Researchers have predicted that a new megacontinent, Amasia, will form in the next 250 million years.
The enormous plates of the earth’s crust have drifted together and apart over hundreds and millions of years. These variations, known as “true polar wander”, are caused by changes in the planet’s mass distribution. They are the Earth’s attempt to maintain rotational equilibrium.
The research is based on a theory called Orthoversion, according to which, after a supercontinent breaks up, the continents initially drift apart but become trapped within a north–south band of subduction where one plate dips below another.
Published in the journal Nature, the research has also been supported by a paper published in the journal Geology by Dr Masaki Yoshida, a geologist based at Japan’s Agency for Marine–Earth Science and Technology (JAMSTEC).
Using records of the Earth’s magnetic field preserved in rocks, the researchers studied variations in the rotation of the Earth with respect to its spin axis to test the model. After combining this data with the knowledge of how supercontinents affect the Earth’s motion, researchers were able to predict what they called ‘Amasia.’
The new supercontinent will form on our present-day Earth’s Pacific Ring of Fire. “After those water bodies close, we’re on our way to the next supercontinent,” said Dr Ross Mitchell, the paper’s lead author. “You’d have the Americas meeting Eurasia practically at the North Pole.”
The most recent supercontinent, Pangea (Greek for ‘All Lands’), was formed about 300 million years ago with Africa at its centre. It began breaking apart into the seven continents of today with the birth of the Atlantic Ocean about 100 million years later. Its immediate predecessors were Rodinia – which formed about 1 billion years ago – and Nuna, which formed about 1.8 billion years ago.
Courtesy: Mail Online