Extreme storm waves at sea have shifted a boulder weighing 620 tonnes, explaining why huge rocks are sometimes mysteriously found on high cliffs
MONSTROUS oceanic waves are able to transport boulders weighing hundreds of tonnes. The finding helps explain how huge rocks end up atop high cliffs. It also implies that storm waves, and other rogue waves, can be more powerful and hazardous than previously thought.
Until recently, the heaviest rock known to have been transported by waves was about 200 tonnes. Now Rónadh Cox of Williams College in Massachusetts and her colleagues have found a new record holder: a 620-tonne boulder, equivalent to roughly three Statues of Liberty.
Cox found the boulder on the west coast of Ireland. The region was struck by a huge cluster of storms during the winter of 2013-2014. When she and her team examined photographs taken before and after the storms, they found the massive boulder had been moved about 2.5