Potential postgraduate projects
If you are interested in one of the projects below, please contact the responsible supervisor to discuss the project further. Not all staff members are represented here with projects at all times. You should therefore also browse though the Department's Research page and academic staff page to contact other supervisors whose research sounds interesting to you.
Available MSc research project for 2020: X-ray
micro-computed tomography (μCT) approach to the characterization of gemstones
Project description: During the last three
decades, the disclosure of gemstone treatment, such as fracture filling to improve
clarity or heat treatment to enhance colour, has been a topic of controversy in
the gemstone industry. This is further driven by the lack of an accepted
classification code for coloured gemstones (any gemstone other than diamonds).
Fracture filling for example, has the ability to significantly increase the
value of essentially poor quality gems and is difficult to visually detect and
quantify without resorting to destructive and time consuming methods. When such
enhancing treatments are not disclosed it poses a threat to consumer confidence
of an industry valued at US$10–$15 billion. This project will investigate the
potential of X-ray micro computed tomography (micro-CT or μCT) as a routine and
non-destructive method to aid the detection and quantification of clarity
enhancement within gemstones as well as providing a fingerprint unique for
every gemstone. The project will be well suited to a student with interests in
(1) Shark Tooth Forensics: Biodiversity survey of Miocene sediment from North Carolina, USA
(2) Radiometric age dating and analysis of the Jehol Group, Liaoning Province, China; Implications for the rise and radiation of Pygostylia (Theropod, Dinosauria)
(3) U-Pb province and basin analysis of detrital zircons recovered from the Adamantina Formation, Bauru Basin, Brazil
 "Were the Wolkberg Group lavas, underlying basement sills and a coinciding Rykoppies feeder dyke swarm emplaced during the same igneous event?": This project uses field relationships, petrography and bulk rock geochemistry to compare and investigate links between what appears to be coeval igneous units (outcrop across the Limpopo-Mpumalanga Provincial border), emplaced during a major tectonic and stratigraphical shift from the highly volcanic Ventersdorp (predominantly erupted along a SW-NE trending rift) to the more clastic-dominated Transvaal Supergroup (predominantly deposited within an E-W trending basin).
(2) (How) do quartz porphyry dykes of the Cape Granite Suite correlate across the Cape St Martin peninsular? As most of you may recall from our 2021 igneous field skills course, quartz porphyry dykes outcrop on either side of that peninsular point and it is not entirely obvious to me how these correlate. Thus, building on Otto’s (1957) detailed mapping of the peninsular, this may be refined through further ultra-detailed field and drone mapping. A compilation of existing thin sections and geochemistry, may supplement your study. If nobody else is in the process of dating any of these dykes and depending on your skills and ambition, you may attempt to separate zircons from a sample and U-Pb date these. Field work will be initiated during your first project period, unless you wish to use your vacation on it too.
(3) The effects of the Colenzo Fault along the south coast of Cape Columbine. Another feature that you may also recall from our 2021 igneous field skills course, is that the Cape Peninsular is pervasively cut by mylonitic shears. The plan is to quantify this deformation through – again – detailed field and drone mapping. One outcome of such mapping could be to establish a correlation between the amount of apparent horizontal displacements along these shears and their widths, which could then be used to estimate the amount of displacement along the a very much wider shear zone across the peninsular point of Cape Columbine. Another aim of the mapping is to relate these shears to the Colenzo fault as potential secondary faults. Finally, you may compare this relatively late-stage strain to rare remnants of an earlier and more ductile-looking deformation, cut by younger granites. Field work will be initiated during your first project period, unless you wish to use your vacation on it too.
(4) In case mafic dyke samples from across southern-central Africa are available for study, a number of projects may be based on these. Typically, these projects entail (1) a compilation of field relationships based on field photos and Google Earth, (2) the processing (crushing and milling) of samples for bulk rock geochemistry, as well as (3) flat-bed scanning of cut surfaces for preliminary petrographical studies and selection of think sections. Once the geochemical data and thin sections become available, you are expected to study and present these, before combining, discussing and interpreting the field relationships, petrography and geochemistry of whatever dykes may have been sampled. Sample processing will be completed during your first project period.
You are also welcome to propose your own igneous research project, preferably supported by, e.g., a mining/exploration company or government survey, or use my co-supervision on a project that links to igneous processes.
Gary Stevens has a diverse range of honours projects available to students interested in igneous and/or metamorphic petrology. Almost any type of project is possible including field- and/or petrography-based, experimental, modelling, analytical etc.
Field projects are possible within the Cape Granite Suite and the Saldanian orogeny, within the Barberton greenstone belt and surrounding TTG gneisses, within the Ancient Gneiss Complex of Swaziland and within the Limpopo belt. Experimental petrology and phase equilibrium modelling projects are available on the mechanisms by which rocks undergo partial melting, kinetic controls on the reaction path of incongruent partial melting reactions, phase relations in magmas of various kinds as a function of P,T and volatile content, the reaction mechanisms by which crystals react to re-establish equilibrium after compositional or PT change in magmas.
In all cases a bursary to cover tuition costs and contribute to living costs is included in the project. Such projects will be awarded to students who are interested in continuing with an expanded version of the project as an MSc study and who have achieved good marks in the parts of the BSc course that are relevant to the study. If you are interested please contact Gary email@example.com to discuss possible projects
Pegmatite exploration methods
One space available as part of the team working on Geochemical and mineralogical insights into the formation of pegmatites at Steinkopf and Tantalite Valley: linkages between ore mineralisation and the bulk rock / mineral chemistry of host pegmatites. Specifically, the work of the honours candidate would be focused on analytical production and testing of one of the first bulk rock compositions of a pegmatite through novel methodology development.
Optical microscopy image processing
One space available developing computer assisted techniques for image processing of thin sections. This project will involve the collection of data and images for optimisation of mineral identification via the optical microscope. Student is required to have a basic knowledge of computer programming and aptitude with an optical microscope.
Crustal processes and phase equilibria
Development of open system modelling tools as part of the "Rcrust" project (https://tinyurl.com/rcrust). These projects are focused on developing tools involving phase equilibria modelling of the crust. Current subtopics include trace element partitioning and accessory phase saturation, peritectic entrainment during anatexis and fractional crystallisation. Projects will involve a combination of field work, analytical techniques and computer programming. Students are required to have a basic knowledge of computer programming; the project will take place mostly in R but time is available for language migration and learning.
• What's lost when a wetland dries up? Development of a conceptual hydrogeologic model of the Verlorenvlei wetlands.
• How much pesticides are in our Western Cape waters? Evaluating the severity of aquatic pesticide pollution in the Western Cape and its main drivers.
• Does water dowsing work? Using an evidence-based approach to investigate the merits of a pseudoscience.
• Are igneous dykes barriers or conduits for groundwater flow? Assessing farmlands of Northeast South Africa.
A number of funded projects are available in the general field of Biogeochemistry of Trace metals in the Southern Ocean. The projects require a strong interest in Chemistry and Analytical Chemistry as applied to biological processes in the oceans. Superior laboratory skills and careful, forward thinking personality is a must. Although, your performance in tests and exams is important, it is not the sole parameter to work on the research projects. Students who intend to go on to MSc are preferred.
- A suite of projects are available related to the distribution of a) nutrient-type trace metals in the Southern Ocean, such as Fe, Cd, Cu, Zn, Mn .. as well as b) trace metals derived from anthropogenic emissions, such as lead (Pb)
- Related to the above topic is a study on methylmercury in the Southern Ocean. This project is only available to students wishing to pursue at least into M.Sc. A strong interest in interdisciplinary and international work is requested for these projects as it is a collaborative work with Mediterranean Institute of Oceanography, Marseille, France.
- Another project is offered in 2017 related to improve understanding of the re-dissolution of trace metals (some toxic and some fertilising) from re-suspended surface sediments in the Benguela Upwelling system. Such re-suspension of surface sediment can happen naturally due to turbulences or artificially due to dredging, for instance.
- Furthermore, we seek students to support our study on southern hemisphere aerosols sources and trajectories, their general geochemistry and trace metal composition, and their dissolution kinetics, which leads to study their potential fertilisation and/or inhibitory effects after deposition. A student with an interest in atmospheric sciences is required for this project.
- Linked to project #1d is a study on aluminium (Al) distribution in the Southern Ocean as tracer of dust deposition
- A fourth current related topic is to support our study on algae community composition and adaptation, driving factors and the impact on biogeochemical cycles (including carbon and its impact on the global climate), and/or on marine sediment formation (siliceous ooze, vs. calcareous ooze, for instance). A strong interest in interdisciplinary work, including biological sciences, is requested for this project.
Projects can also be designed in the field of hydrogeochemistry and Mine related pollution issues if they align with student interest, particularly looking at chemical characterization of groundwater, mineral dissolution kinetics and/or transport.
Another field of studies relates to paleo-geochemistry and climate reconstructions and establishing or improving tools for paleo-reconstructions. We use organic molecules to reconstruct the climate of the past, understand natural variability to disentangle the current anthropogenic impact. This, in turn, helps to improve the projections of the future. Climate reconstructions in the marine realm (Benguela system) and in eastern South Africa (St. Lucia) are currently available.
We also seek support for our study on river pollution and the impact of rainfall events on Western Cape's river water quality. A study conducted in 2016-2018 has revealed interesting trends in the Eerste River and Lourens River and we will extend this study to other rivers of the Western Cape in 2019.
Students are also welcome to approach us should they have their own ideas of a project.