Scientists working off west Africa in the Cape Verde Islands have found evidence of a megatsunami that dwarfs anything humans have ever seen. They say the sudden collapse of a volcano around 73,000 years ago created an 800-foot wave that engulfed an island more than 30 miles away. They warn the collapse of volcanoes could be far more catastrophic that previously thought. The study appears today in the journal Science Advances, and revives the debate over whether sudden giant collapses present a realistic hazard today around volcanic islands or distant continental coasts.

‘Our point is that flank collapses can happen extremely fast and catastrophically, and therefore are capable of triggering giant tsunamis,’ said lead author Ricardo Ramalho, who did the research as a postdoctoral associate at Columbia University’s Lamont-Doherty Earth Observatory. ‘They probably don’t happen very often.  ‘But we need to take this into account when we think about the hazard potential of these kinds of volcanic features.’ The apparent collapse occurred some 73,000 years ago at the Fogo volcano, one of the world’s largest and most active island volcanoes.  Nowadays, it towers 2,829 meters (9,300 feet) above sea level, and erupts about every 20 years, most recently last fall. CONTINUE