12TH Annual IMSG at Oribi Gorge, KwaZulu-Natal 2024

On January 22-24, DSI-NRF CIMERA academics and students traveled to KwaZulu-Natal to attend the Igneous & Metamorphic Studies conference at the Oribi Gorge in KwaZulu-Natal. The conference has yet to be held since COVID-19, and the geologists were happy to resume the IMSG conference again.

The conference was organized by the host committee, Tanja Reinhard (UKZN), Jurgan Reinhardt(UWC), Lauren Hoyer & Saumitra Misra(UKZN), and Steffen Buttner from Rhodes University. Thank you to the Geological Society of South Africa, DSI-NRF CIMERA, Rhodes University of Faculty of Science, University of KwaZulu-Natal, Geo Explore Store, and Luhlaze for the Generous Sponsorships contributed to making the conference a success.

The conference was hosted at the Lake Eland Game Reserve on Oribi flats in Port Shepstone, in KwaZulu-Natal. The conference was well attended by more than 60 participants and consisted of 50 oral presentations and over 12 posters throughout the conference. It also included a half-day excursion to the granulites and migmatites near Port Edward on the KZN coast.

The IMSG conference started with an ice-breaker event on Sunday afternoon, and the participants enjoyed the refreshments and tasty food that was catered to them. The first day of the conference focused on granites and crustal processes. There were 17 talks on three main topics.

• Granitoids: This session covered the formation (igneous petrology), age (geochronology), chemistry (including scandium), and alteration (metasomatic phenocryst modification) of granites.
• Metamorphism and Granites: Talks in this section discussed the origin of giant crystals (megacrysts) in granites, how the Earth’s crust deforms (crustal tectonics), and a specific case study of deformation in Namibia.
• Bushveld Igneous Complex: This session primarily focused on the formation processes (magmatic processes) of the mafic rocks in the complex but also included some talks on the chemistry of the granites within the complex and discussions about plots related to platinum group elements (PGE).
  
  

Due to dire weather predictions, the planned coastal field trip on the second day was rescheduled for Wednesday afternoon. Instead, the day was filled with talks in four main areas:

• Volcanic & Analytical Techniques: This session covered various methods for studying volcanoes and volcanic rocks, including paleomagnetism (ancient magnetic fields), analyzing thin sections of rocks, combining airborne magnetic data with ground data, and studying the oxygen isotopes in rocks from the Andes mountains.

• Structure & Metamorphism: The talks in this section focused on the deformation of rocks, including folding, shearing, ductile deformation (stretching and pulling), and shock metamorphism (caused by impacts like meteorites). Additionally, there was a discussion on the limitations of models that simulate how melted rock is injected during impacts.

• Granitoids (II): This session was built on the first day’s granite discussions, with a focus on granites from the Kaapvaal Craton. Talks included using drones and remote sensing data alongside ground data to study these granites.

• Alkaline Rocks: This final session covered various types of igneous rocks with low silica content (alkaline rocks), including examples from the Arctic and Antarctic. Specific rock types discussed were carbonatites and anorthosites (rich in sodium and calcium plagioclase feldspar).
  
  

On the last day of the conference, the day began with nine talks that highlighted the following topics:

• Kimberlites and Mantle Chemistry (emphasis on megacryst chemical and isotopic compositions and on Cr in garnets) and Pegmatites (Kenya, Malawi, and (RSA) and Meteorites (the South African meteorite record of falls and finds).
  
  

The conference ended with a beautiful field trip to see rocks, granulites, charnockites, and pegmatitic granites near Port Edward. These rocks are around a billion years old and were studied by geologists like Geoff Grantham in the 1980s.

The IMSG ceremony closed with Student presenters thanking the organizers for creating a supportive environment for their research. The conference chair thanked the IMSG organizers and venue staff. Student awards were presented, with Dr. Robyn MacRoberts winning for her study on metamorphism in the Damara Belt, Namibia.

The award for best Master’s research presentation went to Gobona Lizzie Tau (University of Johannesburg) and Cimera CoE Manager for her work on localized ductile shearing along the northern margin of the Johannesburg Dome – a record of contractional tectonics at ca. 2.1 Ga on the Kaapvaal Craton. Llelani Coetzer (Stellenbosch University) received an honorable mention for her presentation on the Darling Batholith.