Earthquakes are caused by movements of tectonic plates. Explain the phenomenon. Describe seismic zone, seismic focus and epicentre w.r.t the earth's plates. Draw a neat diagram to show locations of focus and epicenter. What other reasons can also cause earthquakes?

The reason so many earthquakes occur in these areas is because this is where many of Earth's tectonic plates come together. Earthquakes begin deep underground along plate boundaries. Tension and pressure build up as the plates slide past and bump into each other and sometimes even stick together. Although the plate boundaries themselves may be stuck, the plates keep moving and pulling. Eventually, the pulling becomes too much and the plates suddenly break free from each other, causing an earthquake.
 

A seismic zone is a region in which the rate of seismic activity remains fairly. consistent. This may mean that seismic activity is incredibly rare, or that it is. extremely common.

The focus of an earthquake is the point where the rocks start to fracture. It is the origin of the earthquake. The epicenter is the point on land directly above the focus.

Volcanic Earthquakes​ - Compared to tectonic earthquakes, volcanic earthquakes are less prevalent. They typically take place before or after an eruption.
 Explosion Earthquakes​ -  These are caused by nuclear explosions.
 Collapse Earthquakes​ -These kinds of earthquakes are generally smaller and most commonly occur near underground mines. 

Regards