What cause volcano to eurption?

Answer 1

Volcanoes erupt due to the build up of magma (rocks are cooled magma which is made liquid by intense heat) in the Earth's crust below the place they erupt. This is called seismic activity.

Some types of volcanoes are:

New ones which erupt sometimes after other thermal activity becomes apparent sometimes unexpectedly but usually in an area where there are other volcanoes or thermal activity.

An example is the Volcanic Plateau in New Zealand which is part of the Pacific Rim of Fire where many extinct, dormant and active volcanoes are situated.

Other volcano types are:

extinct, nothing happening for a very long time

dormant, they have not erupted for a long time but might become active in 500-1000 years

active, they 'dribble or spew' all the time

Answer 2

Volcanoes erupt due to the build-up of pressure beneath the Earth's surface from the accumulation of magma. When this pressure becomes too great, it forces the magma to escape through vents in the volcano, resulting in an eruption. Factors such as the composition of the magma, the presence of gases, and tectonic activity can all contribute to volcanic eruptions.