The Samoa hotspot is a volcanic hotspot located in the south Pacific Ocean.
The hotspot model describes a hot upwelling plume of magma through the Earth's crust as an explanation of how volcanic islands are formed. The hotspot idea came from J. Tuzo Wilson in 1963 based on the Hawaiian Islands volcanic chain.
Mt Matavanu eruption on Savaiʻi island, 1905.
In geology, hotspots are volcanic locales thought to be fed by underlying mantle that is anomalously hot compared with the surrounding mantle. Examples include the Hawaii, Iceland, and Yellowstone hotspots. A hotspot's position on the Earth's surface is independent of tectonic plate boundaries, and so hotspots may create a chain of volcanoes as the plates move above them.
Diagram showing a cross section through Earth at the Hawaii hotspot. Magma originating in the mantle rises into the asthenosphere and lithosphere. A chain of volcanoes is created as the lithosphere moves over the source of magma.
Over millions of years, the Pacific Plate has moved over the Hawaii hotspot, creating a trail of underwater mountains that stretches across the Pacific.
Kilauea is the most active shield volcano in the world. The volcano erupted from 1983 to 2018 and is part of the Hawaiian–Emperor seamount chain.
Mauna Loa is a large shield volcano. Its last eruption was in 2022 and it is part of the Hawaiian–Emperor seamount chain.