Meet an Earth scientist!
Page last updated:13 October 2026
We sat down to chat with Dr Kristy Guerin, who is a geochemist here at Geoscience Australia, to find out about her work and the path that she took to Earth science.
A curious mind
Dr Kristy Guerin's journey into Earth science wasn't a conventional one. After spending 10 years working as a nurse, she returned to university to pursue a new interest in geology. She went on to complete a PhD and now works as a geochemist in Geoscience Australia's Critical Minerals team.
What does a geochemist do?
Lasers! X-Rays! Acids! Kristy gets to use them all. Geochemistry is a field of geology that looks into the chemical elements that make up a rock. Whether it’s an element or a mineral, Kristy can identify it. And some of the traces are really small! As she says, it’s like looking for one specific ball in a ball pit of a million balls.
The work that Kristy and her colleagues do is looking into some of the fundamental questions about our planet: how did it form? What is it made of? How do the different physical processes of the Earth interact with its physical substance? These questions and more make geochemistry one of the most fascinating fields in Earth science.
And if you’re a geochemist, Australia is a great place to work. Kristy explained that Australia, being a very old and very large continent, has an incredibly diverse range of geology just waiting to be studied and understood.
The chemistry of critical minerals
Kristy's work helps improve our understanding of where critical minerals occur and the geological conditions associated with them. By studying the chemistry of rocks and minerals, Geoscience Australia can identify patterns and provide data that help industry make more informed decisions about where to explore. This information can support more targeted exploration, potentially reducing costs and unnecessary disturbance while helping Australia better understand its critical mineral resources.
This work has enormous benefit for the critical minerals industry. The data that we produce allows industry to focus their efforts on areas where they will have the best chance of success. This helps improve efficiency for industry and, equally importantly, reduces the amount of unnecessary exploration.
The future of geochemistry
Critical minerals are in every aspect of our modern lives so Kristy and her team will be kept very busy for many years to come! As she says, there are a lot of Earth science courses available through universities and it is a field that is constantly growing and evolving.
If you’re a student who might be interested in working in the Earth sciences, have a chat to your science teacher or visit to the Earth science school at a local university, if you have one nearby. And don’t forget, it’s never too late to become interested in Earth science! If Kristy hadn’t taken the plunge to change careers, we wouldn’t have a very talented and dedicated geochemist on our team.