Japan, this is how the earthquake originated.Ingv:“Beware of fake news”

The point where the magnitude 7.5 earthquake in Japan originated is a meeting point between four tectonic plates

ROME – After the two very violent earthquakes that occurred in Japan, the National Institute of Geophysics and Volcanology analyzed the first information that emerged.From a tectonic point of view, the event occurred in an area where 4 tectonic plates interfere with each other:the Eurasian plate to the West, the Pacific plate to the East, the Philippine plate to the South and the North American plate to the North.In this kinematic framework of convergence between plates, "the focal mechanism of the compressional earthquake, with an axis of maximum shortening NW-SE, is fully coherent".

The strongest shock, that of 16.10 (Italian time 8.10), had a magnitude estimated at 7.5 by the USGS (the United States Geological Survey).Ingv instead attributed a Mwp magnitude of 7.1, while the Japan agency (JMA) estimated a magnitude of 7.6.The impact of the earthquake on the mainland was very significant.However in the early hours, especially on social media, they are found unverified information (for example, images and videos of other earthquakes are often reused) and therefore we must be very careful not to spread incorrect data, by referring to official websites or reliable newspapers – underlines INGV – we have information that describes a situation of significant damage and impact of tsunami waves.

The earthquake, INGV reconstructs, was preceded by a 5.5 magnitude shock which occurred 4 minutes before and in the following 2 hours there were about ten strong replies, the strongest of these measuring 6.2 magnitude.The JMA issued the tsunami warning immediately after the earthquake.Tide gauges on the western coast of Japan have confirmed that a tsunami was actually generated, the maximum wave heights were measured in Wajima (120 centimetres).It should be remembered that tsunami waves can be dangerous even if less than a meter high due to their speed and length.The INGV Tsunami Warning Center also followed the warning from the Seismic Monitoring and Tsunami Warning Room.