Where and why earthquakes happen?

Then the scientific world has not taken a bold hypothesis in the rightness of our time, Wagner's assumptions no longer in doubt. With the help of modern instruments, scientists have proved that the earth's crust consists of about 20 plates of different sizes. The thickness of these tectonic plates Earth's crust ranges from 60 to 100 kilometers. Earthquakes often occur in places where these plates in contact with one another. Scientists have divided the space on the belt. The first belt surrounds the Pacific Ocean and runs along the edge of a huge basalt slab that covers the entire bottom of the ocean. The second zone begins in the middle of the Atlantic Ocean and passing through the Mediterranean basin, Himalayan mountain range, Asia, and reaches the Pacific Ocean. This zone consists of several tectonic plates and is called Sredizemnotransaziatsky. Third, the Atlantic zone, captures Atlantic ridge, Iceland and comes to Antarctica. This zone consists of several tectonic plates. Earthquakes occur most frequently in close proximity to high mountains or deep ocean basins. Most of all taking place on our planet earthquake - Tectonic. They are associated with the processes of transformation of the planet. There are still so-called "volcanic" earthquakes. They arise from the fact that the lava and hot gases swirling in the depths of volcanoes, can put pressure on the upper layers of the Earth, as a pair of boiling water on the lid. But such earthquakes less destructive than tectonic well as vibration and shocks while they are not as powerful and sharp as when tectonic shifts in the earth's crust. Volcanic earthquakes continued for much longer than the tectonic: a week or even month. Earth tremors can be caused by landslides. So there are local landslide earthquake.