Key points
- Our Deep Earth Imaging Future Science Platform (DEI-FSP) has developed innovative imaging technologies that dramatically enhance our understanding of Australia's subsurface structures.
- The initiative has fostered significant advancements in geoscience, allowing researchers to integrate diverse data sets for comprehensive analysis.
- As the DEI-FSP concludes, its legacy includes both an enhanced scientific toolkit and a new generation of skilled researchers.
What riches lie beneath the Australian continent’s complex sedimentary layers?
This is the question our Deep Earth Imaging Future Science Platform (DEI-FSP) set out to answer. It combined different scientific domains to develop new imaging and modelling techniques, revealing the secrets of the country’s underexplored areas.
Our Future Science Platforms are investments in science that underpin innovation. They have the potential to help reinvent and create new industries for Australia and can help us grow the capability of a new generation of researchers.
FSPs typically run on a lifecycle of around five to eight years. After this period, the technology and outputs developed become part of our broader CSIRO science portfolio.
After seven years of refining and fusing gritty data, our DEI-FSP has matured. The team will disperse in June 2024 to the promised land – the future of resource discovery.
When launched, the platform had multiple mandates. These included forming cross-disciplinary collaborations, engaging post-graduates and post-doctorates, and building research capabilities. As it comes to an end, it has enriched national and international understanding of how to more accurately map the Earth’s subsurface.
Building regional resource security
The platform’s triple focus was to understand what characterises Australia’s reserves of minerals, water, and energy. This will help to make exploration less risky, sustainably manage resources, and build regional energy and resource security.
The platform began in 2016 as one of six frontier science platforms. Together, they planned to turn Australia's scientific challenges into opportunities and invent a better future. The DEI-FSP recognised the need to bridge the groups of expertise in order to answer emerging complex questions.
For example, most of the minerals recovered in Australia so far have been drawn from only 20 per cent of its landmass – the area of exposed or shallow crust. How do we define and harvest the resources locked in the remaining 80 per cent? We know this includes a deep and varied covering of sediments and weathered material.
Juerg Hauser is a mathematical geophysicist on our team. He led the platform’s Advanced Inversion Techniques program.
“Many have suggested this 80 per cent of covered territory could be as rich as the more accessible 20 per cent,” Jeurg said.
Inference: where scientific data meets mathematical innovation
Inference, in this context, refers to the mathematical methods researchers use. These methods allow them to deduce (infer) properties of the subsurface based on a variety of measurable parameters. You might use several measurable physical properties to infer rock types or their characteristics, such as how porous it is.
Juerg suggests mineral prospectors need more sophisticated ways to analyse old and new data. This is necessary to answer complex scientific questions.
“On the science side of things, we have experts who want to use the data for certain questions, but they can no longer easily access the mathematical knowledge to be successful,” Juerg said.
“On the other hand, you have people developing sophisticated inference methods and mathematical concepts, but they may not directly see the application in resource discovery."
Helping with this is the multi-faceted geodata inference research centre, or InLab. It’s a legacy of the DEI-FSP, which allows industry and geoscience researchers to use and understand leading-edge mathematical inference concepts. These concepts can offer new perspectives on their analysis of the Earth’s subsurface.
InLab emerged from a collaboration between the DEI-FSP and the Research School of Earth Sciences at the Australian National University.
Tim Munday is an expert in the application of airborne geophysical methods of exploration. He has been Research Director of the DEI-FSP since 2019.
“We’ve started to push it out more broadly as a collaboration platform for experimenting with ideas in the world of inference,” Tim said.
Out of their silos and into the forge of combined ideas
Erdinc Saygin, a computational and observational seismologist has led the Geoscience Imaging focus of the DEI-FSP. He considers human capital "the biggest achievement of the DEI-FSP".
More than 20 new research scientists were recruited, building a pipeline of new talent. Some are now professors in other institutions in Australia and internationally. Meanwhile, others have moved into new business units where they are continuing their crust-busting work.
"One of the most important benefits for researchers was to be exposed to multidisciplinary activities,” Erdinc said.
“For me, it was discovering the world outside seismology that potentially complements my area of expertise – it has been a great learning insight.”
As well as the cross-discipline work, several papers on the platform’s novel findings have been published during its lifetime. This includes one from Erdinc’s team on a new technique that adds value to legacy data, Chen, Y., Saygin, E. (2020). Empirical Green's Function Retrieval using Cross-correlation of Ambient Noise Correlations (C2), J. Geophys. Res.-Solid Earth, doi:10.1029/2019JB018261.
“It’s important because data collection is an expensive and arduous process. With this technique we piggyback on the existing data sets and improve the resolution,” Erdinc said.
“Better resolution leads to potentially better exploration outcomes.”
Harnessing seismic shifts in perspective
In 2023, the group’s Yunfeng Chen (Assistant Professor in the School of Earth Sciences at Zhejiang University in China), was the lead author of Next-generation seismic model of the Australian crust from synchronous and asynchronous ambient noise imaging. The paper was published in the journal Nature Communications.
The open-access paper provides an updated 3D shear-velocity model of Australian subsurface structures. The model was derived from a massive dataset, containing nearly 30 years of seismic recordings from over 1600 stations.
It uses a new ambient noise imaging workflow that enables improved data analysis by integrating non-synchronous arrays across the continent. Essentially, it uses innovative techniques to combine different sets of seismic data, even if they weren't recorded at the same time. This allows for more accurate and comprehensive analysis of geological structures beneath the surface.
Technology developed in the DEI-FSP's Geoscience Imaging program can now map minute changes in the subsurface. This will allow minimally invasive monitoring of groundwater, tailings dams, and carbon dioxide (CO2) storage.
The nature and utility of underground water resources
When the DEI-FSP was first established, there was an understanding that data sets collected in one thing would have application for others. Hence, the inclusion of energy and water exploration in the platform’s scope.
Tim anticipates new technologies and workflows will make a significant contribution to the new energy space. This could include identifying natural hydrogen reservoirs and opportunities for CO2 sequestration.
“There's also a growing appreciation that you can't really develop a mine unless you have water. So, if you want to successfully develop a mineral resource in remote parts of Australia, it’s important to understand where the water is in relation to the minerals,” Tim said.
Tim’s work on the South Australian G-FLOWS project was conducted in collaboration with colleagues in our Environment team, Flinders University and the South Australian Government under the auspices of the Goyder Institute for Water Research. They were successful in developing methods for identifying long-term outback water solutions in the form of subsurface palaeovalleys, or ancient, buried river valleys.
The initial project focused on Aṉangu Pitjantjatjara Yankunytjatjara (APY) lands in the arid northwest of South Australia. It investigated the potential of water-bearing palaeovalleys to support regional communities. These communities had been occasionally forced to truck in water. There were also enterprises such as mining and grazing that needed water.
Once again, multidisciplinary evidence from the platform was used to draw a more accurate and detailed picture of palaeovalley extent and geometry. In this case, it included the application of airborne electromagnetic surveys, one of Tim’s areas of expertise. When linked to drilling information and groundwater chemistry, this information provides a framework for sustainable resource development.
Pushing the boundaries of seismology
“I joke with Tim that this is his Mission Accomplished moment, but that's not how science works. The more you know, the more you see the next thing on the horizon, and the next, and the next,” Jeurg said.
Juerg’s passion project, InLab is a valuable resource for industry and researchers to efficiently test new methods of inference. He is confident our ongoing collaboration with the Australian National University on InLab will find an enabling funding model.
Erdinc looks forward to a plethora of choice in upcoming collaborations.
“In seismology, some of the things we've developed over the past seven years are of great interest to industry, especially in terms of reducing exploration costs, and also improving the seismic imaging resolution.”
Tim concludes that the strides taken by the Deep Earth Imaging Future Science Platform have been significant.
“We have progressed the science of subsurface understanding. We’ve lifted national and global capability,” he said.