At http://phys.org/print344769202.html … evidence of a massive tsunami wave that struck the eastern side of the Yucatan Peninsular has been found. It is claimed it occurred 1500 years ago, at some point after AD450. It could have been caused by an underwater land slip, a Caribbean volcano, an earthquake, or a meteorite strike. No chance of knowing. Even the date is wide open as it is presently dated somewhere between 450 and 900AD. It requires a more secure dating analysis, using C14 on sediments from above and below the tsunami level.