Plate Margin (platentectoniek)

PLATE MARGIN
There are four types of plate margins. The first is the constructive margin. This is a process where the seafloor is spreading and new oceanic crust is being created, there arise new volcanic islands, a good example is Iceland. It also causes earthquakes. A good example of this kind of plate margin is the Mid-Atlantic ridge.

The new crust is being created when the magma from the mantle is pushed up underneath the Earth's surface. This magma, or rather lava, hardens when it comes into contact with the water. Then it forms the new oceanic crust.

The second is the destructive margin, a process where the oceanic crust is subducted and destroyed beneath heavier continental crust. This effects mountains, earthquakes and volcanoes and a deep sea trench. You can find this process all along the West Coast of South America. The Andes Mountains for example.

The third process is the collision margin. Here two continental plates are colliding. There is no new crust being created but therefor this type of margin creates high mountains, a prime example is the Himalayas, this mountains were created when India bumped into Asia. It also causes earthquakes.

The last kind of plate margin is the conservative margin. Here two plates are moving past each other. There is no destruction, construction or volcanoes created but instead of that there are really heavy earthquakes.These are for example in Los Angeles and California. In California extends the amply 13000 km long San Andreas Fault.