Volcanoes

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Volcanoes
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What is a volcano?
Volcanoes are really mountains that build taller
and taller, with time, as they erupt. That means
that molten rock, magma, comes from inside the
earth and erupts onto the surface. The volcano
might be explosive and produce ashes or be
effusive and produce lava. The explosions are
usually first because there are lots of gases
inside the magma. Most volcanoes are 10,000 to
100,000 years old it takes time for them to
grow big.
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What causes a volcano

• Inside the earth's core there is a red-hot liquid
  rock, called magma.
• Volcanoes happen when magma rises to the surface
  of the earth, which causes bubbles of gas to
  appear in it.
• This gas can cause pressure to build up in the
  mountain, and it eventually explodes. When the
  magma bursts out of the earth, it is called lava.

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lava

• Magma is liquid rock inside a volcano.
• When magma comes to the surface it becomes Lava.
• Lava flows out of a volcano at 700 to 1,200 C
  in temperature and glows red hot to white hot as
  it flows.

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Volcanic Eruptions

• Volcanoes can change the weather. They can cause
  rain, thunder and lightning. Volcanoes can also
  have long-term effects on the climate, making the
  world cooler.
• Fast-moving lava can kill people and falling ash
  can make it hard for them to breathe. They can
  also die from famine, fires and earthquakes which
  can be related to volcanoes. volcanoes can
  destroy houses, roads and fields.
• Lava can kill plants and animals too. The Mount
  St Helens volcano in 1980 killed an estimated
  24,000 animals

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This is a diagram of all the parts of a volcano.
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By Bailey.