A volcano is a landform (usually a
mountain) where molten rock erupts through the surface of the planet.
In
simple terms a volcano is a mountain that opens downward to a pool of
molten rock (magma) below the surface of the earth. It
is a hole in the Earth from which molten rock and gas erupt. Did
you know? The name "volcano" has its origin from the
name of Vulcan, a god of fire in Roman mythology. As
pressure in the molten rock builds up it needs to escape somewhere. So
it forces its way up "fissures” which are narrow cracks
in the earths crust. Once the magma erupts through the earth’s surface
it’s called lava. |
Magma
is liquid rock inside a volcano. Lava is liquid
rock (magma) that flows out of a volcano. Fresh lava ranges from 1,300°
to 2,200° F (700° to 1,200° C) in temperature and glows red hot to white
hot as it flows.
There are around
1510 'active' volcanoes in the world. We currently know of 80 or more
which are under the oceans. - Crust
The
crust is the outer layer of Earth. It is about 18 miles thick. It is
the part we live on. - Mantle
The second
layer is called the mantle. It is about 1,800 miles thick. - Core
The
inner layer is called the core.
The Earth's crust is made up of
huge slabs called plates, which fit together like a
jigsaw puzzle. These plates sometimes move. Between the Earth's
crust and the mantle is a substance called magma which
is made of rock and gases. When two plates collide, one section
slides on top of the other, the one beneath is pushed down. Magma
is squeezed up between two plates. Did you know? Volcanoes are
like giant safety valves that release the pressure that builds up
inside the Earth. |
When
magma erupts through the earth's surface it is called lava
Over half of the world’s volcanoes arise in a
belt around the Pacific Ocean called the Ring of Fire.
Volcano
Eruptions Largest
active volcano Volcanoes around the World
Each triangle on the
map represents a volcano. Volcano FAQ's -- Learn About Volcanoes
What is a
volcano? ... Why do volcanoes erupt? ... Where do volcanoes erupt? ...
How hot is a volcano? Information on Volcanoes including volcanoes and climate | 
