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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

Aspects of the petrochemistry of the Phalaborwa Complex, northeastern Transvaal, South Africa

Eriksson, Susan Camenisch January 1982 (has links)
A Thesis Submitted to the Faculty of Science, University of the Witwatersrand , Johannesburg for the Degree of Doctor of Philosophy / The Phalaborwa Complex, northeastern Transvaal, South Africa, consists of the main body of clinopyroxenites and subordinate phoscorite, carbonatite and syenite which is surrounded by numerous pipe-like bodies of syenitic compositions and rare clinopyroxenites. Clinopyroxenites of the main complex are characterized by cumulus textures formed by separation and accumulation of coprecipitating clinopyroxene, apatite and phlogopite. Potassium feldspar is an intercumulus phase in feldspathic pyroxenite. "Inch-scale" layering of clinopyroxene, apatite and phlogopite formed as in situ cumulus layering near the outer contact of the complex early in the cooling of the magma. Breccias of monomineralic assemblages such as glimmerite and massive pyroxenite reflect breaking up of early formed rocks by magmatic currents. Clinopyroxenes from clinopyroxenites are characterized by Fe/(Fe+Mg) = 0.07-0.29, low T i 02 (0.00-0.25%), A 120 3 (0.00-1.63%), N a 20 (0.00-1.06%), and Cr, and high Wo component and Sr. Micas from pyroxenites have Fe/(Fe+Mg) = 0.12-0.28, low T i 02 (0.17-1.73%) and have reverse and normal pleochroism and increasing A1 with increasing Fe/(Fe+Mg). Mineral compositions among feldspathic, massive and micaceous pyroxenites overlap; no zonation of the complex from outer contact inward is discernible with respect to the Fe and Mg content. However, phlogopites in "inch-scale" layering have low Fe/(Fe+Mg) of 0.12 and have reverse pleochroism due to F e 3+ entry into the Al-deficient tetrahedral site. Micas from phoscorite and carbonatites have reverse pleochroism, Fe/(Fe+Mg) = 0.05-0.58, low T i 02 (0.00-0.84%) and decreasing A1 with increasing Fe/(Fe+Mg). Olivines range from F o79 to F o91 and have very low Ni content (<0.06% N i O ) . Olivines interpreted as xenocrysts have Fo 84 to F o 8 7 . One of the olivine xenocrysts has an NiO content of 0.29%. Minerals from carbonatites have initial 87S r / 86Sr ratios of 0.70393-0.70623 and 0.71022 and minerals from clinopyroxenites have values of 0.71152-0.71242. Smallscale inhomogeneities exist within samples. Postcrystallization processes can account for variations within samples, but cannot account for variations within a rock type or for raising initial 87S r / 86Sr ratios of pyroxene from 0.7039 to 0.7115. Magmas forming pyroxenites and some carbonatites were generated in a high Rb/Sr mantle from isotopically distinct sources. Hence, liquid immiscibility and differentiation are not viable mechanisms for relating these rocks to one another. Mixing of magmas and assimilation of crust may account for isotopic variations within a rock type. U-Pb dating of uranothorianite and baddeleyite from phoscorite and carbonatite yields an age of 2047+11/-8 m.y. Rb-Sr dating of phlogopites gives widely disparate apparent ages. Nine phlogopites yield an isochron of 2012 + 19 m.y. One sample of phlogopite gave ages of 1661-2360 m.y. in nine different determinations. Older micas may be present in the Phalaborwa complex. Based on the two methods, a best age of the Phalaborwa complex is 2030 + 18 m.y. Two of the syenite pipes, Kgopoeloe and Spitskop, show different levels of emplacement. Kgopoeloe is highly brecciated from a fluid derived from the syenite. Spitskop contains minor breccia and represents multiple injection of syenite. At Spitskop, inward crystallization of the second syenite forms a ring syenite and central syenite; both syenites have cumulus enrichment of minerals. Feldspathic pyroxenite of the Guide Copper Mine is cogenetic with the pyroxenites of the main complex and contains clinopyroxenes with oscillatory zoning. Fluctuations in f02 may be attributed to formation of an immiscible sulphide liquid. Multiple intrusion of the Phalaborwa Complex is proposed. Initial injection of potassic, probably ultrabasic, liquid formed the pyroxenites. A second intrusion of low-silica, carbonate-rich magma formed phoscorite and banded carbonatite. A third intrusion of carbonatite liquid formed the transgressive carbonatite. Magmatic, cumulus processes dominated the formation of the main complex. The syenites of Kgopoeloe and Spitskop are not cogenetic with rocks of the main complex. / AC2017
2

Metaalbewerkers van Phalaborwa (Afrikaans)

Pistorius, Julius Cornelius Christiaan 19 March 2013 (has links)
In 'n streekopname in 'n gebied rondom Loolekop wat die sentrale karbonatietpyp van die Palaborwa Stollingskompleks vorm, is sowat vyftig histories bekende terreine opgespoor wat in drie groepe verdeel is op grond van die metaalbewerkings- en woonterreinoorblyfsels van die terreine. Steekproefopgrawings is op elf terreine uitgevoer ten einde meer van die aard en omvang van metaalbewerking in die navorsingsgebied, nl. die Loole-terreinkompleks vas te stel, terwyl die argeologiese oorblyfsels ook met behulp van etnohistoriese inligting aangaande vroeë baPhalaborwa-gemeenskappe geskakel is. Opgrawings toon dat yster en koper in die navorsingsgebied bewerk is met behulp van verskillende prosesse en in verskillende tipes oonde. Die bewerking van die metale toon sekere voorkomsgebiede - hoewel dit beïnvloed kon word deur die vernietigingswerk van moderne mynbedrywighede. Mondelinge oorlewering verbind die metaalbewerkers met verskillende vroeë baPhalaborwa-gemeenskappe, terwyl die groepe terreine in 'n relatiewe chronologie georden word met behulp van radiokoolstofdaterings, historiese inligting en die kenmerke van terreine. ENGLISH : In a regional survey in an area around Loolekop which represents the central carbonatite pipe of the Palaborwa Igneous Complex, about fifty historical known sites were identified and divided into three groups according to the metalworking and occupational remains on these sites. Test excavations were conducted on eleven of the sites in order to gain information on the nature and extent of metalworking in the research area, viz. the Loole site complex, while the archaeological remains were also coupled with ethnohistorical evidence regarding early baPbalaborwa communities. The excavations indicated that iron and copper had been worked in different processes and with different furnaces. The working of the metals indicate certain areas of preference - although this may have been influenced by the destruction of archaeological sites due to modern mining activities. Oral tradition couples the metalworkers with different early baPhalaborwa communities, while the different groups of sites were arranged in a relative chronology aided by radiocarbon dating, historical information and the characteristics of sites. / Thesis (DPhil)--University of Pretoria, 2013. / Anthropology and Archaeology / unrestricted
3

The palaeomagnetic significance of the Bushveld Complex and related 2 Ga magnetic rocks in ancient continental entities

Letts, Shawn Andrew 26 May 2008 (has links)
The Kaapvaal Craton was the scene of two major magmatic events around 2.0 Ga, namely the Bushveld Complex and the Phalaborwa Complex. Both complexes have been the subject of numerous palaeomagnetic studies during and prior to the 1980s. Despite these studies, systematic inconstancies for emplacement ages, in particular for the Bushveld Complex, have been found between the palaeomagnetic findings and well constrained ages. The greatest concern with the Bushveld Complex results are the large spread in pole positions previously determined for the different zones. This has been interpreted in prior studies to indicate that the Bushveld Complex was emplaced and cooled below the Curie temperature of magnetite over a time span of 50 my. The results obtained previously for the Phalaborwa Complex appear to be out of position (~16°) with respect to those for the Bushveld Complex. This is of concern because new geochronological data show that the Rustenburg Layered Suite of the Bushveld Complex was emplaced approximately 1 my after the Phalaborwa Complex. These inconsistencies have prompted the current re-investigation of the palaeomagnetic results for both the Bushveld Complex and the Phalaborwa Complex. New palaeomagnetic data collected from all zones of the Rustenburg Layered Suite from the Eastern, Northern and Western Lobes of the Bushveld Complex, yielded palaeomagnetic poles that eliminated the spread in the apparent polar wander path. This observation is in agreement with precise age data, constraining the time period of emplacement of the complex to ~ 6 my. Resulting beddingcorrected high blocking components from all zones produced better groupings, thereby supporting a primary magnetic signature and indicating that the complex was intruded in a near-horizontal position. Dual polarities identified within each zone of the complex and positive reversal tests have identified one of the oldest known reversals of the Earth’s magnetic field. iii Palaeomagnetic data from the Phalaborwa Complex have produced a pole position that is in close proximity to those obtained from the coeval Bushveld Complex. In an attempt to achieve a better understanding of tectonic events occurring in the Kaapvaal Craton a number of dual polarity dykes within the Bushvled and Phalaborwa Complexes were palaeomagnetic analysed. Results revealed that the acquired pole positions are in agreement with ~1.9 Ga dykes, indicating the possibility that the dykes occurring in both complexes are part of the same magmatic event. Palaeopoles generated during this study were used in refining the Kaapvaal Craton apparent polar wander path around 2.0 Ga, and in conjunction with other welldefined 2.0 Ga poles for the Kaapvaal Craton, a robust cratonic pole was produced that was used in Precambrian palaeographic reconstructions with emphasis on the postulated Vaalbara continent and the Columbia supercontinent. Palaeomagnetic reconstruction derived in this study has cast doubt on the existence of the Vaalbara continent at 2.0 Ga. Although, some support is given to the existence of the Columbia supercontinent at the same period.
4

Bioassessing the impact of water quality on the health and parasite composition of Oreochromis Mossambicus at the Phalaborwa Industrial Complex (PIC) and the barrage (Olifants river) in the Limpopo Province,South Africa.

Ramollo, Phetole Peter 12 1900 (has links)
Thesis (M.Sc)--University of Limpopo, 2008. / Three sites at the Phalaborwa Industrial Complex (PIC) and one site at the Phalaborwa Barrage in the Olifants River were selected to illustrate the possible influence of different water quality parameters on the health and parasite composition of the Mozambique tilapia (Oreochromis mossambicus). Ten fish were collected seasonally at each site using gill nets of different mesh sizes. Selected water quality variables were determined at all the sites to establish possible differences in water quality between the sites. Hosts were examined for mobile ectoparasites, weighed and measured. Blood samples were drawn and skin smears were made. Fish were killed, dissected and all external and internal organs were examined as prescribed in the fish health assessment index (HAI). The condition factor was determined for each fish population from the different sites. All parasites were collected, fixed and preserved using standard methods. A parasite index(PI), abundance, prevalence and mean intensity of the parasite infestations were calculated.Results obtained for the system variables (pH, water temperature and dissolved oxygen) indicated that the pH levels and water temperature fell within the target water quality range (TWQR) for aquatic ecosystems, but the dissolved oxygen recorded during most of the surveys were below 5mg O2 l-1 which may adversely affect the functioning and survival of biological communities. The mean turbidity values were high at sites A, C and D (caused by fine particles such as silt, clay and organic matter). The total dissolved solids (TDS) and the electrical conductivity (EC) were very high at sites B and C throughout the study. The total water hardness and salinity were also very high at sites B and C which can be attributed to the mine tailings water as well as the geology of the region. The cations (calcium, magnesium and potassium) and anions (chloride, fluoride and sulphate) were above the TWQR for aquatic ecosystems at all sites. The fluoride and sodium levels were high at sites B and C. All the major ions contributed significantly to increased levels of TDS, salinity and EC at sites B and C. The nitrogen and phosphate levels indicated that there was an influx of nutrients into the four sampling sites at varying degrees, which can have an effect on eutrophication conditions at the sampling sites. Trace and heavy metal concentrations differed significantly between all the sites. Aluminium, iron and manganese levels were within the TWQR for aquatic ecosystems at all sites. Copper, lead and zinc levels were above the TWQR and sometimes above the chronic and acute effect values for aquatic ecosystems throughout the study (except for lead concentrations at site A). Thus, the mining activities do affect the water quality at sites B and C adversely in terms of the dissolved salts, nutrients and trace and heavy metals (with the water at site C more impacted than that of site B). The toxicity of some metals is however, dependant on the pH (if it changes to be more acidic, some metals may become toxic) and water hardness of the specific site. The lowest population HAI values (indicating healthier fish populations) were mostly recorded from sites A and D (the sites with better water quality) and the highest at site C(the site with poorer water quality) for three surveys. The high HAI values at site C can mainly be attributed to liver discoloration and abnormal haematological parameters. The fish condition factor values ranged from 0.92 to 1.2 with the lowest mean value recorded at site A and the highest mean value recorded at site B. But, the condition factors indicated that the fish from all sites were generally in good health. The values attained for the haematological parameters, liver discolorations, fins (due to parasitic infestation),abnormal gills, as well as the type of parasites present in/on the fish, were the most indicative parameters in the HAI. No abnormalities in the kidneys, opercules and spleens of fish were observed at any of the four sampling sites during this study. Results from the HAI thus indicated that the fish population from site C was more affected by the water quality (with a higher HAI) compared to the fish populations from the other sites. Also, dissimilar water quality at the different sites affected the health of fish differently. The results recorded for the HAI of the different fish populations thus substantiate the results obtained from the water analysis, indicating that fish from site C (with the poorest water quality) was more affected by their environment. The parasites recorded from O. mossambicus were all site-specific and seem to be moderately influenced by the water quality of the different sites. Some groups, e.g. monogeneans were more affected by the differences in water quality than other parasitic groups. The following ectoparasites were recorded: Cichlidogyrus sp. from the gills and Lernaea cyprinacea and Argulus japonicus from the skin. Endoparasites included digenean larvae from the skin (“black spot”) and gills, Neutraclinostomum larvae in the branchial region, Diplostomum metacercariae from the eyes and swimbladder,Diplostomum tregenna from the brain, dilepidid cestode larvae from the liver and outer surface of the intestine, Contracaecum larvae from the body cavity and sinus venosus of the heart, adult acanthocephalans from the intestine, and pentastomatid larvae of two genera (Subtriquetra rileyi and Alofia sp.) from the swimbladder. The hypothesis that the number of ectoparasites will be lower in more polluted water and the number of endoparasites will be higher was well supported for O. mossambicus at all sites except at site C during Spring survey. The PI for endoparasites was higher at all the mine sites (except during Spring) but similar results were also obtained at sites A and D (the less impacted sites). However, all sites tested during this study were impacted to a lesser or higher degree and the PI for endoparasites can thus be higher at all sites. Some ectoparasites (i.e. Lernaea cyprinacea) were present in high numbers at the more polluted site (site C), but the abundance of monogeneans (also ectoparasites) was most of the time lower at sites B and C, suggesting that monogeneans have been strongly influenced by the poorer water quality at these sites. The specific water parameter/s that influenced the abundance of certain ectoparasites needs further investigation which would most probably best be tested under controlled laboratory conditions. In conclusion, all sites sampled during this study were contaminated to some degree with sites B and C more impacted than the other two sites. The water quality results thus confirmed the results obtained using the HAI and to a lesser extent, the PI. The water quality differed between the four sites and had dissimilar impacts on the health of O. mossambicus and the prevalence of some parasites at the different sites. / the National Research Foundation,the Sasol Nitro
5

Piroksenitiese gesteentes van die Phalaborwa-kompleks met verwysing na die verspreiding van fosfaat

Fourie, Petrus Johannes 20 October 2014 (has links)
M.Sc. (Geology) / Please refer to full text to view abstract
6

Evaluating telemetry system of the Phalaborwa water treatment works process in Lepelle northern water

Majadibodu, Levy Lehu January 2021 (has links)
>Magister Scientiae - MSc / Water is a strategic resource critical for basic human needs and for sustaining key economic sectors, including various emerging small businesses. The significance of water to everyday life become apparent mainly during periods of acute water shortages because of increasing population, industrial developments, droughts, and natural disasters that threatens the assurance of water supply. With the growing complexity of water supply challenges faced by the Phalaborwa WTW, there is a need to deploy technology and other means available to improve the provision of water and sanitation services. The aim of the study was to evaluate the telemetry system for managing the Phalaborwa WTW water supply process. / 2022
7

Community participation and development in South Africa : the case study of Ward Committees as an effective vehicle for public participation in Ba-Phalaborwa Municipality

Mhlari, Mzilela Conride 05 1900 (has links)
This study examines the role of Ward Committees in facilitating “authentic” public participation, with particular reference to Ba-Phalaborwa Municipality. The key question of the study is whether Ward Committees serve as effective mechanisms to promote public participation in the local sphere of government in South Africa. To answer this question, this research project focuses on the composition, functioning and responsibilities of Ward Committees, and how these contribute to effective public participation. This is important because one of the mandates of local government in the post-apartheid era in South Africa is to promote local democracy through the participation of communities. The empirical findings of this research project reveal that Ward Committees are confronted with a multitude of challenges where their functioning tends to be compromised. This has led this research to recommend the improvement of capacity among Ward Committees as a way of enhancing public participation. / Development Studies / M.A. (Development Studies)
8

Community participation and development in South Africa : the case study of Ward Committees as an effective vehicle for public participation in Ba-Phalaborwa Municipality

Mhlari, Mzilela Conride 05 1900 (has links)
This study examines the role of Ward Committees in facilitating “authentic” public participation, with particular reference to Ba-Phalaborwa Municipality. The key question of the study is whether Ward Committees serve as effective mechanisms to promote public participation in the local sphere of government in South Africa. To answer this question, this research project focuses on the composition, functioning and responsibilities of Ward Committees, and how these contribute to effective public participation. This is important because one of the mandates of local government in the post-apartheid era in South Africa is to promote local democracy through the participation of communities. The empirical findings of this research project reveal that Ward Committees are confronted with a multitude of challenges where their functioning tends to be compromised. This has led this research to recommend the improvement of capacity among Ward Committees as a way of enhancing public participation. / Development Studies / M.A. (Development Studies)
9

Problems encountered by Foskor mine workers with the use of personal protective equipment

Pilusa, Mogale Ludwick 30 November 2008 (has links)
The purpose of this study was to find out problems encountered by Foskor Mine workers in Phalaborwa with the use of personal protective equipment and also to find out how these problems can be prevented or solved. A quantitative research study was done using a questionnaire as a data gathering tool on workers who are exposed to occupational injuries and illnesses and who use personal protective equipment for their protection. The findings revealed that even though workers were using personal protective equipment they still got occupational injuries and illnesses. They also had problems with their protective equipment like incompatible types of personal protective equipment, such as weight where heavy personal protective equipment like boots were issued and very hot or cold personal protective equipment incompatible with the temperature of the environment. Some personal protective equipment like gloves were of a wrong size and caused allergy. In some instances unavailability of or unsuitable personal protective equipment posed challenges to these workers. / Health Studies / M. A. (Health Studies)
10

Problems encountered by Foskor mine workers with the use of personal protective equipment

Pilusa, Mogale Ludwick 30 November 2008 (has links)
The purpose of this study was to find out problems encountered by Foskor Mine workers in Phalaborwa with the use of personal protective equipment and also to find out how these problems can be prevented or solved. A quantitative research study was done using a questionnaire as a data gathering tool on workers who are exposed to occupational injuries and illnesses and who use personal protective equipment for their protection. The findings revealed that even though workers were using personal protective equipment they still got occupational injuries and illnesses. They also had problems with their protective equipment like incompatible types of personal protective equipment, such as weight where heavy personal protective equipment like boots were issued and very hot or cold personal protective equipment incompatible with the temperature of the environment. Some personal protective equipment like gloves were of a wrong size and caused allergy. In some instances unavailability of or unsuitable personal protective equipment posed challenges to these workers. / Health Studies / M. A. (Health Studies)

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