Earthquakes: An earthquake is the result of a sudden release of energy in the Earth's crust that creates seismic waves.
Elastic Rebound: geology a theory of earthquakes that envisages gradual deformation of the fault zone without fault slippage until friction is overcome, when the fault suddenly slips to produce the earthquake
Focus: The hypocenter refers to the site of an earthquake or a nuclear explosion. In the former, it is a synonym of the focus; in the latter, of ground zero.
Epicenter: The epicenter is directly above the earthquake's focus (hypocenter). In the case of earthquakes, the epicenter is directly above the point where the fault begins to rupture, and in most cases, it is the area of greatest damage.
Seismology: the branch of science concerned with earthquakes and related phenomena.
Seismometer: Seismometers are instruments that measure motions of the ground, including those of seismic waves generated by earthquakes, volcanic eruptions
Magnitude: logarithm of the ratio of the amplitude of waves measured by a seismograph to an arbitrary small amplitude.
Intensity: the measurable amount of a property, such as force, brightness, or a magnetic field.
Tsunami: a long high sea wave caused by an earthquake, submarine landslide, or other disturbance.
Seismic gap: is a segment of an active fault known to produce significant earthquakes, that has not slipped in an unusually long time when compared with other segments along the same structure.