Chris Kirkland, one of the authors of the study, caught up with Liam McAneny on the Space Connect podcast to explain the team’s findings.
The research has revealed new data about the impact of the movements of the solar system through the Milky Way galaxy upon the creation of Earth’s crust billions of years ago.
While the team is focused on looking backwards through time, the data they are gathering has some important consequences for the modern world.
“It’s important because the crust is where we live, but it’s also where we find the majority of our ore deposits. It’s also what hosts the majority of Earth’s biomass.
“So obviously we’re interested in when geological processes happen because that can help us predict where they might occur. If we know for example, that an ore body forms at a specific time when two mountains collide into each other, we can go and look for similar ages or rocks elsewhere,” Kirkland said.
The study also has significant implications for astronomers and astrophysicists, revealing how the movement of celestial bodies through their galaxies can impact upon the formation of planets.
Kirkland’s study describes a “rhythm” within the formation of the Earth’s crust, thanks to the process of molten magma from the Earth’s mantle cooling on the crust into solid rock and trapping uranium and other elements and minerals.
One of the key findings of their research was the evidence that meteorite impacts on Earth also followed a “rhythm” with more frequent and powerful impacts detected during times when our solar system moved through the spiral arms of our galaxy.
The team believes the impacts were caused by cosmic material being ejected from the Oort cloud, a distant mass of icy material in the far reaches of the solar system.
“The interesting thing is that because of the orbits of the cometary material coming from the Oort cloud, they're going to hit with massively higher impact energy,” Kirkland said.
“That then becomes important because the impact energy is directly proportional to the amount of melting that is produced, which is directly proportional to the amount of new crust [that is] formed on the planet.”
The team at Curtin gathers the majority of their data from the Pilbara Craton, which Kirkland explained is “a stable block of crust that’s not been destroyed and lasted for a long time”.
He also touched on the reasons why this geological formation is so invaluable to researchers.
“We’re very lucky in Western Australia that we’ve got the Pilbara Craton in our back door. And it’s one of these places that’s really special because it contains this archive of deep time.”
“It’s important because the processes it retains are early Earth processes. They're not the standard process we see everywhere else,” he said.
Liam McAneny is a journalist who has written and edited for his University International Relations journal. He graduated with a Bachelor of Arts (International Relations) and Bachelor of Laws from the University of Wollongong in 2021. He joined Momentum Media in 2022 and currently writes for SpaceConnect and Australian Aviation. Liam has a keen interest in geopolitics and international relations as well as astronomy.
Send Liam an email at: [email protected]
Receive the latest developments and updates on Australia’s space industry direct to your inbox. Subscribe today to Space Connect here.