A volcano begins as magma or melted rock inside
the earth. The Magma inside the Earth is hot enough to burn through the
rock inside the earth. Nobody really knows how a volcano is formed itís a
phenomenon of the world.
volcanoes erupt is there gas filled chambers full of magma gets
under great pressure from the solid rock around it.When to much pressure is
against the† gas filled chamber it
melts through a fractured part of the rock and blast out.