One is the circum-Pacific belt which encircles the Pacific Ocean, and the other is the Alpide belt which slices through Europe and Asia. The circum-Pacific belt includes the West coasts of North America and South America, Japan, and the Phillipines. Over one million earthquakes may occur each year on the Earth. Most earthquakes last only seconds, but some large quakes may last minutes. When these plates move suddenly they release an incredible amount of energy that is changed into wave movement.
Earthquake waves resemble sound and water waves in the manor in which they move.
It is these waves that roll through the Earth's crust causing buildings to collapse, bridges to snap, mountains to rise, the ground to fall, and in some cases the ground to open up into huge cracks.