Earthquakes in the 'Ring of Fire' terrorising the Pacific

Earthquakes in the 'Ring of Fire' terrorising the Pacific

A series of big earthquakes in less than 24 hours could have been caused by seismic waves travelling along fault lines and triggering ruptures.

A 6.1 magnitude earthquake hit New Zealand on Wednesday followed by others off the coasts of Japan (6.1), Vanuatu (6.4), and Indonesia (5.7) early Thursday morning.

All were along the 'Ring of Fire' that stretches around the Pacific from New Zealand to Chile through Indonesia, Japan, and California, across which 90 per cent of quakes happen.

There was also a big earthquake in Mexico City that killed more than 230, but despite the country falling in the 'Ring', experts ruled out a connection to the other quakes.

University of Melbourne's Gary Gibson said that the 7.1 magnitude quake in Mexico was isolated thousands of miles away from the other seismic events and therefore unlikely to have triggered any cascade effect within the tectonic plates.

Seismologists admitted the cluster of quakes, along with others near Tonga (5.0), Taiwan (5.3), and Papua New Guinea (5.2), on the same day was 'unusual'.

'It is unusual, there's no doubt about that, it's been really busy,' Dr. Gibson told Daily Mail Australia.

'I must say these unusual clusters happen fairly often and it seems they are not totally random, we just don't know why.'

Phil Cummins at Geoscience Australia and the Australian National University suggested seismic waves cascading along fault lines could be responsible.

He said waves could also jump between nearby fault lines and continue moving, triggering imminent earthquakes at rupture points.

'The waves that are excited by the earthquakes might rattle or disturb some distant faults that are close to rupture already,' he said.

Professor Cummins said seismic waves couldn't create earthquakes by themselves, but could bring forward ones already about to happen.

'These are earthquakes that would almost certainly have happened very soon,' he said.

Like Mr Gibson, he said earthquakes seemed to cluster in time but there was well-established explanation why, only theoretical possibilities.

Professor Cummins also couldn't rule out the same mechanism could provoke another significant earthquake in coming hours or days.

However, both scientists ruled out any link to Wednesday's twin earthquakes in Mexico, which killed more than 230 people as they were too far away.

Mr Gibson said the first Mexican earthquake could in theory have triggered the others by creating a stress field - but they would need to be at most 200km apart.

'It is possible for earthquakes to affect a stress field and trigger more quakes, but those earthquakes would have had to be fairly imminent in the first place,' he said.

Dr. Christopher Pluhar, a professor of Geology at Fresno State, said this week that the probability of a strong quake in California in the next 30 years is around 60 percent.