Department of Earth and Environmental science (James Cook University)
Using geology to power the green energy revolution: understanding fluid migration in rocks to find new rare earth element deposits
Rare earth elements are a group of elements needed to make wind turbines and other green energy technology. The future demand for these elements is predicted to be far greater than current supplies. Queensland has many rare earth element deposits, but we don’t completely understand how they formed, which prevents us from finding new deposits. One common type of deposit forms when rare earth elements are dissolved in a fluid that migrates through rocks in the crust in zones of deformation, called shear zones, to a place where the ore deposit forms. We don’t understand how this happens. My work uses numerical modelling and advanced geochemical techniques to understand this process on the micro scale. The outcomes of this work will allow identification of which shear zones moved rare earth element-rich fluids in the past, pointing us toward new, undiscovered mineral deposits now.
As we move toward net zero CO2 emissions by 2050, fossil fuels will be replaced by clean, renewable energy. Modelling has shown that workers in Queensland stand to be hit the hardest by the demise of the coal industry, as I outlined in an article in the Conversation (https://theconversation.com/how-australias-geology-gave-us-an-abundance-of-coal-and-a-wealth-of-greentech-minerals-to-switch-to-173988). However, the demise of the coal industry comes at the same time as new opportunities in renewable energy. One major opportunity is in mining rare earth elements, which are a group of elements needed to make wind turbines and other green energy technology. The global rare earth element market is valued at $US2 billion currently and is forecast to grow to around US$12 billion by 2030, with projections suggesting that the Australian market will undergo the greatest growth worldwide (Roskill, 2021). If geologists can help industry find new rare earth element deposits here in Queensland, there will be new industry and new jobs for Queenslanders.
Rare earth elements are concentrated into economic mineral deposits through geological processes. One common deposit type is skarn deposits, which have been a great source of wealth for north Queensland mining companies. Skarn deposits form when salty fluids rich in rare earth elements migrate out of deep rocks, travel in channels (fractures in the rock and zones of deformation) and focus into calcium-rich rocks causing rare earth elements to precipitate. Zones of deformation, known as shear zones, occur next to skarn deposits but there has been no research that investigates their role as a conduit for fluids that form the skarn deposit. Shear zones may also be the source of the rare earth elements, since it is impossible for a fluid to move through a shear zone without dissolving soluble elements and precipitating elements that become insoluble due to chemical reactions.
My research aims to understand how the fluids that form rare earth element deposits move through shear zones using detailed chemical analyses and numerical modelling. I have begun conducting field work at known skarn deposits in Mount Isa to determine the relationship between the shear zone and the deposit. I have extensive experience in shear zones and fluid migration in other parts of the world, and I am bringing this expertise to our rocks in Queensland. I am also using advanced numerical modelling techniques to understand how fluids move through deforming rocks at the grain scale, which will help us identify which shear zones are best for transporting ore-forming fluids.
This is a novel approach in skarn research because no one has ever understood the link between shear zones and rare earth element deposits before. Understanding the characteristics of the shear zone will tell us how skarn deposits form and what features we need to look for to find new ones. This will help us pinpoint skarn deposits that have remained hidden under the surface in Mount Isa, which will help mining companies make discoveries well into the future and power the green energy revolution and the Queensland economy into the future.
I believe that there are two parts to being a role model for women and girls: (1) being a strong advocate for gender equity, (2) being an excellent and visible science communicator
(1) being a strong advocate for gender equity
My advocacy work has two main pillars: (1) raising the profile of women in earth and environmental science and (2) raising awareness of current gender inequities.
To help raise the profile of women in earth and environmental science I became the President of Women in Earth and Environmental Science Australasia (WOMEESA) in October 2021. WOMEESA is a non-profit organisation that aims to create a supportive network for women in Earth and Environmental science across academia, industry and government. As President I oversee all of WOMEESAs many activities (detailed below) but my history of advocacy extends back further through initiatives to change geoscience culture within the community more broadly. I created a database of women in Earth, Atmospheric and Environmental science that media can use to find women experts, which is hosted through WOMEESA. I also created a seminar series for WOMEESA that has been running since 2020.
To raise awareness of current gender inequities I recently co-authored a peer-reviewed paper on gender equity in geoscience (Handley et al., 2020). The research I did for this paper prompted me to develop a presentation on why women leave geoscience, which I have been presenting in a roadshow for mining companies, at mining conferences, and at universities since 2020. Geoscience is one of the most male dominated and least diverse fields in science. Part of that is due to bias and poor culture within our discipline and industries, particularly the mining industry. My presentation aims to create a culture change by explaining why women leave our discipline and what we need to do to change that. These seminars have been well received by the community as indicated by the popularity of a recording of my December 2021 seminar for the University of Queensland, which has had more than 1500 views (https://www.youtube.com/watch?v=xO7_dOYGSvQ).
(2) being an excellent and visible science communicator
The best way to inspire women and girls to become scientists is to show them how amazing it is to study Earth processes. To reach the broader community I have harnessed the power of social media. In 2021 I ran a campaign called ‘100 days of geoscience’ where I posted on twitter and Instagram every day for 100 days. The photos were from my research with a geological explanation for each photo. This was hugely popular, and my twitter followers increased from 1000 before the campaign to over 3000 and my Instagram followers doubled. This campaign led to two radio interviews and a piece in the online blog geo-down-under (https://www.geo-down-under.org.au/100-days-of-geoscience/). I have also authored a number of popular science articles and appeared on TV, radio and podcasts, as detailed in the next section.
I am committed to creating change for girls and women in geoscience in Australia and beyond. As mentioned previously, I am the President of WOMEESA, a non-profit organisation that aims to create a supportive network for women in Earth and Environmental science across academia, industry and government. WOMEESA has more than 1000 members and hosts a range of events that provide professional development and networking opportunities. Among these we have a monthly seminar series, mentoring groups, interactive workshops, a database of women scientists used by media to find women experts, and Wikipedia edit-a-thons to get profiles for all women professors in our discipline. I devised and built several of these initiatives, and now oversee them all and manage our wonderful committee of volunteers.
Beyond the work of WOMEESA I have also presented seminars and written papers on gender equity in geoscience (detailed in the last section). In addition to this I have been on TV and radio talking about gender equity. On International Women’s Day last year I appeared on channel 7 news and was interviewed for the Townsville Bulletin to highlight current issues in gender inequality and ways to improve STEM for women.
I was a 2021-2022 STA Superstar of STEM, a program that aims to smash stereotypes and create role models. I have appeared on National and local radio talking about my research and about women in geoscience (for full details see https://melaniefinch.net/media-and-outreach/). I have written three articles for the Conversation, whose readership is dominantly non-academic women in their 20s. I wrote a piece about the geological formation of Uluru at the end of December 2021 and it has been read more than 80,000 times and picked up by other media outlets. I did a number of radio interviews in connection with that article, including on ABC breakfast, a national broadcaster. I also published an article about the demise of the coal industry and growth of renewable energy, and what that could mean for people working in the coal industry in Queensland, which has been read more than 20,000 times. I did a radio interview for that article too on radio 2NM in the Hunter Valley, which is an audience that is particularly important for me to reach because they will be disproportionately affected by the demise of the Coal industry.