Five major geological domains form the Gibraltar Arc System (GAS). The GAS is fronted in the Gulf of Cadiz by a large imbricated wedge of tectonically piled rock slices. A extended terrain forms the backstop of the wedge. The structural Gibraltar arc is formed by thrust and fold belt that overlays the edge of the extended terrain. To the east there are several extensional basins, in the Mediterranean portion of the system. The West Alboran Basin has subsided by almost 10 km but the sediment infill appears largely unrelated to normal faulting. The East Alboran Basin seafloor contains ridges and promontories that, where dredged and drilled, contain abundant volcanic rocks. Further east the South Balearic – North Algerian Basin is believed to be characterized by backarc oceanic basin. However, the different tectonic elements of the GAS have regionally poorly characterized basement, and their age, evolution and geodynamic origin are highly debated. Part of this uncertainty arises from the scarcity of deep-penetration modern geophysical data in most of the system. The goal of this contribution is to present a summary of results recently produced from models and images from the data collected in 4 recent marine experiments. We present P-wave velocity models across key areas of the system and new reflection images of the tectonic and sediment structures of the crust. Further we present magnetotellutic 3D models of the lithospheric structure. These results are use to interpret the Miocene formation of the GAS and Plio-Pleistocene continent collision that might explain the crustal-lithospheric structure. We conclude that a geodynamic process that is no longer active formed the geological domains of the GAS, and that a new deformation regime -active since about the Pliocene times- is controlling the currently active deformation

16TH SEISMIX International Symposium on Multi-scale Seismic Imaging of the Earth's crust and Upper Mantle, 12-17 October 2014, Castelldefels, Barcelona.-- 1 page

Peer Reviewed