B. Plate boundaries

Before we look at why the plates moved, we should first take a look at the different types of plates and different types of plate boundaries.

 

Plates

There are two types of plates, oceanic and continental.

 

Types of Plate boundaries

-Constructive (divergent) plate boundaries

Constructive plate boundaries move apart from each other. Shield volcanoes are found at constructive plate boundaries and a very good example of constructive plate boundaries is at the Mid-Atlantic Ridge where the North American plate is moving apart from the Eurasian plate.

 

-Destructive (convergent) plate boundaries

Destructive plate boundaries are found at boundaries of oceanic and continental plates overlapping each other. Since the oceanic plate is heavier, it sinks under the continental plate with the continental plate going up to build up Stratovolcanoes. Mount St. Helens in Washington, Mount Pinatubo in the Philippines and Mount Fuji in Japan are all found at destructive plate boundaries.

 

-Collision plate boundaries

Collision plate boundaries are found when two continental plates move towards each other to build up mountains. Earthquakes are found at collision plate boundaries. The Himalayas, Appalachian Mountains in the USA are all good examples of the mountains formed at collision plate boundaries.

 

-Conservative (transform) plate boundaries

Conservative plate boundaries slide past each other, earthquakes are found at those boundaries due to the pressure built from sliding past. The San Andreas Fault is a very good example of conservative plate boundary.

 

Done