Volcanoes Facts for Kids
Explosive facts about volcanoes and geology
Many volcanoes form where one tectonic plate dives beneath another in a process called subduction. As the plate sinks into the hot mantle, it releases water that lowers the melting point of surrounding rock, generating magma that rises to form volcanoes.
Volcanoes are classified as active (erupted recently or likely to), dormant (not erupting now but could in future), or extinct (unlikely to erupt again). However, some 'extinct' volcanoes have surprised scientists by waking up again.
Cotopaxi in Ecuador is one of the world's highest active volcanoes, rising to nearly 19,400 feet above sea level. It is also one of the most dangerous, since eruptions could melt its icy summit glacier and send devastating mudflows toward the capital Quito.
The black sand beaches found in Iceland, Hawaii, and the Canary Islands are made entirely from volcanic basalt rock that has been ground down by ocean waves. The sand actually sparkles because it contains tiny mineral crystals.
Magma doesn't always reach the surface. It can force its way into cracks in existing rock and solidify underground, forming flat sheets called sills (horizontal) or dikes (vertical). These structures are later exposed by erosion millions of years later.
Mount Aso in Japan contains one of the world's largest active calderas, measuring about 15 miles across. About 50,000 people actually live inside the caldera, farming the incredibly fertile volcanic soil.
Volcanologists sometimes wear special heat-resistant suits and use drones to approach active lava flows and craters. In 1993, a sudden steam explosion at Galeras volcano in Colombia killed six scientists who were conducting research inside the crater.
The Reykjanes Peninsula in Iceland entered a new volcanic era in 2021 after nearly 800 years of inactivity. By 2024, multiple eruptions had destroyed roads and forced the evacuation of the town of GrindavΓk several times.
Large globs of lava hurled into the air by explosive eruptions are called volcanic bombs. They spin through the air and cool into aerodynamic shapes before landing β some the size of a car β up to several miles from the vent.
Papakolea Beach on Hawaii's Big Island is one of only four green sand beaches in the world. The green color comes from olivine, a volcanic mineral that makes up much of Earth's upper mantle and is one of the most abundant minerals on the planet.