SEATTLE -- The Washington coast has felt the tremors of a megaquake in the past.

But results of a new study shows Seattle may feel them as well.

Scientists at Central Washington University believe a magnitude-9.0 quake off the coast could do much more damage throughout Western Washington than previously predicted.

Their GPS research shows the shaking and damage would reach within 50 miles of Seattle.

The CWU study mirrors research being conducted at the University of Washington.

"And people have been suspecting that it is getting closer for about 10 years now," said John Vidale of the Pacific Northwest Seismic Network. " You know, 20 or 30 years ago, we didn't even know that there were great earthquakes on the coast."

Vidale says those in and around Seattle would feel the shaking from the Cascadia subduction zone in the Pacific for not just seconds, but rather for several minutes.

"Closer to Seattle, so the shaking's likely to be a lot stronger than we expected, maybe 10, 20 percent stronger," he said.

And a megaquake of 9.0 reverberating closer to Seattle brings renewed concern for any building, especially skyscrapers built before 1994.

Scientists at the California Institute of Technology estimate at least half our downtown buildings were built before then.
As a result, may believe the focus should be on retrofitting all those buildings.

"These earthquakes only happen every 500 years so it's nothing that's certain to destroy the city in the near future," said Vidale.

But there is a chance.

Seattle was last hit with a megaquake in 1700. Are we due for another?. There's just now way of knowing.