(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 ...

This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated. (KTXL) — California is known for its beaches ...

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 ...