Two hundred and fifty million years ago the Earth was one supercontinent named Pangaea. Let's jump 250 million years in the future: it will be one piece of land again, just with a different name - Pangaea Ultima.
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Million years from now Africa will smash into Europe and Australia will migrate north to merge with Asia. The Atlantic Ocean will widen for, then it will reverse the course disappears. The surface of the Earth is composed of large pieces - plates - that are slowly shifting. That is called "plate tectonics." Using geological clues to puzzle out past migrations of the continents, Dr. Christopher Scotese, a geologist at the University of Texas at Arlington, has made an educated guess of how the continents are going to move hundreds of millions of years into the future.
"We can make predictions of how plate motions will continue, what new things might happen, and where it will all end up." Among those predictions: Africa is likely to continue its northern migration, pinching the Mediterranean closed and driving up a Himalayan-scale mountain range in southern Europe. Just look at the Mediterranean region today. Africa has been slowly colliding with Europe for millions of years, Scotese said. Italy, Greece and almost everything in the Mediterranean is part of the African plate, and it has been colliding with Europe for the last 40 million years.
That collision has pushed up the Alps and the Pyrenees mountains, and is responsible for earthquakes that occasionally strike Greece and Turkey. The Mediterranean is the remnant of a much larger ocean that has closed over the last 100 million years, and it will continue to close. More and more of the plate is going to get crumpled and get pushed higher and higher up, like the Himalayas.
Australia is moving north, and is already colliding with the southern islands of Southeast Asia. If we project that motion, the left shoulder of Australia gets caught, and then Australia rotates and collides against Borneo and south China - sort of like India collided 50 million years ago - and gets added to Asia.
Meanwhile, the Americas will be moving further away from Africa and Europe as the Atlantic Ocean steadily grows. The Atlantic sea floor is split from north to south by an underwater mountain ridge where new rock material flows up from Earth's interior. The two halves of the sea floor slowly spread apart as the ridge is filled with the new material, causing the Atlantic to widen. In the case of the widening Atlantic, geologists think that a "subduction zone" will eventually form on either the east or west edges of the ocean.
At a subduction zone, the ocean floor dives under the edge of a continent and down into the interior of the Earth. "As it sinks, it pulls the rest of the plate with it. This accounts for most of the force that moves the plates around," Scotese said.
Tens of millions of years later, the Americas would come smashing into the merged Euro-African continent, pushing up a new ridge of Himalayan-like mountains along the boundary. At that point, most of the world's landmass would be joined into a super-continent called Pangaea Ultima. That will be the end of the long journey for the Earth: from Pangaea to Pangaea Ultima. ■