Volcanoes are opening in the Earth's crust which hot magma
,ash and gases to escape from below the surface.
Volcano is from the latin word "vulcan". Thought it was an
to hell. Like in Mt.Etna,they believed that Hephaestus,god of fire.
Volcanism is an activity when a volcano erupts at a certain time.
It happens because of the "convection cycle" at the magma that forces
the volcano to erupt.
"Pacific Ring of Fire" is long belt of volcanoes that encircles
the Pacific Ocean. Around 75% of the world's most active volcanoes
are found here. And its where the Philippines almost lies.
There are many volcanoes that have caused great danger like Mt. Paricutin
in Mexico. It erupted in a cornfield of a farmer named Dionisio. On the
first day, it was 40 meters until it came at 100 meters more at the fifth
day. It continued to erupt for 9 years until it stopped.
There is also Mt. Kilauea whose erupted for 50 times, Mt. Vesuvius was
responsible for the destruction of the city of Pompeii and Herculaneum
and Mt. Krakatau affect subsequent collapse in Indonesia.