Welcome to CoreFacts, where we're always short on time and
big on science. I'm Jessica Robertson. Today we have a pretty straight forward
question.
What is a volcano?
Volcanoes are mountains, but they are very different from
other mountains. They are not formed by folding and crumpling or by uplift and
erosion. Instead, volcanoes are built by the accumulation of their own eruptive
products—lava, bombs, ashflows, and tephra—which is airborne ash and dust.
A volcano is most commonly a conical hill or mountain built
around a vent that connects with reservoirs of molten rock below the surface of
the Earth. The term volcano also refers to the opening or vent through which
the molten rock and associated gases are expelled.
And now you know. Join us again every weekday for a new
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