What is the focus of an earthquake?
The focus is also called the hypocenter of an earthquake. The vibrating waves travel away from the focus of the earthquake in all directions. The waves can be so powerful they will reach all parts of the Earth and cause it to vibrate like a turning fork.
Epicenter of an earthquake
Directly above the focus on the Earth's surface is the earthquake epicenter . Earthquake waves start at he focus and travel outward in all directions. Earthquake waves do not originate at the epicenter.