Volcanoes are one of the most impressive geological features around, but the biggest of them all isn't here on Earth, but ...

“Noctis Mons” is the seventh-largest volcano on Mars, the biggest being this one pictured—Olympus Mons (artist's impression). Scientists have discovered a massive, deeply eroded giant shield volcano ...

Deep below the Earth's surface, magma is churning and flowing into the Axial Seamount, an underwater shield volcano about 300 miles off the coast of Oregon. As the volcano grows and tremors increase, ...