An earthquake of magnitude 4.7 hit the Greece at 4:20 (3:20 in Italy). As reported by the Ingv, the epicenter was located a 11 km east of Uranopolia town with less than 1000 inhabitants in North Eastern Greece, at a depth of 9 km. As often happens, the first temporary estimates are slightly different: the USGS (United States Geological Survey) reported a magnitude of 4.9 and a depth of 12.2 km. In the next few hours the most accurate investigations will allow the two results to converge. Fortunately, however, at the moment the authorities do not report particular damage to things or people.
But from a geological point of view, what were the causes of this earthquake? To have a clearer vision we can consult the following image taken from the USGS website.
As we can see the whole Greek area is dotted with Fulls: Each represents a historical earthquake that occurred in the area. The more the color of the dots is dark and the greater the depth of the hypocentro, while their size is directly proportional to the magnitude. Even in the area of today’s earthquake, in the north-eastern portion of the country, there are numerous historical earthquakes and all, at the macroscala, are attributable to the subduction from the African plate (south) below that Eurasian (north). Specifically, the subduction rate here is equal to approximately 10 millimeters per yearwhile it is slightly lower in the western Mediterranean.
