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A Sleeping Giant Awakes

Spanish Translation

By Jeremy Caplan

With a rumble and a roar, lava rocketed up to the top of Mount Saint Helens, in Washington, last week. The volcano has been bursting with activity since September 23, when thousands of little earthquakes hit. The 8,634-foot mountain has been heating up and spewing steam and ash ever since.

Scientists are measuring the volcano's every shudder. Last week, waves of hot melted rock, or magma, began pushing upward toward the mountaintop. Lava, which is what magma is called when it reaches the earth's surface, has been collecting steadily on the crater floor inside the volcano. The lava's temperature reaches nearly 1,700°F. Enough new rock is forming from the lava to fill an Olympic-size swimming pool every 15 minutes! Researchers say Mount Saint Helens could blow its top at any time.

The last time the volcano erupted violently was on May 18, 1980. Tens of thousands of acres of forests were destroyed and 57 people were killed. Scientists predict a less violent eruption this time. But researchers are not taking any chances. No one is allowed within about 10 miles of the volcano. "Volcanic activity is an inevitable part of the world we live in," says Jeff Wynn, the chief volcanologist for the U.S. Geological Survey. "But we're doing everything we can to make sure we're all safe this time."

Detecting Danger
Volcanoes can pass years at rest, then explode with sudden violence. Because these giants are unpredictable, studying them is a dangerous profession. Many scientists have lost their lives investigating volcanoes. But now, advanced technology can detect changes in volcanic behavior without endangering human lives.

New tools allows volcanologists to keep track of nearly any change in or around a volcano. Tiny microphones set up around Mount Saint Helens record even the smallest surface explosions, so scientists can tell whether it is acting up. Helicopters fly over the volcano's crater equipped with instruments that collect gases. Volcanologists study the gases for hints about what might be brewing inside the mountain. Tiny global positioning system devices measure the volcano's movements. That helps scientists figure out if magma is putting pressure on the mountaintop and pushing the surface aside (see diagram above).

In the future, scientists expect to rely on even more advanced technologies. Tiny pilotless planes will gather information. Nicknamed birds by volcanologists, the robotic aircraft will collect gas samples and take pictures and videos.

Watching and Waiting
For now, all scientists can do is keep an eye on Mount Saint Helens and be patient. For thousands of years, the volcano has alternated between bursts of violent activity and slumber. "It's like there's a giant on-and-off switch" says Wynn.

Geologists understand many of the factors that cause volcanic eruptions. "We've learned an enormous amount since the last eruption," says Wynn. "But there's much more we'd still love to know."

The Ring of Fire
Many of the world's volcanoes are lined up along the Ring of Fire, a belt that encircles the Pacific Ocean. This region experiences frequent earthquakes and volcanic activity. Mount Saint Helens is located in the ring. So are about 75% of the world's volcanoes!

The ring outlines a tectonic (tek-tah-nik) plate, one of seven movable pieces of the earth's crust. Scientists have learned that volcanoes are caused, in part, by the movements of the plates. The plates move and change position repeatedly over time, sometimes sliding into each other to cause volcanic eruptions and earthquakes.

Next: Discoveries Link Birds to Dinosaurs