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 ...

Add Yahoo as a preferred source to see more of our stories on Google. Magma becomes lava when it rises up to the Earth’s surface, like when the Nyiragongo volcano erupted in the Democratic Republic ...

Gold and other precious metals are leaking from Earth’s core into the layers above, eventually making their way up to the surface during the formation of volcanic islands like Hawaii, a new study ...

The geochemistry of agate and chalcedony in volcanic rocks represents an intricate record of silica precipitation and crystallisation processes occurring under variable thermal and chemical conditions ...

Scientists say they've discovered a 400-mile chain of extinct and fossilized volcanoes beneath southern China. The volcanoes, the researchers claim, were likely formed when two major tectonic plates ...