Georgetown, Australia is quite literally sitting on top of a goldmine of ancient history that sheds light on how Australia and North America were once connected in the supercontinent Nuna over a billion years ago.
Researchers from Curtin University in Perth, Australia found that sediment samples in Georgetown matched deposits in Canada. The study was published in the journal Geology.
It has long been theorized that both Australia and North America were connected as part of a supercontinent, but this new research proves it to be true.
After analyzing sediment samples from Georgetown and Mount Isa in Australia, the researchers were able to show how and when Georgetown broke apart from Nuna.
The results show that Georgetown, Australia broke apart from Nuna 1.6 billion years ago and collided with another landmass to make what is now Australia.
“’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,” said Adam Nordsvan, the study’s lead author. “Georgetown then broke away from North America and collided with the Mount Isa region of northern Australia around 100 million years later.
Supercontinents were common during the Earth’s early years, and the formation and breaking apart of supercontinents is known as the “supercontinent cycle.”
There have been several supercontinents, and Nuna, or as it is sometimes called Columbia, is one of the earliest known in the cycle. Pangea, probably the most well-known and recent of the supercontinents, formed millions of years after Nuna broke apart.
The Curtin researchers are excited about their findings and the implications it could have on future supercontinent research.
“This new finding is a key step in understanding how Earth’s first supercontinent Nuna may have formed, a subject still being pursued by our multidisciplinary team here at Curtin University,” said Zheng-Xiang Li, a co-author of the research.
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By Kay Vandette, Earth.com Staff Writer