Shallow lithospheric contribution to mantle plumes revealed by integrating seismic and geochemical data

Using an integrated geophysical and geological approach based on a comparative analysis of 27 different parameters, we investigate both the location and origin of the source material for hot spot volcanoes. We report a significant correlation between extreme geochemical compositions of lavas with both shallow seismic velocities and the depth extent to which a hot spot source can be traced with seismic tomography. These relationships provide the first integrated evidence for buoyantly rising plumes of mantle material (plume depth extent correlation), incorporating thermally eroded continental material in the shallow mantle (anti-correlation with slow shallow seismic velocities). The extreme geochemical composition of the lavas is successfully modeled with this process, placing constraints on dynamical processes in the mantle and explaining the origin of a significantly debated mantle compositional end-member (enriched mantle; EM1).