Georgetown, Australia is quite literally sitting on top of a goldmine of ancient history. The town 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.
Supercontinents are massive landmasses that have existed throughout Earth’s history. These landmasses are formed when several smaller continents collide and merge together. This results in a single, large landmass. The most well-known supercontinent is Pangaea, which existed around 300 million years ago during the late Paleozoic and early Mesozoic eras.
Pangaea was formed through the collision and merging of several smaller continents. This includes North America, South America, Africa, Europe, and Asia. The supercontinent was surrounded by a single, massive ocean called Panthalassa. The formation of Pangaea had a significant impact on the planet’s climate and the evolution of life on Earth.
As Pangaea broke apart, it created the modern continents that we see today. This process is known as continental drift. It occurs as a result of tectonic plate movements. The theory of plate tectonics explains how the Earth’s crust is divided into several plates. These plates are in constant motion, causing the continents to move and shift over time.
Supercontinents are not a rare phenomenon in Earth’s history. In fact, scientists have identified several supercontinents that existed before Pangaea. These include Rodinia, which existed around one billion years ago, and Gondwana, which existed around 500 million years ago.
The study of supercontinents is important because it helps us understand the evolution of the Earth’s crust, the movements of tectonic plates, and the changes in climate and biodiversity that have occurred throughout history. By studying supercontinents, scientists can also make predictions about the future of the planet and the potential formation of new supercontinents.
In summary, supercontinents are a fascinating topic of study for geologists and scientists alike. They represent a unique phase in the Earth’s history. They also provide valuable insights into the planet’s geological and biological evolution. As we continue to study supercontinents, we can deepen our understanding of the Earth’s past and potentially even predict its future.
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By Kay Vandette, Earth.com Staff Writer