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Elizabeth Castle forms part of the South-East Granite Complex of Jersey, Channel Islands and is one of several multi-magma complexes in the region. The rocks have calc-alkaline signatures indicative of a subduction zone setting. In the western half of the Elizabeth Castle complex, the outcrops are wholly granophyre, while to the east, granophyre and minor monzogranite are intimately associated with diorite. The dioritic rocks form part of a layered series which is preserved at several localities. The layered diorites were initially intruded by multiple sub-horizontal granitic sheets. All contacts between the diorite and the granitic sheets are crenulate, indicating that the two were present as coexisting magmas. Fine-grained, dark margins in the diorites contain quench textures such as spherulitic plagioclase and acicular apatite, and are interpreted as chilled margins. At many contacts a narrow tonalitic marginal zone, with acicular amphiboles, is present. Field relationships suggest that this is a hybrid produced by interaction between coexisting dioritic and granitic magmas and this is confirmed by modelling based on geochemical data. It is proposed that within the marginal zones the presence of volatile-rich fluids, increased temperatures and a decrease in viscosity promoted chemical diffusion across the dioritegranite interface. The transfer of elements, together with the presence of volatiles, promoted the growth of hydrous mafic phases and suppressed crystallization of alkali feldspar. At the same time, fluid infiltration modified the composition of the dioritic magma. Field evidence indicates that these processes took place in a narrow time frame prior to further granitic intrusion. Parts of the sheeted complex were extensively disrupted by the later granitic intrusions, producing large areas rich in dioritic enclaves. Within these disrupted areas a grey inhomogeneous rock is encountered. Field and petrographic evidence suggest that this is a hybrid rock produced by the physical mixing of dioritic and granitic magmas. Linear chemical trends confirm this interpretation. Minor intrusions comprising red granite dykes, basic dykes, composite dykes and aplite sheets cut the complex.

North Crater occupies the north-western quadrant of the Tongariro Volcanic Centre and represents one of at least eleven vents which have been active on Tongariro since the last glacial maximum. The most recent cone-forming activity at North Crater is thought to have occurred between 14-12 ka ago to produce the distinct, wide, flattopped andesite cone. This project focused mainly on the cone-building eruptions at North Crater, including stratigraphic correlations with distal tephra, interpreting eruptive processes, and establishing the sequence of events during cone construction. Detailed field work identified key stratigraphic sections and facies in the proximal, medial and distal environments. These sections allowed stratigraphic correlations to be made between proximal cone-building facies and distal sheet-forming facies at North Crater, and established a complete North Crater eruption stratigraphy. In the proximal environment, welded and non to poorly welded facies formed from fallout of a lava-fountain, pyroclastic flow or as fallout from a convecting plume. In the medial and distal environment, the lithofacies consist of fallout from a convecting plume and minor pyroclastic flow. Convective fall and non to poorly welded pyroclastic flow deposits dominate the lower eruption stratigraphy suggesting explosive eruptions involving a gas-rich magma. A change to welded deposits produced from lava-fountaining occurs later in the cone-building sequence and suggest a change to lower explosively and eruption of gas-poor magma. Grain size, componentry data, density, petrography and SEM analysis were carried out on representative samples to characterise the different facies, and reveal information about eruption processes. The non to poorly welded deposits are typically made up of vesicular pumice, scoria and mingled clasts of sub-rounded bombs and lapilli. The welded facies are relatively dense and clast outlines are often difficult to distinguish. The eruptives are porphyritic with abundant plagioclase gt clinopyroxene gt orthopyroxene gt opaques. Quartzofeldspathic crustal xenoliths are common and indicate crustal assimilation. Mingled clasts of light and dark glass were found to have microlites present in the dark glass, but were absent in the light glass. Electron microprobe analyses found that the dark and light glass components in a single clast had similar compositions, showing that the contrasting physical appearance of the glass is not due to a different chemical composition. Forty three whole rock XRF analyses showed that the magmas ranged from basaltic andesite to andesite, and Harker variation plots display linear trends typical of magma mixing. Magma mixing as the most important magmatic process is supported by disequilibrium of phenocryst compositions and phenocryst textures. Magma viscosity, bulk density and temperature was determined using MAGMA (Kware), and indicate that they fall into the range of typical andesites. Eruptive activity involved vigorous lava-fountaining, minor convecting eruption plumes and dominant collapsing eruption plumes. This activity has produced welded and non-welded pyroclastic flow and fall deposits to form the large cone seen today. There are significant volcanic hazards associated with this style of activity at North Crater, characterised by lava-fountaining, eruption plume fallout, and widespread pyroclastic flows and lahars extending beyond the ring plain. These could all be potentially devastating to the central North Island of New Zealand.

Field evidence from exposed plutonic rocks indicates that mafic-felsic magma interaction is an important process during the construction and evolution of magma chambers. The exhumed, ~140 Ma, Halfmoon Pluton of Stewart Island, New Zealand is characterized by a sequence of mingled mafic sheets and enclaves preserved within an intermediate-felsic host, and provides a unique opportunity to directly investigate the physico-chemical processes that operate within an arc setting. Interpretation of mingling structures and textures in the field, in combination with extensive petrographic, geochemical and geochronological data, allow for conclusions to be reached regarding the nature of the mafic-felsic magma interactions, and the physical, chemical and thermal processes responsible for the generation and evolution of the calc-alkaline magmas. Detailed documentation and interpretation of mafic-felsic magma mingling structures and textures reveal that the Halfmoon Pluton formed incrementally as the result of episodic replenishments of mafic magma emplaced onto the floor of an aggrading intermediate-felsic magma chamber. Physico-chemical processes identified include fractional crystallization and accumulation of a plagioclase – hornblende – apatite – zircon mineral assemblage, episodic replenishment by hot, wet basaltic magmas, magmatic flow and compaction. Early amphibole and apatite crystallization played an important role in the compositional diversity within the Halfmoon Pluton. Variations in the style of magma mingling preserved within the magmatic “stratigraphy” indicate that processes operating within the chamber varied in space and time. Variations in mineral zoning and composition within hornblende indicate that the Halfmoon Pluton crystallized within a magma in which melt composition fluctuated in response to repeated mafic magma replenishments, fractionation, crystal settling and convection. Mineral assemblages, chemical characteristics, isotopic data and geochronological evidence indicate that the amphibole-rich calc-alkaline Halfmoon Pluton was emplaced into a juvenile arc setting, most probably an island-arc. Data are consistent with a model whereby ‘wet’ amphibole-rich basaltic magmas pond at the crust-mantle interface and episodically rise, inject and mingle with an overlying intermediate-felsic magma chamber that itself represents the fractionated product of the mantle melts.

Syfte – Att skapa en ny produkt inom kategorin mingelbord, som erbjuder fler användningsområden för att bli mer anpassad för privatpersoner och i hemmamiljö. Att genom en innovativ konstruktion och en kombination av moduliserade- och hantverksdelar skapa en unik produkt på marknaden. Metod – Grundmetoden för det här arbetet är den första fasen i en produkts liv: produktutvecklingsprocessen; identifiera behovet, planera designprocessen, ta fram kundkraven, utveckla konceptet och till sist utveckla produkten. Resultat – Designkoncept på ett mingelbord har tagits fram och redovisas i bilder. Dessa bilder är resultatet av en uppmodellering i datorn med hjälp av 3D-progam. För att få en mer realistisk känsla för material och form har bilderna även renderats. Implikationer – Resultatet av denna studie visar att mingelbord, genom konstruktionsändringar, kan utöka dess användningsområde utan att förändra grundfunktionen. Med utveckling av det framlagda konceptet kan ytterligare användningsområden skapas.  Begränsningar – I denna rapport har fokus lagts på de skeden innan själva tillverkningen och resultatet innebär då inte färdigt produktionsunderlag. Nyckelord – Hemmamiljö, justerbar, hantverk, funktionalitet, produktutveckling, design, mingelbord. / Purpose – To come up with a new product within the category of mingling table that provides an expanded area of use. This to be better adapted to individuals and at a home environment. Through an innovative construction and a combination of modulated- and hand made parts is the purpose to create a unique product on the market. Method – The first part of the life of a product: the product development process; identify the need, plan the process of the design, identify the customer demands, develop the concept and finally develop the product.  Findings – A mingling table has been created and is presented in pictures. These pictures are computer aided visualized. By rending the images is a more realistic feeling given to the table. Implications – The results of this thesis shows that tables within the category of mingling tables, through changes in its construction, could broaden its field of use. Through further development of the presented concept additional areas of usage  may be achieved. Limitations – This thesis has its focus on the time before the actual manufacturing of the product. This project emphasizes the product development process only.   Keywords – Home environment, customizable , functionality, product development, design, mingling table.

Field evidence from exposed plutonic rocks indicates that mafic-felsic magma interaction is an important process during the construction and evolution of magma chambers. The exhumed, ~140 Ma, Halfmoon Pluton of Stewart Island, New Zealand is characterized by a sequence of mingled mafic sheets and enclaves preserved within an intermediate-felsic host, and provides a unique opportunity to directly investigate the physico-chemical processes that operate within an arc setting. Interpretation of mingling structures and textures in the field, in combination with extensive petrographic, geochemical and geochronological data, allow for conclusions to be reached regarding the nature of the mafic-felsic magma interactions, and the physical, chemical and thermal processes responsible for the generation and evolution of the calc-alkaline magmas. Detailed documentation and interpretation of mafic-felsic magma mingling structures and textures reveal that the Halfmoon Pluton formed incrementally as the result of episodic replenishments of mafic magma emplaced onto the floor of an aggrading intermediate-felsic magma chamber. Physico-chemical processes identified include fractional crystallization and accumulation of a plagioclase – hornblende – apatite – zircon mineral assemblage, episodic replenishment by hot, wet basaltic magmas, magmatic flow and compaction. Early amphibole and apatite crystallization played an important role in the compositional diversity within the Halfmoon Pluton. Variations in the style of magma mingling preserved within the magmatic “stratigraphy” indicate that processes operating within the chamber varied in space and time. Variations in mineral zoning and composition within hornblende indicate that the Halfmoon Pluton crystallized within a magma in which melt composition fluctuated in response to repeated mafic magma replenishments, fractionation, crystal settling and convection. Mineral assemblages, chemical characteristics, isotopic data and geochronological evidence indicate that the amphibole-rich calc-alkaline Halfmoon Pluton was emplaced into a juvenile arc setting, most probably an island-arc. Data are consistent with a model whereby ‘wet’ amphibole-rich basaltic magmas pond at the crust-mantle interface and episodically rise, inject and mingle with an overlying intermediate-felsic magma chamber that itself represents the fractionated product of the mantle melts.

The cellular operators (Vodacom, Cell C, MTN and now Virgin Mobile) market has over 39-million mobile phone subscribers and the fixed operator (Telkom) has almost 5 million subscribers [13]. Although the telecommunication sector has been experiencing this significant growth (in terms of numbers), monopolisation of the local loop by Telkom has also resulted in communication prices that are not affordable to the majority of South Africans. The government of South Africa has identified cost of telecommunication services as one of the key initiatives that must be addressed to improve equal levels of access to ICT services in general. Local Loop Unbundling (or LLU for short) has been identified by the South African government as a tool that will minimise control that Telkom has over the copper cable connecting exchanges to customers whilst at the same time driving down the costs of Telecommunication in the country. Although some countries have successfully implemented local loop unbundling, some have not been so successful [3]. This dissertation proposes ICT Systems and processes South Africa needs to have in place to become one of the few success stories. The proposed model was validated against the different models adopted in countries like France, Portugal, United Kingdom and Austria. This dissertation develops a model for implementing local loop unbundling in the South African ICT sector. Local loop unbundling (in short LLU) has been successfully (and unsuccessfully) implemented in a number of countries around the world [3]. The model being proposed recommends best practices to be followed by all stakeholders to ensure successful deployment of local loop unbundling. The research takes a closer look at the South African ICT sector and makes recommendations on processes and systems that are necessary to ensure successful deployment of local loop unbundling in South Africa. The dissertation is written from the view of Telkom (The incumbent Operator), competitors (existing ones and new entrants) and the Regulator (ICASA) and focuses mainly on:  Technical Processes and Challenges that must be addressed  Regulatory Process and Challenges that must be addressed  Economic Challenges that must be addressed  Comparison to international ICT Markets and  Recommendations and Conclusions. The dissertation also covers the development of the Local loop unbundling model charter, Local Loop Management website and processes (Annexure A and B) developed (using HTML) used for the management of the unbundling process. Keywords: o Local loop o Caged Co-location / Thesis (M.Ing. (Development and Management Engineering)--North-West University, Potchefstroom Campus, 2009.

The cellular operators (Vodacom, Cell C, MTN and now Virgin Mobile) market has over 39-million mobile phone subscribers and the fixed operator (Telkom) has almost 5 million subscribers [13]. Although the telecommunication sector has been experiencing this significant growth (in terms of numbers), monopolisation of the local loop by Telkom has also resulted in communication prices that are not affordable to the majority of South Africans. The government of South Africa has identified cost of telecommunication services as one of the key initiatives that must be addressed to improve equal levels of access to ICT services in general. Local Loop Unbundling (or LLU for short) has been identified by the South African government as a tool that will minimise control that Telkom has over the copper cable connecting exchanges to customers whilst at the same time driving down the costs of Telecommunication in the country. Although some countries have successfully implemented local loop unbundling, some have not been so successful [3]. This dissertation proposes ICT Systems and processes South Africa needs to have in place to become one of the few success stories. The proposed model was validated against the different models adopted in countries like France, Portugal, United Kingdom and Austria. This dissertation develops a model for implementing local loop unbundling in the South African ICT sector. Local loop unbundling (in short LLU) has been successfully (and unsuccessfully) implemented in a number of countries around the world [3]. The model being proposed recommends best practices to be followed by all stakeholders to ensure successful deployment of local loop unbundling. The research takes a closer look at the South African ICT sector and makes recommendations on processes and systems that are necessary to ensure successful deployment of local loop unbundling in South Africa. The dissertation is written from the view of Telkom (The incumbent Operator), competitors (existing ones and new entrants) and the Regulator (ICASA) and focuses mainly on:  Technical Processes and Challenges that must be addressed  Regulatory Process and Challenges that must be addressed  Economic Challenges that must be addressed  Comparison to international ICT Markets and  Recommendations and Conclusions. The dissertation also covers the development of the Local loop unbundling model charter, Local Loop Management website and processes (Annexure A and B) developed (using HTML) used for the management of the unbundling process. Keywords: o Local loop o Caged Co-location / Thesis (M.Ing. (Development and Management Engineering)--North-West University, Potchefstroom Campus, 2009.

Samli Fe-oxide (+Cu&plusmn / Au) deposit is hosted by Samli pluton and rocks of Karakaya Complex in western Anatolia. The pluton consists of both mafic and felsic phases showing magma mixing textures. 40Ar/39Ar geochronology yielded an age range of 23.2&plusmn / 0.5 to 22.42&plusmn / 0.11 Ma for the Samli pluton, overlapping with 40Ar/39Ar age of 22.33&plusmn / 0.59 Ma and U-Pb age of 23.34&plusmn / 0.19 Ma from alterations. Sr-Nd isotope data are suggestive of a metasomatized subcontinental lithospheric mantle (SCLM) source for the magma. Alteration-mineralization pattern is defined by a series of overlapping halos characterized by sodic-calcic (plagioclase-pyroxene&plusmn / scapolite), calcic (garnet-pyroxene&plusmn / epidote), potassic (biotite+magnetite+chalcopyrite), hematite-limonite, and late stage (chalcedony-calcite+native Cu) alterations. Stable (&delta / 18O, &delta / 34S) and radiogenic (87Sr/86Sr,143Nd/144Nd) isotope compositions suggest a magmatic source for the fluids responsible for alteration-mineralization. Given the spatial-temporal association of alteration- mineralization with magmatic rocks, the hydrothermal system that controls mineralization in Samli appears to be linked with emplacement and cooling of Samli pluton. Samli Fe-oxide (+Cu&plusmn / Au) deposit has features characteristic for both skarn- and Iron-Oxide-Copper-Gold (IOCG) type deposits. The spatial and temporal association with a porphyritic intrusion, widespread calc-silicate assemblage, metal content (abundant Fe-oxide with high copper content) are similar to calcic Fe-Cu skarns, whereas low-Ti (&le / 0.05% TiO2) magnetite/hematite, low-S sulfides (chalcopyrite&gt / pyrite), high Cu (up to 6.78%) and moderate Au (up to 8.82 ppm) grades, local structural control in alteration-mineralization, and the derivation of the causative magma from a SCLM resembles the features pertinent to IOCG type mineralization. Therefore, Samli deposit is defined as a skarn type Fe-Cu mineralization with a potential for IOCG type deposit.

No description available.