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Abstract

Mantle plumes - or areas of focused upwelling of hot and possibly compositionally-heterogeneous material from the base of the mantle to the surface - are features that were first predicted by the physics of mantle convection. Although they have been invoked as the primary origin for hotspot tracks, their existence has long been disputed due to the lack of direct observations. Even now that we have seismic tomography images of mantle plumes, notably thanks to the development of full-waveform inversions, there are still many unknowns about mantle plumes. For instance, we still do not know with precision where and how mantle plumes originate, what is their composition, their geometry and their dynamics, and how they interact with the surrounding mantle. In this presentation, we propose to give an overview of the recent advances in unravelling mantle plume properties and geometry. We will show, with the help of geodynamic models of whole-mantle convection, how a mantle plume behaviour can be affected by both its rheology and its interactions with other mantle heterogeneities, therefore providing some ways to better constrain mantle plume properties and dynamics.