Earthquakes linked with tide, say Japanese researchers

Japanese researchers believe they may be closer to predicting an earthquake, but it hasn't come without criticism.

After 20 years research of quakes with a magnitude of 5.5 or higher, University of Tokyo academics say they've found a link between high tide, and large earthquakes.

They say it could indicate a greater likelihood of events following a new, or full moon.

But University of Melbourne Associate Professor Mark Quigley warns it's a hypothesis and not an absolute finding.

He says there are abnormalities in their results, and the 5.7 magnitude earthquake that occurred near Christchurch in February is a good example of this; it didn't occur near any major tidal events.

While he won't rule out tides completely, he says history shows other seismic events play more of a role in triggering future earthquakes.

Because of this he wants to urge future researchers to focus their resources on minimalising the impact of earthquakes, instead of predicting them.

He says scientists know that giant subduction zones can generate a magnitude nine earthquake, so predicting them won't prevent fatalities.

"Rather than trying to put a date on the calendar we need to keep in mind there have been many, many full moons, many, many new moons without any earthquakes at all... we need to be focusing on things like better sea walls, better avoidance zones from hazards, and better engineering needs to be the priority."