TO Santorini, in the Greek archipelago of the Cicladi, The earthquakes continue uninterrupted: only in the last 24 hours there have been more than 139, magnitude up to 5.0 (data of the University of Athens). In reality this value changes according to the source consulted: according to the INGV the maximum magnitude would even be of 5.4 while according to the USGS (United States Geological Survey) of 5.1. The earthquake did not cause damage or injured, because it had epicenter at sea off the island of Amorgos about 40 km from Santorini. In all, over 12,000 shocks have been recorded in the last two weeks in the island area.
These are therefore still temporary values and that could converge in the next few hours. Beyond the exact magnitude, the fact remains that the area has been strongly under stress for several weeks now, considering that more than more than more than January 12 thousand shocksmany of which with magnitude greater than 4.0. Tourists were evacuated, part of the residents abandoned their homes and landslides were recorded in various areas of the island.
Currently on the island of Santorini the state of emergency has been declared which will last at least until March 3 and attention remains very high on the island of Amorgos, since the seismic swarm does not seem intent on stopping.
But what are the causes Of these seismes?
Unlike what is reported by some newspapers, we have no evidence at the moment to say that earthquakes are somehow tied to volcanic activity. In all likelihood, in fact, these are SISMI of tectonic origin, linked to subduction of the African plaque below the Eurasian one. This phenomenon is able to generate large quantities of energy that accumulate along the active fault systems and which, periodically, are released.
This is also confirmed by the image below. Here are the main historical SISMI in the area, and how we can see Greece is a particularly affected area: the size of the circles is proportional to their magnitude, while the color at the depth.
To deepen the topic, here is an ad hoc video on the geological history of Santorini:
