Lava Volvanoes is a type of molten rock expelled
by a volcano during an eruption. This molten rock is formed in the
interior of some planets, including Earth, and some of their satellites.
When first erupted from a volcanic vent, lava is a liquid at
temperatures from 700 °C to 1,200 °C (1,300 °F to 2,200 °F). Up to
100,000 times as viscous as water, lava can flow great distances before
cooling and solidifying because of its thixotropic and shear thinning
properties.
A lava flow is a moving outpouring of lava, which is created during a
non-explosive effusive eruption. When it has stopped moving, lava
solidifies to form igneous rock. The term lava flow is commonly
shortened to lava. Explosive eruptions produce a mixture of volcanic ash
and other fragments called tephra, rather than lava flows. The word
"lava" comes from Indonesia and Italian, and is probably derived from
the Latin word labes which means a fall or slide.
Lava is molten rock that spews from an erupting volcano. It is extremely
hot, reaching temperatures as high as 1,300 to 2,000 degrees Fahrenheit
(704 to 1093 degrees Celsius). In a volcanic eruption, lava is in
liquid form. When it solidifies, it forms igneous rock.
However, it can take quite a long time to cool, traveling great
distances before becomes solid. Molten rock is not always called lava.
Before a volcano erupts and molten rock is still underground, it is
called magma. Besides being a little cooler, molten rock is not
dramatically different once it's above ground. The distinction between
magma and lava is basically made to make geological occurrences easier
to understand and explain.
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