Earthquake:a sudden and violent shaking of the ground, sometimes causing great destruction, as a result of movements within the earth's crust or volcanic action.
Elastic Rebound:The elastic rebound theory is an explanation for how energy is spread during earthquakes. As rocks on opposite sides of a fault are subjected to force and shift, they accumulate energy and slowly deform until their internal strength is exceeded.
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 point on the earth's surface vertically above the focus of an earthquake.the central point of something, typically a difficult or unpleasant situation.
Seimology: the branch of science concerned with earthquakes and related phenomena.
Seismograph: an instrument that measures and records details of earthquakes, such as force and duration.
Magnitude:Magnitude is the logarithmic measure of the brightness of an object, in astronomy, measured in a specific wavelength or pass band, usually in optical or near-infrared wavelengths.
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: A 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.