The Mid-Atlantic Ridge – a range of (underwater) submarine mountains and volcanoes
Magma rises through fissures
Where the ridge rises above sea level, islands such as Iceland are formed
Volcanic vent
Earth's crust
(oceanic)
North American Plate moves west
Eurasian Plate moves east Convection currents drive the plates apart Mantle 4. The Mid-Atlantic Ridge
At Destructive Plate Boundaries At destructive boundaries, plates are colliding with each other.
When an oceanic plate collides with a continental plate, the heavier oceanic plate is forced down into the mantle below. The oceanic plate begins to melt.
As it melts, magma can rise up to the surface through cracks in the crust above.
The magma will continue to erupt and a volcanic mountain can form at the surface.
Mount Saint Helens in the US is an example of this.
To watch a video that explains volcanic eruptions at destructive plate boundaries, go to YouTube and search for ‘Explaining Destructive Plate Boundaries – GCSE’ (play from 0:00 to 1:29 sec).