A TSUNAMI (of the Japanese TSU: port or bay, NAMI: wave) is a wave or series of waves that take place in a mass of water to the being pushed violently by a force moves that it vertically. This term was adopted in a 1963 congress.
Coastal or underground earthquakes, volcanos, meteorites, landslides and explosions of great magnitude even can generate aTSUNAMI.
Formerly it was called “swells to them”, “tidal waves” or “marine seismic waves”, but these terms have been being obsolete, since they do not describe the phenomenon suitably. Both first they imply tide movements, that it is a different phenomenon and that has to do with desbalance oceanic caused by the gravitational attraction exerted by planets, the sun and especially the moon. Theseismic waves, on the other hand, imply an earthquake and we already saw that there are several other causes of a TSUNAMI.
Tsunami is not felt generally by the ships on the high seas (the waves on the high seas are small) nor can visualize from the height of an airplane flying on the sea.
As it can assume, tsunamis can at a distance be caused by local earthquakes or happenedearthquakes. Of both, first they are those that produce more devastating damages because it is not reached to tell in good time to evacuate the zone (they take place generally between 10 and 20 minutes after the earthquake) and to that the earthquake by itself generates terror and chaos that do very difficult to organize an evacuation ordinate.
As it werementioned in the previous point, the Earthquakes are the great cause of tsunamis. So that an earthquake originates tsunami the marine bottom must steeply be moved in vertical sense, so that the ocean is driven outside its normal balance. When this immense mass of water tries to restore its balance, the waves are generated. The size of tsunami will be determined by the magnitude of the verticaldeformation of the marine bottom. All the earthquakes do not generate tsunamis, but only those of considerable magnitude, that happen under I milk marine and which they are able to deform it.
Although any ocean can experience tsunami, it is more frequent than they happen in the Pacific Ocean, whose margins are more commonly earthquake seat of considerable magnitudes (especially the coastsof Chile and Peru and Japan). In addition the type to fault that happens between the plates of Is born and South American woman, call of subduction, this are that a plate is slid under the other, make the deformity of the marine bottom and therefore tsunamis more propitious.
In spite of what has been said previously, they have reported tsunamis devastating in the Atlantic Oceans and Iindicate, as well as the Mediterranean Sea. Great tsunami accompanied earthquakes by Lisbon in 1755, the one of the Passage of Pretty of Puerto Rico in 1918, and ee of Grand Banks of Canada in 1929.
The volcanic avalanches, eruptions and underwater bursts can cause tsunamis that usually dissipate quickly, without reaching to bring about damages in their continental margins.With respect to meteorites, there are no reliable antecedents about his occurrence, but the rarefaction wave that would at heart cause when entering the ocean or the impact sailor in case of falling in zone of low depth, are quite viable factors like thinking about them like possible cause of tsunami, especially if one is a meteorite of great size.
WHAT IS THE DIFFERENCE AND SO WE CALLED“SWELLS”?
The swells take place habitually by the action of the wind on the surface of the water and their waves have a ritmicidad that usually is of 20 seconds and at the most 150 meters usually propagate inland about, as we observed in the weathers or hurricanes. In fact the propagation is limited by the distance, so that it is losing intensity when moving away to us of the place...