This thesis reports the results of a mineralogical and geochemical study of pans situated in the Northern Cape Province with special emphasis on the clay minerals. From east to west the depth and size of the pans increase and associated with this increased maturity the abundance of salt (halite and thenardite) and the quantity of green sediment are also enhanced. Chemically the sediments are dominated by SiO2 that also dilutes Fe2O3, K2O, Na2O, Al2O3 and MgO (when associated with dolomite) concentrations. Authigenic calcite, dolomite, analcime and loughlinite (Na-sepiolite) occur in some of the pans to the west and FTIR spectrometry indicates that all the pans host glauconite and/or celadonite. However, smectite, illite/smectite interstratification, kaolinite and/or chlorite and loughlinite only occur in some pans. The glauconite and/or celadonite does not occur as discrete mineral grains, but forms part of the fine-grained matrix common to all of the pans and no evidence of any precursor minerals were observed. The pan environment appears to present a closed, saline setting that is conducive for the direct precipitation of a mica with a chemical composition between that of glauconite and celadonite. The influence of the water-table on the formation of the glauconite and/or celadonite appears to be significant, as the highest abundance of salt is invariably associated with the position in the profile where the sediment appears to reach its most intense green colour. In the case of Koi Pan, the celadonite component of the solid solution seems to increase as the green colour intensifies. Loughlinite in Koi Pan and Brak Pan sediments also appear to be authigenic and it is suggested that it forms after precipitation of low Mg calcite that leads to Mg enrichment of the system and consequent sepiolite formation associated with minor dolomite. Thermoluminescence ages obtained from the Koi Pan sediment range between 37ka and 48ka before present at a depth of ~120cm below the surface, while for Brak Pan, at roughly the same depth, an age of between 110ka and older than 150ka before present was obtained. This may suggest different sedimentation rates in the pans or much younger ages and thus faster formation of glauconite and/or celadonite in Koi Pan since it is suggested that the mineral is authigenic. / Thesis (M.Sc.)-University of KwaZulu-Natal, Westville, 2010.

<p>This thesis follows and builds upon a previous study at the rock engraving site of Driekopseiland (Morris 2002). The earlier findings are here contrasted with another site in the area, namely Wildebeest Kuil, as a means to highlight the variability which is a feature of the rock art of the Northern Cape as a whole. The main thrust of the thesis, which refers to a number of other rock art sites in the region, is to model the implications of this variability relative to social context and history in the precolonial past. Significant empirical obstacles, particularly the difficulties associated with dating rock art, render some aspects of the enterprise intractable for the time being. But opportunities are pursued to advance and evaluate ideas as to the social mechanisms and processes which might be implicated in the making and re-making of images on rock and in the generation of the diversity that is manifest in the rock art as it is found today. Whereas other approaches have tended to explain difference relative to social entities such as &lsquo / cultures&rsquo / or &lsquo / ethnic groups&rsquo / , this thesis offers, as a point of departure, a critique of received concepts, reconsidering some of the fundamental metaphors and assessing the elaboration of analogies that have been used in the past. It proposes that better theoretical footholds might be those that explain variability relative to process and movement. It invokes Tim Ingold&rsquo / s concept of a meshwork of dynamic relationships of people immersed in the world, of &lsquo / entanglements&rsquo / that refer to multiple mechanisms that might explain how rock art has changed in place and time. The pertinence of these ideas is shown with reference to specific instances in the Northern Cape.As a parallel weave in this study, there is a concern over the social role of archaeology, with discussion on the burgeoning salience of rock art beyond the academy, in the heritage and tourism sectors and amongst descendants of the Khoean. The thesis gives consideration to the role of museums and research in terms of &ldquo / heritage in practice,&rdquo / and seeks to develop a discourse in which, following Alexander, &ldquo / everything can be perceived as changing and changeable&rdquo / &ndash / an underlying theme throughout the study. The thesis does not bring empirical closure to the topic but suggests a programme for future engagement, having opened up and shown the relevance of wider theoretical insights for addressing the variability in the rock art of the Northern Cape.</p>

<p>This thesis follows and builds upon a previous study at the rock engraving site of Driekopseiland (Morris 2002). The earlier findings are here contrasted with another site in the area, namely Wildebeest Kuil, as a means to highlight the variability which is a feature of the rock art of the Northern Cape as a whole. The main thrust of the thesis, which refers to a number of other rock art sites in the region, is to model the implications of this variability relative to social context and history in the precolonial past. Significant empirical obstacles, particularly the difficulties associated with dating rock art, render some aspects of the enterprise intractable for the time being. But opportunities are pursued to advance and evaluate ideas as to the social mechanisms and processes which might be implicated in the making and re-making of images on rock and in the generation of the diversity that is manifest in the rock art as it is found today. Whereas other approaches have tended to explain difference relative to social entities such as &lsquo / cultures&rsquo / or &lsquo / ethnic groups&rsquo / , this thesis offers, as a point of departure, a critique of received concepts, reconsidering some of the fundamental metaphors and assessing the elaboration of analogies that have been used in the past. It proposes that better theoretical footholds might be those that explain variability relative to process and movement. It invokes Tim Ingold&rsquo / s concept of a meshwork of dynamic relationships of people immersed in the world, of &lsquo / entanglements&rsquo / that refer to multiple mechanisms that might explain how rock art has changed in place and time. The pertinence of these ideas is shown with reference to specific instances in the Northern Cape.As a parallel weave in this study, there is a concern over the social role of archaeology, with discussion on the burgeoning salience of rock art beyond the academy, in the heritage and tourism sectors and amongst descendants of the Khoean. The thesis gives consideration to the role of museums and research in terms of &ldquo / heritage in practice,&rdquo / and seeks to develop a discourse in which, following Alexander, &ldquo / everything can be perceived as changing and changeable&rdquo / &ndash / an underlying theme throughout the study. The thesis does not bring empirical closure to the topic but suggests a programme for future engagement, having opened up and shown the relevance of wider theoretical insights for addressing the variability in the rock art of the Northern Cape.</p>

M.Sc. (Geology) / Please refer to full text to view abstract

Philosophiae Doctor - PhD / This thesis follows and builds upon a previous study at the rock engraving site of Driekopseiland (Morris 2002). The earlier findings are here contrasted with another site in the area, namely Wildebeest Kuil, as a means to highlight the variability which is a feature of the rock art of the Northern Cape as a whole. The main thrust of the thesis, which refers to a number of other rock art sites in the region, is to model the implications of this variability relative to social context and history in the precolonial past. Significant empirical obstacles, particularly the difficulties associated with dating rock art, render some aspects of the enterprise intractable for the time being. But opportunities are pursued to advance and evaluate ideas as to the social mechanisms and processes which might be implicated in the making and re-making of images on rock and in the generation of the diversity that is manifest in the rock art as it is found today. Whereas other approaches have tended to explain difference relative to social entities such as ‘cultures’ or ‘ethnic groups’, this thesis offers, as a point of departure, a critique of received concepts, reconsidering some of the fundamental metaphors and assessing the elaboration of analogies that have been used in the past. It proposes that better theoretical footholds might be those that explain variability relative to process and movement. It invokes Tim Ingold’s concept of a meshwork of dynamic relationships of people immersed in the world, of ‘entanglements’ that refer to multiple mechanisms that might explain how rock art has changed in place and time. The pertinence of these ideas is shown with reference to specific instances in the Northern Cape.As a parallel weave in this study, there is a concern over the social role of archaeology, with discussion on the burgeoning salience of rock art beyond the academy, in the heritage and tourism sectors and amongst descendants of the Khoean. The thesis gives consideration to the role of museums and research in terms of “heritage in practice,” and seeks to develop a discourse in which, following Alexander, “everything can be perceived as changing and changeable” – an underlying theme throughout the study. The thesis does not bring empirical closure to the topic but suggests a programme for future engagement, having opened up and shown the relevance of wider theoretical insights for addressing the variability in the rock art of the Northern Cape

The Hartbees River Thrust Belt (HRTS) is a 40-60 km wide, southwest-vergent zone of complex structure, lithostratigraphy and high-grade metamorphism in the northeastern part of the mid-Proterozoic Namaqua Tectonic Province. The HRTS comprises the boundary zone separating the Bushmanland and Gordonia Subprovinces of the Namaqua Province. A knowledge of the movement histories of major ductile shear zones within the HRTS is fundamental to understanding the tectonic development of the belt, and Namaqua tectogenesis as a whole. In spite of this, no detailed microstructural kinematic studies have been attempted and the movement histories and age relationships of these shear zones have not been described in detail. This thesis represents a detailed microstructural kinematic study of a representative suite of orientated samples of mylonitic rocks, collected from five ductile shear zones within the HRTS. These shear zones include the Neusspruit Lineament, the Kakamas shear zone (KSZ), the Hugosput shear system (HSS), the Rozynenbosch-Ganzenmond shear zone (RGSZ) and the Graafwater shear system (GSS). Accepted modern methods of microstructural kinematic analysis were applied to samples of mylonite from these shear zones, in order to determine the precise orientation of the kinematic vectors, and the sense and relative ages of movements on each of the shear zones. Shear sense criteria, including composite SoC planar fabrics and shear band foliations, asymmetrical porphyroclast systems, mica-fish, oblique grain-shape and subgrain fabrics, asymmetrical microfolds, and the displacement of fractured rigid grains, together with a well-developed mylonite elongation lineation, conclusively indicate that SSW-directed thrusting occurred along the HSS, RGSZ, GSS and possibly along the Neusspruit Lineament, while normal, top-to-NE movements occurred on the Neusspruit Lineament, KSZ and HSS. Rare transposition criteria, and textural and paragenetic contrasts between syn-kinematic fabrics, strongly suggest that the phase of normal, top-to-NE movement seen in the northeastern HRTS shear zones is younger than the more widespread top-to-SW thrusting event. On the basis of mesoscopic structural criteria, SSW-directed thrusting is correlated with the D₂ deformation event in the HRTS. The mylonite zones have been refolded by ENE-SSW trending F₃ crossfolds, whose demonstrated coaxial relationship to the mylonite elongation lineation precluded reorientation of primary kinematic vectors. In the southwestern HRTS, primary thrust vectors have been reoriented by right-lateral, strike-slip shearing adjacent to the Pofadder Lineament during D₄. Simple shear dispersion of mylonite lineations related to normal movement, suggests that they too have been modified by D₄ shearing, and this constrains the timing of extensional movements to post-D₂ and pre- or syn-D₄. Syn-kinematic mineral assemblages, rheological criteria and the annealing states of the mylonites, provide insight into the thermotectonic evolution of the shear zones. A model is proposed in which the movement histories of shear zones within the HRTS are explained in terms of a typical orogenic cycle, involving crustal thickening by thrusting during a compressional orogenic phase, followed by collapse of the thickened crust during an extensional taphrogenic phase.

Banded iron-formations (BIFs) are chemically precipitated sedimentary rocks in which Fe-rich bands or laminae alternate with Fe-poor ones. They formed within a specific time-span of the geological record. Their occurrence is restricted between 2.3 and 1.9 Ga, and characterises virtually all the major Precambrian-aged sedimentary basins of the world. The Precambrian Transvaal Basin in Griqualand West, South Africa, is noted for its well-developed BIF units. The Kuruman and Griquatown BIFs comprising the Asbesheuwels Subgroup (up to 1000m thick) are the best known and thickest of these. As far as metallogenesis is concerned, the Kuruman BIF is of major importance, for it carries the world's largest crocidolite (blue asbestos) deposits. The uppermost, youngest member of iron-formation deposition in the Griqualand West Sequence is represented by the Voëlwater BIF. The direct association between the latter and the giant Mn-deposits of the Kalahari Field, renders the Voëlwater association unusual, if not unique, in the geological record. The Voëlwater BIF represents a typical example of the so-called "Superior-type", and in the area of study it has undergone late-diagennetic to low-grade metamorphic processes. This is evident from the mineralogical composition and textural signature of the various BIF lithologies. Specifically, the minerals that make up the Voëlwater BIF are mainly chert(quartz), Fe-oxides (magnetite and hematite), Fe-silicates (greenalite, stilpnomelane, minnesotaite, riebeckite, Fe-mica), Fe-carbonates (members of the dolomite-ankerite series and siderite), calcite and pyrite. Soft-sediment deformation structures and shear-stress indicators are abundant in carbonate-rich and granular, silicate-rich BIF lithologies respectively. The bulk chemical composition of the study rocks is relatively simple and is characterised by the abundance of essentially three elements, namely Si, Fe, and Ca, which make up more than 90% of the total chemical composition of the Voëlwater BIFs. The detrital component of the study rocks is negligible. Mn-enrichments characterise all the transitional lithologies towards the interbedded Mn-orebodies, as well as the well-developed, hematitic BIF-unit between the Ongeluk lavas and the lower Mn-horizon. In terms of trace element composition, no significant enrichments or depletions, were encountered, except for some unusually high values of Sr and Ba and Co in carbonate-rich and Mn-rich lithologies respectively. Geochemical comparisons on the basis of major, trace and light rare-earth element composition verified the similarity between the Voëlwater BIF and other major Superior-type BIFs of the world (e.g. Kuruman, Griquatown, Sokoman, Biwabik, Gunflint, Mara-Mamba, Brockman, etc.). The processes that led to the formation of the Voëlwater BIFs may have been very similar to the ones described in various genetic models proposed in recent years. They would have involved a combination of: i. hydrothermal processes related to mid-ocean ridge (MOR) or hot-spot activity that acted as major iron suppliers; ii. storm-mixing in stratified oceans (bottom, anoxic, Fe⁺² reservoir-thermo- pycnocline zone-upper, mixed, SiO₂-saturated layer), largely dictated by seasonal changes and contemporaneous volcanism; iii. periodic, convection-driven upwelling mechanisms acting as major Fe-precipitators; and, iv. organic carbon productivity that was responsible for the anoxic diagenesis of the initial sediment. However, the origin of Fe and Mn for the genesis of the Voëlwater sediments was difficult to explain with typical convection-cell models in active mid-ocean ridges, in contrast to previous hypotheses. Instead, large-scale endogenous processes in the form of magma convection, underplating, differentiation and associated degassing, may have played a critical role in the supply of metals for the formation of large amounts of BIFs in the Precambrian. The present study of the Voëlwater BIF also bears strong implications regarding the metallogenesis of Mn in the Precambrian. The common association of Mn with carbonate-bearing sediments, the transitional character of the Voëlwater BIF towards carbonate lithologies (Mooidraai dolomites) and the critical timing of the deposition of the former in terms of the Precambrian atmospheric-lithospheric- hydrospheric evolution, may be important indicators for the exploration of large Mn-deposits in Precambrian sedimentary basins of the world.

The Makganyene Formation forms the base of the Postmasburg Group in the Transvaal Supergroup in the Griqualand West Basin. It consists of diamictites, sandstones, banded iron-formations (BIFs), shales, siltstones and carbonates. It is generally accepted that the Makganyene Formation rests on an erosive regional unconformity throughout the Northern Cape Province. However this study demonstrates that this stratigraphic relationship is not universal, and conformable contacts have been observed. One of the principal aims of this study is to identify the nature of the Makganyene basal contact throughout the Griqualand West Basin. Intensive fieldwork was carried out from Prieska in the south, to Danielskuil in the north. In the Sishen and Hotazel areas, only borehole material was available to assess the stratigraphy. The Griquatown Fault Zone delimits the boundary between the deep basin and platform facies. The Koegas Subgroup is only present south of the Griquatown Fault Zone, where it pinches out. However, the transition Griquatown BIFs-Koegas Subgroup occurs in lacustrine deposits on the Ghaap platform (Beukes, 1983). The Griquatown Fault Zone represents the edge of the basin, which corresponds to a hinge rather than a fault zone. The Makganyene Formation rests with a conformable contact on the Koegas Subgroup south of the Griquatown Hinge Zone, and north of it the Makganyene Formation lies unconformably on the Asbestos Hills Subgroup. The Makganyene Formation displays lateral facies changes that reflect the paleogeography of the Griqualand West Basin, and the development of ice sheets/shelves. The Ghaap platform is characterised by coarse immature sand interbedded with the diamictites. The clasts in this area contain local Asbestos Hills material and no dropstones are present. Such settings are typical of sediments that are being deposited below a grounded ice mass. At the Griquatown Hinge Zone, the sandstone lenses are smaller, and the clasts consist of chert, of which a great number are striated and faceted. In the Matsap area, the presence of dropstones is strong evidence for the presence of a floating ice shelf that released its material by basal melting. Further south, the Makganyene Formation contains stromatolitic bioherms that only form if clastic contamination is minimal and therefore the ice that transported the detritus to the basin did not extend far into open sea conditions. The base of the Hotazel Formation also contains diamictite levels. Dropstones have been identified, implying a glacial origin. The Hotazel diamictites are interbedded with hyaloclastites and BIFs. The Makganyene glacial event, therefore, was not restricted to the Makganyene Formation, but also included the Ongeluk Formation, through to the base of the Hotazel Formation. Petrographic studies of the Makganyene Formation and the base of the Hotazel Formation reveal mineral assemblages that are diagnostic of early to late diagenetic crystallisation and of low-grade metamorphism not exceeding the very low green-schist facies. The facies identified display the same sense of basin deepening, from shallow high-energy Hotazel area on the Ghaap platform, to the deep basin in the Matsap area. Whole-rock geochemical analyses reveal that the elemental composition of the Makganyene Formation is very similar to that of the Asbestos Hills BIFs, which were the most important source of clastic detritus for the Makganyene Formation. However, minor amounts of carbonates of the Campbellrand Subgroup, as well as a felsic crustal input from the Archean granitoid basement, made contributions. On the Ghaap platform, the Makganyene diamictite is enriched in iron, calcium, and magnesium, while in the deeper parts of the basin the diamictites are enriched in detrital elements, such as titanium and aluminium, which occur in the fine clay component. The Hotazel diamictite displays a distinct mafic volcanic input, related to the extrusion of the Ongeluk basaltic andesites, which was incorporated in the glacial sediments. Sequence stratigraphy is based on the recognition of contacts separating the different systems tracts that compose a depositional sequence. However, because the basal contact of the Makganyene Formation has not been properly identified in previous work, no correct model has been proposed so far. Therefore correlations between the Griqualand West and the Transvaal basins, based on lithostratigraphic similarities and extrapolations of unconformities, have to be reviewed, especially since the publication of new radiometric ages contradict all previously proposed correlations. It is proposed here that the Transvaal Supergroup in the Griqualand West Basin represents a continuous depositional event that lasted about 200 Ma. The Makganyene glacial event occurred during changing conditions in the chemistries of the atmosphere and ocean, and in the continental configuration. A Snowball Earth event has been proposed as the causative process of such paleoenvironmental changes. However, evidence presented here of less dramatic glacial conditions, with areas of ice-free waters, implies an alternative to the Snowball Earth event. The paleoenvironmental changes are thought to represent a transition from an anaerobic to aerobic atmosphere, that was responsible for the global cooling of the surface of the Earth, Such a glacial event may have aided in the large-scale precipitation of iron and manganese in areas of intense upwellings.

This thesis explores the interface between community development via tourism and the field of development communication vis-à-vis a case study of the community-owned and privatelyoperated !Xaus Lodge in the Kgalagadi Transfrontier Park. The research is informed by Critical Indigenous Qualitative Research that employs interpretive research practices that aim to be ethical, transformative, participatory and committed to dialogue. The study valorises the voices of all lodge stakeholders analysing their expectations and how they negotiate the processes involved in the establishment and operations of the lodge. As a longitudinal study from 2006 until 2011 it focuses on the processes involved in transforming a failed poverty alleviation-built tourism asset into a commercial product with a range of benefits for the community partners. The processes involved are studied and shaped via participatory action research. This thesis generates a generalised public-private-community lodge partnership development communication model based on the findings of the !Xaus Lodge case study. The analysis of !Xaus Lodge is guided by development communication principles and practice such as the Communication for Participatory Development (CFPD) model, as well as the notion of pro-poor tourism (PPT). The applicability of these policies, approaches and models is problematised highlighting the complexity of development on the ground, particularly with indigenous and local communities. This study sets out the importance of cultural relativity in development projects whereby possible differences in the stakeholders‟ history, epistemology and ontology should be taken into consideration if a project is to negotiate both the demands of commercial viability as well as the symbolic and spiritual needs of the community partners. / Thesis (Ph.D.)-University of KwaZulu-Natal, Durban, 2011.

In the Upington region, there are three major- tectonic crustal provinces; namely the Kaapvaal Craton, Kheis and Namaqua tectonic provinces. The Eburnian-aged (early Proterozoic) Kheis Province developed along the western flank of the Archaean Kaapvaal Craton while the Kibaran-aged (middle Proterozoic) Namaqua Metamorphic Province, superimposed on the Eburnian-aged basement, developed to the east of the Kheis Province. The Namaqua Metamorphic Province is divided into the Gordonia and Bushmanland Subprovinces, the former being further subdivided into various tectonostratigraphic terranes. These are termed, from west to east, the Kakamas, Areachap, and Upington Terranes. The Upington Terrane includes fault bounded grabens with accompanied bimodal volcanism and sedimentation of the Wilgenhoutsdrif and Koras Groups. The Areachap Terrane consists predominantly of amphibolites generated in an island arc environment while the Kakamas Terrane is characterised by volcano-sedimentary sequences which have been extensively intruded by syn to late-tectonic predominantly I-type Keimoes Suite granitoids. The main styles of mineralisation correlate well with the various tectonostratigraphic terranes. Sedimentary exhalative massive sulphide deposits are characteristic of the Bushmanland Subprovince and are thought to be associated with the deposits at Aggeneys and Putsberg to the west of the area under investigation. These deposits are considered to have been deposited in an east-west-elongated intracontinental basin. The Kakamas Terrane is typified by granite-related mineralisation. In the eastern portion of the Kakamas Terrane, Sn-Wand base metal-bearing veins occur while pegmatites are developed in the western portion. These two styles of granite-related mineralisation is considered to reflect differing depths of formation due mainly to varying degrees of thrusting. The Areachap Terrane consists of volcanogenic massive sulphide deposits of the Besshi-type and is considered to have formed in a back-arc environment. In the Upington Terrane, the Wilgenhoutsdrif and Koras Groups consists essentially of minor Cu occurrences mainly disseminated within basalts and in structural trap sites. The possibility for sediment-hosted Cu deposits is not ruled out. More recent surface processes have led to uranium and gypsum deposits in pans, river beds and calcretes. Eburnian aged tectonic setting remains enigmatic. Kibaran-aged tectonics which best fits the metallogeny of the area under investigation is considered to be of a subduction zone from west to east formed by the collision of the Bushmanland "microcontinent" against the Kaapvaal Craton. Subduction fbrmed an island arc setting in which the massive sulphide deposits were formed in the Areachap Terrane while the Wilgenhoutsdrif Groups developed in a marginal basin. Further convergence led to collision of the two continents and underriding of the Bushmanland "microcontinent" which generated predominantly I-type granitoids represented by the Keimoes Suite. The level of emplacement of these granitoids is a reflection of the degree of foreland thrusting and produced shallower level Sn-W and base metal vein-type mineralisation closer to the suture zone and deeper level pegmatites further from the suture zone to the west. The final period of deformation is represented by northward lateral movement which created "pull apart" fault-bounded basins into which the Koras Group was deposited.