What are Volcanoes

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Volcanoes are big bumpy mountains with a vent that leads down to the Earth's core (centre of the Earth). They erupt when the pressure in the core is to much and the magma (lava in the Earth) tries to find a way out. If we had no volcanoes the Earth would probably explode!

How are volcanoes Formed

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Deep down in the core (center of Earth) pressure builds up, then needs to find a way out, it pushes through the mantle (under the layer we walk on) and it finds a way to get through the crust ( the layer we walk on). When the pressure find a way out, it explodes in a volcanic eruption.  The ash settles on the side of the mountain with the lava  then hardens and becomes rock.  The mountain grows after each  eruption.  

Types Of Volcanoes

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There are many types of volcanoes.  Some of them are Caldera, Shield, Strato  (composite) ,Cinder cone  and Lava Dome.  A Caldera is a volcano that's crater (around the vent ) collapses and usually water collects in it likeTaupo Lake. A Shield volcano is usually formed under water,  when it erupts it  cools quicky  forming Islands.   Shields are not that explosive.  A Strato or compisite  volcano is one with multiple vents.  A Cinder cone is the simplest  with only one vent.  A Lava Dome is when Lava gets stuck in the top of the vents and hardens trapping air,  the pressure gets so much  that it explodes in a very explosive eruption.     

Types Of Eruptions

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There are different types of volcanic eruptions.   It depends on how much of  what they consist of.  One type of eruption has more pyroclastics ( fragments of rock)  than ash and lava called Strombolian.  Hawaiian has more lava than pyroclastics.  Pelean eruptions are more ash than pyroclastics.       

Conclusion

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Some people are scared of Volcanoes when they explode. People might think the world is trying to kill them. But if there was no Volcanoes the Earth would explode. There are may types of Volcanoes and eruptions. They can kill you but they are not trying to.