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 ...

Volcanic eruptions are perhaps nature's most terrifying display of power. Catastrophic eruptions of volcanoes like Mount Vesuvius, Krakatoa, and Mount St. Helens have gone down as some of the most ...