Deadliest volcanic eruption: The 1815 eruption of Mount Tambora in Indonesia, which killed up to 100,000 people From lava fountains to towering ash clouds, volcanoes produce some of the most dramatic ...

(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 ...

ANCHORAGE, Alaska — A volcano near Alaska’s largest city is showing new signs of unrest, with experts saying the likelihood of an eruption at Mount Spurr in the next few weeks or months has increased.

More than 1,400 volcanoes dot the Southwestern United States. At least three erupted in the past 1,000 years, which is practically yesterday in geologic time. Experts and disaster officials are ...

When the crew aboard the research vessel Sonne set out on a cruise last spring, they were expecting a routine mapping expedition in the South Pacific. But they were in for a big surprise. They ended ...

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 ...

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 ...