Why Do South America and Africa Fit Together Like Puzzle Pieces?
The Two Continents Were Once Connected
by Lucy Benton, age 12
Two-hundred twenty million years ago the world
looked very different. All the continents were joined together into
one big land mass, called Pangea. A huge ocean, Panthalassa,
Two-hundred million years ago, the northern
edge of Australia was connected to the southern edge of Africa.
Today, South America and Africa could still fit together like pieces
of a jigsaw puzzle.
Over millions of years the continents have
moved thousands of miles from their position in Pangea. This movement
is called continental drift.
Even though we don't feel it, the continents
are always moving, this is likely due to the pressure of the hot,
molten rock moving beneath the Earth's surface. The movement of
molten rock through the Earth's interior creates convection currents.
These currents move the land above them at varying speeds. North
America is drifting away from Europe about one inch a year.
Continental drift is a result of a larger
phenomenon called “plate tectonics.” The Earth's surface is
broken into about 20 tectonic plates. Tectonic plates are giant
fragments of the earth's surface. The continents actually sit on top
of the tectonic plates and are carried along when their plate moves.
The movement of these plates, which carry all
of Earth's land masses and bodies of water, is responsible for
earthquakes, volcanoes, mountains, and continental drift. When one
plate crashes into another it can form high mountain ranges. For
example, the Himalayan Mountains were created when India collided
into Asia. The Himalayas are still getting higher today because
India's plate is still pushing into Asia's. To learn more about
tectonic plates, you can read Trinity's article.
The natural world is always changing, thanks
to tectonic plates. In the future the Pacific Ocean is expected to
shrink and the Atlantic Ocean will get wider. Africa may even split
along the Great Rift Valley in the east.
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