Hugh Pickens writes "Scientists say that sedimentary deposits from more than 20 cores in New York and New Jersey indicate a huge wave crashed into the New York City region 2,300 years ago, dumping sediment and shells across Long Island and New Jersey and casting wood debris far up the Hudson River. Steven Goodbred, an Earth scientist at Vanderbilt University, says that size and distribution of material would require a high velocity wave and strong currents to move it, and it is unlikely that short bursts produced in a storm would suffice. 'If we're wrong, it was one heck of a storm,' says Goodbred. An Atlantic tsunami is rare but not inconceivable, says Neal Driscoll, a geologist from Scripps Institution of Oceanography, who is not associated with the research. The 1929 Grand Banks tsunami in Newfoundland killed more than two dozen people and snapped many transatlantic cables, and was set in motion by a submarine landslide set off by an earthquake."