The world’s most powerful earthquakes are more likely to occur at times of a full or new Moons. During this time, the tidal stresses on earth are highest due the gravitational pull from the moon, according to new study.
Some of the largest earthquakes such as the 2004 Magnitude 9.3 Indian Ocean earthquake, the Magnitude 8.8 Maule earthquake that devastated Chile in 2010 and the 2011 Magnitude 9.0 Tohoku-Oki earthquake that caused the Fukushima nuclear power plant meltdown, appeared to have occurred during full moon, that is – at times when tidal stress is highest. And scientists think it could be the result of a cascading process, where tiny failures in the fault lines building up into gigantic ruptures underground. Interestingly, there was no clear correlation found between tidal stress and small earthquakes.
“Every day, numerous small earthquakes occur worldwide. A very small fraction of these events grows into giant earthquakes,” said Satoshi Ide, lead author of the study. “It is a long-standing problem as to whether we can estimate the final size of an earthquake at the moment of initiation of a dynamic rupture from a small nucleus.”
“The present results suggest that the final earthquake size can be estimated probabilistically. Knowledge of the tidal stress state in seismic regions can be used to improve probabilistic earthquake forecasting, especially for extremely large earthquakes,” he added.
Source: Mail Online
Reference: Earthquake potential revealed by tidal influence on earthquake size–frequency statistics – Nature Geoscience