How does a volcano erupt?

A volcano is a hole in the Earth from which molten rock and gas erupt.

The Earth’s crust is made up of huge plates which fit together like a jigsaw puzzle. These plates sometimes move. The space between the Earth’s crust and mantle is made up a substance made up of rocks and gases. When two plates collide, one section slides beneath the other. The lower plate gets pushed dog’ and the substance made up of rocks and gases gets squeezed up between the two plates.

As the pressure in the molten rock builds up it looks for a place to escape to in a way similar to the pressure cooker pushing its whistle up to release pressure. It forces its way upwards through narrow cracks in the earth’s crust. Once this molten rock liquid bursts through these cracks we have an active volcano. Volcanoes work like giant valves to release the pressure built up inside the Earth.