This region of great volcanic activity rings the Pacific Ocean. The Pacific tectonic plate, which lies under most of the ocean, meets several other plates at its edges.
These tectonic plates are moving very, very slowly. Where the plates meet, they collide or slide past each other. The result is earthquakes and volcanoes.
Most volcanoes and earthquakes occur in an area that rings the Pacific Ocean. Volcanoes and earthquakes happen in other places, too, but they are most common in this area, called the ring of fire.
The ring of fire lines the coastal lands and waters of New Zealand, Papua New Guinea, Indonesia, the Philippines, Japan, the Kamchatka Peninsula of Russia, the Aleutian Islands, and western North and South America.