Earthquake swarm keeps Spokane rocking

SPOKANE, Wash. -- The temblors come day and night. Schools hold duck-and-cover drills. Workers in downtown high-rises study evacuation plans.

For the past six months, Spokane has been in the throes of what experts call an "earthquake swarm." More than 75 have been recorded since May 24, and dozens more could not be measured because of a lack of seismographs.

There have been no injuries or major damage -- other than bricks falling from chimneys and items tumbling off shelves -- but nerves are fraying.

"We've felt every single one of them," said Cindy Burrows, who works on the 19th floor of the Bank of America Financial Center, downtown's tallest building. "The building doesn't sway. It jumps."

One quake caused such a jolt she had to hang onto her desk, Burrows said.

The high number of earthquakes was unexpected in a metropolitan area thought to be on solid ground, experts say. While none has registered more than a magnitude 4, scientists have no real idea if a big one is looming.

"If they get much bigger, we will start seeing more serious damage," said Tom Yelin of the U.S. Geological Survey, which has sent additional equipment and people to Spokane to study the phenomenon.

Spokane, a city of 190,000 in eastern Washington, has had no major earthquakes in its 120-year recorded history and wasn't regarded as being in an earthquake zone.