Iron deposits in the Pilbara region of Western Australia are a lot younger than previously thought, according to scientists from The University of Western Australia.

Professor Marco Fiorentini and Professor Steffen Hagemann, from UWA’s School of Earth Sciences, were co-authors of the study published in Proceedings of the National Academy of Sciences.

“The Earth’s largest and most economically significant iron deposits in the Hamersley Range have been dated for the first time and they are up to a billion years younger than previously estimated,” Professor Fiorentini said.

Until now, the scientific community thought iron minerals contained in the Pilbara deposits were formed more than two billion years ago.

“This age was inferred on the basis of analyses that established the formation age of minerals that are spatially associated with iron,” Professor Hagemann said.

“It turns out that those minerals may not be genetically associated with iron.”

Using new state-of-the-art techniques, an international team of researchers directly dated the iron minerals and discovered their mineralisation formed several hundred million years later than previously estimated.

“It looks like these giant ore deposits formed within a geological timeframe that coincided with the breakup and formation of supercontinents,” Professor Fiorentini said.

The new ages proposed in the study for the formation of the largest ore deposits on Earth opens opportunities to establish genetic links between iron and other critical metals that are key to the global energy transition.

The research was done in collaboration with researchers from Curtin University, Rio Tinto and CSIRO Mineral Resources.