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Revealed: Four different ways the Earth can look when the next supercontinent forms

Mattias Green, Hannah Sophia Davies and Joao C. Duarte writing for The Conversation

The outer layer of the earth, is made up of broken pieces, much like the shell of a broken egg. These pieces, the tectonic plates, move around the planet at speeds of a few centimeters per year. Every so often they come together and combine into a supercontinent, which remains for a few hundred million years before breaking up. The plates then disperse or scatter and move away from each other until 400-600 million years – come back together again.

The last supercontinent, Pangea, formed around 310 million years ago, and began to break around 180 million years ago. It has been suggested that the next supercontinent will form in 200-250 million years, so we are currently about halfway through the scattered phase of the current supercontinent cycle. The question is: how will the next supercontinent form, and why?

There are four fundamental scenarios for the formation of the next supercontinent: Novopange, Pangea Ultima, Aurica and Amasia. How each form depends on different scenarios but ultimately are linked to how Pangea is separated, and how the world's continents are still moving today.

The breakup of Pangea led to the formation of the Atlantic Ocean, which is still opening and getting wider today. Consequently, the Pacific Ocean is closing and getting narrower. The Pacific is home to a ring of subduction along its edges (the "ring of fire") where ocean floor is brought down, or subducted, under continental plates and into the earth's interior. There, the old ocean floor is recycled and can go into volcanic plumes. The Atlantic, by contrast, has a large ocean ridge producing a new ocean plate, the Lesser Antilles Arc in the Caribbean and the Scotia Arc between South America and Antarctica.

1. Novopangea

If we assume that present day conditions persist, so that the Atlantic continues to open and the Pacific keeps closing, we have a scenario where the next supercontinent forms in the antipodes of Pangea. The Americas would collide with the northward drifting Antarctica, and then into the already collided Africa-Eurasia. The supercontinent that would then form has been named Novopangea, or Novopangaea.

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