Coming to a continent near you: America

Also Asia, Europe and Africa

It's going to be a heck of a reunion: the Pangea supercontinent that broke up to create the atlas we know today will one day reform in the Northern hemisphere.

That's the conclusion reached [1] by researchers at Yale University who, instead of looking at the past history of continental movements, have turned their attention to the future.

It's a difficult prediction to test, however: their estimate of the time it's going to take for today's continents to collide with each other and form what they call "Amasia" is around a hundred million years (with a pretty big error bar – somewhere between 50 million and 200 million).

Their work, published in Nature [2], proposes a process called orthoversion, in which new supercontinents form 90 degrees from the geographic centre of their ancient predecessors. If they're correct, the Arctic Ocean and Caribbean Sea of today's Earth will disappear, pushed aside as North and South America migrate northwards, fuse, and collide with Europe and Asia.

Alaska and the Asian end of Russia will get friendly again – goodbye to the Bering Strait. Australia and India, separated a long time in the past, will tuck up underneath today's Asian continent, with Africa likely to turn the Mediterranean into a narrows rather than a sea.

The researchers, led by Yale doctoral student Ross Mitchell, places the Americas and Eurasia more-or-less at the North Pole when the new supercontinent forms.

The new theory contradicts current models of supercontinent formation, which suggests that new supercontinents form either at 0 or 180 degrees to their predecessors (referred to as introversion or extroversion). These theories suggest the new supercontinent would form either by today's continents squeezing out the Atlantic Ocean or the Pacific.

Their prediction is based on the magnetism of ancient rocks, which suggests supercontinents underwent "a series of back-and-forth rotations around a stable axis along the equator". These axes were offset not by the 0 or 180 degrees proposed in prior theories, but by 90 degrees.

Mitchell's orthoversion model suggests that the new supercontinent will be centred around either Asia or North America, in a spot now occupied by the Arctic Ocean, and stitched together by a new mountain range.

Links
<http://news.yale.edu/2012/02/08/next-supercontinent-forms-arctic-ocean-caribbean-will-vanish-first>
http://www.nature.com/nature/