Crust and upper mantle of the western Mediterranean - Constraints from full-waveform inversion

•Full-waveform tomographic model of the western Mediterranean crust and mantle.•Incorporation of body and multi-mode surface waves in the period range from 12-150 s.•No mantle plumes present beneath the European Cenozoic rift system.•First detection of African slab around 200-300 km depth beneath Algerian coast.•African slab detached from the surface and broken into two segments.

We present a full-waveform tomographic model of the western Mediterranean crust and mantle constructed from complete three-component recordings from permanent and temporary networks. The incorporation of body and multi-mode surface waves in the period range from 12-150 s allows us to jointly resolve crustal and mantle structures, including the Guadalquivir, Tajo and Ebro basins at shallow depth, as well as the western Mediterranean subduction system in the transition zone. No mantle plumes can be detected beneath the European Cenozoic rift system, including the Massif Central. In addition to the well-studied Alboran slab, a strong E-W trending high-velocity anomaly is present around 200-300 km depth beneath the Algerian coast. This previously undetected African slab is detached from the surface and broken into two segments. It may be interpreted as the slab that caused the opening of the Liguro-Provençal basin through successive roll-back between 35-15 Ma.