Early Jurassic dolerites of the Karoo Large Igneous Province ( KLIP): an analysis of their age and emplacement history from sea level to the Drakensberg Mountains in the Eastern Cape , South Africa Submitted
- Authors: Muedi, Thomas Tshifhiwa
- Date: 2019
- Subjects: Geological time , Geochemistry Geology -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/41908 , vital:36608
- Description: South Africa hosts one of the largest Large Igneous Provinces (LIPs that is likely linked to the early separation of East and West Gondwana. However, despite many studies, the relationship between dolerites and volcanic basalts of this LIP (also known as the Karoo Large Igneous Province or KLIP) remains unsolved, because of poorly linked age dates (timing), geochemistry and emplacement mechanisms. This problem is in part because different unreliable dating techniques with large margin of errors have been applied This study aims to address these issues by performing new geo chemical and high resolution geochronological analyses on a number of dolerites (sills and dykes), volcanic s also referred to in the literature as the Drakensberg flood basalts) and samples from drill cores and field outcrops. This project is focused on dolerites in the Eastern Cape Province and provides results from field mapping of dolerites (sills and dykes) from the sea level to an elevation of circa 1350 metres above sea level (MASL) and their link to the volcanic in the Eastern Cape Province. The dolerite dykes observed trends from metres to hundreds of kilometres and cut across volcanic, which have similar geochemistry. The intrusive dolerites collected from the field and from d rill core samples were likely emplaced by magma infiltration through pre-existing sub vertical brittle fractures and fissures and then emplaced horizontally as sills circa 183 Ma Detailed fracture mapping across host rock to the dolerite was carried out to test if they acted as possible pathways for magmatic emplacements. The dolerite dykes and fractures mapped in the host sedimentary rocks have a dominant NW direction, especially towards volcanic basalts. The project provides tests based on the geochemical relationships of the dolerites and basalts from sixty-six (66) cores and field outcrop samples. The results confirm that the chemical analyses from the volcanic basalts an d dolerites are closely related and reveal that most samples are Ocean Island Basalt OIB), but some also reveal subduction related processes. This is consistent with models that suggest subduction along south west Gondwana may have influenced plumemagmatism derived from the lower mantle that initiated break up of this supercontinent e.g de Wit and Stern 1981 Storey et al , 1992 ; Torsvik et al., 2006 and Burke et al., 2008)
- Full Text:
- Date Issued: 2019
- Authors: Muedi, Thomas Tshifhiwa
- Date: 2019
- Subjects: Geological time , Geochemistry Geology -- South Africa
- Language: English
- Type: Thesis , Doctoral , PhD
- Identifier: http://hdl.handle.net/10948/41908 , vital:36608
- Description: South Africa hosts one of the largest Large Igneous Provinces (LIPs that is likely linked to the early separation of East and West Gondwana. However, despite many studies, the relationship between dolerites and volcanic basalts of this LIP (also known as the Karoo Large Igneous Province or KLIP) remains unsolved, because of poorly linked age dates (timing), geochemistry and emplacement mechanisms. This problem is in part because different unreliable dating techniques with large margin of errors have been applied This study aims to address these issues by performing new geo chemical and high resolution geochronological analyses on a number of dolerites (sills and dykes), volcanic s also referred to in the literature as the Drakensberg flood basalts) and samples from drill cores and field outcrops. This project is focused on dolerites in the Eastern Cape Province and provides results from field mapping of dolerites (sills and dykes) from the sea level to an elevation of circa 1350 metres above sea level (MASL) and their link to the volcanic in the Eastern Cape Province. The dolerite dykes observed trends from metres to hundreds of kilometres and cut across volcanic, which have similar geochemistry. The intrusive dolerites collected from the field and from d rill core samples were likely emplaced by magma infiltration through pre-existing sub vertical brittle fractures and fissures and then emplaced horizontally as sills circa 183 Ma Detailed fracture mapping across host rock to the dolerite was carried out to test if they acted as possible pathways for magmatic emplacements. The dolerite dykes and fractures mapped in the host sedimentary rocks have a dominant NW direction, especially towards volcanic basalts. The project provides tests based on the geochemical relationships of the dolerites and basalts from sixty-six (66) cores and field outcrop samples. The results confirm that the chemical analyses from the volcanic basalts an d dolerites are closely related and reveal that most samples are Ocean Island Basalt OIB), but some also reveal subduction related processes. This is consistent with models that suggest subduction along south west Gondwana may have influenced plumemagmatism derived from the lower mantle that initiated break up of this supercontinent e.g de Wit and Stern 1981 Storey et al , 1992 ; Torsvik et al., 2006 and Burke et al., 2008)
- Full Text:
- Date Issued: 2019
Articulating the nature of clinical nurse specialist practice
- Authors: Bell, Janet Deanne
- Date: 2015
- Subjects: Nurse practitioners , Intensive care nursing
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10057 , http://hdl.handle.net/10948/d1018623
- Description: Critical care nursing is a clinical specialist nursing practice discipline. The critical care nurse provides a constant presence in the care of a critically ill patient. She/he creates a thread of continuity in care through the myriad of other health care professionals and activities that form part of a patient’s stay in the critical care environment (World Federation of Critical Care Nurses [WFCCN], 2007). During conversations with people who have had intimate experience of the critical care environment, they have offered anecdotes that describe their interaction with critical care nurses who they perceive to be different from and better than other critical care nurses they encountered. Despite having met common professional requirements to be registered as a clinical specialist nurse, these distinctive, unique abilities that seem to be influential in meeting the complex needs and expectations of critically ill patients, their significant others as well as nursing and medical colleagues, are not displayed by all critical care nurses. While students of accredited postgraduate nursing programmes are required to advance their nursing knowledge and skill competence, many students do not seem to develop other, perhaps more tacit, qualities that utilisers characterise in their anecdotes of ‘different and better’ nursing practice. The overarching research question guiding this study was how can ‘different and better’ critical care nursing practice as recognised by a utiliser be explained? The purpose of this study was to develop an understanding of the qualities that those people who use critical care nursing practice recognise as ‘different and better’ to the norm of nursing practice they encounter in this discipline. The participant sample included patients’ significant others, nursing colleagues and medical colleagues of critical care nurses, collectively identified as utilisers. The stated aim of this work was to construct a grounded theory to elucidate an understanding of the qualities that a utiliser of critical care nursing recognises as ‘different and better’ critical care nursing practice in order to enhance the teaching and learning encounters between nurse educators and postgraduate students in learning programmes aiming to develop clinical specialist nurses. The method processes of grounded theory are designed to reveal and confirm concepts from within the data as well as the connections between these concepts, supporting the researcher in crafting a substantive theory that is definitively grounded in the participants’ views and stories (Streubert & Carpenter, 2011: 123, 128-129). Two data collection tools were employed in this study, namely in-depth unstructured individual interviews and naïve sketch. Constant comparative analysis, memo-writing, theoretical sampling, theoretical sensitivity and theoretical saturation as fundamental methods of data generation in grounded theory were applied. The study unfolded through three broad parts, namely: Forming & shaping this grounded theory through exploration and co-creation; Assimilating & situating this grounded theory through understanding and enfolding; Reflecting on this grounded theory through contemplating and reconnecting. The outcome of the first part of the study was my initial proposition of a grounded theory co-created in the interactions between the participants and myself. This was then challenged, developed and assimilated through a focussed literature review through the second part of the study. Through these two parts of this study, an inductively derived explanation was formed and shaped to produce an assimilated and situated substantive grounded theory named Being at Ease. This grounded theory articulates how ‘better and different’ nursing is recognised from the point of view of those who use the nursing ability of critical care nurses through the core concern ‘being at ease’ and its four categories ‘knowing self’, ‘skilled being’, connecting with intention’ and’ anchoring’. The final part of this study unfolded in my reflections on what this grounded theory had revealed about nurses and elements of nursing practice that are important to a utiliser in recognising ‘different and better’ critical care nursing. I suggest that as nurses we need to develop a language that enables us to reveal with clarity these intangible and tacit elements recognised within the being and doing of ‘different and better’ nursing. I reflected on the pivotal space of influence a teacher has with a student, and on how the elements essential in being and doing ‘different and better’ nursing need to be evident in her/his own ways of being a teacher of nursing. Teaching and learning encounters may be enhanced through drawing what this theory has shown as necessary elements that shape ‘different and better’ nurses through the moments of influence a teacher has in each encounter with a student.
- Full Text:
- Date Issued: 2015
- Authors: Bell, Janet Deanne
- Date: 2015
- Subjects: Nurse practitioners , Intensive care nursing
- Language: English
- Type: Thesis , Doctoral , DPhil
- Identifier: vital:10057 , http://hdl.handle.net/10948/d1018623
- Description: Critical care nursing is a clinical specialist nursing practice discipline. The critical care nurse provides a constant presence in the care of a critically ill patient. She/he creates a thread of continuity in care through the myriad of other health care professionals and activities that form part of a patient’s stay in the critical care environment (World Federation of Critical Care Nurses [WFCCN], 2007). During conversations with people who have had intimate experience of the critical care environment, they have offered anecdotes that describe their interaction with critical care nurses who they perceive to be different from and better than other critical care nurses they encountered. Despite having met common professional requirements to be registered as a clinical specialist nurse, these distinctive, unique abilities that seem to be influential in meeting the complex needs and expectations of critically ill patients, their significant others as well as nursing and medical colleagues, are not displayed by all critical care nurses. While students of accredited postgraduate nursing programmes are required to advance their nursing knowledge and skill competence, many students do not seem to develop other, perhaps more tacit, qualities that utilisers characterise in their anecdotes of ‘different and better’ nursing practice. The overarching research question guiding this study was how can ‘different and better’ critical care nursing practice as recognised by a utiliser be explained? The purpose of this study was to develop an understanding of the qualities that those people who use critical care nursing practice recognise as ‘different and better’ to the norm of nursing practice they encounter in this discipline. The participant sample included patients’ significant others, nursing colleagues and medical colleagues of critical care nurses, collectively identified as utilisers. The stated aim of this work was to construct a grounded theory to elucidate an understanding of the qualities that a utiliser of critical care nursing recognises as ‘different and better’ critical care nursing practice in order to enhance the teaching and learning encounters between nurse educators and postgraduate students in learning programmes aiming to develop clinical specialist nurses. The method processes of grounded theory are designed to reveal and confirm concepts from within the data as well as the connections between these concepts, supporting the researcher in crafting a substantive theory that is definitively grounded in the participants’ views and stories (Streubert & Carpenter, 2011: 123, 128-129). Two data collection tools were employed in this study, namely in-depth unstructured individual interviews and naïve sketch. Constant comparative analysis, memo-writing, theoretical sampling, theoretical sensitivity and theoretical saturation as fundamental methods of data generation in grounded theory were applied. The study unfolded through three broad parts, namely: Forming & shaping this grounded theory through exploration and co-creation; Assimilating & situating this grounded theory through understanding and enfolding; Reflecting on this grounded theory through contemplating and reconnecting. The outcome of the first part of the study was my initial proposition of a grounded theory co-created in the interactions between the participants and myself. This was then challenged, developed and assimilated through a focussed literature review through the second part of the study. Through these two parts of this study, an inductively derived explanation was formed and shaped to produce an assimilated and situated substantive grounded theory named Being at Ease. This grounded theory articulates how ‘better and different’ nursing is recognised from the point of view of those who use the nursing ability of critical care nurses through the core concern ‘being at ease’ and its four categories ‘knowing self’, ‘skilled being’, connecting with intention’ and’ anchoring’. The final part of this study unfolded in my reflections on what this grounded theory had revealed about nurses and elements of nursing practice that are important to a utiliser in recognising ‘different and better’ critical care nursing. I suggest that as nurses we need to develop a language that enables us to reveal with clarity these intangible and tacit elements recognised within the being and doing of ‘different and better’ nursing. I reflected on the pivotal space of influence a teacher has with a student, and on how the elements essential in being and doing ‘different and better’ nursing need to be evident in her/his own ways of being a teacher of nursing. Teaching and learning encounters may be enhanced through drawing what this theory has shown as necessary elements that shape ‘different and better’ nurses through the moments of influence a teacher has in each encounter with a student.
- Full Text:
- Date Issued: 2015
- «
- ‹
- 1
- ›
- »