(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 ...

Most volcanoes form at the boundaries of Earth's tectonic plates, which are huge slabs of crust and upper mantle that fit together like puzzle pieces. Think of these plates as massive rafts floating ...

Mount Etna's strange lava has long perplexed scientists, but new research reveals that the volcano formed in a bizarre way — ...

About 290 miles off the coast of Cannon Beach, Oregon, lies an underwater volcano called Axial Volcano. Axial erupts about once every ten years. Twice in the past year, news outlets have reported that ...

Add to the long list of global warming concerns that melting ice caps could trigger more volcanic eruptions. Worse, researchers said Monday at a scientific conference in Prague, the increasing ...

Volcanoes in Alaska, Washington state, Oregon and Hawaii have been rumbling and even spewing lava, enough to spark a swarm of news stories. But despite the jolts and temblors, geologists say there's ...

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 ...