Hot lava flowing down the side of an erupting volcano. Getty Images

Hot lava flowing down the side of an erupting volcano. Getty Images

Liquid magma is called lava when it pours out of a volcano. Getty Images

Liquid magma is called lava when it pours out of a volcano. Getty Images

When a volcano erupts

An exploding volcano throws lava, gas and ash into the air. The liquid magma, which is melted rock, starts its journey upwards through the volcano from a magma chamber, or lake, deep inside the earth.

Magma is hot fluid melted rock below the earth's crust.

Magma reaches the surface through the vertical main pipe of a volcano. It is forced up by pressure from deep inside the earth. When it comes out of the earth's surface it is called lava.

The lava pours out of the hole or vent, at the surface of the volcano. A vent can be at the top or sides of a volcano.

Different kinds of volcano

Mayon volcano in the Philippines is a cone volcano

Mayon volcano in the Philippines is a cone volcano

Cone volcano

A cone volcano is made up of layers of hardened lava and ash, built up each time the volcano erupts.  

Cone volcanoes are triangle-shaped and most have one crater at the top.

 

Taal volcano in the Philippines is a crater volcano

Taal volcano in the Philippines is a crater volcano

Crater volcano

A crater volcano is formed when a cone volcano collapses into the magma chamber, forming a caldera. When the volcano next erupts a new cone is formed, in the middle of the caldera. Sometimes, the caldera fills with water, forming a caldera lake.

Shield volcano

Erta Ale is a shield volcano in Ethiopia (Africa) Getty Images

Erta Ale is a shield volcano in Ethiopia (Africa) Getty Images

Another kind of volcano is a shield volcano, which is built almost entirely of fluid lava flows. Flow after flow pours out of the volcano's vent or vents in all directions, to build a broad, gently sloping cone.

From the side the volcano looks like a warrior's shield, which is how it got the name. 

 

Other interesting facts

  • There are volcanoes under the ocean and under the icecaps.

  • They can also form in hotspots on Earth. Hawaii is an example of a hotspot.

 

Watch a video:

Explore geography games on volcanoes at NeoK12  

Read more about different kinds of volcano:

http://pubs.usgs.gov/gip/volc/types.html

Read a list of the world's volcanoes arranged in height from tallest to smallest

https://en.wikipedia.org/wiki/List_of_volcanoes_by_elevation

Read the kidcyber page: 

Tectonic plates