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As you can see in Figure 9, hot molten rocks called magma is stored in a
big reservoir called the magma chamber. Sometimes, the magma nds its way
through a crack, creates an opening at the surface of the earth and erupts.
During an eruption, the magma comes out of the earth, ows as lava and gives
birth to a volcano.
After many eruptions, a volcanic cone is built up. Inside the volcanic cone,
a chimney-like column is formed. It is known as a pipe. When a volcano erupts,
magma rises through the pipe, comes out of the crater and ows down its slopes.
On cooling down, the lava solidies to become basalt rocks.
Volcanoes can become mountains or hills /mounts.
Lava ows can form large volcanic plains or plateaus.
Let’s find out what happens when volcanoes erupt on land.
Let’s learn more about volcanoes
Magma
Magma
reservoir
Pipe
Lava flow
Crater
Volcanic
cone
2.4 volcanoes
fig. 9 a volcano in eruption