Hi All. About two years ago the boss lady had me look for some data for her that covered some of the larger quakes in northern California. During the hunt I came across this article that had been printed in the Seattle Times. At the time I found it I didn’t pay that much attention to the article, but did file it away for future reference. I thought now would be a good time to purge some of the old files to make room for some new ones. I opened this one to see what was there and the first thing I saw was the second paragraph. Now that one really jumped out at me. I think you may find it interesting. The article was posted on December 3rd 1998. Take Care…Don in creepy town.

If "The Big One" hit during our lifetime, it would strike closer to home than previously thought, causing the ground to shake violently for two minutes or more.

So say University of Washington geophysicists who tapped the reliability of global satellites to confirm that an offshore fault has enough oomph to produce a magnitude 9 earthquake in the Puget Sound area.

Three years' worth of satellite data bolster past theories that when the offshore Juan de Fuca plate dives under the North America plate, the maneuver is less than graceful.

The buckling, dragging and squeezing steadily bumps the North America plate toward the northeast, as indicated by a monitoring station in Neah Bay that inches northeastward less than a half-inch a year. And the two plates jam against each other across a section about 60 miles wide - a so-called "lock zone" that builds up energy.

The pent-up energy and ground elevation that build up over centuries all slip away within seconds during an earthquake. Geologic evidence - fallen land, drowned trees, tsunami deposits - strongly suggests that a past mega-quake occurred in this area and that a future damaging event awaits.

The new data "don't change the magnitude of the earthquake we expect," said Anthony Qamar, a UW research associate geophysics professor. "It just suggests the (ground) motion would be a little stronger than if the locked zone weren't so wide."

An offshore quake would produce the strongest shaking near its source, said Qamar. But because the lock zone is wider than originally thought, its outer margin is now closer to populated Puget Sound. In addition, there's less cushioning ground between us and the potential earthquake's shallow hot spot.

The bottom line? If the area of concern, called the Cascadia Subduction Zone, ruptured along its length - as happened 300 years ago - the region would be rocked by a magnitude 8 or 9 earthquake that could rumble and shake for up to three minutes. Devastating tsunamis and large aftershocks would follow.

An earthquake that shook Seattle in 1949 for 10 seconds killed eight people and had an epicenter that was relatively deep. Because the city has grown, if a magnitude 7.5 earthquake (slightly larger than the 1949 quake) occurred now, it would kill at least 2,000 and injure nearly 9,000, according to a U.S. Geological Survey estimate.

Some newer, taller buildings have been constructed to withstand an assault by a magnitude 8 or 9 quake, Qamar said. But all-brick buildings in Pioneer Square, for example, would quickly crumble.

The military global positioning system has been used by ship captains, hikers, farmers and Antarctic explorers. But this marks the first time the UW has used the satellite array in earthquake hazard research.

The team anchored rocket-like antennas to bedrock from Cape Mendocino, Calif., to the south and Whistler, B.C., to the north.

They inferred the movement of the rock by changes in the location of the antennas.