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All are hoping, of course, that the volcano will cooperate by keeping quiet. But will it? Geologists are reluctant to forecast the future. Reconstructing last year's disaster with readings from seismographs and tiltmeters — which measure the swelling of the earth's surface — scientists have determined that the eruption was triggered by a magnitude5 earthquake that shook the mountain on May 18, the day of the volcano. The tremor dislodged a flank of the mountain already swollen from rising semimolten rock. A huge hunk of the mountain rumbled downhill like a great sliding door, uncovering rock saturated with compressed gases. Exposed to the air, the gases exploded. Geologists are encouraged by the fact that the lava dome that has been forming in Mount St. Helens' crater now appears to be stable, capable of serving as a cork for the mountain's bottled-up gases and the lava that is still rising. But no one will say that Mount St. Helens is ready to settle down. The mountain, says one of her geological suitors, is too much like a woman. "Just when you think you've got to know her," he says, "she changes her mind."
— By Peter Stoler.
Reported by Joseph Kane/Mount St. Helens