Pacific Ring of Fire. Map of the Pacific hemisphere of the Earth, showing the location of earthquakes (yellow dots) and volcanoes (red triangles) around what is known as the 'Ring of Fire'. The volcanoes and earthquakes are concentrated along the boundaries (red lines) of the tectonic plates that make up the Earth's crust. The large plate at centre is the Pacific Plate. Tectonic plates move over the molten rock below them, colliding with and moving past, under and over each other. Immense pressures can build up, which are released during an earthquake. The Ring of Fire has formed as surrounding plates collide with and destroy the Pacific Plate.