Plateaus &

volcanoesCreated by Saranya, Sanya,

Sharanya, Shrey and Shreyashi

VolcanoesA volcano is an opening, or rupture, in a planet's surface or crust, 

which allows hot magma, volcanic ash and gases to escape from below the surface. Basically there are three types of volcanoes :-

Active volcanoes  Dormant volcanoes Extinct volcanoes

An erupting volcano

Even though there are at least three main types of volcanoes they have similar interioructures.

• The Crater sometimes called the vent is the mouth of the volcano where the lava and gases escape during an eruption.

• The Volcanic Neck or Shaft is the main conduit where magma rises through the volcano form the lower storage chamber.

• The Sill is where magma cuts between layers of pre-existing rock in the volcano.

• A Dike is where magma cuts across layers of pre-existing rock.

Structure of an volcano

Types of volcanoes    Volcanoes are found in three states -

extinct, dormant and active. An extinct volcano will never erupt again. A dormant volcano has not erupted in 2000 years. An active volcano has erupted recently and is likely to erupt again.

Nevado del Ruiz, an active volcano

Mt fujiyama, an dormant volcano

Mt Kilimanjaro, an extinct volcano

Facts on volcanoes• The name "volcano" has its origin from the name

of Vulcan, a god of fire in Roman mythology.•  The volcanic rock pumice is the only rock that

can float in water. It is usually grey and full of bubbly holes, which form when hot gases jet furiously out of the rock as it cools

•  Volcanoes can grow. As lava and ash accumulate, they add layers and height to the volcanic surface.  This is one common way mountains are built