The epicenter, epicentre (/ˈɛpɪsɛntər/) or epicentrum in seismology is the point on the Earth's surface directly above a hypocenter or focus, the point where an earthquake or an underground explosion originates.
The focus is the place inside Earth's crust where an earthquake originates. The point on the Earth's surface directly above the focus is the epicenter. When energy is released at the focus, seismic waves travel outward from that point in all directions.
