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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
1

Die geologie van die gebied Rooinekke-Matsap-Wolhaarkop in Noord-Kaapland met spesiale verwysing na die Koega-subgroep, Transvaal-supergroep

Van Wyk, Jacob Pieter 26 May 2014 (has links)
M.Sc. (Geology) / Please refer to full text to view abstract
2

A microstructural kinematic study of selected shear zones in the Hartbees River Thrust Belt, northeastern Namaqua Tectonic Province

Jackson, Christopher January 1992 (has links)
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.
3

The mineralogy and geochemistry of the Voëlwater banded iron-formation, Northern Cape Province

Tsikos, Harilaos January 1995 (has links)
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.
4

The early proterozoic Makganyene glacial event in South Africa : its implication in sequence stratigraphy interpretations, paleoenvironmental conditions and iron and manganese ore deposition

Polteau, Stéphane January 2005 (has links)
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.
5

The importance of vision and mission statements in promoting school effectiveness in Northern Province schools

Modiba, Solomon Ngwako. 15 August 2012 (has links)
D.Ed. / Schools have to provide quality education and maintain appropriate educational standards. Over and above that, schools have to deliver acceptable results. That will be the hallmark of schools being effective. Again, modem day schools can no longer be managed on an old fashioned way like in the past. School conditions have changed and keep on altering. Effectiveness and ineffectiveness could result from the changed teaching and learning environment. The main focus of this study is to investigate how public secondary schools in the Northern Province could be assisted to overcome ineffectiveness through the employment of vision and mission statements. Attention is placed on how clearly formulated vision and mission statements could be utilized to create effective schools. The main research question which has been driving the entire study is: What is the role and importance of clearly formulated vision and mission statements in developing and promoting school effectiveness in schools in the Northern Province? What are the perceptions of educators (principals and teachers) and parents with regard to the development and implementation of vision and mission statement in their schools? As already stated, the principal focus of the research is to address the problem of ineffectiveness as witnessed by some public secondary schools. The problem of ineffectiveness by schools is investigated from the point of view of vision and mission statements. This therefore, suggests that vision and mission statement have to be comprehended as interventionist strategy to assist ineffective schools to replace ineffectiveness with effectiveness. Vision and mission statements are located within a school as a learning organization. The reason for this is that in a learning organization every member feels an urge and drive to contribute his or her talent to the development of school as an organization. Again, in a school setting, these statements need to be approached as part of the school's comprehensive strategic plan. It is in that way that vision and mission statements could impact the school's organization structure, management process, management strategy, innovative ideas, values and culture. This will enable these statements to facilitate the occurrence of quality teaching and learning in schools.
6

Proposals to improve the implementation of the developmental appraisal system (DAS) in schools in the Northern Province schools

Mutshinyani, Avhatakali Hendrick. 13 August 2012 (has links)
D.Ed. / The focus of this research is on the proposals to improve the implementation of developmental appraisal in schools in the Northern Province (Limpopo). The research is aimed at probing the essence of developmental appraisal in schools, establishing the opinions and problems related to developmental appraisal in schools, establishing effective ways in which the school development team (SDT) can function for the support and development of educators and to make recommendations on the basis of the findings about the role developmental appraisal can play in restoring the culture of teaching and learning if well implemented. The central problem here is: How can developmental appraisal be implemented to satisfy both the appraisers and the appraises' expectations and lead to school improvement? The research starts with the background and orientation of the study giving the rationale of conducting this research. A focused literature study is then conducted, probing the essence of developmental appraisal in schools. The research strategy and the research methods follow a focused literature study. This was done against the background of a qualitative research using qualitative focus group interviews. Seven focus group interviews were held and tape-recorded with educators in the Northern Province (Limpopo). Transcriptions of tape-recorded interviews are included in this research as Appendices. The data of the report are then presented for further analysis. In analysing data, Miles and Huberman's approach was used, that is, data reduction, data display and conclusion drawings and verification. The research report is concluded with the findings and interpretation of data. Recommendations and topics for further research on the implementation of developmental appraisal in schools in the Northern Province (Limpopo) are finally given.
7

The metallogeny of the Upington and Kenhardt area, northern Cape

Boelema, Robert January 1995 (has links)
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.
8

Sonenergie as 'n plaasvervanger vir energie uit fossielbrandstof binne die landbousektor, op klein en medium skaal in die Noord-Kaap

Van Wyk, Gerrit 04 1900 (has links)
Thesis (MBA)--Stellenbosch University, 2015. / AFRIKAANSE OPSOMMING: Elektrisiteit is ʼn basiese bron van energie in hedendaagse huishoudings en besighede. Die behoefte na deurlopende elektrisiteit neem toe terwyl die huidige elektrisiteitsverskaffer, ESKOM, ook nie aan die huidige vraag na elektrisiteit kan voorsien nie. Verdere beperkings is die infrastruktuur. Die infrastruktuur is nie so ontwikkel dat elektrisiteit aan 100 persent van die bevolking verskaf kan word nie. Alle plase het nie toegang tot die huidige ESKOM roosterstelsel nie of dit is onprakties om ʼn dienslyn te bou vir die gerief van elektrisiteit. Gevolglik was die meeste boerderybedrywighede in die verlede afhanklik van dieselkragopwekkers. Die gebruik van sonenergie het egter aantrekliker geword en het moontlik meer ekonomies en prakties geword en bied ook ʼn deurlopende krag opsie. Sonstralingsvlakke in Suid Afrika is die hoogste in die wêreld. Die Noord-Kaap word ingesluit in daardie areas in SA wat uiters geskik is vir PV aanlegte. In lande soos Ethiopië en die VSA is sonenergie met PV-tegnologie met groot sukses aangewend in landbouomstandighede vir die voorsiening van elektrisiteit wat ook in SA met sukses aangewend kan word met die uiters geskikte sonbestralingsvlakke. Die grootste voordeel van sonenergie is die oorvloedige beskikbaarheid van die energiebron in SA. Verder is dit volhoubaar, omgewingsvriendelik, hernubaar en heeltemal gratis. Daar is geen bewegende onderdele nie, gevolglik is daar geen geraasbesoedeling nie en is die bedryfskostes van ʼn sonenergie stelsel baie laag. Die nadeel van sonenergie is dat PV-aanlegte slegs elektrisiteit kan opwek wanneer die son skyn. Energiebergingsisteme is nodig om hierdie nadeel te oorbrug of ʼn aanvullende energiebron soos wind moet gebruik word om die tekort aan te vul. Kapitaalspandering is die grootste hindernis in die oprigting van hernubare energiestelsels aangesien dit op een stadium spandeer moet word. Sonenergie is die gewildste energiebron binne die landbousektor in die Noord-Kaap en word deur 88.57 persent van die respondente gebruik terwyl slegs 28.57 persent van die respondente dieselkragopwekkers beskikbaar het as rugsteun fasiliteit vir elektrisiteitvoorsiening. Die belangrikste redes waarom daar oorgeskakel is na sonenergie, was om deurlopende elektrisiteit te verseker en die vermindering van tradisionele energieverbruik. Die studie toon dat sonenergie, oor ʼn 15 jaar leeftyd, ʼn derde van die koste van fossielbrandstowwe kos, alhoewel daar groter aanvanklike kapitaalspandering betrokke is wat as ʼn struikelblok gesien word. Die statistiek wat in die ondersoek versamel is dui daarop dat sonenergie suksesvol aangewend word om te voorsien aan die elektrisiteitbehoeftes van die respondente binne die Noord-Kaap geografiese gebied. Daar is egter geen twyfel dat sonenergie suksesvol, effektief, doeltreffend en ekonomies aangewend kan word as ʼn plaasvervanger vir energie uit fossielbrandstof, binne die landbousektor, op klein en medium skaal in die Noord-Kaap.
9

The establishment of an ABET centre in a rural school in the Northern Province of South Africa

Manamela, Enos 21 May 2014 (has links)
The aim of the study was to ident-fy issues involved in the establishment of an ABET centre in a rural secondary school. A case study of two schools with ABET centres and one without an ABET centre as well as a community college was undertaken. The procedure involved gathering information on how ABET was established and how it is implemented in the two schools. Observations and unstructured interviews were carried out in the four institutions. The information which was gathered was analysed to identify themes related to the establishment of an ABET centre. Factors which were investigated in the four institutions included among others, strengths, weaknesses, opportunities and threats (herein referred to as swot-analysis, see Abbreviations, Acronyms and Terminology). All the stakeholders such as ABET practitioners and governing bodies were requested to, for example, list and explain factors of 'swot' which they were experiencing. The analysis of the information gathered was used to inform the ’ researcher what factors to consider in es'tXL ishing an ABET centre in a rural school,, A procedural model for the establishment of an ABET centre is proposed in this study. The proposed model can be used not only by the sale rural school alone, but by other schools both in the rural and urban areas wishing to establish ABET centres in future. The decision, to :ise the model will depend on the evaluation by ABET implementers.
10

The co-design of a visual arts-based intervention within the community of the Olifants River valley in South Africa

Brand, Desiree January 2016 (has links)
Thesis (MTech (Design)--Cape Peninsula University of Technology, 2016. / The research was motivated by my lived experience in the Olifants River community of Namaqualand. In this community there are many diverse ethnic and social groupings with considerable potential to contribute to indigenous knowledge and creative practices. These groupings are, however, fragmented, with no platform for their varied and rich cultural assets to be displayed and acknowledged. In addition, the research was motivated by the call for a platform for the arts in the region. It is argued that visual art practice is an instrumental tool in the advancement of both creativity and social cohesion in this community. The research commenced with a pilot study, comprising workshops, which were run by art practitioners from various sectors in the region. Primary literature that influenced the emerging research design was that of Solomon (2007) as well as the holistic cultural viewpoints of Schafer (2014). The organic process of qualitative research methods as described by Ellingson (2009) was a natural personal directive. Body mapping was used during a preparatory phase that led to the creative exploration of community members’ own identity. Storytelling and dance were included in the design methodology since they enabled a psychosocial process of validating art practice as an economic asset within the community as well as enhancing social cohesion in the community. Crystallisation methods implemented in the process-driven body map workshops were held for grassroots -, town – and township sectors in the Olifants River valley. Each of the workshops comprised ten participants who were invited to participate in a subsequent do-designed collaborative event.

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