Focus and epicentre

The point inside the crust where the pressure is released is called the focus.

The point on the Earth's surface above the focus is called the epicentre.

Earthquake energy is released in seismic waves. These waves spread out from the focus.

The waves are felt most strongly at the epicentre, becoming less strong as they travel further away.

The most severe damage caused by an earthquake will happen close to the epicentre.

Earthquakes Cross section