Earthquake | Definition, Causes, Effects, & Facts | Britannica
Jan 14, 2025 · Earthquake, any sudden shaking of the ground caused by the passage of seismic waves through Earth’s rocks. Earthquakes occur most often along geologic faults, narrow zones where rock masses move in relation to one another.
earthquake - Kids | Britannica Kids | Homework Help
In an earthquake, huge masses of rock move beneath Earth’s surface and cause the ground to shake. Earthquakes occur constantly around the world. Often they are too small for people to feel at all, but some earthquakes are massive. They can cause great destruction.
Earthquake - Magnitude, Intensity, Effects | Britannica
5 days ago · Earthquake - Magnitude, Intensity, Effects: The violence of seismic shaking varies considerably over a single affected area. Because the entire range of observed effects is not capable of simple quantitative definition, the strength of the shaking is commonly estimated by reference to intensity scales that describe the effects in qualitative terms.
earthquake - Students | Britannica Kids | Homework Help
The sudden shaking of the ground that occurs when masses of rock change position below Earth’s surface is called an earthquake. The shifting masses send out shock waves that…
Earthquake - Magnitude, Seismology, Epicenter | Britannica
5 days ago · Earthquake - Magnitude, Seismology, Epicenter: Earthquake magnitude is a measure of the “size,” or amplitude, of the seismic waves generated by an earthquake source and recorded by seismographs. (The types and nature of these waves are described in the section Seismic waves.)
Earthquake - Tectonics, Seismology, Faults | Britannica
6 days ago · Earthquake - Tectonics, Seismology, Faults: Tectonic earthquakes are explained by the so-called elastic rebound theory, formulated by the American geologist Harry Fielding Reid after the San Andreas Fault ruptured in 1906, generating the great San Francisco earthquake.
Seismic wave | Earth’s Interior Structure & Movement | Britannica
Dec 28, 2024 · Seismic wave, vibration generated by an earthquake, explosion, or similar energetic source and propagated within the Earth or along its surface. Earthquakes generate four principal types of elastic waves; two, known as body waves, travel within the Earth, whereas the other two, called surface
Earthquake - Seismology, Epicenters, Magnitude | Britannica
5 days ago · Many reports of unusual lights in the sky and abnormal animal behaviour preceding earthquakes are known to seismologists, mostly in anecdotal form. Both these phenomena are usually explained in terms of a release of gases prior to earthquakes and electric and acoustic stimuli of various types.
2010 Haiti earthquake | Magnitude, Damage, Map, & Facts
Jan 15, 2010 · 2010 Haiti earthquake, large-scale earthquake that occurred January 12, 2010, on the West Indian island of Hispaniola, comprising the countries of Haiti and the Dominican Republic. Most severely affected was Haiti, occupying the western third of the island .
Earthquake - Shallow, Intermediate, Deep Foci | Britannica
5 days ago · Earthquake - Shallow, Intermediate, Deep Foci: Most parts of the world experience at least occasional shallow earthquakes—those that originate within 60 km (40 miles) of the Earth’s outer surface. In fact, the great majority of earthquake foci are shallow.