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Back to the field…

First time in the field since CoVid… it was a rainy November in Barberton, but nevertheless it has been a productive trip.

The middle of the Hooggenoeg formation. H3c chert (left) overlying pillowed H3v volcanics (right).

Steve and Marcel both discovered Barberton geology. Marcel mapped and sampled components of the syenites around Badplaas. Steve, despite some car adventures in the mountains, reached various chert bands and sampled good sections below them.

Let’s reach this chert !

Laurine, together with Alain and Jérémie, went hunting for addits, pit, trenches and disused mines to explore the structures of the quartz veins. They also have several tales to tell regarding unexpected encounters in the field, in particular with the various illegal miners who haunt the same places…

We were also fortunate to spend a bit of time with Christoph Heubeck (Uni Jena), currently organizing an ICDP drill project in the Moodies group. Christoph was kind enough to show us the drill sites, and also some other bits of geology around…

This is drill site #1 of ICDP base project. On that day, they were struggling to get through unconsolidated muddy soil, and were about to reach hard rock.

And lastly, the Stellenbosch crew (Gary, Alex, Bjorn, Tahnee, Mariana) came and met us for a few days, and we had an impromptu BuCoMO general assembly in the field…

Making up for lost time… BuCoMO students hard at work in Badplaas !

Of course, returning to France proved a bit more difficult that expected for the French component of the trip…

Actually, returning to France was the easy bit. The hard part is to explain to the CNRS why we had to modify our plans and to get our expenses refunded…

Laurine Travers, Steve Kitoga, Marcel Vinicius, Tahnee Otto, Mariana Werle, Jérémie Lehmann, Alain Chauvet, Gary Stevens, Alex Kisters, Bjorn van der Heyden, Jean-François Moyen – Nov. 2021

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Welcome to our new PhD students !

At the end of 2021, we are glad to welcome three new PhD students into the BuCoMO project.

Steve Kitoga will embark on a project on the link between alteration of Archaean sedimentary rocks, and geochemical signatures in TTGs (as advertised here). Steve is a graduate from UJ, where he obtained a MSc degree under Prof. S. Tappe, with outstanding marks (85 %). CoVid willing, he will start in Stellenbosch in October ’21, be in the field in Barberton in November, and come to France (Clermont-Ferrand) late in 2022. This is truly a collaborative project involving many tools and places: JF Moyen (Clermont-Ferrand / St-Etienne), Gary Stevens (Stellenbosch), Maud Boyet (Clermont-Ferrand), Johanna Marin-Carbonne (Lausanne).

Marcel Vinicius Santos Leandro is starting a Stellenbosch-based PhD, under the supervision of Gary Stevens, and co-supervised by Alex Kisters and Jean-François Moyen. He did his undergraduate in Geological Sciences (2018) and master’s degree (2021) at the Federal University of Sergipe (Brazil). His doctoral research includes petrology, geochronology and isotope geochemistry, to understand the correlation between the Archean alkaline magmatism (i.e., ~3.1 Ga Boesmanskop Complex) and previously crustal recycling in the Kaapvaal Craton. Marcel will join us during the Nov’21 trip.

Brian Mapingere is also a UJ graduate, working towards his PhD degree with Jérémie Lehmann (and some input by Alain Chauvet, we hope he will be able to truly benefit from the BuCoMO collaboration). His work is structural and investigates the link between gold and deformation in the Mwanesi Greenstone Belt in Zimbabwe.

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New phD offer

As of July 2021, this PhD has been awarded to Steve Kitoga.

We are happy to announce that we have available funding for one PhD project, to start in October 2021, working on the geochemistry of Archaean TTGs in Barberton. This project will be multi-national with a portion in Clermont-Ferrand (France), a portion in Stellenbosch (South Africa) and a component in Lausanne (Switzerland). See the atatched pdf for details.

Enquiries with J.-F Moyen

Application on CNRS jobs portal

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Laurine completes a M2, and starts a PhD

Laurine Travers enrolled in a M2 in Montpellier with A. Chauvet, co-supervised by J. Lehmann at UJ. She was fortunate enough to manage a very succesful field trip in Malolotja, and of course the rest of the project was somewhat “covided”. She nonetheless succesfully completed and defended her MSc, and then got a PhD grant from Université de Montpellier to carry on on the same topic, with the same supervisors.

Laurine is working on the structural control of Gold mineralization in the Barberton belt. Congratulation for a succesful master and welcome and best of luck for your PhD !


Laurine Travers, Jun. 2020

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Hugo completes his M2

In June 2020, despite complicated conditions…

Hugo Dominguez-Carranza started with BuCoMO for a M1 internship in Stellenbosch, and he carried on for his M2 (based in Lyon). He did field work in Limpopo in late 2019, under unseasonal rains, and then he was in Stellenbosch in March 2020 when the world became crazy. He was repatriated by his University, literally catching the last flight out of Cape Town before the airport closed. After which he was in lockdown for the rest of the time, and to his credit he nevertheless managed to propose a very nice Masters, that he defended (remotely) in June 2020.

You can read his work here:

We are also very glad to announce that Hugo accepted a PhD position in Bern, to work in Pierre Lanari’s CPaG group.

Congratulations !


H. Dominguez-Carranza, June 2020

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Malolotja

In February 2020, three of us (Alain Chauvet, Jérémie Lehmann and Laurine Travers) went to Malolotja in Swaziland, in the (comparatively poorly known) Southern portion of the Barberton Greenstone belt. The goal was to understand the structural context of quartz and carbonate veins, and possibly of gold mines.

This was part of Laurine’s MSc (M2) work in Montpellier. Laurine has meanwhile obtained a PhD grant from Univ Montepplier (well done !) and will carry on on this project, as a “cotutelle” between Montpellier and Johannesburg.

Laurine’s work is closely related to a new MSc project at UJ by Biran Mapingere, undergoing similar studies in the Mwanesi Greenstone Belt of Zimbabwe.

Model for the formation of mineralized veins in Southern BGB. (c) Laurine Travers, 2020.

A. Chauvet, J. Lehmann, L. Travers. Feb. 2020

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BuCoMO goes Nature

We are very pleased indeed to report that BuCoMO’s first contribution to Nature (geoscience) is just out:

You want to read the whole story, here. It is based on TTG granitoids in the Southern part of the Barberton Terrain

… where the outcrops are not bad at all…

… and the rocks nice and fresh !

The story draws on petrology, geochemistry and geochronology and offers an unconventional view on the origin of Archaean granitoids, and the formation of Earth’s oldest continental crust.


O. Laurent & many others, Jan. 2020

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Field work in Limpopo

Hugo Dominguez-Carranza did a Masters project (French M1 + M2) looking at metamorphic rocks in the Southern Marginal Zone of the Limpopo belt. In December 2019 we went for a few days in the field, under an un-seasonal rainy, grey and even cold (!) weather and sampled some beautiful rocks…

A typical Limpopo outcrop: the bed of the Sand River at Petronella

Of course, as we all know there are some amazing granulites to be found there.

The specialists will enjoy the following photo:

Cordierite rimmed by garnet (yes, not the reverse !) in the Northern edge of the “retrogressed zone”.

Hugo did a very neat petrological study (and P-T modelling), despite the fact that he spent most of his time in lockdown (not to mention the stress of being repatriated from south Africa on the absolute last flight that left Cape Town in March…)


G. Stevens, J. Diener, H. Dominguez-Carranza, JF Moyen, December 2019

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Sampling the Aigoual Pluton

Mont Aigoual, in Southern Massif Central, is a very scenic place (and also rather cold, in late November).

It is built on top a a nice Carboniferous granite, and the tip of this pluton grades into spectacular dykes with the most unusual texture.

We sampled those during a quick trip, for a MSc project by Mariana Werle (Stellenbsoch).

Not to mention a memorable duck meal at the inn in the evening !


G. Stevens, JF Moyen. November 2019