Slide Show

A volcano is an opening in Earth’s crust. When a volcano erupts, hot gases and melted rock from deep within Earth find their way up to the surface. This material may flow slowly out of a fissure, or crack, in the ground, or it may explode suddenly into the air. Volcanic eruptions are destructive but they also create new landforms. There are more than 1,500 potentially active volcanoes in the world today.

During a volcanic eruption, hot melted rock called magma escapes from a vent, or opening, in Earth’s surface, or crust. Magma released from a volcano is known as lava. Fresh lava ranges from 1,300 to 2,200 °F (700 to 1,200 ° C) in temperature. It glows red as it flows out of the volcano’s opening. As it cools, it hardens into rock.

Strong volcanic eruptions throw bits of magma into the air. These bits cool into tiny pieces of rock, called volcanic dust or volcanic ash. Wind can carry volcanic dust thousands of miles away. Volcanic ash can coat the land for miles around the volcano.

Steam and poisonous gases also escape from volcanoes. Sometimes these gases are mixed with ash and other hot debris. This mixture travels outward in destructive fiery clouds, called pyroclastic flows.









Crater Lake







ANIMATION 2  (Flash)




  • Lava Hawaii
  • Mount Augustine Alaska
  • Mt St Helens aftermath
  • Mt St Helens
  • Nyiragongo volcano congo
  • Santa Ana Volcano
  • Stromboli Italy
  • Taal Volcano, Luzon, Philippines
  • Volcano smoking
  • volcano
  • Crater Lake Oregon
  • Hawaii lava flow
  • Lava flow




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