Small iron-rich formations discovered in the Pinnacles of Western Australia, which belong to the largest wind-driven limestone belt in the world stretching over 1000 kilometers, have shed new light on the planet’s ancient climate and shifting landscapes.
Small iron-rich formations discovered in the Pinnacles of Western Australia, which belong to the largest wind-driven limestone belt in the world stretching over 1000 kilometers, have shed new light on the planet’s ancient climate and shifting landscapes.
Recent studies indicate that these pinnacles were created roughly 100,000 years ago during the wettest era in the last 500,000 years for the region, a stark contrast to today’s Mediterranean climate of Western Australia.
Dr. Matej Lipar, the lead author and an Adjunct Research Fellow at Curtin’s School of Earth and Planetary Sciences, currently affiliated with the Research Centre of the Slovenian Academy of Sciences and Arts (ZRC SAZU), explained that the remarkable finger-like stone formations in Nambung National Park are a type of karst structure formed as water erodes rock.
“These structures provide vital information about ancient climates and environments, but pinpointing their age has been quite difficult until this research,” said Dr. Lipar.
“Karst landscapes, like those found in Nambung National Park, exist around the globe and are sensitive indicators of environmental change. By studying them with accurate timelines, we can gauge how Earth’s geological systems react to climate changes.”
“Our findings reveal that this wet era was the most significant in the last 500,000 years, setting it apart from other parts of Australia and unlike the present-day Mediterranean climate of Western Australia.”
“The surplus of water during this period led to the dissolution of limestone, resulting in the unique pillars found in the Pinnacles and creating favorable conditions for the formation of iron nodules.”
Curtin co-author Associate Professor Martin DaniÅ¡Ãk, part of the John de Laeter Centre, noted that the iron-rich nodules function like geological clocks, capturing helium from the steady radioactive decay of small amounts of naturally occurring uranium and thorium.
“By measuring this helium, we can obtain an accurate record of when these nodules were formed,” Dr. DaniÅ¡Ãk explained.
“The cutting-edge dating methods utilized in this study indicate that the nodules are approximately one hundred thousand years old, revealing an exceptionally wet climate period.”
Study co-author Associate Professor Milo Barham, from Curtin’s Timescales of Mineral Systems Group in the School of Earth and Planetary Sciences, highlighted the importance of reconstructing past climate changes, as it offers context for understanding human evolution and broader ecosystems amidst significant climate fluctuations over the past three million years.
“This new insight will deepen our understanding of global environments and ecosystems, equipping us to prepare for and lessen the effects of a warming planet,” Dr. Barham noted.
“This research not only contributes to scientific knowledge but also provides practical insights into climate history and environmental changes that are relevant to anyone concerned about the future of our planet.”
This research project was a collaborative international effort with ZRC SAZU and received support from the Slovenian Research and Innovation Agency.
