“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, ...

Volcanoes can look like small mountains or hills. A volcano is an opening in the Earth's crust that allows magma, hot ash and gases to escape. Composite volcanoes are the most common type of volcano.