documenting structural characteristics of the area. All lithologies are folded with fold styles varying from gentle to near isoclinal (based on interlimb angle). Fold axes are either sub-horizontal or plunging at gentle to moderate angles whereas axial planes dip gently to vertically (predominantly steep to sub-vertical). Folds verge predominantly towards the north but where southward verging they are associated with faulting or strongly folded areas. Folds plunge gently to the east-southeast and west-northwest. The area consists of a large anticlinorium with both first and second order folds occurring. Eastwest striking faults occur in the study area and are classified as normal, reverse and thrust faults. A study of the joint sets shows that there are four dominant joint directions, namely 18o, 33o, 97o and 107o (in order from least to most important). An interpretation of the tectonic history is presented in which the relationships between faults and folds show that faults formed during and after folding. Folding, and reverse and thrust faulting, occurred during the compressional events that formed the Cape Fold Belt, whereas the normal faults formed during the relaxation of these compressional forces or during the break-up of Gondwana.

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Odendaal, Rehana Thembeka. "Wits imagined: an investigation into Wits University's public roles and responsibilities, 1922 - 1994." Master's thesis, Faculty of Humanities, 2020. http://hdl.handle.net/11427/32899.

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This thesis examines the public roles and responsibilities of the University of the Witwatersrand, Johannesburg in the period 1922-1994. It does this through a close investigation of four moments in the history of the University, namely the foundation of Wits (1910s and 1920s); early debates about the entry of Black staff and students (1930s and 1940s); the Academic Freedom protests (starting in the mid-1950s) and the formation of the Wits History Workshop (from 1977 to the early 1990s). In each of these moments, social roles and perceptions of public responsibility were actively asserted or challenged through engagements between internal-university constituencies and external communities. The thesis identifies three core roles for Wits University over this period: providing technical and professional training; generating and authenticating expert knowledge and shaping people's ideas of citizenship. The practical and conceptual understandings of these three roles, however, have shifted over time as the University's conceptualisation of the communities it serves has changed. These shifts have happened in conversation with different civic and state actors. The thesis has found that ideas of the public roles of Wits are informed by an institutional sense of self-referential authority accumulated through various moments and practices in the University's history. This self-referential authority depends on a selective recalling of particular events and the ability of multiple narratives about the University's identity to circulate simultaneously. This self-referential authority draws on Wits' origins as an institution of late-Imperial modernity and its legacy as a so-called ‘open' university. Understanding the practices and legacies that have created these narratives through an examination of the University's history, is particularly important in the present moment when the future public responsibilities of South African universities are being vigorously questions and debated.

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Baiyegunhi, Christopher. "Sedimentary, geochemical and geophysical study of the Ecca group, Karoo supergroup and its hydrocarbon potential in the Eastern Cape Province, South Africa." Thesis, University of Fort Hare, 2017. http://hdl.handle.net/10353/4881.

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The Ecca Group of Karoo Supergroup is a sedimentary rock sequence that deposited between the Late Carboniferous (Dwyka Group) and the Late Permian-Middle Triassic (Beaufort Group). The Ecca Group investigated in this study is situated in the Eastern Cape Province of South Africa and it comprises mainly of shales, mudstones, siltstones and sandstones. The Ecca Group sequence contains considerable carbon content and suitable thickness to make it an ideal target for shale gas exploration. Previous studies put more emphasis on the geology and stratigraphy of the Ecca Group, this study revised the stratigraphy, and put new insight on the petrography, depositional processes, sedimentary facies, provenance, paleoweathering, tectonic setting, subsidence rates and history, electrical resistivity, source rock characteristics and diagenesis of the potentially feasible sandstone and mudrock reservoir rocks of the Ecca Group. Based on the lithological features, sedimentary structures and facies characteristics, the stratigraphy of the Prince Albert, Whitehill, Collingham and Fort Brown Formations of the Ecca Group is now subdivided into two informal members each, i.e. Lower Member and Upper Member. Furthermore, the Ripon Formation is now subdivided into three informal members. Each member has been asigned a lithological name. The grain size parameters show that most of the Ecca Group sandstones are very fine to fine grained, poorly to moderately well sorted, mostly near-symmetrical and mesokurtic in grain-size distribution. The linear discriminant function analysis is dominantly indicative of turbidity current deposits under deep marine environment for Prince Albert, Whitehill and Collingham Formations, shallow marine environment for Ripon Formation, while the Fort Brown Formation is lacustrine-deltaic deposits. Modal composition analysis and petrography studies revealed that the detrital components of the sandstones are dominated by monocrystalline quartz, feldspar and lithic fragments. The sandstones are compositionally and texturally immature and can be classified as feldspathic wacke and lithic wacke. The provenance analysis revealed plutonic and metamorphic terrains as the main source rocks with minor debris derived from recycled sedimentary rocks. The detrital modal compositions of these sandstones are related to back arc to island and continental margin of tectonic setting. Based on the detailed sedimentological analyses of outcrop and borehole data, fourteen lithofacies were identified and seven facies associations (FAs) were recognised. The facies associations are: FA 1: Shale and mudstones intercalated with siltstones, FA 2: Carbonaceous shale, mudstone with subordinate chert and sandstone, FA 3: Mudstones rhythmite with thin bedded mudstone and lenticular siltstone, FA 4: Greyish medium bedded sandstone intercalated with laminated mudstone, FA 5: Dark-grey medium to thick bedded mudstone and siltstone, FA 6: Thin to medium bedded sandstone alternated with thin bedded carbonaceous mudstone, and FA 7: Varved mudstone rhythmite intercalated with siltstone and minor sandstone. Sedimentological characteristics of the identified facies associations indicate four deposition environments, namely, deep marine basin, turbidite, shallow marine and lacustrine environments, which constitute a gradually regression sequence as a result of sea-level dropping and shallowing of the basin during the developmental processes. Geochemical analysis of the Ecca mudrocks and sandstones revealed that the rocks are of quartzose sedimentary provenance, suggesting that they were derived from a cratonic interior or recycled orogen. The petrography and geochemistry of the sandstones indicated that the source areas are composed of plutonic and metamorphic rocks with a minor component from sedimentary rocks. The geochemical diagrams and indices of weathering suggested that the granitic source rocks underwent moderate to high degree of chemical weathering. The tectonic setting discrimination diagrams support passive continental margin setting of the provenance.

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Stott, Joan. "Preservation or exploitation? : a study of the development of the mining rights legislation on the Witwatersrand goldfields from 1886 to 2008." Thesis, Rhodes University, 2009. http://hdl.handle.net/10962/d1002723.

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Elinor Ostrom (2005: 238) assumes that in understanding the make up and behaviour of institutional systems governing natural resources: “Resource users are explicitly thought of as rational egoists who plunder local resources so as to maximise their own short-term benefits. Government officials are implicitly depicted, on the other hand, as seeking, the more general public interest, having the relevant information at hand and the capability of designing optimal policies.” This thesis examines the validity of this assumption through an historical analysis of the deep-level gold mining industry of the Witwatersrand, South Africa. The main focus of the assessment is on the institutions of ownership – that is, the development of mining rights and title legislation between 1886 and 2008. The study looks at the legislations’ transformation and implementation from the perspective of the gold mining industry – made up of the mining finance houses and the Chamber of Mines of South Africa – and that of the state. The transformation of the mining industry’s institutional framework was both a choice by government as well as that of the firms in the mining industry. The theoretical framework is constructed from four areas of economic thought. These include: the neoclassical and Keynesian schools of macroeconomic thought; industrial organisation and its relevance to the relationship between firms and the market; institutional and new institutional economics; and finally property rights. The determinants of policy design and the impact of such design on firms and industry is examined. The development, implementation and use of the aforementioned legislation is examined from two perspectives, namely, that of preserver or exploiter. Throughout the history of this prominent South African industry, the motivation for action from the industry or government has oscillated between the two extremes of preserver or exploiter over the time period examined. The conclusion is drawn on an overall and broad focus of actions – with a strong focus on the most recent developments in mining legislation – post-1992.

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Moodley, Adam. "The sedimentary petrology of carbonate nodules in the Elliot Formation, Karoo Supergroup, main Karoo Basin (South Africa)." Master's thesis, University of Cape Town, 2016. http://hdl.handle.net/11427/20345.

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In South Africa, fossils found in the upper part of the Elliot Formation (Stormberg Group, Karoo Supergroup) are often associated with genetically poorly-constrained carbonate nodules. The origin of carbonate nodules i.e., pedogenic versus diagenetic, is important as pedogenic carbonate nodules can be used as palaeoclimate indicators, while diagenetic nodules carry limited palaeoclimatic information on the depositional setting. This research aims to characterize the carbonate nodules of the Elliot Formation macroscopically, petrographically and geochemically and to establish a diagnostic set of criteria to enable the differentiation between pedogenic and diagenetic nodules and/or diagenetic overprint. The research techniques employed in this study range from a) macroscopic field observations of the stratigraphic relationships of the nodules to the sedimentary features of the host rocks; b) sedimentary petrography of the textural features in the nodules; and c) X-ray diffraction for the assessment of the clay composition trapped within the nodules as compared to host rocks. Macroscopic field observations have shown that carbonate nodules found in the UEF are strongly associated with host rocks that contain pedogenic features such as root traces, burrows, colour mottling, and desiccation cracks, and thus are suggestive of ancient soils. However, the microscopic analysis of the nodules reveal no evidence for biological activities but rather a range of abiotic features such as septarian cracks, circumgranular cracks, and micronodules which are more likely have resulted from physicochemical processes that may have occurred during diagenesis. Clay minerals identified by X-ray diffraction include illite, muscovite, and montmorillonite confirm the generation of the sediments under arid to semi-arid climatic conditions.

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Nyathi, Nonhlanhla. "Stratigraphy, sedimentary facies and diagenesis of the ECCA group, Karoo supergroup in the Eastern Cape, South Africa." Thesis, University of Fort Hare, 2014. http://hdl.handle.net/10353/d1019776.

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This is a MSc research project, and is aimed at the new insight on the stratigraphy, sedimentary facies, diagenesis and depositional environments of the Ecca Group, Karoo Supergroup in the Eastern Cape Province. Methodologies used in this research include field investigation, stratigraphic logging, thin-section microscope study, X-Ray Diffraction (XRD) and Scanning Electron Microscopy (SEM) analyses. The stratigraphy of the Ecca Group is divided into five formations, namely the Prince Albert Formation, Whitehill Formation, Collingham Formation, Rippon Formation and the Fort Brown Formation from bottom upward. Based on the field investigation and laboratory correlation, the Prince Albert, Whitehill, Collingham, and Fort Brown Formations can each be subdivided into two new members, i.e. lower member and upper member; whereas three new members have been proposed for the Rippon Formation, i.e. lower, middle and upper members. The Ecca Group sediments were accumulated in various depositional environments, from bottom of deep marine environment, passed through the middle of deltaic environment, and ended in a lacustrine environment. The Prince Albert Formation, Whitehill Formation and the Collingham Formation were all deposited in a deep marine basin, whilst the Rippon Formation was laid down in a deltaic environment. As the climate gradually became warmer and drier, the top Fort Brown Formation was lastly deposited in a lacustrine environment. The stratigraphic succession of the Ecca Group constitutes a perfect regression sequence, indicating that the marine water gradually retreated and the sea-level gradually dropped. The rocks in the Ecca Group are mainly terrigenous sandstone and mudstone with some coarse grain-sized siliciclastic rock of conglomerate. The sandstones are dominated by feldspathic graywackes with minor quartz-wackes, and there are no arenites in the Ecca Group. Whereas the mudstones are dominated by grayish mudrocks and black shales, purer claystone was found in the turbidite facies of the Collingham Formation, which probably has economic significance for the future since the reserve is quite large. Optical microscope, XRD and SEM analyses demonstrated that the minerals in the Ecca Group include detrital minerals of quartz, orthoclase, microcline, plagioclase, biotite, muscovite; and clay minerals (smectite, kaolinite, illite and sericite). These minerals constitute the rock framework grains and cements whereas; the authigenic minerals of calcite and hematite were formed during diagenesis. Accessory minerals such as rutile and zircon are the heavy minerals present in the strata, and occur only in a small amount. Based on the lithologies, sedimentary structures and sequence stacking patterns, ten sedimentary facies have been recognised, namely 1) Grayish laminated and thin bedded shale facies, 2) Grayish laminated shale and intercalated chert facies, 3) Grayish rhythmite facies (all the three facies above were deposited in deep marine water); 4) Flat and lenticular bedded graywacke facies, 5) Grayish alternating mudstone and sandstone facies, 6) Dark organic rich mudstone facies, 7) Fossil bearing mudstone facies, 8) Laminated and thin bedded black mudstone with lenticular siltstone facies, 9) Interbedded grayish sandstone and mudstone facies (above Facies 4-9 were deposited in deltaic environment and appeared in the Rippon Formation); and 10) Varved rhythmic mudstone facies, which occurs only in the Fort Brown Formation and represents lacustrine sediments. Four types of cements have been identified in the rocks of the Ecca Group, including quartz, smectite, calcite and feldspar cements. The first three cement types are the major cement types, whilst the feldspar cement is minor and occurs only locally. Recrystallisation in Ecca sediments includes quartz, feldspar, clay mineral recrystallisation and conversion from smectite and kaolinite to illite and then to sericite. Replacement involves calcite replacing quartz, feldspar and clay matrix; accompanied by albitization, i.e. albite replacing other feldspar minerals in a deep burial environment. Dissolution in the Ecca Group involved calcite and kaolinite dissolving and leaching, which created more pore-space and increased porosity. The sediments of the Ecca Group went through three stages of digenesis, namely the early stage, the late stage and the up lift stage which led the rocks being exposed on the Earth’s surface and being weathered. In each stage, some minerals became unstable, then replaced by a more stable mineral suitable for the new diagenetic environment. Precipitation of cements and formation of authigenic minerals mostly occurred in the early diagenetic stage, which led the soft sediments becoming a hard rock; whilst recrystallisation, replacement, and dissolution took place mostly in the later diageneti

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Fryer, Lindi. "Controls on the distribution of manganese in banded iron-formations (BIF) of the palaeoproterozoic transvaal supergroup, South Africa." Thesis, Rhodes University, 2016. http://hdl.handle.net/10962/2926.

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The 2.65 to 2.05 Ga Transvaal Supergroup comprises one of the best-preserved and largely continuous successions in the world of Banded Iron-Formation (BIF), a chemical sedimentary rock composed of fine (mm to cm scale) interbanded iron-rich and iron-poor bands, developed atop the Archaean Kaapvaal Craton of southern Africa. The Transvaal BIF sequence contains at its upper stratigraphic part, an intriguing interlayered BIF-Mn association, namely the Hotazel Formation in the Kalahari Manganese Field, which constitutes the largest land-based manganese deposit on record. The genesis of the Hotazel deposits, and their exact significance in terms of atmosphere-hydrosphere-biosphere evolution, remain as elusive as they are challenging. In this thesis, an attempt is made to illuminate the origin and diagenesis of the Hotazel Formation and its post-depositional hydrothermal modification, through a highresolution geochemical study of the narrowest of the three BIF-Mn sedimentary cycles present in the Hotazel stratigraphy. This approach is coupled with a preliminary geochemical study of the distribution of Mn in older BIF of the Transvaal Supergroup as well (Kuruman and Griquatown Formations), so as to test recent models that causally link all BIFs in the Transvaal Supergroup under a common and evolving palaeo-environment of deposition. The results indicate that the cyclic deposition of the Hotazel BIF and enveloped Mn-rich sediments would have taken place in a stratified basin with a well-developed chemocline in terms of the vertical distributions of Mn and Fe, much like recent anoxic stratified basins such as the Orca Basin in the Gulf of Mexico. The increased Mn abundances as Mn-bearing ferrous carbonates in the upper part of the Griquatown BIF predating the Hotazel strata, also seems to lend support to the notion that the two BIFs are temporally interlinked as part of a broader sedimentary continuum. Finally, the largely conservative behaviour of Mn and associated elements during hydrothermal alteration of the Hotazel rocks is re-assessed, and renewed emphasis is placed on the possibility that brine metasomatism may have been a key factor in Mn redistribution and residual enrichment.

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Van, Eeden Johan. "Basin analysis and sequence stratigraphy a review, with a short account of its applicability and utility for the exploration of auriferous placers in the Witwatersrand Basin." Thesis, Rhodes University, 1996. http://hdl.handle.net/10962/d1005546.

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The Witwatersrand basin is unique in terms of its mineral wealth. The gold in the Witwatersrand basin is mainly concentrated in the placers and two types of unconformities are associated with the placer formation. This paper attempts to quantitatively describe the origin and depositional process of placers within the context of basin analysis, geohistory and sequences stratigraphic framework. Several tectonic models have been proposed for the evolution of the Witwater~rand basin and it seems as if a cratonic foreland basin accounts for many of the observed features observed the Central Rand Group basin. The tectonic subsidence curve generated for the Witwatersrand Basin clearly implies foreland basin response which was superimposed an older, deep seated extensional basin. These compressive tectonics can be superimposed on extensional basins, where the shift from extensional to compressional tectonics lead to inversion processes. The critical issues about the Witwatersrand basin which were addresed in this review, is the validity of basin wide correlation of placer unconformuties and whether sequence stratigraphy is applicable to fluvial systems of the Witwatersrand sequence. It is believed that the Central Rand Group was deposited as alluvial - fan deltas by fluvially dominated, braidplain systems with minor marine interaction which had a considerable impact on the preservation of economically viable placers. Most important to the exploration geologist is the recognition of stacking patterns of the fluvial strata to determine change in the rate at which accommodation was created. Identifying sequence boundaries and other relevant surfaces important for identifying these stacking patterns of the sequences, depends entirely on the recognition of a hierarchy of stratal units including beds, bedsets, parasequences, parasequence sets and the surfaces bounding sequences. Placers are closely associated with the development of disconformities and therefore become important to recognise in fluvial strata. If these placers are to become economic, the duration of subaerial exposure of the unconformities that allowed the placers to become reworked and concentrated must be determined. In order to preserve the placer, a sudden marine transgression is necessary to allow for minimal shoreline reworking and to cap the placer to prevent it from being dispersed. The placers in the Witwatersrand basin occur in four major gold-bearing placer zones in the Central Rand Group. Accordingly they can be assigned to four supercycles, which are cyclical and therefore predictive. It is the predictive nature of these rocks and the ability of sequence stratigraphy to enhance this aspect, which is a pre-requisite for an effective exploration tool in the search for new ore bodies or their extension in the Witwatersrand basin.

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Sumner, Dawn Yvonne 1966. "Facies, paleogeography, and the carbonate precipitation on the archean (2520 Ma) Campbellrand-Malmani carbonate platform, Transvaal supergroup, South Africa." Thesis, Massachusetts Institute of Technology, 1995. http://hdl.handle.net/1721.1/57758.

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Mothoagae, Gaolatlhe. "A review of University of the Witwatersrand medical students' community-based health promotion service learning projects in South Africa." Master's thesis, University of Cape Town, 2013. http://hdl.handle.net/11427/9418.

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Includes bibliographical references.
The purpose of this study was to review past SL projects that have been implemented by GEMP 1 and 2 students, in order to inform the future planning and conduct of the SL programme in the faculty. A document review of all available Power Point presentations for projects implemented from 2006 - 2011 was undertaken employing content analysis. Of approximately 286 projects completed, 183 documents were available for review.

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Guy, Bradley Martin. "Pyrite in the Mesoarchean Witwatersrand Supergroup, South Africa." Thesis, 2012. http://hdl.handle.net/10210/6219.

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Ph.D.
Petrographic, chemical and multiple sulfur isotope analyses were conducted on pyrite from argillaceous, arenaceous and rudaceous sedimentary rocks from the Mesoarchean Witwatersrand Supergroup. Following detailed petrographic analyses, four paragenetic associations of pyrite were identified. These include: 1) Detrital pyrite (derived from an existing rock via weathering and/or erosion). 2) Syngenetic pyrite (formed at the same time as the surrounding sediment). 3) Diagenetic pyrite (formed in the sediment before lithification and metamorphism). 4) Epigenetic pyrite (formed during metamorphism and hydrothermal alteration). It was found that the distribution of the pyrite varies with respect to the stratigraphic profile of the Witwatersrand Supergroup and depositional facies within the Witwatersrand depository. In this regard, the four paragenetic associations of pyrite are either scarce or absent in marine-dominated depositional environments, which occur in the lower parts of the succession and in geographically distal parts of the depository. Conversely, the four paragenetic associations are well represented in fluvial-dominated depositional environments, which occur in the middle and upper parts of the succession and in geographically proximal parts of the depository. However, it is worth noting that diagenetic pyrite in the West Rand Group occurs as in situ segregations in carbonaceous shale, whereas syngenetic and diagenetic pyrite in the Central Rand Group occurs as reworked and rounded fragments in fluvial quartz-pebble conglomerates. The strong association between fluvial depositional environments and sedimentary pyrite (syngenetic and diagenetic pyrite) infers a continental source of the sulfur (sulfide weathering or volcanic activity), whereas the lack of pyrite in marine depositional environments is consistent with the model of a sulfate-poor Archean ocean. The connection between epigenetic pyrite and the fluvial-dominated depofacies is probably related to the elevated concentrations of precursor sulfides (i.e., remobilization of syngenetic and early diagenetic pyrite) and the presence of organic carbon (conversion of metal-rich early diagenetic pyrite into pyrrhotite and base metal sulfides). In support of the petrographic observations above, it was found that the trace element chemistry of each paragenetic association of pyrite yields a distinctive set of chemical compositions and interelement variations (Co, Ni and As contents). Regarding detrital pyrite, two chemical populations can be distinguished according to grain size: 1) small grains (tens of μm’s) with high levels of metal substitution (up to wt. %) and interelement covariation and iv 2) large grains (>100 μm) with low levels of metal substitution (≤200 ppm). These two populations are thought to represent pyrite derived from sedimentary and metamorphosed source areas, respectively (see below). The trace element chemistry of diagenetic pyrite varies relative to the Fe-content of the host rock. Diagenetic pyrite from Fe-rich host rocks, such as magnetic mudstone and banded iron formation (BIF), generally contain low Ni contents (<500 ppm), moderate As contents (<1500 ppm) and relatively high Co contents (up to a few wt. %). Elevated concentrations of As probably reflect desorption of As from clays and Fe-oxyhydroxides during diagenetic phase transformations, whereas anomalous concentrations of Co are tentatively linked to the reductive dissolution of Mn-oxyhydroxides.

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Els, Barend Gerhardus. "The auriferous Middelvlei reef depositional system, West Wits Line, Witwatersrand Supergroup." Thesis, 2014. http://hdl.handle.net/10210/9563.

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Blane, Craig Harry. "Composition and provenance of quartzites of the Mesoarchean Witwatersrand supergroup, South Africa." Thesis, 2013. http://hdl.handle.net/10210/8712.

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M.Sc.(Geology)
The Mesoarchean Witwatersrand Supergroup is a remarkably well preserved siliciclastic dominated cratonic platform succession located on the Kaapvaal Craton in South Africa. The vast gold resources which have been mined since 1886 make it relevant for study. The study aimed to identify significant provenance shifts throughout the depositional life of the basin which should be reflected in the in heavy mineral populations and the geochemical composition of the siliciclastic rocks. The study identified major changes in the source rock compositions through the basin lifespan and inferred major tectonic events during the life of the basin. It was found that the mechanical effects of sorting in different depositional environments tended to obscure provenance shifts, but with careful evaluation of the various factors in play significant provenance shifts could be identified. It was found that these provenance shifts corresponded closely with major unconformity sequence boundaries identified by Beukes (1995). These major provenance shifts are a record of a major tectonic event during the development of the basin. The Hospital Subgroup records a passive trailing margin, fed by a combination of felsic and ultra-mafic source rocks. Within the Hospital Hill Subgroup, there is a trend of increasing ultramafic components in the source area with increasing stratigraphic height. This trend is believed to reflect progressive unroofing of tonalite and greenstone belt complexes over the life of the Hospital Hill Subgroup. At the base of the Promise Formation a basin wide unconformity is present, which marks a shift from mature shallow marine and outer shelf sediments of the Hospital Hill Subgroup to immature fluvial quartzites for the Government and Jeppestown Subgroups (Beukes, 1995). In addition to the major change in depofacies that was recognised by Beukes (1995), this study found evidence for a shift in provenance to generally more fractionated source rocks, that were heterogeneous, but well mixed. The presence of lithoclasts indicates a possible metamorphic component was also present in the source area. This is consistent with a source area containing granitoid batholiths, and granite plutonism which is associated with early subduction tectonics and volcanic arc formation during the deposition of the Government and Jeppestown Subgroups (Wronkiewicz and Condie, 1987 and Poujol, et al., 2003, Kositcin and Krapez, 2004). Another important basin wide unconformity is present at the base of the Johannesburg Subgroup, and marks another major provenance change. These rocks are chemically more mature than the Government and Jeppestown Subgroups and represent a shift to an immature fluvial depositional setting related to basin closure (Beukes, 1995). A shift to moderate Th:Sc and La:Sc suggests a less fractionated mix of source rocks. The disappearance of the lithoclasts indicates that the metamorphic source rocks no longer supplied material to the basin. A small increase in the chromite to zircon ratio also suggests that some unfractionated source rocks were present. The narrow range in Th:Sc, La:Sc, Nb:Y ratios suggests that a homogeneous source area is present, but this is contradicted by the highly variable zircon ages measured by Kositcin and Krapez (2004), so the narrow spread might indicate that the rocks are very well mixed. Zircon populations measured by Kositcin and Krapez (2004) suggest that source terrain of the Johannesburg Subgroup probably consisted of a mixture of the granitoid batholiths from which the Government and Jeppestown Subgroups are a derived as well as some intermediate igneous material with ages of 3000-2870 ma. This would reflect incorporation of syntectonic granitoid plutons into the source areas, Kositcin and Krapez, (2004). The Turffontein Subgroup rocks are very coarse and chemically mature, but they display poor to moderate sorting and rounding. The rocks were deposited in a fluvial environment but marine quartzites are not uncommon. It is believed that these rocks were transported in a high energy environment, but the duration of transportation was short. This allows for effective winnowing but insufficient time for physically mature rocks with well-rounded grains to develop, explaining the mature chemical composition but immature physical composition. The source rocks of the Turffontein Subgroup were probably the same as the Johannesburg Subgroup with the higher energy mode of transportation responsible for the observed increase in Zr:Ti ratio. It would also explain the scarcity of feldspars and chlorite in the Turffontein Subgroup. Th:Sc and Nb:Y ratios suggest highly fractionated source rocks, but care must be taken because the mature nature and coarse grainsize of these rocks make trace element analyses unreliable. The zircon population indicates the presence of 3090-3060ma (Kositcin and Krapez, 2004) granite batholiths, as well as 3000-2870 Ma (Kositcin and Krapez, 2004) syntectonic granite plutons, as well as ancient granitoid gneiss (Kositcin and Krapez, 2004) in the source area. This study has provided new support for a foreland basin origin of the Witwatersrand Supergroup, proposed by Beukes (1995), Beukes and Nelson (1995) and Nhleko (2003), resulting from orogenic collision of the Witwatersrand and Kimberley blocks along the western margin of the Witwatersrand block. The Amalia, Kraaipan and Madibe greenstone belts and Colesberg Magnetic Anomaly are probably the only remaining remnants of this orogeny today.

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Genis, Jac H. "The sedimentology and depositional environment of the Beatrix Reef: Witwatersrand supergroup." Thesis, 1990. https://hdl.handle.net/10539/25042.

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A Dissertation Submitted to the Faculty of Science University of the Witwatersrand, Johannesburg for the Degree of Master of Science.
Beatrix Mine is located 35 km south of the city of Welkom in the Welkom Goldfield and as such forms the most southerly of the Witwatersrand-type gold mines. The Beatrix Reef overlies an angular unconformity at the base of the Turffontein Subgroup, Central Rand Group Significant, southerly truncation of over 600m of the Johannesburg Subgroup, and the lower formations of the Turffontein Subgroup, occur at this unconformity in the Beatrix area.. characteristics of the Beatrix Reef conglomerates such as the morphology, sorting and packing of clasts, and the arrangement. of the sediments in various sedimentary structures and facies/ sequences, suggest deposition within a braided fluvial environment on a coarse-grained braid-delta. Sedimentation occurred after the fluvial degradation of previously deposited units, and culminated in a marine/ lacustrine transgression. Low aggradation rates led to significant reworking and concentration of placer materials in a depositional model probably typical of ventral Rand Group placer formation. Heavy minerals (and gold) are concentrated in response to hydraulic conditions and show a close association with large and small scale sedimentary features. Transport directions deduced from the sedimentary structures suggest a north to south dispersal of sediment down the braid plain. Sedimentary structures in the finer rained units at the base of the Eldorado Formation are indicative of tidal influences and document the marine transgression as the culmination of the degradational events. The lithologys sedimentary structures and facies sequences of the coarser grained units of the Eldorado Formation well as the overall coarsening upward of these lithologies indicate sedimentation in a braided , fluvial system, on an alluvial fan prograding across the preyiously deposited units" Sedimentary ~tructures and lithologic variations confirm a continued north to south dispersal pattern. In the area south of the Sand over the period of fluvial degradation and transgression after the formation of the Beatrix: Reef was followed by more rapidly aggreding fluvial progradation due to a major change in base level in response to compressional tectonics and uplift along the Western Margin Structure. Only in post-Central Rand Group times did relaxation and extensional tectonics result in the outpourings of the Ventersdorp .supergroup lavas and the cessation of active Witwatersrand Supergroup sedimentation.
Andrew Chakane 2018

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26

Mkhatshwa, Sindile Francisca. "Assessment of the mineralogical variability of the A1, UE1A, and A5-reefs at Cooke Section, Rand Uranium, using MLA-based automated mineralogy." Thesis, 2012. http://hdl.handle.net/10210/6347.

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M.Sc.
This study focuses on the mineralogical variability of the A1, A5 and UE1A Elsburg reefs, obtained at Rand Uranium’s underground mining areas. A total of 133 reef samples, consisting of the Elsburg UE1A, A1 and A5-reefs have been obtained from Cooke 2 and 3 (two of the three Rand Uranium Mines) using the conventional chip sampling method. One of the challenges faced by Rand Uranium Gold Mines in the Cooke section area is the difficulty in differentiating between the various reef types by means of their macroscopic characteristics (colour, pebble types/sizes/shapes, sorting, matrix type, visible sulphide mineralization etc.). This difficulty led to this study which is aimed at utilizing mineral liberation analyzer (MLA)-based automated mineralogy to distinguish between the various reefs and to assess the mineralogical variation within the A1, A5 and UE1A-reefs. The mineralization in this area is hosted by the upper Central Rand Group of the Witwatersrand Supergroup. The main orebodies that are exploited at the mines occur within the Gemsbokfontein Member of the Elsburg Formation. These orebodies have been deformed into an east-west trending anticline at Cooke 3. The present study also attempts to prove or disprove the equivalence of the UE1A-reef on the western limb of the anticline to the A1 or A5-reefs on the eastern limb of the anticline on the basis of mineralogy. Representative splits of the samples were subjected to mineralogical abundance quantification as possible through quantitative MLA-based modal abundance protocols such as XMOD. A standard file on the various mineralogical phases encountered, was created on the 600F MLA and complemented by quantitative XRD (X-ray diffraction) data. Mineral abundances were quantified by MLA, based on integrated backscatter electron (BSE) images and energy dispersive spectrometry (EDS) analyses. Thirty one minerals have been detected using the MLA and they include phases such as quartz, pyrophyllite, chlorite, brannerite, gold, monazite and pyrite as well as minor unknown minerals. Only a few of the minerals are relatively more abundant within the reefs while the majority occurs in very low abundance. Albite, chlorite, muscovite, pyrite, pyrophyllite, quartz, uraninite and zircon are relatively more abundant than the rest of the minerals.

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Coetzee, Dirk Stephanus. "Syn-tectonic quartz vein formation in relationship to metamorphism, fluid inclusions and thrust tectonism on the northern margin of the Witwatersrand Basin." Thesis, 2014. http://hdl.handle.net/10210/10899.

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D.Phil. (Geology)
A specific geological event has been characterized with the aid of an integrated metamorphic and fluid inclusion study of data obtained from syn-tectonic vein-quartz associated with thrusting and bedding-parallel shear along the northern margin of the Witwatersrand Basin. The vein-quartz associated with this event occurs as boudin-shaped bodies with their long and intermediate axes orientated within the foliation-, bedding- or fault-planes. The length of the quartz lenses which are spatially confined to shear zones often exceeds the thickness of the shear zones. These phenomena and the fact that quartz-fibres are orientated parallel to and not at right angles to the foliation confirms the syn-tectonic nature of the quartz veins. Heterogeneous P-T condition is indicative of imbrication, i.e. crustal thickening which is also substantiated by the random growth of pyrophylite and kyanite in shear zone assemblages, indicating that metamorphism outlasted deformation. Metamorphic studies of aluminous schists and vein-quartz with pyrophylliteand pyrophyllite - kyanite selvages established the development of two critical mineral assemblages: 1 Kaolinite + 2 Quartz = 1 Pyrophyllite + 1 H20 ... (1) and at higher P-T conditions 1 Pyrophyllite = 1 Kyanite + 3 Quartz + 1 H20 ... (2). The schists and quartz vein assemblages are quartz-oversaturated in contrast to the study material of Wallmach and Meyer (1990) which is quartz-undersaturated. Peak metamorphic conditions, therefore, are closely constrained by the position of the reaction curve (2) in P-T space, as is also substantiated by the presence of coexisting kyanite and pyrophyllite which are closely associated with syn-tectonic vein-quartz at the Florida Lake, Monarch Shaft and Krugersdorp localities. The nature of and circumstances under which the equilibrium aSsemblage pyrophyllite + kyanite + quartz has formed support an univariant situation, i.e. this assemblage can only coexist along the pyrophyllite kyanite isograd. The mineral assemblages that equilibrated during peak metamorphism are still present in the rocks of the shear zones, and show only incipient rehydration. The quartz-oversaturated nature of the rocks in the shear zones and the fact that kyanite formation is ascribed to reaction (2), cannot explain the abundance of quartz veins. Accordingly it is concluded that there must have been an external source from which Si02 was imported into shear zone to give rise to the formation of the large quantities of vein-quartz.

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28

Maré, Leonie Pauline. "Geothermal history of the Karoo Basin in South Africa inferred from magnetic studies." Thesis, 2015. http://hdl.handle.net/10210/13879.

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Ph.D (Geology)
The Karoo succession has economic significance through the exploitation of extensive coal deposits and in recent years has seen significant international interest due to potentially large shale gas resources. The thermal history of sedimentary basins affects the genesis of hydrocarbon deposits and it is therefore essential to model and reconstruct the geothermal variation across the Karoo Basin before evaluation of the hydrocarbon resources can take place. The main scientific questions related to the thermal history of the Karoo Basin are whether the emplacement of large volumes of magma was preceded by a large-scale lowgrade thermal doming as proposed for continental rift settings. Alternatively, was the Karoo thermal event restricted to the contact aureole of intrusives, as well as the question whether the intrusion of dolerite resulted in large-scale CO2 or CH4 degassing from coalbeds and carbonaceous shales based on similarities to other large igneous provinces? Magnetic techniques provide an alternative to more traditional methods to study the geothermal history of sedimentary basins (such as illite crystallinity and vitrinite reflectance), which are often associated with significant uncertainty. Three experiments using existing magnetic and palaeomagnetic methods were conducted to determine the peak temperatures reached by Karoo sedimentary rocks before and after the Karoo magmatic event. These experiments include the classic palaeomagnetic baked contact tests (magnetostratigraphy), analyses of the variation of magnetic susceptibility during repeated progressive heating (alteration index method) as well the variation of relative concentrations of fine grained pyrrhotite and magnetite in sedimentary strata relative to their distance from an intrusive (pyrrhotite/magnetite geothermometer). Additionally various magnetic fabric analyses were performed including a study of the variation in anisotropy of magnetic susceptibility (AMS). Although these techniques were successful in delineating the extent of the contact aureoles, only the alternating index (A40) had the ability to give estimated peak temperatures. Results indicate a general elevation of palaeotemperatures of the organic-rich sedimentary rocks of the Ecca Group to temperatures where hydrocarbons are normally converted into gas. Importantly, it is clear from this study that the greatest thermal effects of the sill intrusions on the sedimentary strata are limited to the contact aureoles, suggesting that there is an, as yet unquantified, potential for hydrocarbon resources remaining between these intrusions. A general increase in the palaeotemperatures from southwest to northeast across the basin was observed. This is mainly due to differences in thermal conductivity of the various lithologies across the basin from tight low porosity marine shales in the south and southwest towards more lacustrine mudstone and porous sandstone in the northeast.

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Van, Loggerenberg Etienne. "Residensiële patroonvorming aan die Witwatersrand : 'n meerveranderlike analise." Thesis, 2014. http://hdl.handle.net/10210/10751.

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30

Killick, Andrew Martin. "Pseudotachylites of the West Rand Goldfield, Witwatersrand Basin, South Africa." Thesis, 2014. http://hdl.handle.net/10210/11482.

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D.Phil. (Geology)
This study examines the nature, distribution and origin of a distinctive chert-like fault rock in the West Rand Goldfield of the Witwatersrand Basin in South Africa. These fault rocks, termed pseudotachylites, are characterized by an aphanitic groundmass enclosing subangular to rounded clasts of the host rocks. No glass has been observed in the matrix but features such as spherulites, coronas and altered margins to the host rocks as well as geochemical evidence, suggest that the pseudotachylite formed as a result of melting of the host rocks due to the heat generated by friction on faults. The colour of the pseudotachylite is a function of its chemical composition and parentage. The pseudotachylite has abrupt contacts with the host rocks which comprise a lower Proterozoic to Archaean succession of rocks belonging to the predominantly sedimentary Transvaal Sequence, the predominantly volcanic Ventersdorp Supergroup and the predominantly . sedimentary Witwatersrand Supergroup. The orientation of many of the pseudotachylite fault veins parallels a pre-existing set of mylonitic faults. These pseudotachylite fault veins most commonly occur in sub parallel southward dipping pairs and are accompanied by injection veins. If treated on a statistical basis, the vergence concept can be extended to injection veins to give the approximate movement direction of the fault system. The pseudotachylite is thought to be genetically related to brittle or semi-brittle extensional faulting of post-Transvaal age.

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31

Israelstam, Veronica Beatriz. "Cultural awareness in the development of educators at Technikon Witwatersrand." Thesis, 2014. http://hdl.handle.net/10210/11267.

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M.Tech. (Education)
The Technikon Witwatersrand (TWR) has lived through the legislative and socio-political changes occasioned by post-Apartheid South Africa. The institution has changed in terms of its demographics from being largely monocultural to being multicultural. A multicultural teachingllearning environment requires educators to be sensitive to cultural diversity and adapt their teaching styles to the needs of the culturally diverse learners. A previous internal report, conducted with a 100 strong focus group, had found many ... educators lacking in professional and attitudinal competencies. The study attempts to assess whether lecturers of the TWR Faculty of Business Management deem themselves to be culturally sensitive, whether they perceive themselves to have cultural knowledge and competence and whether this translates into their praxis. The study further examines whether the lWR Academic Development Unit has the requisite policies in place for both the personal and professional development of the academic staff of the TWR, with particular reference to cultural sensitivity. Both a qualitative and a quantitative approach are used in the research design. An exploratory group interaction and a self-designed questionnaire administered to a sample of academics are the main means of data collection. The data gathered reveals that there does not seem to be an attitudinal problem- and that educators are trying hard to adapt to the multicultural teachingllearning environment without much institutional support. The educators claim to have adapted their language usage, teaching methodology and course material to the culturally diverse learner population, though the data on this aspect is inconclusive. The study deals largely with perceptions, which, by their nature are difficult to verify. Recommendations are made to improve academic success through personal and professional development of the academic staff with particular emphasis on cultural sensitivity training.

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32

Swart, Quentin Dax. "Carbonate rocks of the Paleoproterozoic Pretoria and Postmasburg Groups, Transvaal Supergroup." Thesis, 2012. http://hdl.handle.net/10210/6946.

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M.Sc.
Certain carbonate bearing formations in the Paleoproterozoic Pretoria Group and its Griqualand West equivalent exhibit remarkable geochemical and stable isotopic signatures. The 8'3Ccarb isotopic signatures from the Duitschland and Silverton Formations exhibit large positive excursions, which seemingly coincide with a significant increase in atmospheric oxygen between 2.4 and 2.0 Ga. The Duitschland Formation with its distinctive basal unconformity is composed primarily of limestone and dolomite units, interbedded with two compositionally different shale units and quartzite. Toward the base of the formation there is a distinct conglomeratic quartzite which forms a sequence boundary above which isotopic and geochemical signatures change dramatically. Normal marine isotopic signatures characterize the lower portion of the succession while above the sequence boundari, the carbonates are enriched in "C. This enrichment, however, appears to be the result of local processes occurring within a closed basin. Furthermore it is apparent that the Duitschland Formation (with its three distinct marker beds) is the equivalent of the Rooihoogte Formation and therefore constitutes the base of the Pretoria Group. The Mooidraai Dolomite Formation which outcrops only locally in the Northern Cape Province, is characterized by fenestral and microbially laminated dolomite. The geochemical properties are relatively homogeneous with increases in the FeO and MnO concentrations, resulting from post depositional diagenesis. The stable isotope signatures of these dolomites represent normal marine signatures. There is, however, a depletion in the 813C and 8180 signatures in the ankeritic and sideritic lithofacies, which suggests that this succession was deposited from a stratified water column with respect to the total dissolved CO2. The positive 6 13C excursion present in the carbonates of the Lucknow Formation in Griqualand West, traditionally grouped with the Olifantshoek Group can be correlated with carbonates near the top of the Silverton Formation in the Transvaal area. The latter also displays distinctly positive 6 43C values. One possibility is that if these successions were deposited in closed anoxic basins and that the isotopic anomalies are the result of local processes such as fermentive diagenesis and methanogenesis. However, the close association of the carbonates with shallow marine orthoquartzites suggests that these were deposited in an open marine system and that the positive 8 !3C values reflect a shift in the composition of the ocean water at the time of deposition of the carbonates at 2.2 Ga. Other carbonates present in the Pretoria Group, namely from the Vermont and Houtenbek Formations, display normal open marine 8' 3C values of close to zero. A systematic stratigraphic compilation of all 6 43C values available from the Transvaal Supergroup indicates that two clear-cut positive 5' 3C excursions are present. These excursions were apparently short-lived and well defined and did not occur over an extended period of time as suggested by earlier studies based on global compilations with large uncertainties in radiometric ages of deposits.

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33

Zhao, Baojin. "A mineralogical and geochemical study of alteration associated with the Ventersdorp Contact Reef in the Witwatersrand Basin, South Africa." Thesis, 1998. https://hdl.handle.net/10539/26387.

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A thesis submitted to the Faculty of Science, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the degree of Doctor of Philosophy,
The Ventersdorp Contact Reef(VCR) is a major gold-bearing reef in the Witwatersrand Basin. It occurs between the overlying Klipriviersberg Group lavas and the underlying Central Rand Group sediments, and was strongly altered by hydrothermal fluids circulating in the Witwatersrand Basin. A detailed study of the mineralogy, geochemistry of rocks and minerals, physicochemical conditions, stable isotopes and ages of hydrothermal alteration zones associated with the VCR were carried out at Western Deep Levels South Mine, South Africa. ( Abbreviation abstract)
Andrew Chakane 2019

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34

Van, der Merwe Roelof. "The nature of the western margin of the Witwatersrand Basin." Thesis, 2014. http://hdl.handle.net/10210/12284.

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D.Phil. (Geology)
The tectonic evolution of the "western margin" of the Witwatersrand Basin is examined and indications are that it has undergone a long and complex history. In order to examine the nature of Witwatersrand-age structures, structures in both pre- and post-Witwatersrand sequences are also examined. Rocks of the ±3074 Ma Dominion Group were subjected to a tectono-metamorphic event prior to the deposition of Witwatersrand strata on an angular unconformity. An oligomictic conglomerate is sporadically developed at the base of the Witwatersrand Supergroup. PreVentersdorp structures in Witwatersrand strata are developed in two distinct trends, north-south and northeast-southwest. The relationship between the two directions of folds and thrust faults are best explained within a regional, sinistral transpressive shear couple; the north-south faults are sinistral strike-slip faults and the northeast-southwest trending folds and thrust faults are secondary structures associated with the strikeslip faults. The implications of this model are that Witwatersrand sedimentation was probably controlled by lateral movements on north-south trending faults and not by thrust faults in a foreland system as suggested by the most recent models of Witwatersrand basin development. Post-Witwatersrand deformation is complex. Southeastward verging, pre-Ventersdorp, thrust faults were reactivated as normal faults during Platberg times and the resultant half-grabens were infilled by conglomerates of the Kameeldoorns Formation. Later deformational events include eastward verging post-Ventersdorp thrust faults and post-Transvaal normal and strike-slip faults. It can be demonstrated that the majority of this later fault movements took place along pre-existing fault planes and therefore tectonic inversion is a fundamental process in the evolution of the Witwatersrand Basin. Clearly therefore, the present distribution of Witwatersrand strata does not reflect the original basin geometry, it is the result of several periods of basin inversion and no basin margins can be defined.

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35

Moore, J. M., H. Tsikos, and S. Polteau. "Deconstructing the Transvaal Supergroup, South Africa: implications for Palaeoproterozoic palaeoclimate models." 2001. http://eprints.ru.ac.za/446/1/Deconstructing_the_Transvaal_Supergroup%2C_South_Africa_-_implications_for_Palaeoproterozoic.pdf.

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Current correlations between the Pretoria and Postmasburg Groups of the Transvaal Supergroup are shown to be invalid. The Postmasburg Group is also demonstrated to be broadly conformable with the underlying Ghaap Group and therefore considerably older (~2.4 Ga) than previously supposed. The new stratigraphy documents an extensive (100 Ma) and continuous cold-climate episode with a glacial maximum at the Makganyene Formation diamictite. Iron formations of the underlying Asbesheuwels and Koegas Subgroups and overlying Hotazel Formation have similar origins, related, respectively, to the onset and cessation of the glacial event. This interpretation of the Transvaal Supergroup stratigraphy has significant implications for various Palaeoproterozoic environmental models and for the timing of the development of an oxygenated atmosphere.

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36

Klemd, Reiner. "A mineralogical and mineralchemical investigation of Archaean granites bordering the Witwatersrand basin." Thesis, 2014. http://hdl.handle.net/10210/12711.

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37

Mgolombane, Pura. "Institutional needs of the transgender student community at the University of the Witwatersrand." Thesis, 2017. https://hdl.handle.net/10539/24811.

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A research report submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Arts in Diversity Studies, July 2017
Transgender students in higher education in South Africa are increasingly coming out. Though this coming out at huge to cost for them in terms of personal safety, alienation. potential harassment, bullying and discrimination, this group of students are insisting that campuses should be inclusive and safe for everyone irrespective of their gender, sexuality and/or sexual orientation. [Abbreviated Abstract. Open document to view full version]
XL2018

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38

Theron, Johan Jacobus. "Die evaluering van die voortegnikuskursus as oorbruggingskursus aan die Technikon Witwatersrand." Thesis, 2014. http://hdl.handle.net/10210/11181.

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39

Donsky, Isidore Jack. "A history of silicosis on the Witwatersrand Gold Mines, 1910-1946." Thesis, 2014. http://hdl.handle.net/10210/11131.

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D.Phil. (History)
Silicosis as an occupational disease, has plagued the gold mining industry since its inception in 1886. This thesis attempts to describe the impact that silicosis had on the labour force of that industry from 1910 to 1946 and how all three participants, i.e. the state, industry and mine- workers became involved in attempting to combat this vital and dangerous problem, which was draining the health of a large and important sector of white and black workers within the South African community. This study focuses on two main themes, namely the cause and prevention of silicosis, which involves the development and use of advanced technology applied to mining operations and the compensation awarded to silicotic beneficiaries and their dependents. The disease not only became a health problem, but rapidly erupted into a sensitively politicised and emotional issue, which forms an important part of this thesis, involving all three parties. Another complex issue revolves around the question of contributions towards compensation to silicotic miners and who was liable for payment. This central problem only emerged after 1910, but continued throughout the period under discussion until 1946. In the process it became a highly controversial matter on which the state, industry and labour held widely divergent viewpoints. Also analysed are the attitudes and policies of the state and the mines towards white and black silicotics, the social responsibilities extended to each labour group and the effect racial relationships then current in South Africa had on the health problem as a whole.

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40

Rorke, Anthony John. "A seismically oriented study of mining induced fracturing around deep level gold mine stope." Thesis, 2014. http://hdl.handle.net/10210/11149.

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41

Taylor, Claire Janet. "The interactive experience of disability at the University of the Witwatersrand, Johannesburg." Thesis, 1997. https://hdl.handle.net/10539/26790.

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42

Jacobs, (nee Laubscher) Wanda Otilia. "Primêre gesondheidsorg deur plaaslike owerheidsverpleegkundiges." Thesis, 2014. http://hdl.handle.net/10210/10101.

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M.Cur.
With the announcement of the devolution of primary health care services to the local authority by the Cabinet in 1991, the role fulfilment of the community health nurse becomes more complex and greater demands are continuously made on her. The question, to what extent will the Implementation of primary health care (with the critical elements as framework) make greater demands on her role and function, led to this study. An exploratory, descriptive study, within a contextual framework was carried out. The purpose of the research was to analyse the task of the nursing staff working at local government, to determine which critical elements In primary health care are seen as part of the tasks of the community health nurse and to give guidelines with regard to primary health care and community health nursing. Content analyses done of job descriptions Indicated that some of the critical elements of primary health care are not expected to be performed by the nursing staff. According to the information gained through the questionnaires, nurses do more than is expected of them as Indicated In their job descriptions. " According to the conclusions resulting from this study, most of the critical elements of primary health care is being performed by nurses as part of their duty. The most Important recommendations Include the training of those nurses who feel that they need refresher courses with regard to the examination of patients and the making of diagnoses. Nurses need to know about the changes and what Is expected of them In future as a result of these changes.

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43

Hooper, Helena Clytie. "Die psigo-sosiale funksionering van ekonomies bedrywige en nie-bedrywige bejaardes." Thesis, 2014. http://hdl.handle.net/10210/8957.

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M.A. (Psychology)
The main objective of this study was to determine the influence of career involvement on the psycho-social well-being of the aged. An attempt was made to establish whether there would be any significant differences in life satisfaction, depression and self-concept, between economically active and non-active elderly persons. The research design was of an ex post facto nature. The sample consisted of 128 subjects between the ages of 60 and 80 years and was drawn from a middle to upper socio-economic population in the Witwatersrand area. Fifty of the respondents were still employed full-time, 16 were employed part-time and 62 were retired. Persons who reported poor physical health were excluded from the study. The Life Satisfaction in the Elderly Scale of Salamon and Conte and the Affect Balance Scale of Bradburn were used as measures of life satisfaction; the Centre for Epidemiological StudiesDepression Scale was used to measure depression and Vrey's Selfconcept Scale was used to measure self-concept. One way and two way analysis of variance were used to test the hypotheses...

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44

Conway, Peter Joseph. "Priority assessment of transportation projects in the central Witwatersrand area of South Africa." Thesis, 1994. http://hdl.handle.net/10539/22945.

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A thesis submitted to the Faculty of Engineering, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Science
Existing priority assessment procedures are reviewed with a view to identifying a methodology which will be appropriate for use in the Central Witwatersrand Regional services Council area. It is concluded that a two stage methodology is most appropriate, adopting a.successive sub-setting technique and a detailed sufficiency rating technique respectively, The methodology is tested on the 1992/93 project list.
AC2017

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45

Taback, Rayna. "Indigenisation of social service delivery in the Pretoria-Witwatersrand-Vereeniging region." Thesis, 1995. https://hdl.handle.net/10539/26647.

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Dissertation submitted to the Faculty of Arts, University of the Witwatersrand, Johannesburg in fulfilment of the requirements for the degree of Master of Arts in Social Work.
This study aimed at analyzing the social service programmes of 30 randomly selected 'progressive organisations' in terms of: 1. the nature of services offered 2. their rationale for service delivery 3. the goals of service delivery 4. the values and principles underlying service delivery 5. the strategies and methods used for service delivery 6. the outcome of services as perceived by the progressive organisations. on the basis of the information gathered, it was intended that this study would contribute towards an evolving understanding of the indigenisation process ocourring in social service delivery in South Africa. A qualitative-descriptive research design was used. A total of 103 organisations which met the requirements of a 'progressive organisation' with a 'social service programme' Were identified in the PWV area. From this universe, a 26% sample of 27 organisations was randomly drawn. An administered schedule was utilised in order to gather data from the respondents. Data was prooessed according to the SAS (Statistical Analysis of the Social sciences) programme. It was found that a move towards indigenisation has begun to emerge. This model of welfare has been in direct contrast to the traditional formal welfare system in South Africa Which historically was based on the ideology of apartheid. The major conclusions arising out of this study were that the progressive social service organisations under study were contributing towards the development of authentic social service delivery by: Incorporating social services into their programmes in order to meet the unmet social welfare needs of people, These unmet needs arose as a direct result of an inadequate formal welfare system in South Africa. Playing a major role in fulfilling peoples' unmet soclial welfare needs by offering services which welte traditionally not offered by most welfare organisations in South Africa. Incorporating new methodologies in to their service delivery as part of their commitment to make their services accessible and accountable to consumers. Being acutely conscious of the duality of their political and service objectives and delliberately striving to promote both. This combination of political and service objectives was carried out by including social development principles into service delivery. A general theme encapsulates the recommendations of this study. This refers to incorporating the experiences of the progressive social service movement into: social policy making education and training of social workers and, into furthering the process of authentication and indigenisation of social welfare in South Africa. It is further recommended that the indigenisation experiences of other countries should be studied in order to provide 'useful insights in the planning of a more appropriate model of social welfare in South Africa.
Andrew Chakane 2019

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"Die interhospitaalvervoer van siek neonate." Thesis, 2015. http://hdl.handle.net/10210/13338.

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M.Cur.
With reference to the question whether the interhospital transport of ill neonates in South Africa and more specifically in the Transvaal is adequate, a study was done in which the quality of the interhospital transport of ill neonates on the Witwatersrand was investigated. Criteria for the interhospital transport of ill neonates were formulated according to a literature review and they were validated. The quality of interhospital transport of ill neonates on the Witwatersrand was researched according to the formulated criteria. The case study method was used and was applied to neonates who were transported to a selected private- and provincial hospital by private- and provincial ambulance services between May 1987 and June 1987. Through the results of the study the researcher came to the conclusion that the interhospital transport of ill neonates on the Witwatersrand is inadequate. Recommendations which may contribute to the improvement of the transport system were made.

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De, Wet Louis Petrus Daniël. "The occurrence and bioaccumulation of selected metals and radionuclides in aquatic and terrestrial ecosystems on the Witwatersrand." Thesis, 2012. http://hdl.handle.net/10210/6077.

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Ph.D.
The investigations reported here conducted during 1990-1994 had the following objectives: Selection of representative localities in impoundments and rivers in wetlands affected by radionuclide- and metal-containing effluents and seepage water from mines and metal-processing industries. To determine the occurrence and concentration of radionuclides and selected metals in mine- and industry-polluted waters and sediments in catchments of the Blesbokspruit, the Klip River and the Crocodile River systems. To establish radionuclide and metal concentrations in some semi-aquatic and aquatic weeds in these mine- and industry-polluted waters with observations on the ability of some plants to accumulate certain metals in their roots and/or shoots. To evaluate some benthic macro-invertebrate organisms as possible indicators of radionuclide and metal pollution in the affected streams. To determine the radionuclide and metal concentrations in selected vegetable crops irrigated with mine- and industry-polluted water. The localities where the investigation took place were mainly in wetland regions on the East and West Rand. Water of polluted streams traverse expansive wetlands containing floating, emergent and submerged aquatic vegetation. These plants play an important role in the recovery from pollution of the affected waters. Pollutants are also available to and accumulated by other aquatic organisms such as crabs, fish and birds. In addition, the same water is often used for the irrigation of vegetable crops, thereby creating potential pathways through which these pollutants may be consumed by humans. All the above objectives have largely been met in as such that potential sources of pollution were identified and pollutants detected in the abiotic (water and sediments) environment. These pollutants were also found in wetland biota as well as agricultural crops irrigated with contaminated water. Potential pathways for the transfer of these pollutants were identified and dose assessment modelling was conducted.

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Nicolas, Merrill Victoria Mary. "Tetrapod biodiversity through the Permo-Triassic Beaufort Group (Karoo Supergroup) of South Africa." Thesis, 2008. http://hdl.handle.net/10539/5391.

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A B S T R A C T The rocks of the Beaufort Group of South Africa record a remarkably complete depositional sequence incorporating a rich fossil tetrapod succession from the mid-Permian to mid-Triassic. This represents one of the best preserved ecological assemblages of pre-mammalian terrestrial tetrapods documenting the stem lineages of both mammals and dinosaurs. For more than a century large collections of fossils from the Beaufort Group have been built up at various museums in South Africa. With the co-operation of all the South African museums curating collections of Karoo fossils, a single standardised database has been compiled for the fossils collected from the Beaufort Group as well as a GIS system incorporating all the South African databases of fossil records. Major problems which had to be overcome related largely to the non-standardised nature of different databases, locality, and taxonomic information. Particularly problematic was entering ambiguous and vague locality information onto the GIS database, so that it would still be useful for qualitative evaluation. The created GIS database is a useful analytical tool, but requires streamlining to make it accessible to all users. Completion of the foundation phase of the GIS database has highlighted problems which need to be addressed in the future to make the database an effective tool for research purposes.

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Fourie, Pieter Hugo. "Provenance and Paleotectonic setting of the Devonian Bokkeveld Group, Cape Supergroup, South Africa." Thesis, 2012. http://hdl.handle.net/10210/4331.

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M.Sc.
The Lower Devonian Bokkeveld Group is the Middle unit of the tripartite Cape Supergroup, which outcrops along the western, southern and eastern coastline of South Africa. A well-established sedimentary and stratigraphic understanding of the Bokkeveld Group allowed for geochemical and geochronological investigation in order to gain insight into the provenance characteristics, as well as the paleotectonic environment of the provenance areas. In order to observe any changes within the Bokkeveld Basin, complete profiles for geochemical investigation were sampled in the western, southern and eastern parts of the basin, and compared. Major and trace element patterns suggest that the western part of the basin received detrital input from felsic, magmatically evolved, and possibly alkaline sources, and that the sediment was highly recycled before deposition. Furthermore, the geochemistry suggests that the western part of the basin experienced “passive margin” type sedimentation. The geochemistry of the southern basin, in contrast, suggests input from less evolved, non-alkaline sources, and predicts sedimentation under “active margin” conditions for the lower part of the group. The eastern basin is geochemically intermediate between the western and southern basins. Zircon populations for the three parts of the basin further suggest that sources of different ages fed the three parts of the basin. The zircon population of the western basin suggests that the Namaqua Natal Belt (Mesoproterozoic) and Neoproterozoic cover successions were the major source of detritus, with only minor input from Paleozoic sources. The eastern basin also appears to have sourced mainly Namaquan aged material as well as Neoproterozoic material, with no Paleozoic input. The southern basin has a remarkably different zircon population, with the majority of grains being Paleozoic in age, and only a few Neoproterozoic and Mesoproterozoic grains. Furthermore, many of the grains are younger than any known source-rocks on the Kalahari Craton, and thus allude to input from an extra-Kalahari source into the southern part of the basin. The youngest grain from the southern basin overlaps with the established depositional age of the Bokkeveld Group, suggesting some syn-depositional or briefly pre-depositional magmatic activity in the source area(s) of the southern basin, as predicted by the geochemistry. The complete lack of zircon ages older than the Namaqua Natal Belt (Mesoproterozoic), would suggest that the Archean to Paleoproterozoic inner part of the Kalahari Craton, the Kaapvaal Craton, was not sourced by the Bokkeveld Group. This is most likely due to the Namaqua Natal Belt having served as a large east-west trending morphological divide during Bokkeveld deposition, preventing transport of detritus from the craton interior. Remarkably, this would suggest that the Namaqua Natal Mountain Range must have survived erosion and persisted as a morphological boundary for ca. 600 Ma to serve as the major source of detritus for the Bokkeveld Group. Even an extensive, craton-fringing sedimentary cover-succession such as the Bokkeveld Group, may thus not provide a “detrital fingerprint” of the craton interior, and paleogeographical implications must be taken into consideration during provenance studies. Paleocurrent directions for the Bokkeveld Group indicate a west to east transport direction in the southern part of the basin, and as such, a western, extra-Kalahari source, most likely the Rio de La Plata Craton and surrounds, is expected to have been the source of both the young Paleozoic zircons, as well as undifferentiated material as revealed in the geochemistry.

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Katz, Elaine N. "The white death: silicosis (miner's phthisis) on the Witwatersrand gold mines 1886-1910." Thesis, 1990. https://hdl.handle.net/10539/26127.

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A THESIS SUBMITTED TO THE FACULTY OF ARTS, UNIVERSITY OF THE WITWATERSRAND, JOHANNESBURG, IN FULFILMENT OF THE REQUIREMENTS FOR THE DEGREE OF DOCTOR OF PHILOSOPHY.
In its chronic form silicosis had always been been taken for granted as one of the occupational hazards of mining. But both during and shortly after the Anglo-Boer War it manifested itself in a new accelerated form amongst former Witwatersrand rock drillers. Despite the appointment in the Transvaal of a commission of enquiry in 1902 and the promulgation of dust precaution measures, by 1912 the prevalence of and mortality from the disease amongst the Witwatersrand miners had not diminished. This finding suggests two of the purposes of the study: first, the reasons for the continued prevalence of the disease; and second, the extent of the mortality from silicosis amongst the miners. Because of the apparently low prevalence of and mortality from the disease amongst African mineworkers, the disease was ironically nick-named the "white death". Therefore another aim of the study is to examine the validity of the medical claim that the short contracts of African migrant workers safeguarded them from contracting accelerated si licosis. As the subject is complex, the study uses a thematic approach. Chapters two to nine deal with significant themes: first, the growing medical knowledge concerning silicosis, the mining and medical precautions against the disease and the age-old disregard for the occupational illness in its chronic form; second, the industrialists* need to reduce working costs, the development of mass-production technologies and the resort by management to "speeding up"; and third, the miners' needs for job and wage security, the encroachment of African competitors in semi-skilled and skilled spheres of mining and the introduction and the extension of the colour bar. Chapter nine deals with underground health conditions. Chapter ten explores the awareness of the new form of the disease, accelerated silicosis, and the establishment in 1902 of the first Transvaal commission on silicosis. Chapter eleven discusses the failure to implement remedies. Finally, chapter twelve explores the prevalence of and mortality from silicosis and the impact of the disease on the workforce of the mines. In chapters ten, eleven and twelve a synthesis is offered of the themes and findings of the previous chapters. The project is based almost entirely on contemporary primary and published sources. Apart from silicosis, a unifying theme throughout the discrete sections is the perceptions of miners of their vocation in general, and of this occupational disease in particular. The study requires periodization. As silicosis is a slow-developing disease the starting point of the investigation is 1886, when gold was discovered on the Rand. The study ends in 1910 because the establishment of Union in 1910 and the legal award of compensation in 1911 heralded a new era in the history of silicosis on the South African gold mines. The following are the conclusions. First, almost an entire generation of overseas miners, most of whom remained migrants and whose skills pioneered the South African gold mining industry, died from silicosis. Second, for reasons of self-interest, some of which they shared with one another, both the Transvaal state and the Randlords did virtually nothing to remedy the occurrence of the disease. Both parties were culpable for the neglect of the health of the industry's workforce: using only perfunctory dust safeguards, management intensified production through the deployment of both modern technology and labour intensive practices, peculiar to the Witwatersrand; and most of the state's interventionist initiatives were the result of pressure from the British House of Commons. Third, the fear and anger of miners at being the victims of a preventable occupational disease, provided the catalyst for their militancy during the period. Fourth, the industry's power was partly responsible for causing both the press and medical profession to be silent about the problem until 1910. Finally, the mineowners both seized and promoted the unsubstantiated medical orthodoxy, namely that the short contracts of African mineworkers protected them from accelerated silicosis, as an important rationale for perpetuating the migrant labour system
Andrew Chakane 2018

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Dissertations / Theses on the topic 'Witwatersrand Supergroup (South Africa)'

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