There are two types of plates, the continental and the oceanic.
Made up of mostly granite
Is about 18 to 25 miles thick
It contains the land mass
These plates are less dense
Made up of mostly basalt
Is about 3 to 6 miles thick
The layer holds the oceans
These are more dense than continental plates
The plates are believed to move by hot air currents under the surface
Some people also believe that the earth's rotation moves it.
Since the plates move, there are bound to be crashes
There are several types being...
Ocean to Continent
- Continent to Continent
This is what builds mountains. They have the same density so they don't sink or float on each other.
When this happens the oceanic layer slips under the continental layer and remelts. The continental layer just stays on top covering the oceanic layer.
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