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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.
101

Genesis of karst-hosted manganese ores of the Postmasburg Manganese Field, South Africa with emphasis on evidence for hydrothermal processes / Genesis of karst-hosted manganese ores of the Postmasburg Manganese Field and the implications of related hydrothermal activity, Northern Cape, South Africa

Fairey, Brenton John January 2014 (has links)
The Postmasburg Manganese Field (PMF), located in the Northern Cape Province of South Africa, once represented one of the largest sources of manganese ore worldwide. However, the discovery of the giant manganese deposits of the Kalahari Manganese Field (KMF) led to the gradual decline in manganese mining activity in the PMF. Two belts of manganese ore deposits have been distinguished in the PMF, namely the Western Belt of ferruginous manganese ores and the Eastern Belt of siliceous manganese ores. Prevailing models of ore formation in these two belts invoke karstification of manganese-rich dolomites and residual accumulation of manganese wad which later underwent diagenetic and low-grade metamorphic processes. For the most part, the role of hydrothermal processes in ore formation and metasomatic alteration is not addressed. The identification of an abundance of common and some rare Al-, Na-, K- and Ba-bearing minerals, particularly aegirine, albite, microcline, banalsite, sérandite-pectolite, paragonite and natrolite in the PMF ores studied in this thesis, is indicative of the influence of hydrothermal activity. Enrichments in Na, K and/or Ba in the ores are generally on a percentage level for the majority of samples analysed through bulk-rock techniques. The discovery of a Ba-Mn arsenate/vanadate similar to gamagarite may also indicate that the hydrothermal fluid affecting the ores was not only alkali-rich but also probably contained some As and V. The fluid was likely to be oxidized and alkaline in nature and is thought to have been a mature basinal brine. Various replacement textures, particularly of Na- and Krich minerals by Ba-bearing phases, suggest sequential deposition of gangue as well as oreminerals from the hydrothermal fluid, with Ba phases being deposited at a later stage. The stratigraphic variability of the studied ores and the deviation of their character from the pigeon-hole-type classification of ferruginous and siliceous ores in the literature, suggests that a re-evaluation of genetic models is warranted. The discovery of hydrothermallydeposited alkali-rich assemblages in the PMF and KMF provides grounding for further investigation into a possible regional-scale hydrothermal event at least re-constituting the ores. Some shortcomings in previous works include disregard for the highly variable nature of the PMF deposits, the effects of hydrothermal activity of the ores and the existence of stratigraphic discrepancies. This study provides a single, broad model for the development of all manganese deposits of the PMF. The source of metals is attributed to all formations that stratigraphically overly the Reivilo Formation of the Campbellrand Subgroup (including the Reivilo Formation itself). The main process by which metals are accumulated is attributed to karstification of the dolomites. The interaction of oxidized, alkaline brines with the ores is considered and the overlying Asbestos Hills Subgroup BIF is suggested as a potential source of alkali metals.
102

Preservation or exploitation? : a study of the development of the mining rights legislation on the Witwatersrand goldfields from 1886 to 2008

Stott, Joan January 2009 (has links)
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.
103

Participation and paradoxes: community control of mineral wealth in South Africa's Royal Bafokeng and Bakgatla Ba Kgafela communities

Mnwana, Sonwabile Comfords January 2012 (has links)
Resource control as a form of community participation in the mineral economy has gained much recognition. One prevailing argument is that direct control of natural resources by local communities is an important precondition for equitable utilisation of the natural resource wealth, peaceful co-existence between mining corporations and indigenous communities, and congenial relations between local communities and the state. Studies have also shown that the absence of direct community control of mineral wealth remains a major factor in the communal resistance and socio-political conflict witnessed in the natural resource-endowed regions of countries such as Nigeria, Ecuador, Sierra Leone and the Democratic Republic of the Congo. However, little is known about mineral resource control at the community level. Does community control necessarily translate to equity? How does local involvement in the mobilisation of mining royalties benefit different segments of the community? Indeed, how do different segments of the community “control” the wealth? What is the specific model adopted to engender broad-based community participation in the utilisation of mineral wealth – and does it matter? These theoretical and practical questions were the impetus for undertaking this study in the Royal Bafokeng and Bakgatla Ba Kgafela – two platinum-rich ‘traditional’ communities in South Africa’s North West Province that have significant control over platinum resources in their territories. Utilising ethnographic data collected in the two study communities in 2008 and 2009, the thesis examines the character of community participation in platinum wealth utilisation; specifically, the conditions under which community participation promotes or hinders sustainable community development. The analysis uses a “three-dimensional participation ladder” conceptual scheme, based in part on Sherry Arnstein’s (1969) “ladder of citizen participation” and subsequent typologies of participation. Among the key findings of the thesis are that despite observed benefits, the interface of resource wealth and community development is fraught with tokenistic participation, elite-targeted grassroots anger, and local tensions – all linked to the contradictory nature of participation. The thesis further reveals that in some instances the challenge of platinum wealth-engendered community development tends to undermine existing customary and democratic spaces for participation, and that this is exacerbated by community-level issues such as poverty and inequality. The findings of the study compel a shift of analytical focus from conflict as an epiphenomenon of collective community exclusion and deprivation (as in the case of many natural-rich countries in Sub-Saharan Africa and elsewhere), to conflict as also resulting from collective community inclusion (in natural resource utilisation). At the policy level, the study generates insights that will, hopefully, assist mineral resource-endowed countries, such as South Africa, in dealing with the challenge of developing appropriate policy frameworks for regulating business and social partnerships between local communities and mining corporations, and within resource-rich communities themselves.
104

An assessment of heavy metal pollution near an old copper mine dump in Musina, South Africa

Singo, Ndinannyi Kenneth 06 1900 (has links)
Heavy metal pollution in water and soil is a serious concern to human health and the associated environment. Some heavy metals have bio-importance but the bio-toxic effects of many of them in human health are of great concern. Hence, there was a need for proper understanding of the concentration levels of these heavy metals in ground water and soil around the community residing in the vicinity of the defunct mine. Mining has become prominent in this area because of the existence of copper lodes, veins and veinlets. It was therefore necessary to assess these selected metals associated with copper mining as their concentration has a tendency to affect the environment and human health. The objective of this study was to establish the levels of lead (Pb)-zinc (Zn)-copper (Cu)-arsenic (As)-nickel (Ni) metals in ground water and soil associated with an old copper mine in the vicinity of the township and to compare them with the South African and international standards in order to safeguard the health of the community using such water for drinking purpose. Clean sampling plastic bottles were used to collect water from five water boreholes being used at present. Water samples were filtered using membrane filtration set LCW (0.45 μm). The samples were digested sequentially with different procedures for the total metal concentration. Concentrations of four metals commonly associated with Cu mining were examined at five different water boreholes which are used for drinking and industrial purposes. Flame Atomic Absorption Spectrophotometer (Perkin Elmar S/n 000003F6067A, Singapore) was used to analyze metals in water samples at Eskom Ga-Nala Laboratory: pH, electrical conductivity and turbidity were analyzed using an auto titrator meter (AT- 500,Japan), conductivity meter (Cole-parmer® YO-19601-00) and turbidity meter (AL 250TIR, Agua lytic, German) respectively. Soil samples were collected from the selected areas where human health is of a serious concern, and a hand held auger drill was used to recover samples, while shovels were used to prepare the sampling area. The samples were sieved up to 63.0 μm particle size and digested with aqua-regia. Flame Atomic Absorption Spectrophotometer (Model: AA400; Year: 2008; Manufacturer: Perkin Elmer; Germany; Serial no: 201S6101210) was used at the University of Venda Laboratory to analyze soil from the study area for possible heavy metal contamination due to the defunct Cu mine in the area. v The results showed variation of the investigated parameters in water samples as follows: pH, 6.0 to 7.51; EC, 70.0 to 96.40 μS/cm and turbidity, 1.05 to 4.56 NTU. The mean concentration of the metals increased in the followed order: Pb<Cu<As<Ni. Ni is the most abundant in the ground water determined with value of (6.49 μg/g). The observations have confirmed that most ground water contains an appreciable quantity of Ni. The mean value of As in water is (4.20 to 4.84 μg/g), Pb and Cu have (2.13 to 2.58 μg/g) and (1.52 to 2.52 μg/g) respectively. For soil samples, the mean concentration of the metals increased in the following order: Pb<Cu<Zn<As<Ni. Pb ranged from (0.023 to 0.036 μg/g) followed by Cu (0.28 to 0.45 μg/g) then Zn (0.026 to 0.053 μg/g), the mean range of As in soil ranged from (0.054 to 0.086 μg/g). However, some studies show much higher contamination of As from the natural sources and Ni with (0.057 to 0.144 μg/g) lastly. Accumulation of heavy metals in soil is of concern due to their toxic effects on human and animals. The quality of ground water from the five boreholes studied was satisfactory with turbidity (T), electrical conductivity (EC) and heavy metals (HM’s) below the WHO limit. The water therefore may, according to the WHO Standards be safely used as a drinking water. The concern lies on pH which was slightly (0.5) below the standard. There is a serious need to monitor the ground water which is now used for drinking purposes. This study revealed that heavy metal pollution in soil from the abandoned Cu mine in Musina is a threat to the health of the community. Although pollution was between medium and low in the contamination index, it is therefore important for the Musina Municipality or mine owner of Musina (TVL) Development Co Ltd copper mine to advocate possible remedial actions which will safeguard the environment and human health. The tailing at Musina’s old Cu mine have high pH and they lack normal soil stabilization processes, as a result the tailing does not develop a good plant cover. Pollution of the ground water resources is also evident in the study area where there is seepage or ingress of polluted water to the underground aquifers. Small-scale mining in Musina is causing further degradation to the environment but it supports the South African Waste Hierarchy by promoting the reuse and recycling of the tailing and mine dumps for the production of bricks. Mine workers are exposed to the above mentioned toxic heavy metals daily. Medicine will not help stop the poisoning. The only way to stop the metal poisoning is to stop being exposed to the heavy metals. / Environmental Sciences / M. Sc. (Environmental Management)
105

Development of guidelines for dealing with morphological and environmental impacts of sand mining along the Nzhelele River, Limpopo Province of South Africa

Mathada, Humphrey 22 January 2015 (has links)
MENVSC / Department of Geography and Geo-Information Sciences
106

Variation of the coal stratigraphy and characterization of the Soutpansberg Coalfield, Limpopo Province, South Africa

Mawila, Edith Elizabeth Tintswalo 20 September 2019 (has links)
MESMEG / Department of Mining and Environmental Geology / The future of energy in South Africa depends on coal as it is one of the cheapest and most affordable sources of energy; however, some of the coal is uneconomical to mine due to the thickness and depth of the coal seams. For many years the coal resources of the Soutpansberg Coalfield remained untapped and limitedly researched and with the coal resources running out in the other coalfields, the Soutpansberg Coalfield remained the bright coalfield of tomorrow in South Africa. Coal seams in the Soutpansberg Coalfield occur within the Madzaringwe Formation. Three coal basins have been identified in this coalfield, are the Venda-Pafuri, Tshipise and Mopane. Sedimentological basin analysis of the coal stratigraphy and characterisation of the Soutpansberg Coalfield in the Makhado area, Limpopo Province was investigated within the farms of Rissik, Fannie, Duel, and Lurkin. The main purpose of the study was to establish the variation of the coal stratigraphy and how coal influenced the stratigraphy within the area. Fieldwork involved core logging and core sampling from the different farms within the Makhado coal area, while laboratory work included petrographic studies, investigation of the physical and chemical properties of coal. Core logging revealed the occurrence of coal zones where coal seams were intercalating with mudstones, but rarely with siltstone that formed the footwall of coal. Rarely was coal intruded by dolerite dyke as was the case along borehole W6610001. Core logging further revealed the sedimentary structures in the lithologies and the depth at which different lithologies were intersected. From these sedimentary structures, the environment of coal deposition was deduced supported by the geochemical analysis of major oxides and trace elements. Correlation of boreholes along the strike showed that the shale and mudrock were the predominant rocks within the coal horizon leading to the conclusion that these were the coal host rocks. Whole rock geochemical analysis was undertaken, using X-Ray Fluorescence Spectroscopy in order to establish the rock types and their trace element contents. The collected samples were analysed at the University of Venda, Department of Mining and Environmental Geology Laboratory, Siza Coal Services in Secunda and Council for Geoscience. The study indicated that the coal seams of the Soutpansberg Coalfield were deposited within the floodplain of a mixed-load fluvio-deltaic (fluvial and braided) systems. This sedimentary channel has been the major influence on the development of the coal seams. Locational changes in sedimentary facies above and below the coal seams within the study area has caused variations in the rates of compaction and subsidence which influenced the coal basin morphology and the coalification pattern. These two parameters (variations in the rates of compaction and subsidence) controlled the coal quality parameters, and coal seam thickness as well as the coal composition. The study confirmed that coal quality and thickness vary markedly from place to place in this coalfield due to varying local depositional environments. Most of the drill holes intersected mainly 3 coal seams, although in some cases either 2 or 5 seams were intersected. The thickest coal seam (borehole F578002) was 8 m. It was concluded that the coal was sub-bituminous to bituminous coal rank class (medium-volatile bituminous coal rank class). The coal had low moisture content ranging from 0.7-0.8%, and ash content ranging from 21.4-32%. The fixed carbon and volatile matter values of the coal samples ranged from 42.5 to 50.4% and from 25.2 to 27.4% respectively. The carbon and hydrogen were the main principal combustible elements in coal, however; carbon is the predominant one based on weight, constituting about 5.3% (the lowest) to 70.3% (highest) of the total. Due to the nature and thickness of the coal seams we conclude that this coal was economical to be mined and can be used for electricity generation and in cement grinding plants. A graph of coal gas concentrations over combustion time showed that methane (CH4) and carbon dioxide (CO2) had high gas concentrations, amounting to 1.75% and 1.70% respectively. / NRF
107

Class, colour consciousness and the search for identity : blacks at the Kimberley diamond diggings, 1867-1893

Lawrence, Paul Gilbert January 1994 (has links)
Bibliography: pages 168-176. / The discovery of diamonds in the Kimberley area was to have far reaching consequences, not only for the region but the entire sub-continent. In addition to the hundreds of individual diggers, mainly white, who converged on this arid corner of southern Africa, there appeared also, in a remarkably short time, a complete infrastructure of urban facilities to serve their needs. Perhaps the most unique component of the otherwise colonial population was the massive influx of migrant Africans in response to the insatiable labour demands of the diamond mines. We examine the interplay of racial attitudes and conflicts and the ambiguous position of the black elites in the diverse groups of 'colonial' or 'civilised' Africans, 'Cape Coloureds', Muslims and Indians who came to Kimberley to seek their fortune. It is our contention that it was this ambiguity which was to provide a spur to black political activity. We closely consult contemporary accounts, official documentation and local newspapers, all of which faithfully record the ebb and flow of the state of racial relations. Never a typical microcosm of colonial urban society because of the extraneous factor of economic competition for limited employment and resources, social relationships in Kimberley gradually changed until the essential confrontation was not between colonials and the rest, but rather more specifically between blacks and whites. While the early history of Kimberley was marked by the virulent racism of white· diggers resisting black competition, the ensuing years were to witness a more tranquil period of racial co-existence. This tranquillity proved to be only the calm before the storm. We show how a series of crises strained relations between blacks and whites to breaking point. The failed rebellion by indigenous blacks, the smallpox epidemic during which the Muslim community incurred the wrath of white public opinion by failing to adopt western preventative measures, a revolt - the Black Flag Revolt- by militant white diggers and the effects of the new recruitment policies of the mining companies in the 1880s, which opened jobs to cheap black workers, all resulted in an increasing polarisation of race relations in Kimberley. We argue that where before official documents and newspapers had shown a class discrimination directed against migrant African labourers, this changed over time to become a negative portrayal of blacks in general. The effect of the emergence of this negative stereotype was to separate whites and blacks in many facets of life in the mining centre.
108

The stratigraphy, structure, and gold mineralization of the Jamestown and Sheba Hills areas of the Barberton Mountain Land

Anhaeusser, C. R. (Carl Robert) 28 May 2015 (has links)
No description available.
109

Methane emissions assessment in South African coal mines and their potential utilizations

Maseko, Lucky Albert 27 September 2012 (has links)
M.Sc.(Eng.), Faculty of Engineering and the Built Environment, University of the Witwatersrand, 2011
110

The evolution of large technical systems in the Waterberg coalfield of South Africa: from apartheid to democracy

Ballim, Faeeza January 2017 (has links)
A thesis submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, in fulfilment of the requirements for the Degree of Doctor of Philosophy. Johannesburg, March 2017. / This thesis follows the development of a particular set of large technical systems in South Africa from the late apartheid era into the age of democracy. During apartheid technological prowess, upheld by the network of state corporations or parastatals, bolstered the authoritarian rule of the white minority government in South Africa. The economic and political liberalisation of the late 1980s challenged the power of the parastatals and altered the underlying rationale of infrastructure development. In particular I describe the transformation of Iscor and Eskom, two of the country’s major parastatals, and their activities in the Waterberg coalfields, an isolated region on the country’s north-western border. While Eskom’s activities in the region began in the 1980s they gained public notoriety with the construction of the Medupi power station two decades later. The obstacles that Eskom faced at Medupi represent the main challenge of developing large technological infrastructures in the democratic, post-colonial order, where the fruits of infrastructure development demand to be spread beyond the bounds of an elite minority. But the eventual completion of some power generating units in 2015 at Medupi demonstrates that failure is not inevitable. I argue that this success is due to the fact that the autonomous parastatal network negotiated the political and economic liberalisation of the early 1990 by incorporating the changing socio-political conditions into its operations. The parastatal network retained a momentum, in the sense first described by the historian of technology Thomas Hughes, which was also a product of the “locked-in” nature of investment in the infrastructure project. Because of the large capital investment required for the infrastructure development, proceeding tenaciously against the odds to see the project to completion was cheaper than retreat for those involved. / MT2018

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