- The middle of the Pacific Ocean is the volcanic Hawaiian Islands that aren’t connected with any plate boundary normally associated with plate margins.
- The volcanoes are caused by a localised hotspot within the Pacific Plate. The concentrations of radioactive elements inside the mantle cause the hotspot to develop, from this a plume of magma rises to eat into the plate above.
- Where lava breaks through to the surface, active volcanoes occur above the hotspot.
- Hotspot is stationary so as the Pacific plate moves over it a line of volcanoes is created. One above the hotspot is active and the rest form a chain of extinct volcanoes. Hotspots are evidence that the Pacific plate is moving to the North-West.
