Researchers find source of 1964 devastating Alaska tsunami

U.S. federal scientists say they've pinpointed thecause of tsunami waves that destroyed an Alaska village followingthe 1964 Great Alaska Earthquake, the second-largest ever recorded,at magnitude 9.2.

The U.S. Geological Survey (USGS)says undersea landslides in water upto 350 metersdeep triggered a tsunami that killed 23 people in thePrince William Sound village of Chenega.

That's far deeper than the underwater slides that sent deadlytsunami waves into the towns of Valdez, Seward and Whittier.

Undersea mapping shortly after the quake reached only about 100 meters, and the cause of the Chenega tsunami previously was a mystery.

USGS researchers used multi-beam sonar and other tools to findevidence of deeper slide.

The deadly waves reached Chenega four minutes after theearthquake.