(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 ...

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 ...

Here’s a look at volcanoes, mountains that open downward to a reservoir of molten rock. More than 80% of the Earth’s surface, both above and below sea level, is of volcanic origin. Lava is molten rock ...

Add Yahoo as a preferred source to see more of our stories on Google. Volcanoes are Earth’s special effects department, constantly proving that reality can be more dramatic than Hollywood. Lava flows ...

May 6 (Reuters) - A volcano dormant for thousands of years is erupting in the remote South American region of Patagonia, coating nearby towns in ash and forcing emergency evacuations -- the latest in ...