It is known that actual continents were forming, billions of years ago, only one huge continent. New findings tend to prove that theory as scientists discovered evidence that Australia was once a part of North America.
Speculations date back to the 70s
The theories that Australian and North American continents have split up from one single continent with billions of years ago have emerged in the 70s. Back then, C.W. Jefferson at the Geological Association of Canada emitted the theory that Australian and North American continents were once part of the same supercontinent, called Rodinia.
Rodinia has formed 1 billion years ago, supposedly, and started to divide 750 million years ago into three distinct continents. Later on, these three parts have reconnected with each other during the Pan-African orogenesis movements that lasted for 60 million years, forming once again a supercontinent that scientists called Pannotia.
Afterwards, Pannotia divided into several continents among which the most important were Laurentia from which North America will be formed, Baltica from which North Europe will be formed, and Siberia.
The pieces of evidence
Researchers have observed that some rocks in Georgetown, a small village in northeast Australia, are not similar to any other rock on Australian territory. Surprisingly, the rocks are similar to those that form the so-called Canadian Shield which is a part of the continental crust that is visible in Canada.
According to the geologists at the Monash University, the Geological Survey of Queensland, and the Curtin University these recent discoveries show a lot of information about the prehistoric supercontinent Columbia, also known as Nuna.
Adam Nordsvan, Ph.D. at Curtin University thinks that this recent discovery shows that Australia, as it is today, was formed by the collision of the part that contains Georgetown and Mount Isa in north Australia with more than 100 million years ago.
Researchers concluded that their findings that Australia was part of North America are an important step towards understanding how the Earth’s first supercontinents formed.