Hot Spot

A hot spot is a site of persistent intraplate volcanism fed by a deep mantle plume that stays roughly fixed while the overriding plate moves across it. The plate motion records the track as a chain of progressively older volcanoes, dead seamounts and guyots downstream, an active volcano above the plume. The Hawaiian-Emperor chain is the type example: its 47-million-year-old bend marks a change in Pacific plate direction, and ages increase northwest from Kilauea at a rate matching plate velocity near 8 to 10 cm/yr. Hot spots build oceanic islands, seamount chains, and, where output is large, oceanic plateaus.