OPED25 Mega-Tsunami

In July 1958 in Lituya Bay, Alaska, an earthquake struck measuring around 8 on the Richter scale. This triggered a collapse in which an estimated 40 million cubic yards of dirt slid into the bay, which in turn generated a massive wave that devastated the area. From the height to which all trees were denuded off the slopes it is estimated that the wave was a staggering 1,720 feet  high at its highest point.

Some references to Lituya Bay:   Mega-Tsunami. Charles L. Mader    -    Biggest Wave - Lituya Bay Tsunami    -    Lituya Bay Close-Up

Mega-tsunamis are gigantic waves up to and exceeding 100 feet that can be triggered by similar events. Evidence of past mega-tsunamis exists in various places around the globe. For example, in the Bahamas there are 123,000 year old deposits including boulders weighing up to 2000 tons that are up to 20 meters above sea level and at least half a kilometer inland. These are theorized to have been deposited by a mega-tsunami caused by the El Golfo I collapse in the Canary Islands.
Now, scientists have identified a fault in the Canary Islands that sometime in the future could perhaps cause a mega-tsunami. The Cumbre Vieja volcano is found on La Palma in the Canary Islands. La Palma is one of the steepest island in the world, as well as being the most active volcanic island in the Canaries. In 1949 an eruption caused a fault to occur on the flank of the volcano, and the entire west flank of the volcano moved 4 meters seaward before stopping. Since then there has been no further movement, but it is anticipated that eventually during future eruptions there will be a collapse. A chunk of the island the size of the Isle of Man will fall into the sea creating a mega-tsunami. Scientists have attempted to computer-model the results... one model suggests that following this event the main wave would travel westwards, reaching the east coast of the Americas six hours later, at which time the wave will still be an estimated 100-150 feet high, causing unimaginable damage.

A few relevant links (a Google search shows hundreds of news reports):

See a cross-section of La Palma showing the Cumbre Vieja volcano and fault
Mega-tsunami to devastate US coastline
Scientists warn of massive wave

Scientists are monitoring and studying Cumbre Vieja and caution that this should not happen for hundreds or perhaps even thousands of years, but that it will happen eventually. This writer has no idea of the technical issues involved (i.e. if this is a danger or not) but given the massive media exposure these reports were given and the lurid headlines (e.g. see above links) it would be a good idea to keep an eye on the area from a security standpoint in case terrorists try to trigger this event with a nuclear device.

© SNi 06/24/02