TSUNAMI

TSUNAMI

Tsunami comes from the word Tsu and Nami = Port = Wave. Being part of the world languages, after the big earthquake June 15, 1896, which caused a large tsunami struck the port city of Sanriku (Japan) and killed 22,000 people and damage to beaches along 280 km east of Honshu.

The most common cause is an undersea earthquake. An earthquake that is too small to create a tsunami by itself may trigger an undersea landslide quite capable of generating a tsunami. Tsunamis can be generated when the sea floor abruptly deforms and vertically displaces the overlying water. Such large vertical movements of the earth's crust can occur at plate boundaries. Sub-marine landslides; which are sometimes triggered by large earthquakes; as well as collapses of volcanic edifices, may also disturb the overlying water column as sediments and are redistributed across the sea floor. Similarly, a violent submarine volcanic eruption can uplift the water column and form a tsunami. Although often referred to as 'tidal waves', a tsunami does not look like the popular impression of normal wave only much bigger. In addition, the tsunami caused by long-period ocean waves generated by impulsive disturbances undersea.