"Scientists have underestimated the potential for a giant quake and tsunami that could swamp much the U.S. northwest and Canadian west coasts, British and U.S. researchers said on Monday.

Geological evidence suggests there have been earthquakes in the past that were even stronger than a magnitude 9.2 quake -- the second-biggest ever recorded -- which caused a 42-foot-high (12-meter-high) tsunami in the Gulf of Alaska in 1964, they said.

'Our data indicate that two major earthquakes have struck Alaska in the last 1,500 years and our findings show that a bigger earthquake and a more destructive tsunami than the 1964 event are possible in the future,' Ian Shennan, a professor of geography at Britain's Durham University, who led the study, said in a statement.

'The region has been hit by large, single-event earthquakes and tsunamis before, and our evidence indicates that multiple and more extensive ruptures can happen.'"

Reuters had the story July 22, 2009. [2]