NORTHERN Australia was actually part of North America 1.7 billion years ago, new research by Curtin University suggests.
The researchers found rocks 412km west of Cairns in Georgetown that are unknown in Australia and have a surprising resemblance to rocks found in Canada today.
The research paper was released in Geology, which is published by the Geological Society of America.
Curtin University PhD student Adam Nordsvan, from the university’s School of Earth and Planetary Sciences, said the findings were significant as they unlocked important information about the 1.6 billion year old supercontinent Nuna.
“Our research shows that about 1.7 billion years ago, Georgetown rocks were deposited into a shallow sea when the region was part of North America. Georgetown then broke away from North America and collided with the Mt Isa region of northern Australia around 100 million years later,” Mr Nordsvan said.
“This was a critical part of global continental reorganisation when almost all continents on Earth assembled to form the supercontinent called Nuna.”
The team used new and existing data from both Georgetown and Mt Isa.
They then determined that when the supercontinent Nuna broke apart about 300 million years later, the Georgetown area did not drift away but stayed stuck to Australia.
Research paper co-author Professor Zheng-Xiang Li said the research also revealed new evidence of mountains being built in both the Georgetown region and Mt Isa when Georgetown collided with the rest of Australia, but that the collision was not hard.
The research was co-|authored by researchers from Curtin University, Monash University and the Geological Survey of Queensland.