Funding: DFG - SPP 1006 ICDP

Project period: 2022 - 2025

Project staff: Dr. Jens Kallmeyer

Partners: 

• Prof. Yohey Suzuki, University of Tokyo, Japan

• Prof. Julio Castillo Hernandez, University of the Free State, University of Huelva, South Africa

• Prof. Kgabo Mogadeni, University of Limpopo, South Africa

Bushveld is by far the world's largest igneous intrusion, with a diameter of about 300 km and a thickness of about 10 km. The volume is on the order of 1 million cubic kilometers. These numbers qualify Bushveld as a Large Igneous Province or LIP. There are several such LIP provinces on Earth, including the Karoo in South Africa, and they are thought to form when plumes of hot material rise from the core-mantle boundary, causing large-scale melting of the upper mantle and even parts of the crust. The huge transfer of mass and heat into the upper crust can generate world-class metallic ore deposits, and surface volcanism can have a profound influence on climate. 

The Bushveld has been a target for ICDP for a long time, but only in 2021 a proposal was finally approved. Industry donated close to 10 km of drill core as an in-kind contribution which proved to be highly valuable for petrologists, but unsuitable for microbiological research as these cores had been drilled without any contamination control, they had also been stored aerobically (in contact with the atmosphere) for many years. The actual drilling only started in 2024, on the grounds of Marula Platinum Mine. 

From a geomicrobiological perspective, this is a high-risk project as it was not clear whether suitable material could be recovered. Therefore, this first phase of the project focuses exclusively on establishing contamination control during drilling and sample acquisition. 
Drilling so far has been successful and recovered suitable core material from the surface down to well over 1 km depth. In cooperation with the University of Limpopo, core sections were secured for microbiological analyses, cleaned from excess drill mud and stored anaerobically.

Luckily, in cooperation with partners from Japan and South Africa, a first study was already published (Suzuki et al., 2024). Drilling is supposed to finish in June 2025, and further funding for sample analysis will be applied for in the future.