(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 ...

Fluid inclusions in volcanoes are dominantly composed of carbon dioxide. At magmatic temperatures — 2,192 degrees — the density of the carbon dioxide strongly depends on pressure, which is influenced ...

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 ...

Add Yahoo as a preferred source to see more of our stories on Google. When you think of the United States, images of sprawling cities and vast landscapes might come to mind, but not the hidden and ...

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.

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 ...