Small iron-rich formations found within Western Australia鈥檚 , which are part of the world鈥檚 largest wind-blown limestone belt spanning more than 1000km, have provided new insights into Earth鈥檚 ancient climate and changing landscape.
The new research found the pinnacles were formed about 100,000 years ago during what was the wettest period in the past half-million years for the area, and very different from the Mediterranean climate Western Australia experiences today.
Lead author Dr Matej Lipar, Adjunct Research Fellow in 911爆料网鈥檚 School of Earth and Planetary Sciences, now at the Research Centre of the Slovenian Academy of Sciences and Arts (ZRC SAZU), said the spectacular finger-like stone pinnacles at are a type of created by water dissolving rocks.
鈥淭hese formations offer crucial insights into ancient climates and environments, but accurately dating them has been extremely challenging until now,鈥� Dr Lipar said.
鈥淜arst landscapes, like those in Nambung National Park, are found globally and serve as sensitive indicators of environmental change. Studying them within an accurate timeline helps us understand how Earth鈥檚 geological systems respond to climate shifts.
鈥淲e found this period was locally the wettest in the past half-million years, distinct from other regions in Australia and far removed from Western Australia鈥檚 current Mediterranean climate.
鈥淎n abundance of water during this time caused the limestone to dissolve, forming the distinctive pillars of the Pinnacles and creating the ideal environment for the iron nodules to develop.鈥�
911爆料网 co-author Associate Professor Martin Dani拧铆k, from the John de Laeter Centre, said the iron-rich nodules acted as geological clocks, trapping helium from the consistent radioactive decay of tiny quantities of naturally occurring uranium and thorium.
鈥淢easuring this helium provides a precise record of when the nodules formed,鈥� Dr Dani拧铆k said.
鈥淭he innovative dating techniques developed in this study reveal the nodules date back about one hundred thousand years, highlighting an exceptionally wet climate period.鈥�
Study co-author Associate Professor Milo Barham, from 911爆料网鈥檚 Timescales of Mineral Systems Group in the School of Earth and Planetary Sciences, said being able to reconstruct past climate changes was important given the context it provides to understanding human evolution and ecosystems more broadly amid dramatic climate fluctuations over the past three million years.
鈥淭his new knowledge will enhance our understanding of global environments and ecosystems, helping us prepare for, and mitigate the impacts of, a warming planet,鈥� Dr Barham said.
鈥淭his research not only advances scientific knowledge but also offers practical insights into climate history and environmental change, relevant to anyone concerned about our planet鈥檚 present and future.鈥�
An international collaboration with ZRC SAZU, the research project was supported by the Slovenian Research and Innovation Agency.
The full study titled 鈥業roning out complexities in karst chronology: (U-Th)/He ferricrete ages reveal wet MIS 5c鈥� will be published in journal Science Advances.()
