Earthquakes and Volcanoes

A giant slab of rock taht floats on the mantle that makes up the earth's surface.

Two plates move apart. Molten rock fills the gap. That's why they're constructive. example. mid ocean ridge in Atlantic ocean.

• Also known as destructive plate maargin. Two plates collide and the densser oceanic plate sinks. the other one is continental.
• The descending plate is heated from the interior's magma from the friction and increasing pressure.
• Newly formed magma is less dense thatn the surrounding material and so rises through pressure along vents to surface where it is intruded into the crust or breads through the surface.

Two plates of same weight and density collide. They are squeezed upwards and form fold mountains like the Himalayas.

Two plates slide past each other. They are parallel to each other (lateral movement).Great build up of friction creates great earthquakes like in California between Pacific and North American Plates.