Curtin University researchers have demonstrated a major new method to uncover the ancient history of Australia’s landscapes, offering vital insights into how the environment responds to geological processes and climate change — and even where valuable mineral deposits may be found.
The international research, led by Curtin’s Timescales of Mineral Systems Group at the School of Earth and Planetary Sciences, was conducted in collaboration with the University of Göttingen and the University of Cologne.
The team studied tiny crystals of zircon found in ancient beach sands, using them to reconstruct the deep-time evolution of Earth’s surface.
Zircon is one of the most resilient minerals on Earth, enduring weathering, erosion and transport across rivers and coastlines over millions of years.
Trapped within its structure lies a rare gas called krypton, produced when the mineral is exposed to cosmic rays — high-energy, charged subatomic particles that constantly bombard the planet from space.
By capturing and measuring the quantity of krypton within the zircon, scientists were able to determine how long the mineral grains remained exposed at the Earth’s surface before being buried.
Acting as a kind of “cosmic clock,” this method provides a direct window into how quickly landscapes eroded or evolved through geological time.
Lead author and Adjunct Curtin Research Fellow Dr Maximilian Dröllner, also from the University of Göttingen, said the new technique allowed scientists to investigate much older landscapes than previously possible.
“Our planet’s history shows climate and tectonic forces can control how landscapes behave over very long timescales,” Dr Dröllner said.
“This research helps us understand what happens when sea levels change and how deep-seated Earth movements influence the evolution of landscapes.”
The findings revealed that when landscapes are tectonically stable and sea levels remain high, erosion slows substantially.
Under these conditions, sediments can remain at or near the surface for millions of years, preserving environmental evidence and allowing more gradual geochemical changes to occur.
Co-author and Timescales of Mineral Systems Group lead Professor Chris Kirkland said the study’s implications extended from understanding planetary evolution to informing future land management and planning.
“As we modify natural systems, we can expect changes in how sediment is stored in river basins and along coastlines and continental shelves,” Professor Kirkland said.
“Our results show that these processes can fundamentally reshape landscapes, not just coastlines, over time.”
Associate Professor Milo Barham, also a co-author from the Timescales of Mineral Systems Group, said the research could also influence how scientists understand and locate Australia’s mineral resources.
“Climate doesn’t just influence ecosystems and weather patterns, it also controls where mineral resources end up and how accessible they become,” Associate Professor Barham said.
“Extended periods of sediment storage allow durable minerals to gradually concentrate while less stable materials break down, explaining why Australia hosts some of the world’s most significant mineral sand deposits.
“Understanding these links is critical as demand for these minerals continues to grow, as it provides a long-term perspective that can improve models used to predict future environmental and resource outcomes arising from changes to these sediment systems.”
The study, Ancient landscape evolution tracked through cosmogenic krypton in detrital zircon, was published in PNAS.
