Author: HamadyHamady
Date: Aug 17, 2008 08:20
The Earth's crust, the surface on which we daily walk and build our
houses safely, in fact moves on a layer called the mantle which is
denser than the crust. If there was not a system in place to keep this
motion under control, continual shocks and quakes would occur on the
Earth and the world would be a truly unlivable place. And yet, the
mountains and their extensions under the ground greatly decrease
underground movements, and hence such shocks.
The Earth's mountains have come about as a result of movements and
clashes of huge plates which make up the planet's crust. When two of
these plates collide, one usually slides under the other. The plate on
top is pushed up and so forms mountains. At the same time, the plate
at the bottom proceeds under the ground and forms a deep protrusion.
This means that mountains have deep downward protrusions that are as
large as those visible on the surface. In other words, mountains are
firmly rooted in the Earth's layer called the mantle.
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