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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.
61

"Working in the grave" the development of a health and safety system on the Witwatersrand gold mines, 1900-1939

Smith, Matthew John January 1993 (has links)
This thesis analyses the establishment of a health and safety system on the Witwatersrand gold mines in the period between the end of the South African War and the eve of World War Two. The period has been chosen, firstly, because the South African War had seriously disrupted production and the industry virtually had to start up again from scratch; secondly, because it was during this period that mine and state officials began to seriously investigate the reasons for the appalling mortality and morbidity rates on these mines; and, thirdly, because during this period some improvements did occur which were significant enough to enable the industry to warrant the lifting, in the latter part of the 1930s, of the ban on tropicals, enforced since 1913 as a result of their extremely high mortality rate. In the first thirty years of the twentieth century about 93 000 African miners died disease-related deaths and in the same period some 15000 African miners were killed in work-related deaths. In attempting to establish why so many African miners died, the thesis attempts to identify the diseases and accidents that caused these deaths and considers what attempts were made to bring mortality and morbidity rates down. Whilst the thesis is neither a history of gold mining in South Africa nor an economic history of South Africa in the period 1901 to 1939, it nevertheless, as detailed in the first chapter, places the health and safety system within the context of the wider political and economic forces that shaped the mining industry in this period. The need for a productive and efficient labour force, vital for the industry'S survival during a number of profitability crises in this period, forced the industry to reassess compound structures, nutrition and eventually the health of its work force. These issues of compounds, work and diet are discussed in chapters two, three and four. Appalling living and working conditions led to a high incidence of pulmonary diseases - TB, silicosis and pneumonia - which were the principal killers on the mines. Attempts to cure or prevent their occurrence are discussed in chapter five. Fear of disruptions to production ensured that the mining industry eventually also devoted considerable resources to accident prevention, a theme which is discussed in chapter six. The thesis concludes that the mining industry for much of this period was able to determine the pace of change; neither state officials nor African miners were able to significantly alter the tempo. In fact the industry was so successful that it was able to convince a number of government commissions in the 1940s that the migrant system had to stay, to ensure the wellbeing of the miner. This meant that despite considerable time, money and effort being spent on establishing a health and safety system on the gold mines, the mining industry was still of the opinion that the health of their workers was best served if they were sent home.
62

Recovery of impregnated gold from waste mine timber through biological degradation

Martin, W. January 2000 (has links)
Thesis (MTech (Chemical Engineering))--Cape Technikon, 2000. / The large quantities of wood chips produced at mines from damaged underground timber contain gold that cannot be completely recovered by cyanidation. A fungus that can degrade a portion of the wood matrix will allow the gold that was previously locked up, to come into contact with the cyanide solution during beneficiation, thereby improving recoveries. The fungus Phanerochaete chrysosporium produces enzymes that use the organic compounds found in lignin as substrate. Consequently, the fungus is able to selectively break down lignin, which is one of the major components of wood. Chips sampled from Vaal Reef Mine contained between 2 and 5 mg/kg gold. The main source of gold in the chips was determined to be impregnated gold-bearing ore and discrete gold particles. Direct cyanidation resulted in around 60 per cent recovery prior to biological treatment. Despite relatively high weight losses caused to the chips as a result of treatment with Phanerochaete chrysosporium gold recovery only increased 10 per cent after 4 weeks treatment compared to direct recovery without treatment.
63

Geological and mineral economic evaluation and assessment of the Permian Karoo Supergroup coal assets owned by Eyesizwe Coal (Pty) Ltd, a Black empowerment company, South Africa

Wakerman, Boguslaw Wojciech 23 April 2014 (has links)
D.Phil. (Geology) / Please refer to full text to view abstract
64

Fault-controlled hydrothermal alteration of Palaeoproterozoic manganese ore in Wessels Mine, Kalahari Managanese Field

Burger, Albert Meiring 02 April 2014 (has links)
M.Sc. (Geology) / Refer to full text to view abstract
65

The influence of geological structure on seismicity and rockbursts in the Klerksdorp goldfield

Van der Heever, Paul 21 May 2014 (has links)
M.Sc. (Geology) / Please refer to full text to view abstract
66

Managers’ attitudes towards workplace trade unionism at a coal mining company

Mphahlele, Emmanuel 18 July 2013 (has links)
M.Comm. (Business Management) / Trade unionism and trade unions activities in South Africa’s labour relations system and workplaces has a long history of racial segregation characterised by confrontation and antagonism between the employer (management) and trade unions in the workplaces. However, in the South African contemporary labour relations environment the emphasis is more on creation of constructive and cooperative relations between the employer (management) and trade unions in the workplace. The literature study cites managers’ attitudes towards trade unions as one of the factor that could facilitate genuine interaction and promote productive cooperative management – trade unions relations in the workplace. The objective of this study was to assist in identifying and understating managers’ attitudes towards workplace trade unionism in the workplace utilising a coal mining company as a case study. For the purpose of investigating managers’ attitudes towards trade unionism and trade unions in the workplace, a literature review was conducted and the self-administered questionnaire was utilised as the research instrument to collect the primary data about managers’ attitudes towards trade unionism and trade unions in the workplace. The findings of the study reveal that most of the respondents generally harbour positive attitudes towards trade unionism and trade unions in the workplace. Another significant research finding of the study is the identification and existence of four factors underlying managers’ attitudes towards trade unionism and trade unions in the workplace. The factors identified relates to the awareness and understanding of the concept trade unionism and trade unions in the workplace, operational aspects in terms of perceived destructive and constructive role and function of trade unions in the workplace and lastly, management – trade union cooperation and relationship building in the workplace. Recommendations of the study were presented that will assist in improving and entrenching managers’ positive attitudes towards trade unionism and trade unions in the workplace.
67

The geology and evaluation of the "A"-reef at No.3 shaft, Western Holdings Mine, Welkom goldfield

Blamey, Nigel John Frederick January 1992 (has links)
The "A" -Reef occurs within the Aandenk Formation of the Central Rand Group, Witwatersrand Supergroup, in the Welkom Goldfield. It comprises the Witpan and Uitsig Reefs which are both oligomictic conglomerates, and are exploited for their gold content by Anglo American Corporation. The main Witpan channel complex is orientated in a NW-SE direction and occurs close to No.3 Shaft of Western Holdings Mine where it is currently being mined. The Witpan Reef varies in thickness from 7-220cm, with lateral facies changes controlling the thickness. Within the reef, gold is associated with degradation surfaces, carbonaceous material, increase in pebble sphericity, and channel edges. Two channel edges have yielded the best gold values on No.3 Shaft although the potential for further payable gold lies in the recognition of sieve conditions. The potential also exists for extensions of the "carbon"-bearing Uitsig channel currently being mined on President Steyn Mine. The palaeo-environment proposed for formation of the Witpan Reef is a braidplain that was partly reworked by a brief transgression. Ore evaluation using geostatistics was considered a valid technique as the dataset is sufficiently well structured. Semi-variograms in the channel and across-channel directions differ markedly. It was found that variograms of gold in cmg/t lacked sufficient structure for modelling, however, log semi-variogram modelling followed by simple log-kriging and back-transformation, proved to be the most successful method. Owing to the morphology and distribution of gold within the reef, a geologically based geostatistical valuation method is proposed. The potential for further exploration of "A" -Reef depends on a substantially higher gold price. In this event, exploration of Uitsig Reef to the southwest of the current mining area is recommended as well as a new exploration strategy for Witpan Reef.
68

Gold mineralization in archaean cherts and iron-formations a review of the economic geology

Bellamy, R E S January 1979 (has links)
The distribution of gold in igneous rocks and minerals is described and discussed. Not all the gold in igneous rocks is contained within early formed crystal lattices. Evidence that gold can be associated with late stage crystallizing phases is described. It is concluded that some of the gold in hydrothermal and volcanogenic deposits may have come from a primary magmatic source rather than having been leached from solid country rock. Gold is probably transported as chloride complexes at temperatures greater than about 300°C. At lower temperatures it is probably transported with other metals as sulphide and thio-sulphide complexes. The precipitation of gold from the transporting medium is brought about by changes in the physico-chemical conditions within that medium. Decrease in pressure is probably not a major cause of precipitation in volcanogenic environments. The geology of volcanogenic iron-formations is described and discussed, relative to the development of greenstone belts. Oxide facies iron-formations were formed in shallow oxidizing environments. They are associated with volcanogenic and clastic sediments. Sulphide facies iron-formations were precipitated in the deeper parts of geosynclinal structures. They are associated with mafic and ultramafic rocks similar to modern oceanic volcanic assemblages. Carbonate facies iron-formations were deposited in the regions between oxide facies and sulphide facies. Other banded iron-formations are found associated with base metal massive sulphide deposits related to arctype volcanic centres. These deposits are found in the regions where carbonate facies iron-formations were formed. Exploration for and exploitation of gold deposits in Archaean iron-formations are discussed. Geochemical exploration programmes are aided by the association of gold with trace amounts of base metals. Geophysical exploration methods that can be employed include magnetometer, I.P. and E.M. surveys. The metallurgical treatment of the ores should include "roasting" because a large proportion of the gold occurs as submicroscopic grains within sulphide mineral crystals.
69

Small-scale gold mining in southern Africa

Joubert, Barend Daniel January 1992 (has links)
The general characteristics of gold deposits are reviewed, and a classification of gold deposits based on mineability is proposed. Evaluation, mlnlng and beneficiation methods are briefly discussed. It is concluded that the most viable targets for small-scale companies comprise deposits that require the least pre-production time and expense. Great potential exists for the small-scale reclamation of gold from tailings dumps and abandoned mines in Southern Africa. There is also potential for developing new smallscale gold mines in the Archaean greenstone terranes of the Zimbabwean and Kaapvaal cratons.
70

The geology of the Welkom Goldfield with special reference to the "A", "B" and Beatrix Reefs

Dwyer, Gordon Bransby January 1993 (has links)
The first Witwatersrand gold deposits in the Orange Free State were discovered under younger cover rocks in the 1930's with the aid of drilling and geophysics. The Welkom gold deposits are found in the sedimentary rock sequences of the Central Rand Group, which represent unconformity bounded genetic packages. The structural configuration of the goldfield is one of a north to south trending synform that is split near it's axis by the De Bron and Homestead faults. The "B" Reef is a highly variable, erratically mineralised reef that lies on an unconformity at the base of the Spes Bona Formation. The "A" Reef Zone consists of several placers 1 including the "Reworked BPM" 1 the Witpan, the Uitsig, the Hanging Wall Grits and the Upper "A" Reef. The Beatrix Reef lies at the base of the Eldorado Formation on an unconformity surface overlying the Virginia Formation in the southern part of the Welkom Goldfield. The origin of gold in the Witwatersrand basin can be classified into the modified placer theory, the syngenetic theory and the epigenetic theory. From the distribution of basin edge unconformities it can be deduced that the Welkom fan depository was tectonically active on the western, southern and eastern margins during sedimentation. Palaeocurrent studies indicate that sediment was transported predominantly from the south and west. It is thought that the "B", "A" and Beatrix Reefs were all deposited in a braided stream environment. A multidisciplinary approach to ore evaluation of Witwatersrand deposits is considered to be the best method, where sedimentology, geostatistics and structural geology are used.

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