The causes of tsunamis or tidal waves are tectonic movements or natural phenomena such as avalanches due to volcanic eruptions or meteorite impacts, which move large masses of water producing waves several meters high.
Tsunamis have been found to be caused in 90 percent of cases by large-scale earthquakes or earthquakes.
The large waves that are produced in the sea by these disturbances not only take on enormous dimensions, but also travel so fast that they contain enormous energy that causes serious damage when impacting the coasts.
Main causes of tsunamis
Certain conditions must be met for a tsunami to be generated, it is not enough just to have a telluric movement or a particular natural phenomenon.
Generally, the geographical shape of the area in which the incident occurs will be decisive.
Earthquakes
The earthquakes that cause tsunamis are those that occur at the bottom of the ocean floor in a vertical direction.
This causes the waves to begin to move in the form of concentric rings in different directions.
Other factors that influence the formation or not of a tsunami due to earthquakes are the depth of the epicenter and whether it was distant, close or local.
According to the studies, those that cause the most damage are those nearby and local, due to the short time that elapses between the movement and the arrival of the first wave to the coast.
The coasts of Japan and Chile in the Pacific Ocean are among those that are most affected by Tsunamis. The tectonic plates in that area are in constant friction accumulating tension from being located in The Ring of Fire.
These regions use alarm systems to warn their inhabitants about possible tsunamis and have an important educational plan so that the population knows how to respond in case of emergency or evacuation of threatened areas.
Despite the fact that Indonesia is not listed as a high-risk zone for receiving tsunamis, the worst tragedy in history was caused by an earthquake in the Indian Ocean in 2004.
This confirms that there is no definitive formula for knowing where a tsunami earthquake can occur.
Tsunamis due to non-tectonic causes
Landslides from volcanic activity or even meteorite impacts can generate enough tidal movement to produce a tsunami.
Although by statistics this represents only 10 percent of cases, events such as the tsunami caused by the activity of the Krakatoa volcano in Indonesia, which generated waves of up to 50 meters, are known.
The famous Minoan civilization that inspires the legend of Atlantis was also disappeared by a tidal wave that occurred on the volcanic island of Santorini. This event managed to destroy the city of Teras towards the XVI BC
It is believed that 65 million years ago a meteorite could fall on the Yucatan peninsula where the waves would destroy everything in its path.
There is no known historical record of the penetration of a meteorite into the sea that caused tsunamis in addition to this fact in Yucatan.
References
- Lockridge, A. (2002). A brief history of tsunamis in the Caribbean Sea. Science of Tsunami Hazards. Retrieved October 7 from: ingentaconnect.com
- Bolt, B. (1977). Geological Hazards. Earthquakes, Tsunamis, Volcanoes, Avalanches, Landslides and Floods. New York: Springer-Verlag. Retrieved on October 7, 2017 from: books.google.es
- Romero, G. (1983). How to understand natural disasters. Retrieved on October 7, 2017 from: disasters.hn
- Espinosa, J. (sf). Impacts of ocean phenomena. Retrieved on October 7, 2017 from: cidbimena.desastres.hn