THE municipalities of Palma, Inca, Sa Pobla and Campos will be those most affected by the aftershock of an earthquake measuring above 7 degrees on the Richter scale, an event likely to occur in the Balearics every 400 years.
Seismic expert, Jordi Jimenez said yesterday that Minorca and Majorca had the highest likelihood of an earthquake of over 6 degrees on the Richter scale (a quake of 8 degrees is generally considered to be highly destructive) happening every 400 to 500 years.
Jimenez, who has taught at the Balearic University and is one of a team mapping out a Balearic plan to cope with seismic emergencies (Geobal), warned that municipalities lying on soft ground such as the aforementioned four, will be most affected.
The reason for this, he explained, is that it is soft ground which is most prone to giving off the highest amount of vibrations at the fastest speed, thus shaking buildings the most. Seismic waves apparently travel more slowly on rocky or hard terrain.
The work being carried out within the framework of the Geobal plan is therefore of the utmost significance. It analyses the vulnerability of individual municipalities and looks particularly at how tourist accommodation would be affected in the event of a quake, given as they are frequently built on soft, sandy, ground.
Jimenez, however, said that the Balearics would have to wait a thousand years or so before experiencing an earthquake that razed buildings to the ground.
The issue came a little closer to home when he pointed out that the last particularly strong earthquake hit Majorca in 1851 when the Marratxi area of Palma was hit by a quake measuring 8 degrees on the Richter scale. It badly affected Pla de Na Tesa and Portol and one of the many aftershocks brought down the church of Sant Marcal.
Apart from the quake of 1851, the Geobal project has retrieved information about 53 others occasions of seismic activity which have occurred in the Balearics from 1654 to 2003 when there was a small tsunami produced by an earthquake which happened along the fault line of Algeria.