000K utf8 1100 $c2020 1500 eng 2050 urn:nbn:de:gbv:8:3-2021-00126-5 2051 10.1029/2020GC008993 3000 El-Sharkawy, Amr 3010 Behrmann, Jan Hinrich 3010 Cristiano, Luigia 3010 Hamada, Mona 3010 Köhn, Daniel 3010 Lebedev, Sergei 3010 Meier, Thomas 3010 Weidle, Christian 4000 The Slab Puzzle of the Alpine-Mediterranean Region$dInsights from a new, High-Resolution, Shear-Wave Velocity Model of the Upper Mantle [El-Sharkawy, Amr] 4209 Mediterranean tectonics since the Lower Cretaceous has been characterized by a multiphase subduction and collision history with temporally and spatially variable, small ‐ scale plate con fi gurations. A new shear wave velocity model of the Mediterranean upper mantle (MeRE2020), constrained by a very large set of over 200,000 broadband (8 – 350 s), interstation, Rayleigh wave, phase velocity curves, illuminates the complex structure and fragmentation of the subducting slabs. Phase velocity maps computed using these measurements were inverted for depth ‐ dependent, shear wave velocities using a stochastic particle ‐ swarm ‐ optimization (PSO) algorithm. The resulting three ‐ dimensional (3 ‐ D) model makes possible an inventory of slab segments across the Mediterranean. Fourteen slab segments of 200 – 800 km length along ‐ strike are identi fi ed. We distinguish three categories of subducted slabs: attached slabs reaching down to the bottom of the model; shallow slabs of shorter length in downdip direction, terminating shallower than 300 km depth; and detached slab segments. The location of slab segments are consistent with and validated by the intermediate ‐ depth seismicity, where it is present. The new high ‐ resolution tomography demonstrates the intricate relationships between slab fragmentation and the evolution of the relatively small and highly curved subduction zones and collisional orogens characteristic of the Mediterranean realm. 4950 https://doi.org/10.1029/2020GC008993$xR$3Volltext$534 4950 https://nbn-resolving.org/urn:nbn:de:gbv:8:3-2021-00126-5$xR$3Volltext$534 4961 https://macau.uni-kiel.de/receive/macau_mods_00000993 5051 550 5550 Mediterranean upper mantle 5550 Particle Swarm Optimization 5550 slab fragmentations 5550 slab gaps and tears 5550 surface wave tomography