Magister Scientiae - MSc (Earth Science)

Permanent URI for this collectionhttps://hdl.handle.net/10566/20292

Browse

Now showing 1 - 9 of 9

Sedimentological re-interpretation of zone 3 (upper shallow marine) of selected wells, Bredasdorp Basin (offshore South Africa)
(University of the Western Cape, 2014) Magobiyane, Nqweneka Veronica; Opuwari, Mimonitu; Donker, Jan Van Bever
The Bredasdorp Basin is located on the southern continental margin, off the coast of South Africa. It is mostly filled by marine Aptian to Maastrichtian deposits, overlaying pre-existing Late Jurassic to Early Cretaceous fluvial and shallow marine synrift deposits. The basin is a southeastern trending rift basin, located between the Columbine-Agulhas and Infanta arches. Its basement is made up of slates of the Bokkeveld Group (Devonian) and or quartzites of the Table Mountain Group (Ordovician-Silurian). The study area extends from x-x field to Y-Y field and encompasses only four wells for this investigation; well A, B, C and D respectively. This study was done through the interpretation; integration and juxtaposing of the results from core analysis with wireline log analysis (gamma ray) using Petrel software to display and correlate the well logs. Through core analysis which is the main source of information for this study, seven facies were identified and interpreted for the entire study. These facies alternate throughout each well and between different wells, but they are not evident in all the cores. Throughout the study, well A has been used as a reference well, since it appears (according to the interpretations) to record all seven facies and has the thickest section of zone 3. This zone reflects more accommodation space than the other studied wells at the time of deposition. Facies analysis of cores and well log correlation provide evidence that the studied USM sandstones are compatible with a wave dominated estuary/island-bar lagoon system to shoreface of a wave dominated marine shelf. It has previously been demonstrated that on the northern shelf of the Bredasdorp Basin, the USM typically has an hour-glass gamma ray log signature as a result of long-term transgression and regression and this typical log shape was also identified in this study from well A .
Identifying compartmentalization of the E-M Field, Bredasdorp Basin (South Africa) using well logs and core data
(University of the Western Cape, 2014) Williams, Albany
The E-M Field is situated in the Bredasdorp Basin off the south coast of South Africa. Production is taken place from Zone 2 of the upper shallow marine, the upper shallow marine is divided into five Zones numbered I-5.An investigation was done on the area after it was discovered that the hydrocarbons produces did not balance the hydrocarbon amounts estimated initially. Four boreholes were used for core analysis i.e. BH A, B, C and D. Cores were logged and facies were described in order to establish the depositional environment, it was identified that the environment intersected in Zone 3 is an estuarine system It was discovered from core analysis that Zone 3 contains barriers caused by mudstones of lagoon facies and baffles of tidal flat facies that prohibits the vertical flow of hydrocarbons from Zone 3 into Zone 2 where production is taken place. From the resistivity and neutron-density logs it was identified that only one out of the four boreholes i.e. BH A contains hydrocarbons while the other boreholes shows water bearing reservoirs. Borehole BH A contains a mudstone barrier which divides the Zone into two reservoir units and is capped by tidal flat facies which separates sandstone connectivity between Zone 3 and Zone 2. Using Petrel software it was possible to display the geometry of the environment in 3D and to visualize the barrier, baffles and the two reservoir units. It was identified from the structural model that the area is consists of 5 blocks, these blocks are divided by faults. Borehole BH A is situated in block 1. It is recommended that fluid samples be taken within Zone 3 for the identification of fluid type, it is also recommended that exploration of block 3 should be considered as this block has possible reservoir sandstones above the GWC and
The Application of Geophysical Wireline Logs for Porosity and Permeability Characterisation of Coal Seams for Coal Bed Methane Evaluation: Waterberg Basin, South Africa
(University of the Western Cape, 2012) Nimuno , Achu Teumahji; Opuwari, Mimonitu; Van Bever Donker, Jan
The fracture porosity and permeability of the Beaufort Seam 1 (BSl) and Ecca coal seams of the Waterberg Basin have been comprehensively characterised with the aid of geophysical wire-line logs. The main aim of the thesis was to estimate the porosity and permeability of the coal seams using down-hole wire-line data; comparing results from injection falloff test to establish the validity of the technique as a fast an effective method. The study area is the largely under explored Karoo-aged, fault bounded Waterberg basin Located in the Limpopo Province of South Africa. The study employed mainly the density and dual lateral resistivity logging data (Las format) from eight wells (WTB45, WTB48, WTB56, WTB58, WTB62, WTB65, WTB70 and WTB72). Density logging data was used for coal identification and fracture porosity estimation while fracture permeability was estimated from dual lateralog resistivity data. Analysis of fracture porosity required coal cementation indices and fracture width as an input parameter. These were estimated with the aid of water pump out test data, coal quality and gas analysis data provided by Anglo Coal in addition to the above mention logs. The collection of sheet coal model was used to represent anisotropic coal reservoirs with non-uniform fracture system was used to represent these coals. The mathematical formulas used to estimate both fracture porosity and permeability took into account the above coal model. The theoretical formulas are a modification from both Darcy's equation and Archie's equations. The coal seams were encountered at depths ranging from 198m to 385m in the wells and were marked by low density and very high resistivity. From the estimated results the coal reservoirs are characterised by high cementation indices ranging from 0.82 to 2.42, very low fracture porosity and low fracture permeability. Estimated results show that coal reservoir fracture porosity ranged from 0.0002% to 0.33% for both BSl and Ecca seams. Estimated results also show that coal reservoir permeability ranged from 0.0045mD to 6.0SmD in the BSl formation and from 0.01 to 0.107mD in the Ecca. Results when compared with those of injection falloff test shows that the estimated permeability is slightly lower as expected since the model did not account for coal anisopropy. The fracture permeability was found to decrease with increase in vitrinite content, coal rank, coal burial depth and increases with increase in inertinite content. On a basinal scale the model estimated permeability was found to increase slightly from the east to the west of the basin. The porosity decreases with increase cementation index for deeper coal seams and increases with increase cementation index for shallower coal seams.
Geochemical evaluation of source rocks within the upper Ecca, main Karoo
(University of the Western Cape, 2012) Mowzer Zainab; Carey, P; Opuwari, M.; .van Bever Donker, J.
Early works completed by Bouma, Johnson, Catuneanu, Wickens and others have paved the way in gaining a better understanding of the Karoo complex, from a sedimentology perspective. Research in this area is becoming more readily available as the oil industry seeks to gain more knowledge in this area for exploration purposes. Understanding this area can help aid in offshore development that is not as readily accessible as the onshore sediments. Using new modern technologies as well as old geochemical techniques we can expand our knowledge on hydrocarbons within this onshore environment. The Karoo in South Africa is an area in which petroleum studies are being reviewed with particular interest, especially within the Tanqua and Laingsburg subbasins of the Karoo. The particular formations of interest comprises of the Laingsburg, Fort Brown, Kookfontein and Vischkuil of the Upper Ecca group, located within the Laingsburg subbasin as well as the Kookfontein formation found within the Tanqua subbasin. The present work dealt with interpreting and, distinguishing the different types of source rock lithologies, to identify the source rock zones and organic matter within the Laingsburg, Fort Brown, Kookfontein and Vischkuil formations. This was achieved by utilising different geochemical analyses (such as rock eval pyrolysis and TOC) and organic chemistry (XRD) to assess the maturity, mineralogy and the quality of the source rocks. Forty samples were sent for TOC analyses. Rock samples were taken at various localities in the Fort Brown, Vischkuil and Laingsburg Formations, within the Laingsburg subbasin, whereas, Kookfontein core samples were obtained from the Tanqua subbasin. Overall, ten samples were selected from the 40 samples that had undergone TOC analysis. Using XRD, the core and rock outcrop samples showed clay minerals predominantly of illite, montmorillonite and chlorite. The TOe and rock-eval S 1 and S2 values from the formations within this study were anomalously low. The HI vs. TOe contained Type 1 and Type 2 kerogen plots, but this did not correspond with the HI vs. 01 index, because the samples were heavily oxidised.
Enhancing environmental and water science education: the development and evaluation of multi-media coursework materials
(University of the Western Cape, 2025) Gavor, Emily Akua Agyan
This study responds to persistent challenges in South Africa’s water sector by addressing the need for innovative, accessible, and contextually relevant educational tools for training environmental and water science professionals. The research centered on the development and evaluation of a multimedia interactive e-book designed to enhance conceptual understanding, engagement, and inclusivity within university-level Environmental and Water Science education. The study had two objectives: (1) to develop multimedia coursework materials packaged as an interactive e-book, and (2) to evaluate their effectiveness as a teaching tool. The e-book integrated animations, narrated videos, AI-generated graphics, flow diagrams, field-based visuals, problem-solving tasks, and isiXhosa translations, creating a visually engaging and linguistically inclusive learning resource. Its design followed constructivist and Universal Design for Learning (UDL) principles, supporting diverse learning needs. Evaluation methods included pre- and post-tests for two cohorts, quantitative statistical analysis using SPSS, and thematic analysis of qualitative feedback. Findings showed significant improvements in students’ understanding, engagement, confidence, and ease of use. In 2024, 88% of students reported improved understanding, and 76% found the e-book engaging. In 2025, understanding increased further, with 95.8% reporting improvement, 75% reporting strong engagement, and 83.3% rating the e-book as user-friendly. Interactive multimedia features were particularly effective in clarifying complex content, with 76% (2024) and 79.2% (2025) indicating that videos, diagrams, and quizzes helped them grasp difficult environmental and water science concepts. Chi-square results from the 2025 post-test confirmed that positive perceptions of e-book quality, usability, engagement, and effectiveness were statistically significant (p < 0.05). Although only 12.5% reported benefit from the translations, their inclusion strengthened multilingual accessibility and supported ongoing higher education transformation. This research demonstrates the value of multimedia-rich and linguistically inclusive digital tools in improving academic performance, engagement, and conceptual clarity in environmental and water science education. Recommendations include expanding multilingual content, enhancing mobile compatibility, integrating e-book use with field-based learning, and training educators in multimedia design and digital pedagogies. Future studies should explore long-term knowledge retention, user experience design for accessibility, and comparative evaluations with traditional teaching methods.
Designing a virtual geological field trip based on geo-cognition principles
(University of the Western Cape, 2024) Maart Rudy B.
This thesis investigates the design of Virtual Field Trips (VFT) using geocognition principles for geology education. As traditional in-person field trips face logistical, financial and accessibility challenges, this study explores Virtual Field Trip as a complementary tool. The VFT were created using high-resolution photography and geocognitive frameworks to create overlays and info text to highlight important features the students should be aware of when exploring an outcrop. The effectiveness of the VFT's design was tested on two first-year cohorts at the University of the Western Cape. Through a pre- & post-assessment approach, the learning gained from the VFTs was analysized. The results showed that the concepts that the VFTs explicitly showed, showed significant learning gained and the concepts that were merely implied showed little learning gained. Reflective feedback from the students emphasize the visual detail and interactive elements enhanced their understanding, though they recognized the importance of multimedia enhancements and instructor-led engagement. While VFTs are not meant to replace in-person field trips, they do offer a valuable and versatile educational tool. This study recommends the continued use and development of VFTs within the geosciences
A structural analysis of the Ou Kaapse Weg fault zone, Cape Peninsula, South Africa
(University of the Western Cape, 2024) Arnold, Andy Antonio
This thesis presents a structural analysis of the Ou Kaapse Weg Fault Zone, situated within the Silvermine Nature Reserve, with a specific focus on its interactions with the Muizenberg Fault Zone. The study aimed to characterise the fault systems, document their structural complexities, and place them within the broader tectonic framework of the region. A combination of detailed field mapping, remote sensing techniques, lineament extraction, and kinematic analysis was employed to identify and interpret the fault and joint systems in the area. Results indicate that thefaults within the Ou Kaapse Weg Fault Zone, particularly the Silvermine, Waterfall, and Boyes-Drive Faults, as well as the Muizenberg Fault Zone are predominantly strike-slip in nature, with significant evidence of left- lateral (sinistral) movement. Additionally, four major joint sets were identified: joint set-1 (NW-SE), joint set-2 (NE-SW), joint set-3 (E-W), and joint set-4 (N-S), which are spatially associated with the dominant fault trends. The spatial distribution and density of joints were found to increase significantly near fault zones, forming well-defined damage zones. These areas of intense fracturing are characterised by both orthogonal and conjugate joints. The presence of displaced joints and joint step-overs further underscores the complex stress regime and kinematics of the area.
The geology, geochemistry, and geochronology of proterozoic gneisses in the Lüderitz area, southern Namibia: insights into the evolution of the NW Namaqua Metamorphic Province
(University of the Western Cape, 2025) Shifotoka, Gerhard Mekondjo Naatangwe
The basement rocks of the Lüderitz area, SW Namibia are dominated by migmatitic metavolcanic and intrusive gneisses that resemble those of the Paleoproterozoic Richtersveld Magmatic Arc (~1890 Ma; RMA; of the Namaqua Natal Metamorphic Province (NNMP)). Detailed geological mapping, geochemistry, isotopic and geochronological analysis was undertaken to establish a new, modern lithostratigraphy for the area and to determine whether the Lüderitz gneisses indeed form part of the RMA. The mafic, andesitic and dacitic metavolcanic gneisses (1876 ± 9 Ma) are grouped in the Albatrosskop Formation and occur as rafts within the coeval orthogneisses (1918-1855 Ma). Six main types of orthogneiss were mapped, namely: the Kolmanskop Migmatite, Adventure Bay metagabbro-metadiorite, the Radford Bay, Kowisberg and Albatross Bay granodiorite-granite gneisses and the Elizabeth Point leucogranite gneiss. The volcanic and plutonic rocks are overlain by the Dagger Rocks Group that yielded a youngest detrital grain age of 1731 ± 46 Ma. The supracrustal and plutonic rocks were strongly deformed and metamorphosed during the polyphase Mesoproterozoic Namaqua Orogeny.
The petrophysical analysis and evaluation of hydrocarbon potential of sandstone units in the Bredasdorp Central Basin
(University of the Western Cape, 2005-12-01) Olajide, Oluseyi; Carey, Paul F.
This research was aimed at employing the broad use of petrophysical analysis and reservoir modelling techniques to explore the petroleum resources in the sandstone units of deep marine play in the Bredasdorp Basin.

Browse

Recent Submissions