Scientists currently working off west Africa in the Cape Verde Islands have found evidence of a mega tsunami caused by the sudden collapse of a volcano around 73,000 years ago. This collapse created an 800-foot wave that swallowed an island more than 30-miles away.”Our point is that flank collapses can happen extremely fast and catastrophically, and therefore are capable of triggering giant tsunamis. 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,” said lead author Ricardo Ramalho, who did the research as a postdoctoral associate at Columbia University’s Lamont-Doherty Earth Observatory. Continue reading for another video on mega tsunamis and more information.
“On July 9, 1958, an earthquake shook 90 million tons of rock into Alaska’s isolated Lituya Bay; this created an astounding 1,724-foot-high wave, the largest ever recorded. Two fishermen who happened to be in their boat that day were carried clear over a nearby forest; miraculously, they survived. These events, however, occurred in confined spaces. In the open ocean, waves created by landslides are generally thought to lose energy quickly, and thus to pose mainly a regional hazard. However, this is based largely on modeling, not real-world experience, so no one really knows how fast a killer wave might decay into a harmless ripple,” reports Mail Online.