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Scientists seek ways to withstand tsunamis
12/27/2005
CORVALLIS, Oregon, Dec 26 (AP): Tsunamis much like the deadly wall of water that swept across the Indian Ocean a year ago have struck the US West Coast at least 16 times, most recently in 1700.
It is only a matter of time before another one strikes. And when it does, some coastal cities may have as little as 15 minutes warning before the tsunami reaches them, said Chris Goldfinger, an Oregon State University professor of marine geology.
Tsunamis are very long waves that are led by a depression in the water. When the leading edge of the tsunami gets close to shore, the depression arrives first, often draining the beaches of water before the wave arrives.
Goldfinger and other researchers are working at the Hinsdale Wave Research Laboratory at Oregon State to study tsunami behavior and find ways to reduce the risk to coastal cities, or at least increase the chances of survival.
The Hinsdale facility includes a $4.8 million (euro4 million) tsunami wave basin, an enormous tank with a wave generator that can simulate tsunami waves as they approach a coastline and assess the level of damage they can cause.
The lab - the largest of its kind in the world - has run a sophisticated simulation on the impact a tsunami could have on the densely populated Puget Sound area of Washington state, which includes the Seattle area. Researchers plan to release the results at an international meeting in February, Cox said.
The coast is at risk because of a long, sloping fault called the Cascadia Subduction Zone stretching 600 miles (965 kilometers) undersea from mid-Vancouver Island in Canada to Northern California.
The zone is the junction of two huge sections of the Earth's crust - called the Juan de Fuca and North America plates - where new ocean floor is being created and pushed beneath the continent, building up pressure that sets the stage for enormous earthquakes that reach magnitude 9 or higher.
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