@article {Sallares2013,
	title = {{Seismic evidence of exhumed mantle rock basement at the Gorringe Bank and the adjacent Horseshoe and Tagus abyssal plains (SW Iberia)}},
	journal = {Earth and Planetary Science Letters},
	volume = {365},
	year = {2013},
	month = {mar},
	pages = {120{\textendash}131},
	abstract = {The Gorringe Bank is a gigantic seamount that separates the Horseshoe and Tagus abyssal plains offshore SW Iberia, in a zone that hosts the convergent boundary between the Africa and Eurasia plates. Although the region has been the focus of numerous investigations since the early 1970s, the lack of appropriate geophysical data makes the nature of the basement, and thus the origin of the structures, still debated. In this work, we present combined P-wave seismic velocity and gravity models along a transect that crosses the Gorringe Bank from the Tagus to the Horseshoe abyssal plains. The P-wave velocity structure of the basement is similar in the Tagus and Horseshoe plains. It shows a 2.5-3.0. km-thick top layer with a velocity gradient twice stronger than oceanic Layer 2 and an abrupt change to an underlying layer with a five-fold weaker gradient. Velocity and density is lower beneath the Gorringe Bank probably due to enhanced fracturing, that have led to rock disaggregation in the sediment-starved northern flank. In contrast to previous velocity models of this region, there is no evidence of a sharp crust-mantle boundary in any of the record sections. The modelling results indicate that the sediment overlays directly serpentinite rock, exhumed from the mantle with a degree of serpentinization decreasing from a maximum of 70-80\% under the top of Gorringe Bank to less than 5\% at a depth of \~{}20. km. We propose that the three domains were originally part of a single serpentine rock band, of nature and possibly origin similar to the Iberia Abyssal Plain ocean-continent transition, which was probably generated during the earliest phase of the North Atlantic opening that followed continental crust breakup (Early Cretaceous). During the Miocene, the NW-SE trending Eurasia-Africa convergence resulted in thrusting of the southeastern segment of the exhumed serpentinite band over the northwestern one, forming the Gorringe Bank. The local deformation associated to plate convergence and uplift could have promoted pervasive rock fracturing of the overriding plate, leading eventually to rock disaggregation in the northern flank of the GB, which could be now a potential source of rock avalanches and tsunamis. {\textcopyright} 2013 Elsevier B.V.},
	keywords = {Gravity modelling, Mantle exhumation, North Atlantic margin, Travel-time tomography, wide-angle seismics},
	issn = {0012821X},
	doi = {10.1016/j.epsl.2013.01.021},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-84874491076\&partnerID=tZOtx3y1},
	author = {Sallares, Valenti and Mart{\'\i}nez-Loriente, Sara and Prada, Manel and Gr{\'a}cia, Eul{\`a}lia and Ranero, C{\'e}sar and Gutscher, Marc-Andr{\'e} and Bartolom{\'e}, Rafael and Gailler, Audrey and Da{\~n}obeitia, Juan Jos{\'e} and Zitellini, Nevio}
}
@article {Sallares2011,
	title = {{Seismic evidence for the presence of Jurassic oceanic crust in the central Gulf of Cadiz (SW Iberian margin)}},
	journal = {Earth and Planetary Science Letters},
	volume = {311},
	number = {1-2},
	year = {2011},
	month = {nov},
	pages = {112{\textendash}123},
	abstract = {We investigate the crustal structure of the SW Iberian margin along a 340. km-long refraction and wide-angle reflection seismic profile crossing from the central Gulf of Cadiz to the Variscan continental margin in the Algarve, Southern Portugal. The seismic velocity and crustal geometry model obtained by joint refraction and reflection travel-time inversion reveal three distinct crustal domains: the 28-30. km-thick Variscan crust in the north, a 60. km-wide transition zone offshore, where the crust abruptly thins \~{}. 20. km, and finally a \~{}. 7. km-thick and \~{}. 150. km-wide crustal section that appears to be oceanic in nature. The oceanic crust is overlain by a 1-3. km-thick section of Mesozoic to Eocene sediments, with an additional 3-4. km of low-velocity, unconsolidated sediments on top belonging to the Miocene age, Gulf of Cadiz imbricated wedge. The sharp transition between continental and oceanic crust is best explained by an initial rifting setting as a transform margin during the Early Jurassic that followed the continental break-up in the Central Atlantic. The narrow oceanic basin would have formed during an oblique rifting and seafloor spreading episode between Iberia and Africa that started shortly thereafter (Bajocian) and lasted up to the initiation of oceanic spreading in the North Atlantic at the Tithonian (late Jurassic-earliest Cretaceous). The velocity model displays four wide, prominent, south-dipping low-velocity anomalies, which seem to be related with the presence of crustal-scale faults previously identified in the area, some of which could well be extensional faults generated during this rifting episode. We propose that this oceanic plate segment is the last remnant of an oceanic corridor that once connected the Alpine-Tethys with the Atlantic ocean, so it is, in turn, one of the oldest oceanic crustal fragments currently preserved on Earth. The presence of oceanic crust in the central Gulf of Cadiz is consistent with geodynamic models suggesting the existence of a narrow, westward retreating oceanic slab beneath the Gibraltar arc-Alboran basin system. {\textcopyright} 2011 Elsevier B.V.},
	keywords = {Geodynamic evolution, Jurassic oceanic crust, Refraction and reflection travel-time tomography, SW Iberian margin, Uncertainty analysis, wide-angle seismics},
	issn = {0012821X},
	doi = {10.1016/j.epsl.2011.09.003},
	url = {http://www.scopus.com/inward/record.url?eid=2-s2.0-81155155560\&partnerID=tZOtx3y1},
	author = {Sallares, Valenti and Gailler, Audrey and Gutscher, Marc-Andr{\'e} and Graindorge, David and Bartolom{\'e}, Rafael and Gr{\'a}cia, Eul{\`a}lia and D{\'\i}az, Jordi and Da{\~n}obeitia, Juan Jos{\'e} and Zitellini, Nevio}
}
