Newly Analyzed Zircon Crystals Hint at Tectonic Activity on Early Earth
An international research team led by Nanjing University, with co-author Professor Tony Kemp from The University of Western Australia, has analyzed zircon crystals from granitic rocks in the Pilbara Craton, Western Australia.
The study, published in Science Advances, found that magmas forming the granites became more oxidized and water-rich between 3.5 and 3.2 billion years ago.
The findings suggest that subduction—where tectonic plates converge and one sinks beneath another—could have been active on early Earth, transporting water into the deep crust and mantle. This process is currently responsible for continental crust formation.
The researchers propose that an early form of plate subduction existed 3.5 billion years ago, contributing to ancient continent growth.