The Northern Limb of the Bushveld Complex, South Africa is host to the world’s largest resource of platinum-group elements (PGE), along with significant nickel, copper and cobalt in a complex magmatic sulfide ore deposit. All of these resources are linked with environmentally-friendly technologies and energy usages in the automotive industry, with the PGE being essential components in catalytic converters (including Pd which has more than tripled in price in the past five years), and Ni, Co and Cu critical metals in Electric Vehicle batteries. As such, the northern limb of the Bushveld is likely going to play a large part in the switch to cleaner automotive technology.
The major deposit in the Critical Zone of the northern Bushveld (commonly known as the ‘Platreef’) rests directly on variable basement of Archaean and Paleoproterozoic units at surface. Down dip, it overlies Bushveld Complex Lower Zone rocks; themselves prospective for base metal sulfide mineralisation. The stratigraphy, structure, mineralization styles and metal budgets of the Northern Limb of the Bushveld Complex show important differences to the other limbs of the complex. The underlying causes behind these differences are poorly understood and no geological model exists to investigate them on anything more than a local scale.
This PhD project aims to tackle questions surrounding the controls on the emplacement of the various magmatic units, which appear to have their own, variable metal budgets and thicknesses. This focusses on processes that occur prior to and during emplacement and are critical to understanding the genetic and exploration models. The project is in partnership with Anglo American, who have been mining the Platreef via surface methods since the 1990s, and now operate the world’s largest PGE surface mining operation at the Mogalakwena Mine. Whilst the near-surface resources are reasonably well characterised, the down dip potential and extension of resources is known, but has had no research work completed on it thus far. Therefore, this PhD provides the opportunity to work on one of the world’s greatest ore deposits, with resources critical for a greener future, and at a time when exploration and mining activities in the area are expanding.
Research questions 1. How did the pre-existing basement architecture and structure control the emplacement, thickness and grade of the northern limb magmas.
2. Which direction did the (potentially) sulphide-laden magmas move? Where is the feeder? Can we vector towards higher tenors and possibly more massive sulfide in feeder conduits?
3. Is the Lower Zone emplaced entirely before the Critical Zone, or is the Critical Zone a differentiated continuum/mixing zone of residual Lower Zone magma? Which Lower Zone bodies are sources of viable Ni-Co-Cu-sulfides?
4. Were the magmas emplaced with a pre-enriched cargo of base and precious metals, and if so, where did the key processes of sulfide saturation and metal enrichment happen?
5. Are Northern Limb magmas inherently more Pd and Au enriched than the rest of the Bushveld?
In order to tackle the research questions, a multi-disciplinary approach will be used whereby the PhD researcher will undertake fieldwork in South Africa and make use of an unrivalled collective resource of laboratory facilities at Leicester, Cardiff and CSM (Exeter).
Entry requirements Applicants are required to hold/or expect to obtain a UK Bachelor Degree 2:1 or better in a relevant subject or overseas equivalent.
Experience of economic geology, igneous petrology and/or structural geology would be a benefit.
The University of Leicester English language requirements apply where applicable. https://le.ac.uk/study/research-degrees/entry-reqs/eng-lang-reqs/ielts-60
Enquiries Project / Funding Enquiries: [Email Address Removed], [Email Address Removed]
Application enquiries to [Email Address Removed]
How to apply Please refer to https://le.ac.uk/study/research-degrees/funded-opportunities/geol-sgge-holwell-1
This project is entirely funded by Anglo American through the Northern Limb 4D (NL4D) consortium grant.
4 year funding includes: Home/EU fees, an annual stipend in line with the UKRI rate (currently £15,009 for 2019/20), and a Research Training and Support Grant of £8,000 over the course of the project.
Grobler, DF, Brits, JAN, Maier, WD and Crossingham, A., 2018, Litho- and chemostratigraphy of the Flatreef PGE deposit, northern Bushveld Complex. Mineralium Deposita 54, 3-28.
McDonald I, Holwell DA. 2011. Geology of the Northern Bushveld Complex and the Setting and Genesis of the Platreef Ni-Cu-PGE Deposit. Reviews in Economic Geology 17, 297-327.
Yudovskaya, M.A., Kinnaird, J.A., Grobler, D.F., Costin, G., Abramova, V.D., Dunnett, T., Barnes, S-J. 2017. Zonation of Merensky-Style Platinum-Group Element Mineralization in Turfspruit Thick Reef Facies (Northern Limb of the Bushveld Complex). Economic Geology, 112, 1333-1365