Plate Migration Across Mantle Plumes
| Three-dimensional view of an island chain forming. The Hotspot is relatively stationary with lithospheric plate movement over it's position. Figure source: http://pubs.usgs.gov/gip/hawaii/page12.html |
As a lithospheric plate moves over a mantle plume, a chain of volcanoes is created. The volcanoes get older in the direction of plate motion. The Hawaiian mantle plume has created a chain of volcanic islands and seamounts (known as the Hawaiian-Emperor chain) thousands of kilometers long over the past 80 million years. The Hawaiian mantle plume is located beneath the Pacific plate, which is moving to the west-north-west, hence the Hawaiian Islands get older to the west-north-west. Motion of the lithosphere eventually carries a volcano away from the plume and its magma source, so the volcano then becomes extinct. Volcano formation from the fixed mantle plume traces a path of the migrating lithospheric plate.
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