This is an image of the eruption of Mt. Pinatubo.
Click on image for full size
Image from: U.S. Geological Survey

Eruptions

Volcanic eruptions come in many different forms. Some eruptions only contain lava and hot gas. These lavas move slowly, at walking speed or slower. Other eruptions contain lava accompanied by clouds of ash, bombs, lava fragments, as well as hot gases.

In some eruptions, ash and lava, carried by hot vapors, can pour down a volcano with speeds of about 100 miles per hour. This special type of eruption destroyed the city of St. Pierre in 1902 in a matter of minutes.

In other cases, the eruption can melt snow and ice at the peak of the volcano, and a mass of mud and lava can sweep rapidly down like a river, and destroy everything in its path.

Some famous eruptions in Earth history include Mt. Pelee, Krakatoa, Crater Lake (formerly Mt. Mazama), Mt. Vesuvius, Mt. St. Helens, Mt. Pinatubo.


Last modified May 22, 2008 by Becca Hatheway.

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