No Earth-shaking evidence of quakes linked to the moon
Random patterns can explain how the moon and sun may appear to affect the timing of earthquakes, say scientists.
Devastating earthquakes cannot be blamed on the moon or time of year, according to myth-busting scientists.
There is an enduring belief that the influence of the moon or sun may help trigger large earthquakes.
But this was not supported by the new study, which matched dates and lunar phases to 204 quakes of magnitude eight or larger.
The position of the Earth relative to the moon or sun had no bearing on the timing of earthquakes.
Lead researcher Dr Susan Hough, from the US Geological Survey, said patterns reported to link big earthquakes with specific stages of the lunar cycle were “no different from the kinds of patterns you would get if the data are completely random”.
However she admitted that the moon and sun’s gravity do cause ripple-like tidal stresses through the body of the Earth.
This may contribute “in a small way” to early earthquake processes, said Dr Hough. The effect was too insignificant to be useful for predicting tremors.
While the analysis turned up some clusters of earthquakes on certain days, a closer look found no evidence that they had appeared non-randomly.
“When you flip a coin, you sometimes end up with five heads in a row,” Dr Hough pointed out.
The findings appear in the journal Seismological Research Letters.
Dr Hough, who said belief in a link between the sun and moon’s position in the sky and earthquakes had a “long history”, added: “Sooner or later there is going to be another big earthquake on a full moon, and the lore will pop back up.
“The hope is that this will give people a solid study to point to, to show that over time, there isn’t a track record of big earthquakes happening on a full moon.”