The Pacific Ring of Fire has shocked the region with 46 separate earthquakes in 24 hours this month, as preparations continue for the "highly imminent" megaquake capable of wiping out cities.
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Fears of another devastating earthquake and tsunami are growing in Japan after multiple sightings of the rare and ominous oarfish. According to legend, large snake-like creatures come to the surface and beach themselves on land ahead of underwater earthquakes.
Just days ago a magnitude 6.2 quake struck off northern Japan, about 184km of the city of Nemuro in the Hokkaido region. This quake struck at a depth of just 10km.
It was part of a mass of recent activity that included a magnitude 7.1 earthquake off southern Peru, 67km north-northwest of Juliaca. The quake sparked mass evacuations and the effects were strong enough to be felt in Brazil, Bolivia and Chile.
The 'Ring' is a horseshoe-shaped loop running from New Zealand to Chile. About 90 percent of the world's earthquakes happen in the Ring, where three-quarters of the world's active volcanoes are located.
Scientists say it's statistically likely to have regular activity somewhere around the ring at any given time.
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"It's not referred to as the "ring of fire" because it sits there doing nothing," volcanologist Dr Janine Krippner said on Twitter.
"It is a constantly-moving, very active (and huge) area full of faults and active volcanoes."
However Japan is already stepping up preparations for another magnitude-9 earthquake after warnings that another disaster is "highly imminent".
Earthquake experts have noticed changes in the Kuril Trench area off the Japanese coast - the same changes in seismic activity that were seen before the March 2011 earthquake which triggered a giant tsunami that killed almost 19,000 people and heavily damaged the Fukushima nuclear plant.
According to Japan's Earthquake Research Committee, a 2017 analysis of historical data predicts an earthquake will probably occur off the Pacific coast of Hokkaido and trigger a tsunami within 30 years.
"There is an extremely high probability. The chances of an earthquake like the East Japan Earthquake occurring on the Kuril Trench are high," committee chairman Naoshi Hirata warned.
The last such megaquake caused a tsunami over 20 metres high which reached about four kilometres inland, researchers at Hokkaido University say.