Earth is the only planet in our solar system where the process of plate tectonics occurs," said Professor Patrice Rey, from the University of Sydney's School of Geosciences.
"The geological record suggests that until three billion years ago the Earth's crust was immobile so what sparked this unique phenomenon has fascinated geoscientists for decades. We suggest it was triggered by the spreading of early continents then eventually became a self-sustaining process."
Professor Rey is lead author of an article on the findings published in Nature on Wednesday, 17 September.
The other authors on the paper are Nicolas Flament, also from the School of Geosciences and Nicolas Coltice, from the University of Lyon.