Volcano - Wikipedia
网页A volcano is a rupture in the crust of a planetary-mass object, such as Earth, that allows hot lava, volcanic ash, and gases to escape from a magma chamber below the surface. The process that forms volcanoes is called volcanism.
Volcanoes - National Geographic Society
网页2023年10月19日 · 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 hill or mountain as layers of rock and ash build up from repeated eruptions. Volcanoes are classified as active, dormant, or extinct.
About Volcanoes | U.S. Geological Survey - USGS.gov
网页Volcanoes are openings, or vents where lava, tephra (small rocks), and steam erupt onto the Earth's surface. Volcanic eruptions can last days, months, or even years.
Volcano | Definition, Types, & Facts | Britannica
网页2024年8月27日 · Volcano, vent in the crust of Earth or another planet or satellite, from which issue eruptions of molten rock, hot rock fragments, and hot gases. The term volcano can also refer to the landform created by the accumulation of solidified lava and volcanic debris near the vent.
List of the world’s major volcanoes | Locations & Facts
网页There are more than 1,500 potentially active volcanoes or volcanic areas around the world at any given time. They may be the world’s most dynamic landforms, given their ability to grow by accretion or shatter and collapse during an eruption.
Volcano facts and information - National Geographic
网页2018年1月15日 · Volcanoes are Earth's geologic architects. They've created more than 80 percent of our planet's surface, laying the foundation that has allowed life to thrive. Their explosive force crafts...
Volcano facts and types of volcanoes - Live Science
网页2022年3月3日 · A volcano is an opening in Earth's crust where magma breaks through, and when erupting can rain down molten rock, ash and gases. There are several types of volcanoes.
What Is a Volcano? | NASA Space Place – NASA Science for Kids
网页2024年9月17日 · Volcanoes occur when material significantly warmer than its surroundings is erupted onto the surface of a planet or moon from its interior. On Earth, the erupted material can be liquid rock ("lava" when it's on the surface, "magma" when it's underground), ash, cinders, and/or gas.
Volcanoes and Volcanic Eruptions - Facts and Information
网页A volcano is a vent in Earth's surface where magma, gas, and ash escape. The name is also used for cones of erupted material at the vent. Volcanoes are found on many planets and moons in our solar system.
What is a volcano? - Internet Geography
网页2024年8月22日 · A volcano is a conical hill or mountain formed by material from the mantle being forced through an opening or vent in the Earth’s crust. Volcanoes have vents or openings that provide direct access to lava and gases stored below the Earth’s surface and can release these elements into the atmosphere.