A volcano is an opening in a planet or moon's crust through which molten rock, hot gases, and other materials erupt. Volcanoes often form a colina or mountain as layers of rock and ash build up from repeated eruptions.

Volcanoes are classified every bit active, dormant, or extinct. Agile volcanoes have a recent history of eruptions; they are likely to erupt again. Dormant volcanoes have not erupted for a very long time but may erupt at a future time. Extinct volcanoes are not expected to erupt in the futurity.

Within an active volcano is a bedchamber in which molten rock, called magma, collects. Force per unit area builds up inside the magma sleeping room, causing the magma to move through channels in the stone and escape onto the planet'southward surface. Once information technology flows onto the surface the magma is known as lava.

Some volcanic eruptions are explosive, while others occur as a wearisome lava catamenia. Eruptions can occur through a principal opening at the top of the volcano or through vents that course on the sides. The rate and intensity of eruptions, as well as the composition of the magma, determine the shape of the volcano.

Volcanoes are constitute on both land and the ocean floor. When volcanoes erupt on the ocean floor, they frequently create underwater mountains and mountain ranges as the released lava cools and hardens. Volcanoes on the bounding main floor become islands when the mountains become so large they rise in a higher place the surface of the ocean.

Volcanoes

Volcanic eruptions tin can create colorful and dramatic displays, such as this eruption of this volcano in the Virunga Moutains of the Democratic Republic of the Congo.

active volcano

Noun

volcano that has had a recorded eruption since the terminal glacial flow, about 10,000 years ago.

dormant volcano

Noun

volcano that has erupted in the past but is unlikely to erupt shortly.

erupt

Verb

to explode or suddenly eject textile.

lava

Substantive

molten stone, or magma, that erupts from volcanoes or fissures in the World'due south surface.

Noun

molten, or partially melted, rock beneath the Earth's surface.

molten

Adjective

solid material turned to liquid past heat.

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    Director

    Tyson Brown, National Geographic Guild

    Author

    National Geographic Society

    Production Managers

    Gina Borgia, National Geographic Order
    Jeanna Sullivan, National Geographic Society

    Plan Specialists

    Sarah Appleton, National Geographic Society
    Margot Willis, National Geographic Social club

    Last Updated

    April 5, 2019

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