Watch the volcanic eruption of Mount Saint Helens and subsequent flooding caused by melted glaciers
Watch the volcanic eruption of Mount Saint Helens and subsequent flooding caused by melted glaciers
On May 18, 1980, as geologists watched in awe, Mount Saint Helens erupted with tremendous force.
Encyclopædia Britannica, Inc.
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Encyclopædia Britannica, Inc.On May 18, 1980, as geologists watched in awe, Mount Saint Helens erupted with tremendous force.
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Encyclopædia Britannica, Inc.Volcanic activity at Kilauea in Hawaii.
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Encyclopædia Britannica, Inc.Spectacular fountainlike eruptions at Kilauea volcano, Hawaii, are followed by streams of fluid lava flowing down the mountainside.
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Encyclopædia Britannica, Inc.Beginning in November 1963, an eruption of ash and lava from the seafloor off the coast of Iceland forms a new volcanic island, Surtsey.
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Encyclopædia Britannica, Inc.The eruption of Paricutín lasted for nine years and produced one of the world's youngest volcanoes. Ash and lava began spewing from an open field in 1943 in Michoacán state, Mexico, and buried nearby settlements and farmland and displaced local people. The result was a new cinder cone volcano. This video, produced in the 1970s, includes footage taken during the eruption.
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Encyclopædia Britannica, Inc.Lava flowing toward the sea from Kilauea volcano, Hawaii, takes two recognizable forms: fast-flowing ropy lava called pahoehoe and thick blocky lava called aa.
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Encyclopædia Britannica, Inc.Do you risk explosion?
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Encyclopædia Britannica, Inc.Volcanologist Janine Krippner dives into the details.
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Encyclopædia Britannica, Inc.Some of the world's tallest mountains are actually growing.
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Transcript
[Music in]
NARRATOR: It is the Spring of 1980.
Crowds of scientists have gathered to take the pulse of an awakening volcano in Washington State. Mount St. Helens. They measure the deep underground rumblings, and the earthquakes that are wracking her frame. They set up instruments to monitor the eruption they believe is coming.
SCIENTIST: 845
NARRATOR: They observe the clouds of steam, gas, and ash pouring from her summit . . . and on Sunday, May 18th, at 8:32 A.M. . . . some of them die.
[Music out]
For at that moment, without warning, the North flank of the volcano simply blew out, in a shattering explosion heard up to three hundred miles away.
EYEWITNESS: The whole sky was just billowing and just puffing out with smoke, and it had me nervous. I ain't kiddin' ya.
NARRATOR: Massive cloud of superheated gas and debris roared down the mountainside at two hundred miles an hour . . . a cloud of awesome destructive power.
EYEWITNESS: It is ominous, and it's--it's right there, and we--we came to a screeching halt. We turned the jeep around, and we drove away at like 85 miles an hour with this gaseous fall just--almost engulfing us.
INTERVIEWER: Did you smell it?
EYEWITNESS: Couldn't smell it; couldn't hear it; could see it.
NARRATOR: In seconds, the scalding gases melted centuries-old glaciers. Boiling hot water scoured the hillsides, uprooting entire forests. An hour after the blast, a raging wall of water, logs, and liquefied soil . . . at times twenty-five feet high . . . roared down the South Toutle River, sweeping away everything in its path. The wall slammed into the valleys below, catching residents almost totally by surprise. In a matter of seconds, thousands of people saw their lives torn apart by the torrent, as hundreds of homes were swept off their foundations, and smashed to pieces.
[Music in]
As for the mountain . . . its majestic crest was gone. And a gaping, horseshoe-shaped crater stood in its place.
Before the eruption, Mount St. Helens was ninety-seven hundred feet high. After . . . eighty-four hundred. Thirteen hundred feet of the mountain had been vaporized, and turned into millions of tons of choking, powdery ash. Over two hundred square miles of forest, uncounted wildlife, and sixty-five human beings . . . were destroyed.
[Music out]
NARRATOR: It is the Spring of 1980.
Crowds of scientists have gathered to take the pulse of an awakening volcano in Washington State. Mount St. Helens. They measure the deep underground rumblings, and the earthquakes that are wracking her frame. They set up instruments to monitor the eruption they believe is coming.
SCIENTIST: 845
NARRATOR: They observe the clouds of steam, gas, and ash pouring from her summit . . . and on Sunday, May 18th, at 8:32 A.M. . . . some of them die.
[Music out]
For at that moment, without warning, the North flank of the volcano simply blew out, in a shattering explosion heard up to three hundred miles away.
EYEWITNESS: The whole sky was just billowing and just puffing out with smoke, and it had me nervous. I ain't kiddin' ya.
NARRATOR: Massive cloud of superheated gas and debris roared down the mountainside at two hundred miles an hour . . . a cloud of awesome destructive power.
EYEWITNESS: It is ominous, and it's--it's right there, and we--we came to a screeching halt. We turned the jeep around, and we drove away at like 85 miles an hour with this gaseous fall just--almost engulfing us.
INTERVIEWER: Did you smell it?
EYEWITNESS: Couldn't smell it; couldn't hear it; could see it.
NARRATOR: In seconds, the scalding gases melted centuries-old glaciers. Boiling hot water scoured the hillsides, uprooting entire forests. An hour after the blast, a raging wall of water, logs, and liquefied soil . . . at times twenty-five feet high . . . roared down the South Toutle River, sweeping away everything in its path. The wall slammed into the valleys below, catching residents almost totally by surprise. In a matter of seconds, thousands of people saw their lives torn apart by the torrent, as hundreds of homes were swept off their foundations, and smashed to pieces.
[Music in]
As for the mountain . . . its majestic crest was gone. And a gaping, horseshoe-shaped crater stood in its place.
Before the eruption, Mount St. Helens was ninety-seven hundred feet high. After . . . eighty-four hundred. Thirteen hundred feet of the mountain had been vaporized, and turned into millions of tons of choking, powdery ash. Over two hundred square miles of forest, uncounted wildlife, and sixty-five human beings . . . were destroyed.
[Music out]
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