The epicenter is the point on the earth’s surface vertically above the hypocenter (or focus), the point in the crust where a seismic rupture begins producing an earthquake.

In the immediate region of the epicenter, the earthquake’s impacts may not be as severe. The epicenter can be found by calculating arcs from three or more seismic observatories, with the arcs’ radii proportional to the time it takes seismic waves to travel from the focus to each station. The epicenter is the location where the arcs intersect.