This is a drawing of a process which forms mountains on Earth.
Click on image for full size

Mountain Building by way of Subduction

Mountains are built through a general process called "deformation" of the crust of the Earth. Deformation is a fancy word which could also mean "folding". An example of this kind of folding comes from the process described below.

When two sections of the Earth's crust collide, rather than being forced down to deeper regions of the Earth, the slabs of rock can pile into each other head on, causing one or both slabs to fold up like an accordion.

This process causes the crust to be

  • 1.) raised, and
  • 2.) folded up.
In the end, a mountain range is produced.

This process is illustrated in the figure to the left. A slab of the Earth's crust, on the right is forced to go down, while the slab on the left is forced to fold up. The slab on the right might eventually melt and form a volcano.


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