What are the chances that Mallorca will ever suffer from the effects of a Tsunami, you may have asked yourself since you saw the dramatic images of last week’s tragic events in Japan.
The Japanese word Tsunami can literally be translated as ‘harbor wave’. In the strictest sense, Tsunami waves can happen not only in far away places like Japan or Thailand but, here in the Mediterranean Sea basin as well. In fact, I believe that there have been about 20 Tsunamis reported in the Mar Mediterráneo over the last 2000 years. Tsunamis can be generated by earthquakes, volcanic eruptions, underwater explosions, landslides and other disturbances above or below water. Chances for the very big Tsunami waves are obviously greater in the big open expanse of the world’s large oceans, where the waves can gather enormous speed and travel over large distances. Bigger waves are also caused by bigger earthquakes than those occurring around here. Last week’s earthquake in the North Pacific Ocean causing the Tsunami that caused so much damage on Japan’s North East coast was of a magnitude of 9.0 on the Richter scale whereas the biggest earthquake ever suffered in Mallorca was one happening some 500 km away in 2003, just south of Algiers (Algeria) with a magnitude of only 6.6. Even though, substantial damage to boats and moorings was suffered in the ports of Mallorca’s South coast at that time. There are also reports of a Tsunami affecting the coast of Santanyí way back in 1750.
Basically, natural disasters can happen anywhere in the world but, chances for severe earthquakes or large Tsunamis are considerably less likely here in Mallorca. There is no tectonic fault line here in Mallorca. In geological terms, Mallorca forms part of the Eurasian Plate which joins on to the African Plate somewhere in the south of North Africa. In Mallorca, you need not worry too much; Morocco and Algeria are relatively far away.
There is a different type of Tsunami called a Meteotsunami that seems to occur with some regularity in the Port of Ciutadella in Menorca. The phenomenon is called a Rissaga in Catalan. Such a Meteotsunami or meteorological Tsunami is a Tsunami-like wave circumstance of meteorological origin. A Rissaga might be called an inverse Tsunami as the water suddenly recedes almost totally from a harbour basin before it comes back with a vengeance creating a large wave that occasionally causes considerable damage. Rissagas have only been reported in Mallorca on rather small scales. I’ll report some more on the subject of Rissagas next time there is one, either here or in Menorca.
The photo was taken near Porto Cristo, Mallorca, Baleares, Spain. The date: March 13th, 2011. The time was 16:52:46.