The complex European-Adria geodynamic framework, which led to the formation of the Alpine belt, is considered responsible for the orogenic magmatism that occurred in the Central Alps along the Periadriatic/Insubric Line (late Eocene-early Oligocene) and the anorogenic magmatism that occurred in the Southeastern Alps (late Paleoceneearly Miocene). While subduction-related magmatic activities are expected near convergent margins, the presence of the intraplate-related magmatic products is still puzzling. Therefore, in this work new geochemical and geochronological data of magmatic products from the Veneto Volcanic Province (VVP, northeast Italy) are provided in order to constrain the Cenozoic intraplate magmatism of the Southeastern Alps. The VVP is formed by dominant basic-ultrabasic (from nephelinites to tholeiites) magmatic products and by localized acid (latitic, trachytic, and rhyolitic) volcanic and sub-volcanic bodies. Trace element patterns and ratios suggest that the mantle source of the basanitic magma types was a phlogopite-bearing garnet lherzolite, while those of the tholeiitic magma types was an anhydrous (i.e., without residual phlogopite and amphibole) garnet lherzolite. All the basic-ultrabasic VVP magmatic products exhibit enrichments in Ba, Sr, and P, indicating the mantle sources could be metasomatized by carbonatitic melts. According to the biostratigraphic records and our new 40Ar/39Ar ages, VVP eruptions occurred in several pulses, reflecting the extensional phases experienced by the Eastern Alpine domain. The volcanism started in the late Paleocene in the western sector of the VVP where activity was widespread also during the Eocene (45.21± 0.11 Ma-38.73 ± 0.44 Ma). In the eastern sector eruptions took place only in the early Oligocene (32.35 ± 0.09 Ma-32.09 ± 0.29 Ma) and in the early Miocene (~22-23 Ma). Previously, as suggested for neighboring orogenic magmatism, also the anorogenic magmatic activities were interpreted as resulting from mantle upwellings through slab window(s) following the European slab break-off occurred~35 Ma. However, considering i) new tomographic images evidencing a continuous subvertical slab beneath the Central Alps, and ii) the onset of magmatic activity in the VVP in the late Paleocene (i.e., before the slab break-off) and its continuation until Miocene, we propose an alternative geodynamic scenario to explain the anorogenic magmatism. The westward rollback of the European slab caused the retreat and steepening of the sinking plate. As a consequence, the sub-slab mantle material escaped and upwelled from the front of the slab and created a poloidal mantle flow. The latter induced the breakdown of carbonates in calcareous metasediments and carbonated metabasics within the subducting oceanic slab, providing carbonatitic melts, which could be responsible for the metasomatism of the VVP mantle sources. After that, the poloidal mantle flow also induced i) the extensional deformation in the overriding Adria microplate and ii) the decompressional melting of VVP mantle ...

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