A mantle plume is an upwelling of abnormally hot rock within the Earth's mantle. As the heads of mantle plumes can partly melt when they reach shallow depths, they are thought to be the cause of volcanic centers known as hotspots and probably also to have caused flood basalts. It is a secondary way that Earth loses heat, much less important in this regard than is heat loss at plate margins (see Plate tectonics). Some scientists think that plate tectonics cools the mantle, and mantle plumes cool the core.
The geometry of the Hawaiian-Emperor seamount chain and the regular progression of ages of volcanism along it were taken as important evidence in support of the mantle plume theory (Morgan, 1972 and Willson, 1963).
