SEISMICALLY ACTIVE – JAPAN’S LONG HISTORY OF EARTHQUAKES – Earthquakes are common in Japan, one of the world’s most seismically active areas.
Earth will be at its closest point – some 221,567 miles away – to the moon in 19 years on March 19
The country accounts for about 20 per cent of the world’s earthquakes of magnitude 6 or greater.
Several continental and oceanic plates meet in the Japan area, which is why there are so many volcanoes and hot springs across the nation.
Located in a volcanic zone so active it is nicknamed the Pacific Ring of Fire, catastrophic earthquakes occur several times each century.
Japan has suffered an estimated 200 recorded tsunamis in its history due to earthquakes that take place below or close to the Pacific Ocean.
In October 2004, an earthquake with a magnitude of 6.8 struck the Niigata region in northern Japan, killing 65 people and injuring more than 3,000.
That was the deadliest quake since a magnitude 7.3 tremor hit the city of Kobe in 1995, killing more than 6,400.
WHAT CAUSED THE EARTHQUAKE?
Dr Roger Musson, of the British Geological Survey (BGS), explained that the devastating earthquake occurred because the Pacific Plate is plunging underneath Japan.
He said: ‘The cause of this earthquake is that the Pacific Plate, which is one of the largest of the tectonic plates that makes up the crust of the Earth, is plunging deep underneath Japan.
‘It’s being pushed down and it can’t slide down smoothly so it sticks.
‘It sticks for tens of years and then eventually it breaks and moves very suddenly down and as it does so it buckles and gives the seabed a sudden kick over areas of hundreds of square kilometres and that displaces an enormous volume of water.
‘That water just races away in the form of this enormous wave in all directions.’ ( Dailymail )