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[1] Following the diachronous Cretaceous-Neogene onset of seafloor spreading in the northern Atlantic and Arctic oceans, the European passive margin and continental Europe underwent a generalized uplift. This long-wavelength Cenozoic uplift has been attributed either to mantle plumes and/or to the farfield compression in the Alps. We suggest an alternative mechanism or concause, where the asthenosphere depleted at the Mid-Atlantic Ridge was shifted relatively eastward beneath the continent because of the net rotation of the lithosphere. The partial melting at the oceanic ridge leaves the asthenosphere lighter. When migrating beneath the European continental lithosphere, the substitution of the older, denser mantle with the depleted, lighter asthenosphere should have generated an isostatic rebound and associated uplift of about 300-600 m. Dynamic topography exerted by the mantle flowing eastward could have enhanced the uplift process. Citation: Carminati, E., M. Cuffaro, and C. Doglioni (2009), Cenozoic uplift of Europe, Tectonics, 28, TC4016, doi: 10.1029/2009TC002472.

[1] The kinematics of plates is defined by Euler pole and angular velocity. However, during their journey, plates may be affected by additional simultaneous rotations (i.e., subrotations) while they are rotating about their Euler poles. The kinematic description of this particular plate motion requires a different analytical approach: two angular velocities and two poles are necessary to completely describe plate displacements. If a subrotation occurs, none of the points on a plate moves along circles of the Euler pole but, instead, follows cycloid trajectories because of the combination of the two simultaneous rotations. Regardless of the forces that move the lithosphere, every time a plate experiences a subrotation, an additional force (or resisting) force could act on the plate, generating the two-rotation motion. In the hot spot reference frame, we applied this model to the North America plate, investigating its past motion for a time interval [DELTA]t = 43 Ma up to the present and comparing results with those obtained by Gordon and Jurdy (1986). This application shows how the different positions of the North America plate over most of the Cenozoic can be reconstructed by two-rotation plate kinematics.

[1] The topography of ocean ridges and rifts show a distinct asymmetry. The eastern sides of the East Pacific Rise, the Mid-Atlantic Ridge, and the NW Indian Ridge are, on average, 100-300 m more elevated than the conjugate flank to the west. The asymmetry is maintained when bathymetry is plotted versus the square root of crustal age. A comparable topographic asymmetry occurs in the Red Sea and Baikal rifts where the 'eastern' continental shoulders are more elevated. We suggest that depleted and lighter asthenosphere generated below the ocean ridge was shifted 'eastward' relative to the lithosphere, determining a density deficit below the eastern flank. The eastward migration of the lighter Atlantic asthenosphere below the African continent could eventually have contributed to the anomalous postrift uplift of Africa. This model suggests that the 'westward' drift of the lithosphere relative to the underlying mantle might be a global phenomenon. INDEX TERMS: 8155 Tectonophysics: Plate motions--general; 8120 Tectonophysics: Dynamics of lithosphere and mantle--general; 8109 Tectonophysics: Continental tectonics--extensional (0905); 8150 Tectonophysics: Plate boundary--general (3040); 9305 Information Related to Geographic Region: Africa; KEYWORDS: rift asymmetry, bathymetry, lithosphere, asthenosphere, westward drift, continental uplift. Citation: Doglioni, C., E. Carminati, and E. Bonatti, Rift asymmetry and continental uplift, Tectonics, 22(3), 1024, doi:10.1029/2002TC001459, 2003.

The Apenninic foreland displays two exclusive structural signatures, relative to the Puglia region and the Central Adriatic sea, that are indicative of the Apenninic subduction resulting from thick continental lithosphere buckling. The subduction hinge rollback starts in the middle Pleistocene period. Mesozoic rifting induces distortions in the Adriatic plate and varying thicknesses in the lithosphere and continental crust, thus accounting for the distinct dip of subduction and lower elevation in the southern Apennines than in the central-northern Apennines.

The Vettore–Bove normal fault system in central Italy ruptured during the 2016 MW 6.5 Norcia earthquake causing extensive surface faulting. At the Pian Grande di Castelluccio hanging wall basin, along the southern section of the fault ruptured during the MW 6.5 mainshock, we performed a high‐resolution seismic reflection/refraction experiment aimed at (a) imaging the shallow pattern of the fault system, and (b) reconstructing the architecture of the continental infill. We collected three profiles for a total length of ∼8 km. We used a reflection processing flow and non‐linear refraction tomography to obtain migrated stack sections and P‐wave velocity images resolved down to the depth of the pre‐Quaternary substratum. The main profile in the northern part of the basin crosses the westernmost splays of the ruptured fault zone striking N150°–170°. Seismic imaging unravels a ∼1 km‐wide fault zone comprising three W‐throwing splays and subsidiary faults, which affect the continental infill and produce a minimum aggregate Quaternary throw of ∼400 ± 100 m. Recent deformation is localized in this part of the surveyed fault section, attesting active displacement accumulation of the Vettore–Bove fault system. The other profiles in the central‐southern part of the basin show additional faults, likely striking N20°–40° and which concurred to generate a ∼500 m‐deep depocenter. These faults were mostly active during an early extensional phase; however, one of them likely displaces shallow layers with a throw close to the resolution limit of seismic data (<10 m), suggesting activity in the Late Pleistocene. Key Points: Three high resolution seismic profiles image the hanging wall of southern part of the 2016 MW 6.5 central Italy earthquake fault zoneThe surveyed ∼1 km‐wide hidden fault section displays three active W‐dipping splays with a minimum aggregate Quaternary throw of ∼400 mP‐wave velocity tomographic images and migrated sections depict a ∼500 m‐deep Quaternary depocenter in the earthquake fault hanging wall [ABSTRACT FROM AUTHOR]

[1] The deep structure of the southern Apennines (SA) accretionary wedge is still debated since industrial seismic reflection and well data provide reliable constraints only to a depth of about 10 km. As a consequence, two directly linked questions regard (1) the shortening in the accretionary prism (particularly within the buried Apulian thrust units) and (2) the degree of involvement of the lower plate basement (i.e., the Apulian crystalline basement). To address these issues, we have constructed a regional section along a recently released deep seismic reflection profile (CROP-04) which intersects the entire SA. The resulting cross section, adequately constrained to a depth of about 15 km, has been framed in a geodynamic scenario characterized by the eastward roll-back of the westward subducting Apulo-Adriatic lithosphere. On the basis of this section we speculate on the deep structure, building both thin- and thick-skinned thrust models. A cross-check of these end-members models against documented tectonic, geophysical, and geochemical features shows that the thin-skinned model is generally more consistent with the available data. The development of basement slices with thicknesses of tens of kilometers is unlikely, while it remains possible that the Apulian basement could have been involved with its upper few kilometers. In the thin-skinned model, the total shortening of the allochthonous units (i.e., Apennine and Apulian carbonate platforms and Lagonegro basin) is estimated to be greater than 280-300 km. Some 90 km of shortening can be attributed to the Apulian thrust units. Citation: Scrocca, D., E. Carminati, and C. Doglioni (2005), Deep structure of the southern Apennines, Italy: Thin-skinned or thick-skinned?, Tectonics, 24, TC3005, doi:10.1029/2004TC001634.

[1] Along representative cross sections of the Apennines and the Northern Barbados accretionary prisms, we measured the area, the decollement depth, the angle a of the upper envelope and the angle [beta] of the dip of the regional monocline. The continental sections of the Apennines accretionary prism have a deeper decollement than the oceanic sections of the Northern Barbados, 6-10 km depth and