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The relevance of qualifications offered at a selected Technical and Vocational Education and Training (TVET) college in MpumalangaSchnobel, Lucy Elizabeth Wanjugu 23 July 2020 (has links)
Considering that Mpumalanga province has a large petrochemical plant owned by a multinational company that runs and owns mines, the province should abound with employment opportunities for Technical and Vocational Education and Training (TVET) college graduates, especially those from the local Gert Sibande TVET College. However, students with TVET college qualifications struggle to attract employment. Therefore, this study explored the question, “What can TVET providers in Mpumalanga do to enhance students’ employability?” The research was conducted in a selected TVET college in the province. The study employed a qualitative approach and an interpretive paradigm. Data were collected using semi-structured interviews, focus groups and document analysis. The identities of all respondents were protected. Upon analysis of the results, several measures that the TVET college, stakeholders and employers could employ, emerged. There was a lack of proper skills for graduates, qualifications without relevance and employers hardly acknowledging the TVET college qualifications. Some of the recommendations made include collaboration, relationship building between stakeholders and revision of the National Certificate (Vocational) [NC-(V)] curriculum. Topics for future research are also suggested. / Educational Management and Leadership / M. Ed. (Education Management)
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Guidelines to apply the integrated housing needs system to allocate houses in the Mpumalanga province, South AfricaSigudla, Jerry 11 1900 (has links)
Mpumalanga Provincial Department of Human Settlements in partnership with the
National Department of Human Settlements has launched a new integrated system
known as the Housing Needs Register (HNR) to manage potential housing
beneficiaries. This study was aimed at refining the integrated system in terms of
providing guidelines and processes in the allocation of affordable houses.
A total of 88 878 records captured on the HNR were profiled, and the results show that
in approximately 86% of the records, family factors and better economic circumstances
were given as the main motivation towards a desire to own a house in a particular area
of residence. These findings emphasized the importance of understanding
beneficiaries’ needs with regard to housing. Providing guidelines in the application of
this knowledge in a fair and consistent manner could assist in curtailing the spread of
informal selling or demolishing of state subsidized houses and other forms of corruption. / Public Health / M.A. (Public Health)
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External whole school evaluation of underperforming secondary schools in Mpumalanga provinceMathaba, Richard Siphamandla Ryan 13 June 2014 (has links)
Submitted in fulfilment of part of the requirements for the Degree of Doctor of Technology,
Durban University of Technology, 2014. / The study is based in the Mpumalanga Province and focused on a sample of 18 externally evaluated underperforming secondary schools across all four districts of the province. The schools obtained less than 30% average pass rate of learners in the 2011 Grade 12 examinations. The main objectives of the study were to analyse the purpose of Whole School Evaluation (WSE) from a quality assurance perspective, investigate the significance of a key component of WSE, namely, teaching, learning and educator development, analyse the Grade 12 results of externally evaluated underperforming secondary schools prior and post evaluation, analyse monitoring and evaluation reports for changes in teaching, learning and teacher development, as well as identify factors impeding teaching, learning and teacher development in underperforming secondary schools.
The mixed methods approach was used. This approach made it easy to reconcile findings through triangulation and complementing qualitative and quantitative data (both primary and secondary).This study relied on secondary data (WSE external evaluation reports and Grade 12 results), as well as primary data obtained from questionnaires administered to school management teams (SMTs) of the sampled underperforming secondary schools.
The study exposed the great level of acceptance of the external WSE process by SMTs in Mpumalanga Province underperforming secondary schools, as a means of quality assurance towards improvement. Furthermore, it revealed the extent to which improvement and development of schools in the underperforming schools as a result of the external WSE process. The study also indicated that the results of seventeen of the eighteen schools (94.4%) improved. Furthermore, the study confirmed that what was revealed in the external WSE as areas for development became a revelation to SMTs. As a result, the manner in which teaching, learning and teacher development (AFE4) as a key component of WSE is viewed by teachers and SMTs, has been positively influenced.
The study produced new knowledge through the development of a theoretical model. This model is based on the view that effective external WSE process, as a dependent variable, is significantly influenced by predictor (independent) variables. The predictor (independent) variables are planning for teaching; teaching strategies; assessment of learners; teacher development; and management of teaching and learning processes (curriculum management). This emerging theoretical model is based on the belief that, the more one increases independent variables (they can be from any of the nine AFEs’ criteria), the more the dependent variable (effectiveness of external WSE process) is strengthened. / D
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Morphology, mineralogy and surface chemistry of manganiferous oxisols near Graskop, Mpumalanga Province, South AfricaDowding, Catherine Elaine 12 1900 (has links)
Thesis (MScAgric)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: In the humid Graskop region of Mpumalanga Province, South Africa, there is an
anomalous body of highly weathered black, manganiferous oxisols derived from dolomite.
With Mn contents as high as 17%, potential large-scale Mn release is an environmental
concern under current, acid generating, forestry practices. This study aims at establishing
the factors which may affect the stability of the manganiferous oxisols of Graskop and in
the process, investigating some of the morphological, mineralogical and chemical
properties of these unique soils.
Typically, the soils show a reddish, nodule-rich horizon, containing 3-4% Mn, grading
through a red and black mottled zone into a black (5YR 2.5/1) apedal subsoil with >7%
Mn. The Mn gradient down the profile as well as the abundant nodule content of the upper
subsoil horizons implies that Mn mobilization and redistribution are active pedogenic
processes. The exceptional Mn content of these soils is complemented with Fe and Al
concentrations of up to 10 and 8%, respectively, and anomalously high trace element levels
in particular Ni and Zn (as high as 541 and 237 mg kg-1, respectively) which are at the
upper limit of cited world natural maxima for soils. The Mn mineral lithiophorite
[(Al,Li)MnO2(OH)2], dominates the mineralogy of the soils with accessory amounts of
birnessite, gibbsite, goethite, hematite, maghemite, kaolinite, aluminous chlorite and mica -
a mineral suite reflecting that of well weathered soils.
With the pH of the soil being at or close to the point of zero charge (4.5-5.5) the soils show
isoelectric equilibrium. The very low buffer capacity results in metal dissolution
commencing with the first increment of titrated acidity. Manganese dissolution is relatively
minor considering the large potential for release and is highly overshadowed by Al release.
The apparent resilience of the Mn phase to added acidity may relate to the overwhelming
poise of the soils which maintains robust, oxic conditions despite the usual instability of
Mn oxides at low pH.
Manganese release and soil redox properties are substantially affected by drying especially
in the organic rich topsoils. Using various redox analyses, evidence is shown for
involvement of Mn(III)-organic complexes in the drying reactions. Using this and
information gained in a real time, attenuated total reflectance Fourier transform infrared(ATR-FTIR) spectroscopic study, a mechanism is suggested which may account for the
observed Mn release and the loss of Cr oxidising capacity commonly observed in dried
soils. The information provided by the ATR-FTIR study showed the decrease in surface
pH of a clay film, from 5 to below 2, as well as the shift in coordination nature of sorbed
oxalate from a more outer-sphere association to a more inner-sphere association
concomitant with the removal of free water from the clay surface. This spectroscopic
evidence for these chemical changes which accompany surface drying not only provides
further insight into the reactions involving Mn oxides in soils but also highlights the
suitability of ATR-FTIR for real time, in situ investigation into the chemistry of the drying
water interface.
From these results it is concluded that Mn release from the manganiferous oxisols, under
acid generation of the kind known to occur in pine plantations, is less that anticipated. On
the other hand, desiccation of the topsoil results in substantial Mn release with a suggested
mechanism which involves a Mn(III) intermediate. / AFRIKAANSE OPSOMMING: ‘n Onreelmatige grondliggaam van hoogs verweerde, swart, mangaanhoudende oxisols
wat uit dolomiet ontwikkel het, word in die humiede Graskop streek van die Mpumalanga
Provinsie van Suid-Afrika aangetref. Die hoë Mn-inhoud (tot 17%) van hierdie oxisols is
van groot omgewings-belang weens die potensiële grootskaalse Mn-vrystelling onder
huidige, suur-genererende bosbou praktyke. Hierdie studie beoog om die faktore wat die
stabiliteit van die mangaanhoudende oxisols van Graskop affekteer, vas te stel. Tesame
hiermee word die morfologiese, mineralogiese en chemiese eienskappe van hierdie
unieke gronde ondersoek.
Kenmerkend van hierdie gronde is ‘n rooi, nodule-ryke horison met 3-4% Mn aan die
oppervlakte. Bogenoemde horison verander met toename in diepte in ‘n rooi en swart
gevlekte sone wat weer in ‘n swart (5YR 2.5/1) apedale ondergrond met >7% Mn
oorgaan. Die Mn gradiënt in die profiel sowel as die hoë nodule-inhoud van die boonste
grondhorison dui daarop dat Mn-mobilisasie en -herverspreiding huidige aktiewe
pedogenetiese prosesse in die profiele is. Fe en Al, met konsentrasies van 10% en 8%
onderskeidelik, word saam met die onreelmatig hoë Mn inhoud aangetref. Baie hoë
vlakke van Ni en Zn (so hoog as 541 en 237 mg.kg-1 onderskeidelik) wat hoër is as
aangehaalde wêreld natuurlike maksimum waardes, word ook aangetref. Die mineralogie
van die gronde word deur die Mn mineraal litioforiet [(Al,Li)MnO2(OH)2] gedomineer.
Bykomstige hoeveelhede van birnessiet, gibbsiet, goethiet, hematiet, maghemiet,
kaoliniet, aluminiumryke chloried en mika word ook aangetref. Hierdie minerale
samestelling is kenmerkend van hoogs verweerde gronde.
Met die pH van die grond in die omgewing van die punt van geen lading (4.5 – 5.5),
word ‘n iso-elektriese ekwilibrium by die gronde aangetref. Die baie lae bufferkapasiteit
het metaal-oplossing aangehelp wat met die eerste inkrement van titreerbare suurheid ‘n
aanvang geneem het. Mangaan-oplossing is baie klein indien die groot potensiaal vir
vrystelling asook die groot mate van Al-vrystelling in ag geneem word. Die skynbare
teenwerking van die Mn fase tot toegevoegde suurheid, mag toegeskryf word aan diesterk ewewig van die gronde om sterk, oksiese kondisies, ten spyte van die normale
onstabiliteit van Mn oksiedes by lae pH, te onderhou.
Mangaan vrystelling en grond redoks eienskappe word beduidend deur uitdroging
beïnvloed en veral in die organies-ryke bogronde. Deur van verskeie redoks analises
gebruik te maak is daar bewyse van die betrokkenheid van Mn(III)-organiese komplekse
in die uitdroging-reaksies gevind. Dit. en data ingesamel in ‘n “real time, attenuated total
reflectance Fourier transform infrared (ATR-FTIR)” spektroskopiese studie, is gebruik
om ‘n meganisme voor te stel wat die waargenome Mn vrystelling en die verlies aan Cr
oksidasie kapasiteit (algemeen waargeneem in droë gronde) te kan verklaar. Die data
verkry met die ATR-FTIR studie het ‘n afname in oppervlak pH van 5 na 2 van ‘n klei
film asook die verskuiwing in koördinasie toestand van die gesorbeerde oksalaat van ‘n
meer buite-sfeer assosiasie tot ‘n meer binne-sfeer assosiasie, gepaardgaande met die
verwydering van vry water van die klei oppervlaktes, uitgewys. Die spektroskopiese
bewyse vir die chemiese veranderinge wat die oppervlak uitdroging vergesel, gee nie net
meer insig in die reaksies rakende Mn oksiedes in gronde nie maar onderstreep ook die
toepasbaarheid van die ATR-FTIR vir intydse (“real time”), in situ ondersoeke na die
chemie van die uitdrogende water kontakvlak.
Vanuit hierdie resultate kan afgelei word dat Mn vrystelling vanuit mangaanhoudende
oxisols onder suur genererende denne plantasies laer is as wat verwag is. Aan die ander
kant sal uitdroging van die bogrond tot aansienlike Mn vrystelling, met ‘n verwagte
meganisme wat Mn (III) as intermediêre toestand insluit, lei.
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The tectono-metamorphic evolution of the Theespruit Formation in the Tjakastad Schist Belt and surrounding areas of the Barberton Greenstone Belt, South AfricaDiener, Johann F. A. 12 1900 (has links)
Thesis (MSc)--University of Stellenbosch, 2004. / ENGLISH ABSTRACT: The southern portions of the Early- to Mid-Archaean Barberton granitoid-greenstone
terrain of South Africa consists of a high-grade metamorphic granitoid-gneiss terrain that
is juxtaposed against the low-grade metamorphic supracrustal sequence of the Barberton
Greenstone Belt. The boundary of the two different crustal domains corresponds to the
Theespruit Formation, an amphibolite-facies, highly tectonized mélange of metabasites,
felsic volcanics and rare, aluminous clastic sediments that occurs along the granitoidgreenstone
margins. Amphibolite-facies lithologies in the Theespruit Formation are
characterized by strongly prolate mylonitic fabrics that formed in a constrictional tectonic
regime. Away from the granitoid-greenstone margin and towards the central parts of the
greenstone belt, these rocks grade to, and are overprinted by, greenschist-facies S-L
mylonites that formed during non-coaxial deformation. Both peak and retrograde
minerals define, and are aligned parallel to, the fabrics in these rocks, indicating that
shearing was initiated under peak metamorphic conditions and continued during
retrogression. S-C’ fabric relationships indicate that shearing occurred in an extensional
tectonic regime and that, during deformation, the gneiss terrain was uplifted relative to
the greenstone belt. Peak metamorphic assemblages of grt-st-bt-chl-pl-qtz and ky-st-btms-
pl-qtz in metasediments and grt-ep-hbl-pl-qtz in amphibolite constrain peak
metamorphic conditions of 7.4 ± 1.0 kbar and 560 ± 20 ºC that were attained during the
main accretionary episode in the Barberton terrain at 3229 ± 25 Ma. Peak assemblages in
all rocks are pre-tectonic and were deformed and re-equilibrated during retrogression,
resulting in these being minimum estimates of peak metamorphic conditions.
Petrographic evidence and retrograde pressure-temperature estimates indicate that
retrogression involved near-isothermal decompression of ca. 4 kbar prior to cooling into
the greenschist-facies. The style and timing of metamorphism in the Theespruit
Formation is similar to that of the granitoid-gneiss terrain, suggesting that the Theespruit
Formation shares a geological history with the gneiss terrain and that it is allochtonous to
the greenstone belt. The main deformational and fabric-forming event exhibited in the
Theespruit Formation occurred during the exhumation of the granitoid-gneiss terrain
subsequent to peak metamorphism. Consequently, the juxtaposition of this terrain againstthe greenstone belt was achieved by tectonic underplating and core complex formation at
ca. 3.23 Ga. The occurrence of high-grade constrictional mylonites that are overprinted
by low-grade non-coaxial mylonites as well as extension in an overall compressional
tectonic regime is consistent with exhumation by extensional orogenic collapse. Burial
of the high-grade terrain to depths of 25 – 30 km is only possible in a relatively cold and
rigid crustal environment, while the extremely low apparent geothermal gradients of ca.
20 ºC/km preserved in this terrain suggest that burial and exhumation occurred rapidly,
within a time-span of ca. 15 – 20 Ma. These parameters strongly suggest that
metamorphism occurred in response to a lateral plate tectonic process that was
operational in the Barberton terrain at 3230 Ma. / AFRIKAANSE OPSOMMING: Die suidelike dele van die Vroeg- tot Middel-Argaïese Barberton graniet-groensteen
terrein van Suid-Afrika bestaan uit ‘n hoë-graad metamorfe graniet-gneiss terrein wat die
lae-graad metamorfe groenstene van die Barberton Groensteen Gordel begrens. Die
grens tussen die twee verskillende kors-domeine hang saam met die Theespruit Formasie,
‘n amfiboliet-fasies, getektoniseerde melange van metabasiete, felsiese vulkaniese
gesteentes en skaars, alumineuse klastiese sedimente wat langs die graniet-groensteen
kontakte voorkom. Amfiboliet-fasies gesteentes in die Theespruit Formasie word
gekenmerk deur sterk prolaat milonitiese maaksels wat in ‘n vernouende tektoniese
omgewing gevorm het. Hierdie rotse word weg van die graniet-groensteen kontak en na
die sentrale dele van die groensteen gordel oordruk en vervang deur groenskis-fasies S-L
miloniete wat tydens nie-koaksiale vervorming gevorm het. Beide piek en retrograad
minerale definieer, en is georienteer parallel aan, die maaksel in die rotse, wat daarop dui
dat skuifskeur onder piek metamorfe toestande begin het en volgehou het tydens
retrogressie. S-C’ maaksels dui daarop dat skuifskeur in ‘n verlengende tektoniese
omgewing plaasgevind het en dat die gneiss terrein opgehef is relatief tot die
groensteengordel tydens vervorming. Piek metamorfe versamelings van grt-st-bt-chl-plqtz
en ky-st-bt-ms-pl-qtz in metasedimente en grt-ep-hbl-pl-qtz in amfiboliet bepaal piek
metamorfe toestande van 7.4 ± 1.0 kbar en 560 ± 20 ºC wat bereik is gedurende die
hooffase van akkresie in die Barberton terrein teen 3229 ± 25 Ma. Die piek metamorfe
versamelings in alle rotse is pre-tektonies en is vervorm en geherekwilibreer tydens
retrogressie, wat maak dat die beramings minimum skattings van piek metamorfe
toestande is. Petrografiese getuienis asook druk-temperatuur beramings dui daarop dat
retrogressie gepaard gegaan het met byna-isotermiese drukverligting van naastenby 4
kbar voor afkoeling tot in die groenskis-fasies. Die styl en tydsberekening van
metamorfose in die Theespruit Formasie is vergelykbaar met metamorfose in die granietgneiss
terrein, wat daarop dui dat die Theespruit Formasie ‘n geologiese geskiedenis met
die gneiss terrein deel en allochtoon is tot die groensteen gordel. Die hooffase van
vervorming en maakselvorming in die Theespruit Formasie het plaasgevind gedurende
die herontbloting van die graniet-gneiss terrein na piek metamorfose. Gevolglik is dieteenplasing van dié terrein teen die groensteen gordel vermag deur tektoniese
onderplasing en kernkompleksvorming teen ongeveer 3.23 Ga. Die verskynsel van hoëgraadse
vernoude miloniete wat oordruk word deur lae-graadse nie-koaksiale miloniete
asook verlenging in ‘n algeheel saamdrukkende tektoniese omgewing dui daarop dat
herontbloting plaasgevind het deur middel van verlengende orogenetiese ineenstorting.
Die begrawing van die hoë-graadse terrein tot dieptes van 25 – 30 km is net moontlik in
‘n relatief koel en star kors-omgewing, terwyl die uitermate lae geotermiese gradiente
van ongeveer 20 ºC/km wat in die terrein behoue gebly het daarop dui dat begrawing en
herontbloting vinnig geskeid het, binne ‘n tydsverloop van ongeveer 15 – 20 Ma. Hierdie
beperkings is ‘n sterk aanduiding dat metamorfose plaasgevind het as gevolg van ‘n
laterale plaattektoniese proses wat werksaam was in die Barberton terrein teen 3230 Ma.
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Geochemical and stable isotope studies of gold bearing granitoids in the Murchison Schist Belt, North Eastern TransvaalKedda, Sean Waugh 23 January 2012 (has links)
M.Sc., Faculty of Science, University of the Witwatersrand, 1992
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The impact of cash loans (Mashonisas) on the welfare of the non-propertied : a case study on Tubatse Ferrochrome mineworkers in the Mpumalanga ProvinceMatabane, Mokgohloe Lorraine January 1999 (has links)
Thesis (M. Dev.) -- University of Limpopo, 1999 / Refer to document
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The effectiveness of the induction and orientation programme in the Nkangala Health District of Mpumalanga Province, 2006 to 2007.Kunene, Makazi Pearl. January 2010 (has links)
INTRODUCTION
The high staff turnover and high rates of absenteeism in health professionals poses an
alarming challenge in the Public Health Facilities in the Nkangala Health District of
Mpumalanga province. This could lead to the quality of care to patients being compromised.
The Human Resource Directorate within the Department of Health has introduced a formal
induction and orientation process in the health facilities for new staff which should assist with
the retention of staff and enhance their productivity.
PURPOSE OF THE STUDY
The purpose of this research study was to evaluate the effectiveness of the Human Resource
Management unit in implementing the induction and orientation programme for newly
appointed health professionals at the Nkangala Health District of Mpumalanga Province.
METHODS
The study method is quantitative in nature using an observational descriptive design with the
minor qualitative component for detailing the quantitative findings. Stratified random
sampling was used to select the respondents from the Persal database of 2006-2007. Two
hundred and three respondents participated in this study. The Persal database is the human
resource database used for managing the personnel records of all permanent employees. A
self-administered questionnaire was developed to collect data from the health care
professionals at the Thembisile and JS Moroka health facilities in the Nkangala Health
District in Mpumalanga. The exposure variable was the implementation of the induction and
orientation programme. The outcome variable was the measurement of the effective
implementation of the induction and orientation programme. The questionnaire consisted of
open- and closed-ended questions covering demographic data and organisational
characteristics related to the objectives of the study.
The validation of the questionnaire was done in consultation with the Human Resource
Development unit of the Nkangala Health District through a pilot study. The data was
collected using Microsoft Excel and analysed using SPSS statistical software.
RESULTS
The data was categorised and interpreted according to the respondents’ views. The findings
were presented using categorical variables of medical doctors, allied health professionals,
nursing staff and health facility managers. The site questionnaire was based on the
Departmental Transformation Unit tool to assess the 6 variables being purpose,
empowerment, relationships and communications, flexibility, optimal productivity,
recognition and morale relating to the performance of health facilities. MS Excel was used to
consolidate the views of the respondents in relation to the implementation of induction and
orientation programme which did not benefit the medical doctors and allied health
professionals as they were not assigned with mentors.
DISCUSSION
This study identified the most important interventions and support that newly employed
health professionals expected in their career development. The induction and orientation
programmes are used interchangeably by the Human Resource Department - hence, there was
no formal induction process conducted. The induction and orientation process is not being
evaluated to review the programme. The facility managers’ participation in the study assisted
with their supportive roles in the career development of the health professionals.
CONCLUSION
It is hoped that the findings of this study will be of benefit to the Health Professionals in the
Department of Health, Mpumalanga Province, South Africa. In addition, the study assessed
the Management of Career Development programme which is used by the Department of
Health in Mpumalanga Province to strengthen the induction and orientation programme of
health professionals. / Thesis (M.Med.)-University of KwaZulu-Natal, Durban, 2010.
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Monitoring ground-level ozone and nitrogen dioxide in parts of KwaZulu-Natal and Mpumalanga (South Africa) by means of chemical and biological techniques.Blair, Sharon Ann. January 1998 (has links)
Surface ozone (O3) is one of the most toxic and abundant air pollutants. It has deleterious effects on human and animal respiration processes, and adversely affects plants. Four sites were selected for monitoring ambient O3 in the Durban metropolitan area: Botanic Gardens, University of Natal (UND), top of Kloof Gorge, and Mooi River. At each site tobacco Bel-W3 bioindicators, and NO2 and O3 passive diffusion tubes were placed. An O3 analyser (Dasibi 1108) was situated at the UND site. Monitoring was carried out for four weeks during summer, autumn and winter at each site, and during spring at the UND site. Two weeks of data from the diffusion tubes were collected during spring, from the Nelspruit area, Mpumalanga. Ozone concentrations measured with the Dasibi at the UND site were low in comparison to other urban-industrial areas in the world, with hourly values falling between 5ppb and 10 ppb. The highest hourly mean maximum recorded was 40ppb. A general spring/winter maximum and summer minimum was observed. This is typical of subtropical locations, where subsidence in prevailing anticyclonic circulation occurs. Diurnal characteristics included early morning minima and maxima at 12h00 in spring and summer, and maxima approximately two hours later in autumn and winter. This pattern was typical of that found in polluted environments, the magnitude, however, being lower. An unusual secondary nocturnal peak occurred during autumn, winter and spring. This could have been due to the long-range transport of relatively O3-rich air from a non-urban, high altitude inland area. Ozone concentrations were not strongly influenced by meteorological variables. Diffusion tube data indicated low O3, however, the coefficients of variation were high, implying a lack of precision in this technique. This technique would have to be improved before data obtained could be regarded as valid. Nitrogen dioxide, NO2, one of the precursors to O3, was monitored using diffusion tubes at the same sites. Concentrations were highest closer to the city centre, the highest concentration being 31ppb in autumn. In the Mpumalanga study, NO2 concentrations were higher in the city of Nelspruit than the surrounding areas. No significant differences were found in the O3 concentrations between the Mpumalanga sites. The tobacco plants showed the highest visible leaf injury in winter, corresponding with the higher Dasibi values, but there were no significant differences between the sites, and no significant differences in chlorophyll contents between the sites. In this study, O3-induced injury occurred below the previously established threshold of 40ppb. / Thesis (M.Sc.)-University of Natal, Durban, 1998.
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The physical volcanology and geochemistry of the Nsuze group, Pongola supergroup, of northern KwaZulu-Natal and southeastern Mpumalanga.Grant, Claire Elizabeth. January 2003 (has links)
The Nsuze Group forms the lower,
predominantly volcanic succession of the
Pongola Supergroup. The 2.9Ga Nsuze Group
outcrops in southeastern Mpumalanga, northern
KwaZulu-Natal and Swaziland. The volcanic
rocks of the Nsuze Group are basalts, basaltic
andesites, andesites, dacites and rhyolites
preserved as both lava and pyroclastic deposits.
The oldest volcanic sequence of the Nsuze Group
is the basaltic Wagondrift Formation. The
younger Bivane Subgroup represents the main
volcanic component of the Nsuze Group. The
White River Section represents a complex
volcanic history of magma storage, fractionation,
and eruption, supplied by a multi-level system of
magma chambers. The basaltic and basaltic
andesite rocks of the White Mfolozi Inlier
represent the steady and non-violent eruption of
lavas from related volcanic centres. The Nsuze
Group rocks have been metamorphosed by high
heat flow burial metamorphism to lower
greenschist facies. Geochemically, elements
display well-defined fractionation trends, with
evident sub-trends within each phase group of
samples. These sub-trends are related to the
fractionation of key minerals, in particular
plagioclase. The REE patterns show that
evolution of magma was largely controlled by
the fractionation of plagioclase. All REE
patterns show LREE enrichment relative to the
HREE. The Wagondrift Formation was derived
from a more depleted source than the younger
Bivane Subgroup volcanic rocks and exhibits a
within-plate tectonic signature. The volcanic
rocks of the Bivane Subgroup in the White River
Section and the White Mfolozi Inlier are
geochemically similar. The volcanic rocks of the
Bivane Subgroup of both the White River
Section and the White Mfolozi Inlier have a
subduction zone tectonic signature, in particular
a Ta-Nb negative anomaly. Tectonic
discrimination diagrams suggest an enriched
source related to a continental-arc setting. The
geochemistry suggests an eclogitic source for the
Nsuze Group volcanic rocks. The formation of
eclogite in the mantle requires subduction of
basaltic material. Archaean models for
subduction-like processes include decoupling of
oceanic crust and subsequent underplating of the
continental lithosphere, and low-angle
subduction which minimises the effect of the
mantle wedge. It is possible that a combination
of these processes resulted in an enriched
eclogitic source for the magmas of the Nsuze
Group. / Thesis (M.Sc.)-University of Natal, Durban, 2003.
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