Melbourne: Researchers have discovered rocks in Queensland that bear striking similarities to those found in North America, suggesting that a chunk of Australia was actually part of America 1.7 billion years ago.
The research published in the journal Geology found that the rocks have signatures that are unknown in Australia and instead have a surprising resemblance to those found in Canada today.
According to Adam Nordsvan, a PhD student at Curtin University in Australia, the findings are significant as they unlock important information about the 1.6 billion-year-old super-continent 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 Mount Isa region of northern Australia around 100 million years later," Nordsvan said.
This was a critical part of global continental reorganisation when almost all continents on Earth assembled to form the super-continent called Nuna, researchers said.
The team was able to determine this by using both new sedimentological field data and new and existing geochronological data from both Georgetown and Mount Isa.
Researchers then determined that when the supercontinent Nuna broke apart an estimated 300 million years later, the Georgetown area did not drift away and instead became a new piece of real estate permanently stuck to Australia.
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, said Zheng- Xiang Li, also from Curtin.