La princesa

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Earthquakes

The earthquakes take place when the bark of the Earth moves suddenly along a flaw. The subjected rock to a great pressure breaks and it liberatesenergy in form of seismic waves. Most of the earthquakes are so low magnitude that the human beings don't detect them. Some earthquakes produce similar vibrations to those created by the step of a heavytruck.

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Types and locations of the earthquakes

The scientistsdistinguish three big types of earthquakes: tectonic, volcanic and the provoked ones for human activities.

The earthquakes of tectonic origin outside of the Cinturón de Fuego are located alongcontact areas among badges in numerous points of the Earth. The human beings rarely perceive these earthquakes. Theseearthquakes only represent 5% of the seismic energy of the Earth

The origin earthquakes volcanic few times they reach big magnitudes. Their interest resides mainly in that they announce imminent volcaniceruptions, like it happened during the previous weeks to the eruption of the Mount St. Helens in the northwest of the United States in 1980.

The human beings can cause or to increase theappearance of earthquakes by means of certain activities like to add a bigger load of water to a reservoir. The human beings can cause or to increase the appearance of earthquakes by means of certainactivities like to add a bigger load of water to a reservoir.

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National Earthquake Information Center - NEIC

The mission of the NationalEarthquake Information Center is to determine rapidly the location and size of all destructive earthquakes worldwide and to immediately disseminate this information to concerned national and international...