University Of The Witwatersrand Takes Lead In Global Innovative Seismic Testing Project For New Generation Exploration
The testing phase of a SA-Europe partnership project this December marks a significant step forward in developing new generation seismic sensing technology.
The FUTURE (Fibre optic sensing and UAV-platform techniques for innovative mineral exploration) Project is funded by a consortium of European-South African governmental agencies for the next two years and sees Wits step up as project lead. It pulls together collaborators from the University of Venda, Uppsala University in Sweden, Politecnico di Torino in Italy as well as Geological Survey of Sweden (SGU) and French company Sercel. Stakeholders such as Nordic Iron Ore in Sweden and Gold Fields in South Africa are also partners and benefit from the outcome of the solutions.
In this latest phase of the project, the global team of 22 researchers and scientists gathered in South Africa to set up an array of 400 wireless sensors for active and passive recording at Gold Fields’ South Deep Mine operations in Westonaria, which is among the world’s deepest gold mines.
The project has been a breakthrough in synchronising a range of seismic testing on a working mine and also to meet the aims of being cost effective and environmentally sensitive in its research footprint.
Professor Musa Manzi from Wits School of Geosciences, co-ordinator of the FUTURE project, says: “For the first time we’re deploying wireless sensors on the surface as well as sensors in mine tunnels and in boreholes in such a scale. This testing is also all being done in on an active production mine at a depth of about three km, that’s so remarkable. “
“We have continuous recording on surface and we’re testing a prototype GPS-time system developed under the Smart Exploration Project that can be used inside a mine tunnel or GPS-denied environment. So, we are synchronising surface sensors with tunnel sensors and also using fibre optic sensing cables so that we have both passive and active seismic recordings to map the ore body and complex geological structures ahead of the currently mined-out area.”
Manzi says extending the life of mines and achieving sustainable extraction of critical metals at deeper levels are the next direction for modern mining. But he says it will call for greater emphasis on technology and innovation for safer ways to mine, mitigating risks, ensuring less impact on the environment and being able to keep costs down.
Their testing at South Deep mine has made use of a mini mobile seismic vibration machines that causes less damage to the environment but is powerful enough to send vibrations three kilometres underground to be recorded and analysed as sound waves. He adds that having more comprehensive seismic data means better analysis and mapping. In turn, it means more accurate identification of viable ore bodies and being able to mitigate risks associated with deep mining such as mining-induced seismicity.
For Manzi and his European colleagues this project has been 18 months in the making. It successfully merges multiple research targets at this one site in the spirit of deepening scientific understanding, knowledge sharing and skills transfer especially between the cohort of up and coming young scientists from South Africa, Sweden and Italy.
Manzi adds: “One of the key strengths of this project is that we have a lot of young professionals – postdocs, PhD and MSc students. It’s important for them to be exposed to this level of scientific research and also to be able to start creating their networks with other young people from different countries, because in the next five or 10 years they will be developing their own projects and technologies that can enhance the future of sustainable mining and mineral exploration for the next generations.”
Geophysicist Professor Valentina Socco at Politecnico di Torino in Italy is one of lead researchers and partner on the FUTURE project. On this project she has focused on modelling and analysing guided seismic waves in the South Deep mining tunnels. Socco says guided wave records can be processed to generate images that give geophysicists better understanding of the properties of the materials and minerals that lie behind the tunnel walls.
“It means that one can get closer to the target exploiting existing mine infrastructure – like the established tunnels – more effectively,” she says.
Socco says the research from the FUTURE project has potential to inform how Italian mining can be revived after a downturn for close to a century already. It needs to make a comeback that using cleaner and smarter technologies for exploration.
She adds: “South Africa has a unique geology so it’s a very important opportunity for us to be able to work on a pilot project at the depths of South Deep mine because in Italy, we don’t have such operations.
“With the FUTURE project we can work with colleagues to integrate different approaches to improve our global capability.”
For Professor Alireza Malehmir from Uppsala University in Sweden, he and Manzi have enjoyed years of collaboration, testament to how universities can forge stronger partnerships for shared knowledge building. He and his students under the FUTURE project banner have focused on using fibre optic seismic sensing for collecting big data sets for processing and mathematical modelling.
Malehmir says the data from seismic testing in South Africa has the potential to enhance Sweden’s ability to find mineral resources in hardrock environments and to be able to apply the techniques for “upscaling and for commercial surveys”. Future applications could also include the likes of identifying sites of carbon capture and storage, an essential component in adapting to a world facing a climate emergency. Opportunities are tremendous if realised.”
Malehmir adds that the success of the FUTURE project in this phase of the testing lays stronger foundations for long-term collaborative research that will impact industry positively. But he says the practical experience has had great value in sharpening different skillsets for the students.
“Students taking part in this project have been able to have hands-on learning and to work with modern equipment directly. They’ve also been able to understand and see how data they use are collected. Importantly, they’ve also learnt to develop their managerial skills in managing a big project like this and understanding what it takes to pull together so many different elements.“
“It is a different kind of challenge but it allows them to also think like managers, like entrepreneurs, and to become people who note problems and find solutions,” he says.
The Swedish, Italian and French teams return to the home countries in the middle of December but the next in-the-field phase of the FUTURE project will resume with more active testing in the first quarter of 2023 in South Africa.