Moving continents - Are the continents still moving?

Moving continents - Are the continents still moving?

If you look at a map of the world and the shapes of Africa and South America, you will notice that they seem to fit together.
If you make a jigsaw puzzle of the two shapes, you will see that this is true.
Early in the 20th century, a German scientist called Alfred Wegener studied fossils in rocks from Africa and South America. Fossils are imprints or remains of plants or animals usually found in rocks. He found that the fossils on both continents were the remains of the same animals and plants.
He introduced the theory that mountains in different countries might once have been joined together.
The Cape Mountains in South Africa, for example, could have once been joined to mountains south of Buenos Aires, in Argentina.
Wegener believed that, over millions of years, the continents had gradually moved away from each other.
Continents are still moving today.
Scientists call this movement the continental drift.

Why are the continents moving?

The earth’s crust is made up of a number of enormous separate pieces, called tectonic plates. These plates fit together, like the pieces of a puzzle.
Tectonic plates are all moving, very slowly, in different directions.
Scientists are not sure why these huge, curved sheets of rock move. These solid plates are floating on the mantle, the thick layer of solid rock that also contains hot, liquid rocks moving underneath the earth's crust.

How fast are the tectonic plates moving?

Tectonic plates move from less than one inch (2.5 centimeters) to eight inches (20 centimeters) a year.

How were the continents formed?

As the plates move, they carry the continents and ocean floor with them. Tectonic plates have been moving for billions of years.  More than two hundred million years ago the earth’s dry land was all bunched together, forming one gigantic continent. Slowly, as the plates moved, the one huge continent broke into two continents.
And, as the plates continued to move, both of these continents broke up to form the seven continents we know today.
As the plates keep moving, the continents and seas are still changing shape. Millions years from now, the continents will be even farther apart than they are now.
The ocean will become wider and Australia may move up and push against Southeast Asia, becoming part of it.
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