Volcanoes
In plate tectonics, the study of volcanoes
is a fascinating one. Some plate tectonics students only study
volcanoes. The Earth is made of three sections, the crust,
the mantle and the core. The crust is very thin and cool
compared to other parts of the Earth. Underneath the Earth's
crust is the mantle made of very hot soft rock. The soft rock
is called magma. Sometimes the hot magma breaks through a thin
weal part of the crust forming a volcano.
Some volcanoes are not active and stay
dormant doing nothing for hundreds of years. But hot magma can
shoot out of the crater suddenly. This is called erupting. When
a volcano erupts, the hot magma flows out of the Earth's crust,
down the sides of the volcano and becomes hard as it cools. Hot
magma flowing out of the crust is called lava. The hole of the
Earth's crust where the magma broke the surface is called a
crater. Some of the lava contain bubbles of gas and form pumice
when cooled.

Picture of a volcano
erupting
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