2 types of plates.
Continental plates - under land.
Oceanic plates - under ocean.
3 types of plate movements
Separating plates - drag apart.
Colliding plates - pushed together
Sliding plates - slide past each other.
Separating plates.
As the two plates separate, magma rises up through the gaps.It then cools down becomes solid and forms new crust. Example - the Mid Atlantic Ridge.
Colliding plates
When plates collide , the crust is destroyed.When oceanic plates ( heavier) and a continental plate ( lighter) collide , the heavier oceanic plates is forced down into the hot mantle below and melts the lighter continental plates Buckles upwards. Example - Nazca and Sout American plates.
Sliding plates
As the plates slide past each other , they can become locked together. As pressure is released causing an earthquake. Example - the San Andrea's Fault, California.