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11 pages, 7 figures, supplementary material https://doi.org/10.1016/j.epsl.2020.116480, The formation of Cenozoic mountain belts in the Mediterranean realm was preceded by tens of millions of years of subduction, forming volcanic arcs, and frontal contractional systems. In addition, subduction usually involves slab rollback and formation of oceanic backarcs. Although such structure must have influenced the orogeny of Mediterranean mountain belts, no active analog has been mapped with modern crustal-scale seismic methods. Here, we study the entire Calabrian subduction system to map the structure resulting from Tethys lithosphere subduction and slab rollback, in a process that must be akin to that operating during a phase of the formation of the Mediterranean orogenic belts. We present a crustal-scale cross section of the entire Calabrian subduction system obtained from on- and off-shore wide-angle seismic data. The 2D P-wave velocity section shows spatially abrupt (, The CHIANTI survey was part of the HADES project funded by the Spanish MINECO (Ref # CTM2011-30400-C01 and CTM2011-30400-C02). [...] M. Prada is funded by the Beatriu de Pinós postdoctoral programme of the Government of Catalonia's Secretariat for Universities and Research of the Ministry of Economy and Knowledge (Ref # 2017BP00170), With the funding support of the ‘Severo Ochoa Centre of Excellence’ accreditation (CEX2019-000928-S), of the Spanish Research Agency (AEI)

19 pages, 18 figures, 1 table, The Gulf of Cadiz, off SW Iberia and the NW Moroccan margin, straddles the cryptic plate boundary between Africa and Eurasia, a region where the orogenic Alpine compressive deformation in the continental collision zone passes laterally to the west to strike-slip deformation. A set of new multibeam bathymetry, multi-channel and single channel seismic data presented here image the main morphological features of tectonic origin of a significant part of the Gulf of Cadiz from the continental shelf to the abyssal plain. These morphotectonic features are shown to result from the reactivation of deeply rooted faults that changed their kinematics from the early Mesozoic rifting, through the Late Cretaceous-Paleogene collision, to Pliocene-Quaternary thrusting and wrenching. The old faults control deep incised, more than 100 km long canyons and valleys. Several effects of neotectonics on deep water seabed are shown. These include: i) the complex morphology caused by wrenching on the 230 km long WNW-ESE faults that produced en echelon folds on the sediments; ii) the formation of up to 5 km wide crescent shaped scours at roughly 4 km water depth by reactivation of thrusts; iii) 10 km long creep folds on the continental slope; and iv) the formation of landslides on active fault escarpments. The present day deformation is partitioned on NE-SW thrusts and WNW-ESE to W-E strike-slip faults and is propagating northwards on N-S trending thrusts along the West Iberia Margin from 35.5°N to 38°N, which should be considered for seismic hazard, The work was sponsored by MATESPRO (PDCTM/P/MAR/15264/1999), EUROMARGINS SWIM (01-LEC-EMA09F), MVSEIS (01-LEC_EMA24F; PDCTM 72003/DIV/40018) and TOPOMED (TOPOEUROPE/0001/2007) projects. Instituto Scienze Marine (CNR) Bologna contribution 1587. JD and VV benefited from PhD grants from Fundação para a Ciência e a Tecnologia (SFRH/BD/31188/2006, SFRH/BD/17603/2004). We acknowledge the PARSIFAL Project MAR1998-1837-CE for the use of bathymetry data. We acknowledge the financial support from the ESF EuroMargins Program, contract n. 01-LEC-EMA09F and from EU Specific Programme "Integrating and Strengthening the European Research Area", Sub-Priority 1.1.6.3, "Global Change and Ecosystems", contract n. 037110 (NEAREST)