A contribution to the petrology of kimberlites
- Authors: Kruger, Floris Johan
- Date: 1978 , 2013-10-17
- Subjects: Kimberlite -- Africa, Southern , Petrology , Igneous rocks -- Inclusions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5024 , http://hdl.handle.net/10962/d1006886 , Kimberlite -- Africa, Southern , Petrology , Igneous rocks -- Inclusions
- Description: The petrogenetic relationships of the different varieties of kimberlite in the De Beers Mine and Letseng-Ia-terai composite diatremes have been investigated using petrographic and chemical methods. Kimberlites in the Letseng-Ia-terai diatreme were found to be strongly contaminated by crustal material, mainly basalt. A method to correct for the effects of the contamination has been developed and applied to these kimberlites. Using the corrected data, the four kimberlite types in each group appear to be related to each other by crystal/liquid fractionation models. However the two groups cannot be related to each other. The De Beer Mine has two varieties of kimberlite, a monticellite apatite and calcite rich variety which intruded first, and a phlogopite rich type forming a discrete cylindrical body within the earlier kimberlite. These two kimberlites do not appear to be related by any of the fractionation models discussed. An examination of the data from this work and published sources, suggests that kimberlites are derived from below the low velocity zone by small degrees of partial melting involving garnet lherzolite with subordinate phlogopite and carbonate. Diamonds are probably incorporated as xenocrysts in the magma. Upward movement and emplacement of kimberlite appears to have been very rapid. The diatremes were probably eroded and shaped by gas, derived from the kimberlite magma, escaping to surface along weak zones in the earth's crust. Xenoliths of crustal material incorporated in the kimberlite on intrusion have also been studied and various features due to alteration by the magma are described, including the formation of natrolite and cebollite. The latter is a rare mineral that has not been described from kimberlite before. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 1978
- Authors: Kruger, Floris Johan
- Date: 1978 , 2013-10-17
- Subjects: Kimberlite -- Africa, Southern , Petrology , Igneous rocks -- Inclusions
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5024 , http://hdl.handle.net/10962/d1006886 , Kimberlite -- Africa, Southern , Petrology , Igneous rocks -- Inclusions
- Description: The petrogenetic relationships of the different varieties of kimberlite in the De Beers Mine and Letseng-Ia-terai composite diatremes have been investigated using petrographic and chemical methods. Kimberlites in the Letseng-Ia-terai diatreme were found to be strongly contaminated by crustal material, mainly basalt. A method to correct for the effects of the contamination has been developed and applied to these kimberlites. Using the corrected data, the four kimberlite types in each group appear to be related to each other by crystal/liquid fractionation models. However the two groups cannot be related to each other. The De Beer Mine has two varieties of kimberlite, a monticellite apatite and calcite rich variety which intruded first, and a phlogopite rich type forming a discrete cylindrical body within the earlier kimberlite. These two kimberlites do not appear to be related by any of the fractionation models discussed. An examination of the data from this work and published sources, suggests that kimberlites are derived from below the low velocity zone by small degrees of partial melting involving garnet lherzolite with subordinate phlogopite and carbonate. Diamonds are probably incorporated as xenocrysts in the magma. Upward movement and emplacement of kimberlite appears to have been very rapid. The diatremes were probably eroded and shaped by gas, derived from the kimberlite magma, escaping to surface along weak zones in the earth's crust. Xenoliths of crustal material incorporated in the kimberlite on intrusion have also been studied and various features due to alteration by the magma are described, including the formation of natrolite and cebollite. The latter is a rare mineral that has not been described from kimberlite before. , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 1978
The development of the political party system in the Ciskei
- Authors: Ka Tywakadi, Gordon Renton
- Date: 1978 , 2013-10-17
- Subjects: Political parties -- South Africa -- Ciskei , Elections -- South Africa -- Ciskei
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2853 , http://hdl.handle.net/10962/d1006868 , Political parties -- South Africa -- Ciskei , Elections -- South Africa -- Ciskei
- Description: (p. 1) The Ciskei homeland, which is a 'sub-state' of the Republic of South Africa, attained a semi-autonomous status as a result of the implementation of the Bantustan policy of the Government of the Republic of South Africa. This semi-autonomous status introduced a Westminster type of parliamentary system which in turn brought into being a political party system. The purpose of this thesis is to investigate, amongst other things, the roles played by these political parties:- i) What role would the political parties play in the struggle of the Ciskeians for equal political rights vis - a-vis white South Africa? ii) Whose interests would those political parties serve? iii) This semi-autonomous status has resulted in the juxtaposing of traditional and modern political institutions. The political institutions that have emerged, include inter alia, legislative assemblies and political parties. These modern political institutions have been superimposed on traditional political institutions. What effect(s) would the one have on the other? iv) Would the development of political parties lead to the establishment of a one, two or dominant party system? In order that the above questions may be answered, i) An attempt will be made to define a political system, illustrating the concept with examples taken from the Republic of South Africa political scene and at the same time, attention will be directed to the relationship between the Republic of South Africa and the Ciskei. ii) When investigating the political party and the political party system, the role played by the political parties and the political party system in the relationship between the Republic of South Africa and the Ciskei will be defined. , Ciskei (South Africa) -- Politics and government , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 1978
- Authors: Ka Tywakadi, Gordon Renton
- Date: 1978 , 2013-10-17
- Subjects: Political parties -- South Africa -- Ciskei , Elections -- South Africa -- Ciskei
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2853 , http://hdl.handle.net/10962/d1006868 , Political parties -- South Africa -- Ciskei , Elections -- South Africa -- Ciskei
- Description: (p. 1) The Ciskei homeland, which is a 'sub-state' of the Republic of South Africa, attained a semi-autonomous status as a result of the implementation of the Bantustan policy of the Government of the Republic of South Africa. This semi-autonomous status introduced a Westminster type of parliamentary system which in turn brought into being a political party system. The purpose of this thesis is to investigate, amongst other things, the roles played by these political parties:- i) What role would the political parties play in the struggle of the Ciskeians for equal political rights vis - a-vis white South Africa? ii) Whose interests would those political parties serve? iii) This semi-autonomous status has resulted in the juxtaposing of traditional and modern political institutions. The political institutions that have emerged, include inter alia, legislative assemblies and political parties. These modern political institutions have been superimposed on traditional political institutions. What effect(s) would the one have on the other? iv) Would the development of political parties lead to the establishment of a one, two or dominant party system? In order that the above questions may be answered, i) An attempt will be made to define a political system, illustrating the concept with examples taken from the Republic of South Africa political scene and at the same time, attention will be directed to the relationship between the Republic of South Africa and the Ciskei. ii) When investigating the political party and the political party system, the role played by the political parties and the political party system in the relationship between the Republic of South Africa and the Ciskei will be defined. , Ciskei (South Africa) -- Politics and government , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 1978
The geochemistry and petrology of Karroo basalts of the Barkly East area, north eastern Cape
- Authors: Pemberton, John
- Date: 1978 , 2013-10-17
- Subjects: Basalt -- South Africa -- Eastern Cape , Petrology -- South Africa -- Eastern Cape , Geochemistry -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5042 , http://hdl.handle.net/10962/d1007646 , Basalt -- South Africa -- Eastern Cape , Petrology -- South Africa -- Eastern Cape , Geochemistry -- South Africa -- Eastern Cape
- Description: Sixty one basalt samples from the Drakensberg Subgroup in the Barkly East area were analysed for major elements and fourteen trace elements viz. Sr, Rb, Zr, Y, Nb, Zn, Cu, Ni, Co, V, Cr, La, Ce and Nd . These data confirm the tholeiitic nature of the Drakensberg Subgroup. Geochemical differences in the major element compositions are small within the different units of the Drakensberg Subgroup. Small differences are also evident between these units. The trace element variation between the units and within the Lesotho Formation are more pronounced than the variation of the major elements. The Lesotho Formation samples show a minor vertical increase in value for the top half of the Naudes Nek section in Fe, Ti, P, Zr, Nb, Y, La, Ce and Nd . A decrease in value from the same position in Mg, Ni and Co was observed. These patterns of variation are interpreted as representing low-pressure fractionation of plagioclase, olivine and clinopyroxene. Differences between the units of the Drakensberg Subgroup are examined by using absolute trace element contents and interelement ratios. Ratios of incompatible elements differ for the different units leading to the suggestion that a heterogeneous mantle is the most likely explanation for these differences. A unique unit of flows designated the Omega Formation is examined. The basal massive unit displays an unusual pattern of variation with height which suggests an origin through two different differentiation mechanisms. The data from this thesis are compared with those of Cox and Hornung (1966) on the central Lesotho basalts, Bristow (1976) on the southern Lebombo basalts and Robey (1976) on the Karroo dolerites of the Eastern Cape. The geochemical comparison between the lavas of the Lesotho Formation in the Barkly East area, central Lesotho and the Karroo dolerites show no major differences. However the southern Lebombo basalts show an enrichment in Sr and depletion in Cr.
- Full Text:
- Date Issued: 1978
- Authors: Pemberton, John
- Date: 1978 , 2013-10-17
- Subjects: Basalt -- South Africa -- Eastern Cape , Petrology -- South Africa -- Eastern Cape , Geochemistry -- South Africa -- Eastern Cape
- Language: English
- Type: Thesis , Masters , MSc
- Identifier: vital:5042 , http://hdl.handle.net/10962/d1007646 , Basalt -- South Africa -- Eastern Cape , Petrology -- South Africa -- Eastern Cape , Geochemistry -- South Africa -- Eastern Cape
- Description: Sixty one basalt samples from the Drakensberg Subgroup in the Barkly East area were analysed for major elements and fourteen trace elements viz. Sr, Rb, Zr, Y, Nb, Zn, Cu, Ni, Co, V, Cr, La, Ce and Nd . These data confirm the tholeiitic nature of the Drakensberg Subgroup. Geochemical differences in the major element compositions are small within the different units of the Drakensberg Subgroup. Small differences are also evident between these units. The trace element variation between the units and within the Lesotho Formation are more pronounced than the variation of the major elements. The Lesotho Formation samples show a minor vertical increase in value for the top half of the Naudes Nek section in Fe, Ti, P, Zr, Nb, Y, La, Ce and Nd . A decrease in value from the same position in Mg, Ni and Co was observed. These patterns of variation are interpreted as representing low-pressure fractionation of plagioclase, olivine and clinopyroxene. Differences between the units of the Drakensberg Subgroup are examined by using absolute trace element contents and interelement ratios. Ratios of incompatible elements differ for the different units leading to the suggestion that a heterogeneous mantle is the most likely explanation for these differences. A unique unit of flows designated the Omega Formation is examined. The basal massive unit displays an unusual pattern of variation with height which suggests an origin through two different differentiation mechanisms. The data from this thesis are compared with those of Cox and Hornung (1966) on the central Lesotho basalts, Bristow (1976) on the southern Lebombo basalts and Robey (1976) on the Karroo dolerites of the Eastern Cape. The geochemical comparison between the lavas of the Lesotho Formation in the Barkly East area, central Lesotho and the Karroo dolerites show no major differences. However the southern Lebombo basalts show an enrichment in Sr and depletion in Cr.
- Full Text:
- Date Issued: 1978
The nature of a self
- Authors: Le Chat, Gavin John
- Date: 1978 , 2013-10-17
- Subjects: Self , Identity (Philosophical concept) , Dualism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2737 , http://hdl.handle.net/10962/d1006916 , Self , Identity (Philosophical concept) , Dualism
- Description: The purpose of this thesis is to demonstrate just what kind of entity a self or person is (p. 1). , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 1978
- Authors: Le Chat, Gavin John
- Date: 1978 , 2013-10-17
- Subjects: Self , Identity (Philosophical concept) , Dualism
- Language: English
- Type: Thesis , Masters , MA
- Identifier: vital:2737 , http://hdl.handle.net/10962/d1006916 , Self , Identity (Philosophical concept) , Dualism
- Description: The purpose of this thesis is to demonstrate just what kind of entity a self or person is (p. 1). , KMBT_363 , Adobe Acrobat 9.54 Paper Capture Plug-in
- Full Text:
- Date Issued: 1978
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