The drift of the continents is a scientific fact that has been proven for decades. However, new evidence of the movements of the continents in the past is still surprising today, an exciting journey of the great terrestrial plates to configure the appearance that our planet has today.
Researchers at Curtin University have come up with clues suggesting that part of northern Australia was actually part of North America 1.7 billion years ago – a collection of rocks found in northern Queensland, Australia, that have striking similarities. with those found in North America.
The work concluded that the rocks found at 412 kilometers west of Cairns, have signatures that are unknown in Australia and instead bear a striking resemblance to the rocks found in Canada.
Nuna, the first supercontinent
The findings shed light on important information about the 1.7 billion-year-old supercontinent Nuna.
“About 1.7 billion years ago, the Georgetown rocks were deposited in shallow water when the region was part of North America. Georgetown broke away from North America and collided with the Mount Isa region of northern Australia about 100 millions of years later, “as detailed in the research, published by the Geological Society of America.
This was a critical part of the global continental reorganization when almost all the continents on Earth came together to form the supercontinent called Nuna.
In addition, the team has been able to determine that when the supercontinent Nuna broke apart some 300 million years later, the Georgetown area did not disappear and instead became permanently trapped in Australia.
The investigation also revealed new evidence of mountains in the Georgetown region when it collided with the rest of Australia.
Specifically, the research shows that this mountain belt, in contrast to the Himalayas, would not have been very high, suggesting the final continental assembly process that led to the formation of the supercontinent Nuna was not a hard collision like the recent collision of India with Asia.
This finding is a key step in understanding how Earth’s first supercontinent formed. Nuna, also known as Columbia, Hudsonland or Hudsonia, is the oldest supercontinent formed on Earth.
Estimates put Nuna to be about 12,900 kilometers from north to south, and about 4,800 kilometers wide.
References: Adam R. Nordsvan et al. Laurentian crust in northeast Australia: Implications for the assembly of the supercontinent Nuna, Geology (2018). DOI: 10.1130 / G39980.1
