Waiting for the Second Geological Shoe to Drop

By Michael D. Lemonick/New York and Dick Thompson/Washington

Causing more than 200 injuries and well more than $2 billion in damage, last week's 6.8-magnitude Pacific Northwest earthquake was bad enough--but it wasn't the Big One experts say is still to come. While geologists predict a mega-quake still lies in Seattle's future, they are also looking at a different, equally dangerous big one that is literally looming on the city's horizon: MOUNT RAINIER, the snowcapped volcano that lies 50 miles to the southeast. Though slumbering, Rainier is still active, and last week's quake might have loosened deep rocks that hold molten magma and hot gases in check. This could send up the volatile mix and cause an eruption. Several towns are built on top of Rainier's ancient flows--and lie in the path of new ones that would follow. Luckily, though, the slowly rising magma would likely trigger steam explosions, giving scientists ample warning. A quake can also trigger huge landslides, sending enormous slabs of boulders and clay downhill as fast as a speeding train. Fortunately, the region has had a relatively dry winter; otherwise, say experts, Rainier might already have shed part of its normally waterlogged skin, with deadly results.

--By Michael D. Lemonick/New York and Dick Thompson/Washington