The Alboran Sea is one of the seas most widely studied by Spanish marine geologists. There are two main reasons: its structural framework and its oceanographic circulation. The Alboran Sea is interesting from a structural point of view because it is the site of collision between the Eurasian and African plates, and the basin is located within the framework of an orogenic process forming the surrounding Betic and Rif mountain belts. The westward displacement of the Alboran Domain (formerly the Alboran Microplate, Andrieux et al. 1971) between the two major plates has determined the development of the Arc of Gibraltar, within which the arc-shaped, semi-enclosed basin of the Alboran Sea is formed. The mentioned tectonic collision favours the development and activity of faults with associated crustal earthquakes. It has also contributed to the modelling of a highly irregular seafloor relief that reflects the complexity of the tectonic processes (Galindo-Zaldívar et al. 2018; Estrada et al. 2018). From an oceanographic point of view, the Alboran Sea is interesting because it is where the Mediterranean Waters (MWs) escaping toward the Atlantic Ocean encounter the Atlantic Water (AW) entering the Mediterranean Sea (e.g. Parrilla et al. 1986). This meeting of water masses produces a complex oceanography where the bottom layers of the Atlantic and Mediterranean water masses interact with the complex and irregular seafloor, conditioning the transport, sedimentation, and reworking of the near surface sediments, and forming sedimentary reliefs that increase the topographic complexity of the seafloor (Ercilla et al. 2016).

This work was supported by the following Spanish projects: INCRISIS, DAMAGE (CGL2016-80687-R AEI/FEDER), FAUCES (CTM2015-65461-C2-1-R) and ALSSOMAR S2S (CTM2017-88237-P), RNM 148 and RNM 328—Junta de Andalucía, MONCARAL and RIGEL projects (Instituto Español de Oceanografía) and Marlboro cruises. Likewise, this study was supported by the French program Actions Marges and the EUROFLEETS program-SARAS cruise (FP7/2007-2013; 228344). The Secretaria General de Pesca (Spain) yielded the bathymetric data from the northern part of the Alboran Sea. IHS-Kingdom Suite educational license.