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Volcanoes are really mountains that build taller and taller, with time, as they erupt. That means
that molten rock, magma, comes from within 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.
When you have a bottle of soda pop, you do not see any bubbles of gas, but when you open it, bubbles form almost instantly.
Once the gas bubbles have all escaped, the soda is flat. Once the magma is flat, a lava flow comes out. Most of the volcanoes
from around the Pacific Ocean are composite, which means that there are layers of ashes and lava. Most volcanoes are 10,000
to 100,000 years old — it takes time for them to grow big.
The possible topics for Volcanoes are:
1. Intrusive activity
2. Types of magma
3. Types of Volcanoes
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