Volcanoes

What are volcanoes?

A Volcano is a gap in the earth where molten rock and other materials come to the earth's surface. Some volcanoes are just cracks in the earth's crusts. Others are weak places in the earth's crust, which occur on places where magma bubbles up through the crust and comes to the earth's surface. Magma is molten rock that occurs by partial melting of the crust and the mantle by high temperatures deep down in the ground. Once magma comes to the earth's surface it is called lava.
Active and non-active volcanoesThere are volcanoes in different phases of activity:Active volcanoes, which are likely to erupt at any moment, dormant volcanoes, which lie dormant for centuries, but then erupt suddenly and violently, and extinct volcanoes - ones no longer likely to erupt.