The earthquakes are a natural hazard which is associated with boundaries of the tectonic plates. The majority of the earthquakes occur at convergent and transforming plate boundaries. The reason as to why the earthquakes occur at these places is because of the pressure between the colliding or sliding plates, where the crust cracks and during the adjustment the force created is manifested with strong vibrations.
In general, the earthquakes occur at depths between 20 and 50 km, which is usually the depth where the plates create the most pressure upon each other. That is not to say that that is the only range where earthquakes occur, as they can occur anywhere from the surface of Earth and down to 800 km in depth. With other words, the earthquakes occur anywhere from the top of the lithosphere to the top of the astenosphere. Earthquake hot-spots are:
