(CNN) — Here's some background information about volcanoes, mountains that open downward to a reservoir of molten rock. Facts: More than 80% of the Earth's surface, both above and below sea level, is ...

A dormant volcano in Ethiopia erupted after 10,000 years of silence. This event shows how the world's little-known volcanoes ...

Several hundred volcanoes lie dormant beneath the Eifel in western Germany. They are typical examples of what is known as distributed volcanic fields. To better understand their formation and activity ...

Lava is molten rock from a volcano that reaches the Earth’s surface. Liquid rock below the Earth’s surface is referred to as magma. More than 50% of the world’s active volcanoes above sea level ...