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34th International Association of Sedimentologists (IAS) Meeting of Sedimentology, Sedimentology to face societal challenges on risk, resources and record of the past, 10-13 September 2019, Rome

IX Simpósio sobre a Margem Ibérica Atlântica (MIA 2018) - IX Simposio sobre el Margen Ibérico Atlántico - IX Symposium on the Iberian Atlantic Margin, 4-7 September de 2018, Coimbra.-- 2 pages, 1 figure, High-resolution multibeam bathymetry, seismic reflection data and underwater imagery were used to characterize the morphostructure as well as the ancient and contemporary habitat-forming species in three fields of clustered mounds that were recently discovered in the northern Alboran Sea. A total of 150 small mounds were detected between 140 to 300 m water depth. They display reliefs ranging from 2 to 17 m and circular or mainly NW-SE elongated shapes. The seismic reflection data highlight the presence of stacked buried and exposed mounds that exhibit acoustically transparent facies. They have an heterogeneous composition, mainly consisting of bioclasts of solitary scleractinians, bivalves and rhodoliths that are covered with soft sediments. These mounds may have gone through a complex mound development with a further geological and biological evolution in interaction with bottom currents. The analysis of these carbonate mounds may shed new light on the enormous scale of carbonate deposition along the Iberian Mediterranean margin, This work is a contribution to MONCARAL, funded by the Instituto Español de Oceanografia and FAUCES (CMT2015-65461-C2-R/MINECO/FEDER) projects

V Trobada de Tècnics de Col·leccions de Ciències Naturals de Catalunya celebrada el 25 de octubre de 2017 en el Institut de Ciències del Mar (ICM-CSIC) de Barcelona, Las colecciones de geología marina en el Instituto de Ciencias del Mar (ICM) albergan el mayor número de perfiles de sísmica y de muestras de sedimento del fondo y del subfondo marino, del CSIC. Miles de kilómetros en perfiles de sísmica y cientos de muestras de estos sedimentos han sido recuperados y coleccionados en el ICM para la exploración del fondo marino. Ambas colecciones presentan una fuente de datos en bruto de enorme valor científico y beneficio aplicado

IX Reunião do Quaternário Ibérico, Mudanças em sistemas ambientais e sua expressão temporal : IX Reunión del Cuaternario Ibérico, Cambios en sistemas ambientales y sus escalas temporales, Grupo de Trabalho Português para o Estudo do Quaternário (GTPEQ) - Asociación Española para el Estudio del Cuaternario (AEQUA),19-23 October 2017, Faro, Portugal.-- 2 pages, [EN] Multibeam bathymetry and high-resolution seismic data obtained during the RIGEL1116 oceanographic survey, have allowed to study the morphology of the Algeciras submarine canyon (NE Strait of Gibraltar). Three sectors (headwall, middle and distal) have been defined by dominant processes responsible for their formation and evolution. In the headwall sector, the general presence of scars around the canyon head and along its steep wall are cover in the seafloor by sediments reworked and redistributed by contouritic processes. Erosive processes are dominant in the middle sector especially in the incisive gullies (eastern flank) and crescent-shaped bedforms along the distal sector (thalweg and E wall) indicating sediment reworking caused probably by the interaction of the Mediterranean water mass, [PO] A batimetria multifeixe e os dados de sísmica com alta resolução adquiridos na expedição oceanográfica RIGEL1116, permitem o estudo da morfologia submarina do Canhãode Algeciras (NE do Estreito de Gibraltar). Foram definidos trêssetores (proximal, médioe distal) com base nos processos dominantes dasua formação e evolução. Há umapresença geralde cicatrizes erosivas em volta da cabeceira e ao longo da paredelateral do canhão, mas os processos coutouriticos retrabalham e redistribuem os sedimentos nesta área. Os processos erosivos são dominantes no setor mediano, especialmente nas ravinas incisivas (flanco leste) enquanto queformas crescentes de acamadamento ao longo do setor distal (talvegue e E muro) indicam retrabalhamento dos sedimentos, provavelmente causado pela interação da Massa de Água Mediterrânea

Bartolomé, Rafael ... et al.-- 7th International Workshop on Marine Technology – Martech Workshop 2016, 26-28 October 2016, Barcelona.-- 2 pages, 1 figure, In February and March 2014, Spanish, Mexican and British scientists and technicians explored the western margin of Mexico, a region with a high occurrence of large earthquakes (> Mw = 7.5) and tsunami generation, on board the British Royal Research Ship James Cook. This successful joint cruise, named TSUJAL, was made possible thanks to a cooperative agreement between NERC and CSIC as part of the Ocean Facilities Exchange Group (OFEG), a major forum of European oceanographic institutions for the exchange of ship time, equipment and personnel. A dense geophysical data set was acquired using for the first time 6 km length seismic streamer facilities from Spain’s Consejo Superior de Investigaciones Cientificas (CSIC), usually operating in the Spanish RV Sarmiento de Gamboa, onboard the British RRS James Cook by solving all mechanical, electrical and electronic problems. The RRS James Cook in turn provides the seismic source and the acoustic, hullmounted echosounder operated by the British Natural Environment Research Council (NERC). Multiscale seismic and echosounder images unravel the subduction geometry, nature of the crust, and evidence faults and mass wasting processes. The data are crucial to estimating fault seismic parameters, and these parameters are critical to carrying out seismic hazard in Mexico, especially when considering largemagnitude earthquakes (Mw 8.0), and to constrain tsunami models

Juan, Carmen ... et al.-- 5th International Geologica Belgica Meeting, 26-29 January 2016, Mons, Belgium

Ercilla, Gemma ... et. al.-- Regional Committee on Mediterranean Neogene Stratigraphy (RCMNS) Interim Colloquium 2015 - Mediterranean-Atlantic Gateways (Neogene to present), 5-8 May 2015, Rabat, Marocco.-- 1 page, The spatial and temporal evolution of contouritic features as well as changes in their morphology and type suggest: i) their formation roughly agrees with the present-day Mediterranean water masses distribution, i.e., the Low Dense Mediterranean Water-LMW (Winter Intermediate Water + Levantine Intermediate Water) in the Spanish margin, and the High Dense Mediterranean Water ¿DMW( Deep Mediterranean Water) in the subbsains and Moroccan margin; ii) the important role played by the changing landscape during the Pliocene and Quaternary, with important consequences for the water masses circulation, especially for the DMW. Point and linear barriers, and troughs and elongated subbasins, condition a complex current distribution, especially for the Quaternary; iii) a higher energetic recirculation of the DMW in the Western Alboran Basin; iv) a more an enhanced density contrast between the LMW and DMW during the Quaternary; and v) larger vertical and horizontal displacements of the water mass interfaces during the Quaternary related to 4th-order glacioeustatic change. These frist paleoceanographic reconstructions have implication for the ventilation of Mediterranean waters trough the Strait of Gibraltar, Mediterranean Outflow Water formation, Altantic-Mediterranean interchange and then for the AMOC and climatic changes in the past.

Vázquez, J. T. ... et al.-- Submarine Canyon Dynamics in the Mediterranean and Tributary Seas - An integrated geological, oceanographic and biological perspective, 15-18 April 2015, Sorrento, Italy.-- 14 pages, 5 figures.-- This is a contribution of the Continental Margins Research Group (CMRG- 2009SGR1071, Generalitat de Catalunya), Geosciences Marine Research Group (GEMAR - lEO) and Littoral and Marine Geophysical and Geological Research Group (RNM 0328, PAIDI), The analysis of a data set of multibeam bathymetry plus high resolution seismic and parametric profiles allow us to characterize the geomorphologic units on the Alboran Sea-floor as well as the evolution of morpho-sedimentary systems along the Pliocene and Quaternary, later than the main erosive Messinian event. Since the opening of the Gibraltar Straits, the sedimentary evolution of this basin has been controlled by the interchange of water masses between the Atlantic Ocean and the Mediterranean Sea. Basin physiography is also a consequence of the Pliocene-Quaternary compression which has progressively uplifted the sourrounding reliefs and deforms the interior and the margins of the basin. On this scenario, several submarine canyons and gullies have been developed in this basin which traverse especially the northern margin and the flanks of the Northern Alboran Ridge, without affecting the African margins. This fact must be related to the action of bottom contour currents which constitute the main morpho-sedimentary process. The influence of water masses distributed the sedimentary input carried by rivers and coming from the erosion of surrounding ranges. In the southern margin of this basin this influence is stronger and inhibits the development of transversal submarine canyons, Funding for this research was provided by the following projects: CONTOURIBER, MONTERA, TOPOMED, MOWER, and VIA TAR

Roque, C. ... et. al.-- VIII Simposio sobre el Margen Ibérico Atlántico (MIA15), del 21 al 23 de septiembre de 2015, Málaga.-- 3 pages, 3 figures, The Sines Contourite Drift, located in the West Portuguese Margin, is affect by slope failure and mass movements. Evidences of the occurrence of such processes are seen in seismic reflection seismic and multibeam bathymetry acquired in this margin during several cruises. An extensive area of the Sines Drift, about approximately 52 km long and 34 km wide, affected by failure and mass movements was discovered during the MOWER cruise in September-October of 2014. The Sines Drift is a plastered drift developed in the footwall of the Pereira de Sousa Fault, a normal inactive fault inherited from the Mesozoic rifting phases. The gravity-driven deposits resulting from its failure (e.g slumps, debris flows) accumulated in the Lebre Basin. Seeing the seismotectonic framework of the WPM earthquake triggering could be considered, but the geotechnical nature and specific physical/sedimentological properties of the contourite deposit need to be taken in account, This work was supported by CONDRIBER (FCTPTDC/GEO-GEO/4430/2012) and MOWER (CTM2012-39599-C03-02) projects, and by IDL (IDL-FCTUID/GEO/50010/2013)

Bartolomé, Rafael ... et. al.-- Inciativa Ibérica para el Estudio de las Fallas Activas, Segunda Reunión Ibérica sobre Fallas Activas y PaleosismologíaI IBERFAULT 2014, 22-24 de octubre de 2014, Lorca, España.-- 4 pages, 3 figures, 1 table, During the spring of 2014, scientists onboard the RSS James Cook explored the western margin of Mexico through a dense geophysical sampling of the plates. Data obtained during the oceanographic survey images the crustal transition from an active margin where the Rivera Plate subducts beneath the North American plate, a process that has been taking place since Middle Miocene (10 Ma), to the rifting zone in the Gulf of California. The tectonic processes occur in a geological setting of high seismicity, where earthquakes M= 8.2 have taken place and where a high probability of tsunami generation exists. From a tectonic point of view, this is a complex region where several plates interact with accretionary processes in the East Pacific Rise, subduction processes occurs in the Middle American Trench and an important segmentation of extensional faults exists in the mouth of the Gulf of California. The new TSUJAL seismic images and models recently obtained unravel the geometry and morphology of faults and mass wasting, possible sources of seismic and tsunami events, as well as the crustal structure in the different domains of the Mexican margin, This research was supported by TSUJAL (Crustal characterization of the RiveraPlate-Jalisco Block boundary and its implications for seismic and tsunami hazard assessment, CGL2011-29474-C02-01) and FOMIX (Fondo Mixto CONACYT-Gobierno del Estado de Jalisco) projects. [...] R. Bartolome acknowledges financial support through the Ramon y Cajal program

2nd Deep-Water Circulation Congress: The Contourite Log-book, 10-12 September 2014, Ghent, Belgium.-- Juan, Carmen ... et. al.-- 2 pages, 2 figures, A multiple Contourite Depositional System has been defined in the Plio-Quaternary sedimentary register in the Alboran Sea. This multiple system formed by the Atlantic and the low density and high density Mediterranean Waters, which shaped the margins and basins since the opening of the Gibraltar Strait. Three different (paleo)circulation scenarios are proposed since then: the Atlantic water Flooding;the Pliocene circulation, characterized by immature low and high density Mediterranean waters and a strong countercurrent in the Western Basin; and the Quaternary circulation, characterized by tabular Mediterranean water masses with multiple current dynamics,an increasing influence of density contrasts, and climate shifts causing major vertical and horizontal displacements of their interfaces, CTM 2008-06399-C04; CTM2009-14157-C02-02; CTM 2012-39599-C03-02; IGCP 619; INQUA 1204; Actions Marges; EUROFLEETS FP7/07-13, n228344

2nd Deep-Water Circulation Congress: The Contourite Log-book, 10-12 September 2014, Ghent, Belgium.-- Ercilla, Gemma ... et. al.-- 2 pages, 1 figure, Multidisciplinary work between oceanography, geomorphology and sedimentology has uncovered evidence explaining the uneven development of the turbidite systems (TSs) in the Alboran Sea. Nine TSs have been mapped in the Spanish margin, ranging from sandy to mixed sand-mud fans, and which become sandier towards the Strait of Gibraltar; in contrast TSs do not develop in the Moroccan margin, where three canyons incise the continental slope but there is no TS formation. We interpret that the uneven development of TSs in the two margins and their variable architectures are conditioned by the interaction of alongslope with downslope processes. Two different interaction scenarios with varying intensities are proposed, This work is in the framework of the MOWER (CTM2012-39599-C03-02), MONTERA (CTM2009-14157-C02-02), projects and Action Marges Program

Juan, Carmen ... et. al.-- Symposium on Integrating New Advances in Mediterranean Oceanography and Marine Biology, 26-29 November 2013, Institut de Ciències del Mar (CSIC), Barcelona, Catalunya, Spain, CONTOURIBER Team, MONTERA Team, ACTIONS MARGES team, The cross-disciplinary fields including geomorphology, sedimentology and physical oceanography have highlighted the governance of the water masses on the sedimentation of the margins and basins of the Alboran Sea during the Pliocene and Quaternary. The results obtained from analyzing the intricate relationship between the sedimentary processes and the action of the light and dense Mediterranean waters (MW) has been transferred to the paleosurfaces of the main stratigraphic divisions. This has allowed us to define multiple Contourite Depositional Systems, dominated by a great variety of depositional and erosive features. Their seismic facies as well as their temporal and spatial variability suggest the action of low dense and high dense MW since the beginning of the Pliocene, and have allowed decoding the paleocirculation, that involves significant relocation of main flow pathways, both longitudinal and transversal. We have inferred three circulation models: 1) during the infilling of the Mediterranean basin, highly erosive; 2) during the Pliocene a strong countercurrent eroded the Spanish base of slope, comprising two stages: 2a) Lower Pliocene, the Western and Southern basins were connected allowing the circulation of high dense waters; 2b) Upper Pliocene, the uplift of the SW section of the Alboran Ridge interrupts the connection; and 3) the Quaternary model is similar to the present day, characterized by an enhanced density contrast between the low and high dense MW and a less energetic recirculation. These stages reflect variability in the bottom-current regimes and related along-slope efficiency in transport, deposition and erosion, CTM 2008-06399-C04/MAR, CTM 2012-39599-C03, IGCP 619, INQUA 1204, Actions Marges, EUROFLEETS - FP7/2007-2013 n° 228344

Ercilla, Gemma ... et al.-- 30th IAS Meeting of Sedimentology, 2-5 September 2013, Manchester, The Alboran Sea is a river and eolian influenced margin characterized by recent depositional and erosive contourite features over the continental margins and deep basins. Their formation has been governed by the action of four superimposed water masses. The surficial one is the Atlantic Water (AW) and the other underlying three are of Mediterranean origin; from top to bottom they comprise the Winter Intermediate Water (WIW), Levantine Intermediate Water (LIW), and Western Mediterranean Deep Water (WMDW). The combined geomorphologic, seismic and oceanographic observations allowed to suggest that the most common processes responsible of the formation of contourites are attributed to: 1) turbulence (e.g., internal waves) along the water mass interphases, mostly those with the most enhanced contrast density (AW and WIW+LIW; LIW+WMDW) as well as their vertical displacement with time; 2) the occurrence of solitons related both to the AW circulation along the shelf-break and the Mediterranean waters interaction with morphological highs; 3) local helicoidal cores when LIW and WMDW meet with numerous highs; 4) topographic steering of the WMDW; 5) cyclonic recirculation on the WMDW: and 6) piracy of fine sediment transported within the gravity flows. When river and eolian sediments arrive to the sea they are quickly and largely dispersed first by the AW and later down by Mediterranean waters. Sediment dispersal is favored by the nepheloid layers formation along the water-masses interphases. These layers are also fed by resuspension of sediment when internal waves and solitons interact with the seafloor and local bottom current enhances, and by sequestration of fine sediment from gravity flows. The fast settling of the suspended particles would occur when current velocities decrease. Thus, nepheloid layers represent probably the major way of sediment transport at different water depths and depositing basinward with predominant along-slope component, This study is supported by the projects CTM 2008-06399-C04/MAR, CTM 2012-39599-C03, IGCP 619, INQUA 1204, ACTIONS MARGES program and EUROFLEETS Programme (FP7/2007-2013) under grant agreement n° [228344]

Ercilla, Gemma ... et. al.-- AAPG European Regional Conference & Exhibition. Exploring The Mediterranean: New Concepts In An Ancient Seaway, 8-10 April 2013, Barcelona, Spain

Juan, Carmen ... et al.-- Dialogue Between Contourite and Oceanography processes International Workshop, University of Hull, 28-26 January 2013, University of Hull, UK, This work provides new insights on the Pliocene & Quaternary seismic stratigraphy in the Alboran Sea from the analyses of single- and multi-channel seismic profiles. Although previous seismic stratigraphic studies were carried out, mostly in the Spanish margin, the addition of new boundaries (Lower Pliocene Revolution -LPR-, Base of Quaternary Discontinuity -BQD- and Middle Pleistocene Revolution -MPR-) to the previous ones (Messinian Erosive surface -M-, Top Lower Pliocene -P1-, Top Gelasian -P2-, Top Lower Quaternary -Q1-) and the accurate cartography of the different sedimentary systems for each stratigraphic division in both, the Spanish and Moroccan margins, as well as adjacent basins, provide a new stratigraphic architecture and new evolutive models for Pliocene & Quaternary times. The stratigraphic architecture of the Alboran Basin below the shelf break, is mostly made of the stacking of contourite deposits and locally of turbidite fans and mass-transport deposits, all separated by erosive boundaries, that led to the outbuilding of the margins and infilling of the basins. Contourites have resulted from the activity of the Mediterranean Waters outflowing toward the Gibraltar Strait and the collateral influence of the incoming surficial Atlantic Water. The spatial and temporal evolution of contourites as well as changes in their morphology and type suggest at least two major building stages during the Pliocene and another two during the Quaternary; they also invoke the action of less dense and high dense Mediterranean waters since the beginning of the Pliocene, just after the Zanclean flooding. These evolutionary stages reflect variability in the bottom-current regimes and related along-slope efficiency in transport, deposition and erosion. This variability has been controlled by major changes in climate and related sea-level changes, local topography related to tectonic regime and sediment availability. On the other hand, the paleoceanographic reconstruction has allowed inferring the ancient pathway of the Mediterranean water masses and suggest two circulation models: the first corresponding to the Quaternary, being similar to the present day, and the second one corresponding to the Pliocene, when a stronger countercurrent eroded the Spanish base of slope. This contribution represents both a good example of decoding contourite processes related to the action of ancient water masses circulation based on the sedimentary record and the interplay between down- and along-slope processes

Ercilla, Gemma ... et al.-- Dialogue Between Contourite and Oceanography processes International Workshop, 28-26 January 2013, University of Hull, UK, We show how the dialogue between sedimentology, geomorphology and descriptive oceanography end in a fundamental change in sedimentological thinking by presenting a case of study in the Alboran Sea. The integration of results obtained from the reinterpretation of seismic and acoustic records and analyses of CTD (Conductivity, Temperature and Depth) data has allowed to demonstrate that along-slope are the dominant processes, contrary to established thinking up to now, which considered that turbidity and mass-transport processes were the prevailing processes. Contourites features, evolving under the action of several water masses, are the main morphosedimentary features that characterize the margin and basin seafloor from the shelf-break (> 90 m water depth). Several types of contourite features have been characterized, depositional (plastered, sheeted, elongated-separated, & confined); erosive (moats, channels & furrows) and mixed (contourite terraces). These features are interrupted locally by the construction of turbiditic fans, mainly in the Spanish margin, and by sedimentary instabilities that affect locally to the slope and seamounts. This new morphosedimentary sediment view of the Alboran Sea reveals for the first time the important role of sedimentary processes (transport, sedimentation and erosion) associated with five major water masses, one of Atlantic origin (Atlantic Water -AW-), three of Mediterranean origin (Winter Intermediate Water -WIW-, Levantine Intermediate Water -LIW-, Western Mediterranean Deep Water -WMDW-), and a local mixed water that result from the blending of AW and WMDW. These currentdominated processes have three different domains of acting: 1) on the large-scale morphology of the physiographic provinces; 2) on the small-scale morphosedimentary features characterizing the physiographic provinces; and 3) on depositional model of the adjacent downslope sedimentary systems

Juan, Carmen ... et al.-- 30th IAS Meeting of Sedimentology, 2-5 September 2013, Manchester, In the Alboran Sea (SW Mediterranean) have been recently defined multiple Contourite Depositional Systems (CDSs) formed by a great variety of erosive and depositional elements developed during the Plio- Quaternary. Descriptive oceanography shows four superimposed water masses, one of Atlantic origin (Atlantic Water, AW) and three of Mediterranean origin (Winter Intermediate Water, WIW; Levantine Intermediate Water, LIW; Western Mediterranean Deep Water, WMDW). Stratigraphic horizons dividing the Plio-Quaternary sedimentary record are genetically related to glacioeustatic and tectonic unconformities. Tectonic pulses have influenced the Alboran margins and subbasins topography and environments generating sea-floor irregularities that affected to the water masses circulation. Detailed seismic analysis of the contourite features making up the stratigraphic divisions and their vertical and spatial distributions, suggest the development of the Alboran CDSs involved local relocation of the water masses pathways. The integration of these results with the distribution of the contourite features during different time intervals allows the decoding of the water-mass circulation in the Pliocene and Quaternary Seas of the Alboran Basin. CDSs onset was initiated after the event of the Atlantic inflow (Zanclean flooding) in the Messinian. This event produced a regional unconformity characterized by erosive features. Sedimentation after the flooding was mainly along the distal margins and basins influenced by Mediterranean Waters (MW), mostly infilling the western basin with sheeted drifts and with less important deposition in the margins. The Pliocene Sea was characterized by the presence of an enhanced density contrast boundary between the AW and MW, as suggested by the formation of a narrow contourite terrace in the upper continental slopes, whereas the definition of the early light (WIW+LIW) and dense (WMDW) waters seemed to be more subdued. The early dense water recirculated in the western basin forming a countercurrent which contributed to form a striking erosive escarpment, and developed local flow cores associated to topographic irregularities. During Quaternary, contourite sedimentation dominates in the margins, forming striking plastered drifts and developing contourite terraces at different water depths, along both the upper and lower Spanish continental slope and upper Moroccan slope. We suggest that since the Quaternary, the Alboran Sea has better developed interphases between the AW and MW and between the Light and Dense MW, whose effect is enhanced by the high frequency and amplitude sea level changes. This period is also characterized by a decrease in the activity and/or energy of the countercurrent of the dense water mass in the western basin, as well as the lesser development of local flow cores in the deep basins due to the obliteration of topographic irregularities. Therefore, an important change in contourite deposition is related to the based of the Quaternary when the contourite features enhance, CTM 2008-06399-C04/MAR, CTM 2012-39599-C03, IGCP 619, INQUA 1204, Actions Marges, EUROFLEETS - FP7/2007-2013 n° 228344.

Juan, Carmen ... et. al.-- 86° Congresso della Società Geologica Italiana, 18-20 Settembre 2012, Arcavacata di Rende

4 páginas, 4 figuras. -- VIII Congreso geológico de España, Oviedo., [EN] This paper presents the morpho-seismic characterization of Quaternary mass-movement in the Almeria margin and eastern Alboran Basin on the basis of the bathymetric and high and very high-resolution seismic data. The mass-movement deposits are located in two sedimentary environments, open slope and morphological highs. The area affected by these deposits varies between 10 km2 and 255 km2. A classification of these mass movements deposits, based on a series of criteria including the causative mechanism, the source area location and physiographic location, is here proposed, differentiating three types of systems: i) attached to platform, ii) attached to slope and iii) detached locally., [ES] Este trabajo presenta la caracterización morfo-sísmicas de depósitos de movimientos en masa que se desarrollaron durante el Cuaternario en el margen de Almería y en la Cuenca Oriental de Alborán en base a datos batimétricos y sísmicos de alta y muy alta resolución. Los depósitos de movimientos en masa están localizados en dos ambientes sedimentarios, talud abierto y altos morfológicos. Las áreas afectadas por estos depósitos varían entre 10 km2 y 255 km2. Asimismo, se propone una clasificación de los movimientos en masa para estos márgenes en base a una serie de criterios que incluyen el mecanismo causante, la localización del área fuente y la localización fisiográfica y que estaría constituida por tres tipos de sistemas de inestabilidad sedimentaria: i) adosados a plataforma, ii) adosados a talud, iii) localmente no adosados., La realización de este trabajo ha sido posible gracias a la ayuda económica proporcionada fundamentalmente por el Plan Nacional I+D+i a través de los proyectos MONTERA (CTM-14157-C02-02/MAR), CONTOURIBER (CTM2008-06399-C04-04/MAR) y SAGAS (CTM2005-08071-C03-02/MAR). Se agradece a la Secretaria General de Pesca los datos de batimetría multihaz.

Since the Tortonian, the thinned continental crust and the overlying sedimentary cover of the Alboran Sea are submitted to tectonic inversion due to the convergence between Eurasia and Africa. The past and present deformation is significant along the Moroccan margin where the MARLBORO-1 cruise in 2011, acquired 1100 km of mid-resolution seismic reflection along 20 profiles perpendicular and parallel to the margin, off Al Hoceima, to latitude 36°N. The study area located on the Xauen/Tofino banks and the South Alboran ridge off Morocco, shows signs of both past and present strong tectonic deformation, submarine landslides, and contourites, EGU General Assembly 2012, Vienna, 22-27 April

D'Acremont, E. ... et. al.-- European Geosciences Union General Assembly 22-27 April 2012, Vienna, Austria.-- 1 page, Since the Tortonian, the thinned continental crust and the overlying sedimentary cover of the Alboran Sea are submitted to tectonic inversion due to the convergence between Eurasia and Africa. The past and present deformation is significant along the Moroccan margin where the MARLBORO-1 cruise in 2011, acquired 1100 km of mid-resolution seismic reflection along 20 profiles perpendicular and parallel to the margin, off Al Hoceima, to latitude 36ºN. The study area located on the Xauen/Tofino banks and the South Alboran ridge off Morocco, shows signs of both past and present strong tectonic deformation, mass-movement deposits (mostly slides and mass flow deposits), and contourites. The lateral and longitudinal evolution of contourites and mass movement deposits and the geometric relationships between those deposits and active tectonic structures have been studied. In the distal margin, contourites and gravitational instabilities are the depositional systems that best record the tectonic signal of the area since at least the Messinian. On the two flanks of the Xauen/Tofino and South Alboran ridge, the sedimentary register affected by growth-faults is mainly composed of contourites. Internal strata pattern, spatial and temporal distribution of thickness and depocenters, and discontinuities help to infer sedimentary processes and their interaction with tectonics. In the southern Alboran Sea where the bathymetry shows abrupt slopes, the recurrent seismic activity seems to be the main factor triggering mass wasting as witnessed by the Mass transport complexes (MTCs). Recent MTCs originate from escarpments on the edge of the contourites. However, in most cases the seismic reflection data show the depositional bodies of numerous slides linked to the activity of growth-faults and thrusts observed on the Xauen and Tofino Bank’s north flanks. Tectonic inversion is recorded since the late Miocene with an acceleration of the uplift and compressional activity evidenced during Messinian. The Xauen/Tofino and Alboran highs have a strong internal complexity with tight folds, thrusts, unconformities, intruded magmatic and mud bodies showing different stages and styles of deformation. Offshore Al Hoceima, between the South Alboran Ridge and the adjacent Tofino Bank, a network of active normal faults and strike-slip faults have been imaged that change in direction close to the Morocco coast

Gemma Ercilla ...et al. -- 4 páginas, 2 figuras. -- VIII Congreso Geológico de España, Oviedo., [EN] This paper presents a new view of recent sedimentation in the Alboran Sea, based on the analysis of the largest database of available seismic profiles in that sea. The results reveal that contourites represent the main morphosedimentary features that characterize the margins and basins. Several types of contourite features have been characterized, both depositional (plastered, sheeted, elongated-separated, confined, and channel-related) and erosive (moats, terraces and furrows). These elements are interrupted by the construction of turbidite fans, mainly in the Spanish margin, and by sedimentary instabilities that locally affect to the open slope, Alboran Ridge and morphological highs. This new morphosedimentary view of the Alboran Sea reveals for the first time the important role of along slope processes (transport, sedimentation and erosion) associated with Mediterranean water masses., [ES] En este trabajo se presenta una nueva visión de la sedimentación reciente en el Mar de Alborán, en base al análisis de la mayor base de datos con perfiles sísmicos disponibles en dicho mar. Los resultados obtenidos revelan que las contornitas representan el principal elemento morfosedimentario que caracteriza a los márgenes y las cuencas. Se han caracterizado varios tipos de elementos contorníticos deposicionales (crestas adosadas, laminares, elongadas-separadas, confinadas y de canal) y erosivos (fosas, terrazas y surcos). Estos elementos están interrumpidos por la construcción de abanicos turbidíticos, principalmente en el margen español, y por inestabilidades sedimentarias que afectan localmente al talud abierto, a la Dorsal de Alborán y a los altos morfológicos. Esta nueva visión morfosedimentaria del Mar de Alborán pone de manifiesto por primera vez el importante papel de los procesos sedimentarios longitudinales al margen (transporte, sedimentación y erosión) relacionados con las masas de agua mediterránea., This work is in the framework of the CONTOURIBER (ref: CTM 2008-06399-C04-04/MAR), MONTERA (REF: CTM-14157-C02-02) projects and Action Marges Program, thanks to an important effort between national and international geologists working in the Alboran.

ISMS12 International Symposium in Marine Sciences - XVI SIQM Seminario Iberico de Quimica Marina, 24-26 de enero de 2012, Cádiz, A new and detailed Plio-Quaternary seismic stratigraphy has been defined in the Western Alboran Basin. The new stratigraphy has incorporated new three major discontinuities that reflect drastic changes in climate and paleoceanography. They are the followings: the LPR discontinuity (Lower Pliocene Revolution) of 4.2 Ma; the UPR/BQD discontinuity (Upper Pliocene Revolution, Base of Quaternary) of 2.4 Ma; and the MPR discontinuity (Middle Pleistocene Revolution) of 0.9 Ma. These new unconformities divide the Plio-Quaternary sedimentary register overlying the Messinian erosive surface (M discontinuity) into four new seismic divisions. The seismic facies analysis of these divisions have allowed defining a new depositional architecture for the Spanish and Moroccan margins and the adjacent western Alboran basin. This architecture is made up of two major types of sedimentary systems: contouritic and turbiditic. The spatial and temporal distributions of their deposits have allowed reconstructing the depositional history of the western Alboran Sea. This history involves significant relocation of main flow pathways, both longitudinal and transversal. The relocation of the longitudinal pathways seem to have been conditioned by the interplay/feedback between major changes in the oceanographic scenario of the Alboran Sea since the Atlantic flooding, with several morphological and sedimentary factors that have also been conditioned by tectonic activity

Ercilla, Gemma ... et. al.-- Parte seconda 86° Congresso della Società Geologica Italiana Note brevi e riassunti, Arcavacata di Rende, 18-20 Settembre 2012.-- 3 pages, Critical reviews of the available seismic records and analyses of CTD data in the Alboran Sea have changed the previous interpretations about the types of deposits making up the nearsurface sediments of the Alboran Sea. During the last 20 years many studies about sedimentation in the Alboran Sea suggested that turbiditic fans, gravitative deposits and hemipelagites characterized the slopes and sub-basins of the Alboran Sea. The new results suggest the dominance of contourites interrupted by submarine fans and sedimentary instabilities in those physiographic domains, This work has been developed thanks to the CONTOURIBER (REF. CTM2005-08071-C03-02/MAR) and MONTERA (REF. CTM-14157-C02-02/MAR) projects, and Action Marges Program

Carmen Juan ...et al. -- 4 páginas, 2 figuras, 1 tabla. -- VIII Congreso Geológico de España, Oviedo., [EN] Several attempts for establishing a good Plio-Quaternary stratigraphy were proposed and disputed since the beginning of the studies in the Alboran Sea during the 80’s. Now, we have reviewed all the available data with the purpose of improving the detail of the previous stratigraphy by adding new chronostratigraphic boundaries (Lower Pliocene Revolution –LPR-, Base Quaternary Discontinuity –BQD- and Middle Pleistocene Revolution –MPR-) with paleoclimatic and paleoceanographic significances. Their addition have allowed tracking the effects of the Mediterranean water masses on the sedimentation since the opening the Strait of Gibraltar. The new results indicate that the Pliocene and Quaternary sedimentary record is mainly characterized by contourites, comprising both depositional and erosive features, that contribute to the outbuilding of the margins and infilling of the basins. Thus, a new Plio-Quaternary sedimentary evolution model with dominance of the alongslope processes has been established for the Alboran Sea., [ES] Desde el inicio de la investigación científica en el Mar de Alborán en los años 80 se han presentado varios trabajos de estratigrafía Plio-Cuaternaria. Recientemente hemos revisado todos los datos disponibles con el propósito de mejorar el nivel de detalle de la estratigrafía previa, añadiendo nuevos límites cronoestratigráficos (Lower Pliocene Revolution –LPR-, Base Quaternary Discontinuity –BQD- y Middle Pleistocene Revolution –MPR-) con significados paleoclimático y paleoceanográfico. Su inclusión nos ha permitido rastrear los efectos de las masas de agua mediterráneas sobre la sedimentación desde la apertura del Estrecho de Gibraltar. Los nuevos resultados indican que el registro sedimentario Plio-Cuaternario está principalmente caracterizado por contornitas, que comprenden tanto rasgos deposicionales como erosivos, que contribuyen a la construcción de los márgenes y relleno de las cuencas. Esto ha permitido establecer un nuevo modelo de evolución sedimentaria durante el Plio-Cuaternario con dominancia de los procesos longitudinales para el Mar de Alborán., This work has been developed thanks to the CONTOURIBER (REF. CTM2005-08071-C03-02/MAR) and MONTERA (REF. CTM-14157-C02-02/MAR) projects, and Action Marges Program.

Alonso, B., Ercilla, G., Estrada, F., Casas, D., García, M., Vázquez, J.T., Farran, M.,(2010). New insights on the distal Almeria fan: late Quaternary architecture and evolution (SW Mediterranean Sea). 23eme Réunion des Sciences de la Terre, Bordeaux; p. 8-9. Burdeaux (Francia) 2010-10-25 / 2010-11-29, The present work is focused on the Distal Almeria Fan located on the Almeria margin and Eastern Alboran Basin. This fan is fed by the Andarax River, a relatively long submarine canyon (55 km) (Almeria Canyon) and several gullies that erode the slope deposits., Contouriber, Montera and SagasBis: spanish MICINN projects.

39th CIESM Congress, 10-14 May 2010, Venice, This work presents the Quaternary mass-movement deposits in the Almeria open slope and seamounts between 107 and 2000 m water depth. Massmovements related to the Almeria Fan are excluded. This area is located in the eastern Alboran Sea (SW Mediterranean) and represents a tectonically active area characterised by a complex morphostructure with margins, basins, and seamounts., Contribution to MONTERA, CONTOURIBER, and TOPOMED Projects financed by the Spanish MICINN

Nadal-Ferreras, Manel ...et al.-- 217 pages, 66 figures, En les últimes dècades l’ús creixent del litoral ha influït en el balanç de sediments de la costa i ha afectat l'estabilitat de les platges. A la costa del Maresme, l'alt potencial de transport de sediments al llarg del litoral i la urbanització creixent han accentuat el retrocés de les platges. La construcció de ports i d’altres estructures costaneres, que actuen com a barreres per al transport longitudinal de sediments, intensifica l'erosió d'algunes zones, que deixen de rebre aportacions de sediments. Alhora, l'acumulació dels sediments erosionats als ports pot arribar a afectar-ne la funcionalitat. [...]

El objeto del presente trabajo es el estudio de los colapsos gigantes presentes en la región del Banco de Galicia a partir de la estructura de la que se tiene una documentación más completa: el colapso que hemos denominado “BURATO ERGAP”. Hasta el momento se han descrito colapsos de grandes dimensiones en otras zonas del Margen Ibérico Atlántico como en el Golfo de Cádiz 6º Simposio sobre el Margen Ibérico Atlántico (MIA09), 1-5 de diciembre 2009, Oviedo Multibeam and seismic data acquired during the ERGAP 1 and ERGAP 2 allowed the recognition and study of three big depressions which are located in the continental slope southeast of the Galicia Bank. These depressions correspond to collapses circular in shape that reach 370 m depth and whose size range between 2000 y 5000 m. Among them the so called BURATO ERGAP have been analysed in detail. Seismic records from this depression indicate its erosive character, the occurrence of a diapir underneath related to a shale layer, numerous faults that extend from the seafloor to the shale layer at both sides of the depression and finally and transparent seismic facies that could be associated to fluid venting. The genesis of this collapses must be explain in the framework of the Cenozoic Pyrenean compressive events, where faulting of the sedimentary cover over a viscous shale layer among other factors can be invoked to explain this outstanding features Este trabajo ha sido desarrollado mediante los proyectos de investigación ERGAP (VEM 2003-20093-CO3) y CONTOURIBER (CTM2008-06399-C04/MAR), contribuyendo una contribución al proyecto TOPOIBERIA (Consolider-Ingenio 2010, CSD2006-0041)

Extended abstracts International Conference on Seafloor Mapping for Geohazard Assessment, Fiorio d'Ischia, Italy, May 11-13, 2009

VII Congreso Geológico de España, 14-18 Julio 2008, Las Palmas de Gran Canaria

VII Congreso Geológico de España, 14-18 Julio 2008, Las Palmas de Gran Canaria.-- 4 pages, 4 figures, [EN] A monitoring of El Masnou has been performed during one year (June’06 to May’07) for the assessment of the sand trapped by the harbour towards a better management. It has been estimated a volume of sand accumulated at the harbour of 70,510 m3/ year. It shows similar characteristics than the sand of the adjacent beaches and it is accumulating close to the harbour at water depths shallower than 8-9 m. Attaining a better management of these deposits it has been proposed some guidelines: (i) an annual dredge of about 70,000 m3 of sand donwdrift to the harbour in order to recover the sediment transport and guarantee the free access to the harbour; (ii) dredges at a maximum water depth of 8-9 m for guarantee the extraction of the sand intercepted; (iii) the consideration of the sand trapped by harbours as strategic sediment reservoirs; and (iv) the collapsing of the current trench wall landwards along the seaport before next activities for retarding the sand that reaches the entrance of seaport and therefore ensure the access to the seaport, [ES] Se ha realizado un seguimiento de la zona de El Masnou durante un año (Junio’06 a Mayo’07), con el fin caracterizar la arena interceptada por el puerto para una mejora de la gestión de estos depósitos. Se ha estimado un volumen de arena acumulada de 70.510 m3/año que muestra características muy similares a la arena de las playas colindantes y se acumula en la zona próxima al puerto hasta una profundidad de agua de 8-9 m. Para una mejora en la gestión de estos depósitos, se han extraído una serie de recomendaciones: (i) el dragado anual de 70.500 m3 a través del puerto para la recuperación del transporte longitudinal de sedimentos y garantizar la entrada al puerto; (ii) dragados a una profundidad de agua menor de 8-9 m para garantizar la extracción de la arena interceptada; (iii) la consideración de estos depósitos como yacimientos sedimentarios estratégicos; y (iv) el derrumbe de la zanja a lo largo del puerto para retrasar la llegada de la arena a la bocana y así asegurar el libre acceso al puerto, This study is supported by the BEACHMED-e project, in particular, by the subprojects GESA and OpTIMAL. It is financed in part by FEDER, in part by cofinancing from the Generalitat de Catalunya

VII Congreso Geológico de España, 14-18 Julio 2008, Las Palmas de Gran Canaria

7 pages, 6 figures, This study was undertaken using shallow-water multibeam echosounder and a Geo-Pulse system. Five groups of morphosedimentary features are identifi ed regarding their genesis. In the infralittoral environment of the El Masnou coast, four of them represent sedimentary features (depositional, erosive, instability and hydrodynamic features) and the fi fth one is an anthropogenic feature. The depositional features comprise infralittoral wedges; the erosive features include furrows and terraces; the instability features are characterized by slides; the hydrodynamic features refer to fi elds of large- (hundreds of meters long) and small- (tens of meters long) scale wavy bedforms; and the anthropogenic features comprise trenches and pits related to successive dredges. The late Holocene stratigraphy of the infralittoral environment is defi ned by two major seismic sequences, lower and upper, each one formed by internal seismic units. The development of this stratigraphy and stacking patterns has been governed by sea-level changes. The stratigraphic division represents the coastal response to the last 4th order transgressive and highstand conditions, modulated by small-scale sea level oscillations (≈1 m - 2 m) of 5th to 6th order, The work was supported by INTERREG European Project Beachmed-e project and the “Generalitat de Catalunya”

VII Congreso Geológico de España, 14-18 Julio 2008, Las Palmas de Gran Canaria.-- 4 pages, 3 figures, [EN] This work presents a stratigraphic architectural synthesis of seven turbidite systems (Almeria, Calahonda, Sacratif, Fuengirola, Estepona, Guadiaro, and La Linea) developed in the northern sector of the Alboran Sea based on bathymetry data and high resolution seismic profiles. These turbidite systems represent depositional systems of the dimensions small (tens of kilometres). They develop in general from the shelf to basin. They show similar architectural elements (canyons, gullies, channel, overbank deposits, and lobe deposits) and their distribution and organization suggests lateral and longitudinal migrations related to different factors (gradient of the margin, sediment supply, tectonics, avulsion processes). This study indicates that they have been originated from the Lower Pliocene to Quaternary time (TS of Sacratif), Upper Pliocene to Quaternary time (TSs Almeria, Fuengirola, and Estepona) or exclusively during the Quaternary time (TSs Calahonda, Guadiaro and Linea). Based on morphologic configuration and feeder system, these systems are grouped into two models: a mud/sand rich point source model and a mud/sand-rich multiple –source submarine ramp model, [ES] Se presenta una síntesis de la arquitectura estratigráfica de siete sistemas turbidíticos (Almería, Calahonda, Sacratif, Fuengirola, Estepona, Guadiaro y La Línea) desarrollados en el sector septentrional del Mar de Alborán basada en datos de batimetría multihaz y perfiles de sísmica de alta resolución. Estos sistemas turbidíticos están localizados en tres sectores del Mar de Alborán (oriental, central y occidental) y representan sistemas deposicionales de dimensiones pequeñas (decenas de kilómetros) desarrollándose en general desde la plataforma hasta la cuenca. Muestran similares elementos arquitecturales (cañones, cárcavas, canal, depósitos de desbordamiento y lóbulo) y su distribución espacio/temporal refleja migraciones laterales y longitudinales relacionados con diferente factores de control (gradiente del margen, tectónica, aporte de sedimento, procesos de avulsión). Este estudio indica que se han desarrollado desde el Plioceno Inferior al Cuaternario (ST de Sacratif), desde el Plioceno Superior al Cuaternario (STs de Almería, Fuengirola y Estepona) o exclusivamente durante el Cuaternario (STs de Calahonda, Guadiaro y La Línea). Estos sistemas son agrupados en dos modelos en base al tipo de alimentación: tipo mono-alimentado fango arenoso y tipo en rampa poli-alimentado fango arenoso, La realización de este trabajo ha sido posible gracias a la ayuda económica proporcionada fundamentalmente por el Plan Nacional I+D+i a través de los proyecto SAGAS (ref: CTM2005-08071-C03-02/MAR). Asimismo, por la European Science Foundation a través del proyecto Westmed (Ref: 01-ELC-EMA22F) y finalmente por la empresa noruega Norsk-Hydro a través de varios convenios con el Instituto de Ciencias del Mar-CSIC de Barcelona. Se agradece a la empresa de Telefónica de España y al Consorcio Medgazz (Cepsa, Total Fina, Sonatrach y Snamprogetti-Eni) por apoyar los proyectos de investigación mencionados anteriormente a través de la figura de “Ente Promotor Observador” en el marco del Plan Nacional I+D+ i

VII Congreso Geológico de España, 14-18 Julio 2008, Las Palmas de Gran Canaria.-- 4 pages, 2 figures, [EN] This study was undertaken using shallow-water multibeam echosounder and a Geo-Pulse system. Five groups of morphosedimentary features are identified regarding their genesis. In the infralittoral environment of the El Masnou coast, four of them represent sedimentary features (depositional, erosive, instability and hydrodynamic features) and the fifth one is am anthropogenic feature. The depositional features comprise infralittoral wedges; the erosive features include furrows and terraces; the instability features are characterized by slides; the hydrodynamic features refer to fields of large- (hundreds meters long) and small- (tens meters long) scale wavy bedforms; and the anthropogenic features comprise trenches and pits related to successive dredges. The late Holocene stratigraphy of the infralittoral environment is defined by two major seismic sequences, lower and upper, each one formed by internal seismic units. The development of this stratigraphy and stacking patterns has been governed by sea-level changes. The stratigraphic division represents the coastal response to the last 4th order transgressive and highstand conditions, modulated by small-scale sea level oscillations (1-2 m) of 5th to 6th order, [ES] El presente estudio se ha llevado a cabo mediante datos obtenidos con sonda multihaz de aguas someras y un sistema de sísmica Geo-Pulse. En el ambiente infralittoral de la costa de El Masnou se han definido cinco grupos de elementos morfológicos en base a su génesis. Cuatro son de tipo sedimentario (deposicionales, erosivos, de inestabilidad, hidrodinámicos) y el quinto es de tipo antrópico. Las morfologías deposicionales comprenden cuñas infralitorales; las erosivas incluyen surcos y terrazas; las de inestabilidad están caracterizadas por deslizamientos; las hidrodinámicas se refieren a formas de fondo onduladas de escala grande (centenares de metros de longitud) y pequeña (decenas de metros de longitud); y las antrópicas comprende zanjas y hoyos de dragados. La estratigrafía del Holoceno superior del ambiente infralitoral está definida por dos secuencias sísmicas (inferior y superior), y cada una de ellas comprende internamente unidades sísmicas. El desarrollo de esta estratigrafía y su arquitectura han estado controlados por cambios del nivel del mar. Las divisiones estratigráficas definidas representan la respuesta costera al último estadio transgresivo y de alto nivel del mar de 4º orden, modulado por pequeñas oscilaciones ( 1-2 m) de nivel del mar de 5º y 6º orden, The work was supported by INTERREG European Project BEACHMED-e project and The Generalitat de Cataluña

Pranzini, E. ... et. al.-- 14 pages, 9 figures, 1 table

Preti, M. et. al.-- 12 pages, 16 figures, 2 tables

Alonso, Belén... et. al.-- 15 pages, 8 figures, 2 tables

VII Congreso Geológico de España, 14-18 Julio 2008, Las Palmas de Gran Canaria.-- 4 pages, 3 figures, [EN] The present study proposes a morphological evolution model of the sandy coastline Premià–El Masnou. It’s based on the wave climate establishment from WANA model data set, the textural and compositional analysis of superficial sediment samples and the study of several beach profiles and shoreline evolution from topo-bathymetries of the coastline achieved on november 2006 and may 2007. The sandy coastline Premià–El Masnou is exposed mainly to waves from NE-E sector and are identified two types of sediments: coarse sand with a low content of micas and medium sand with a high content ofmicas. Cross-shore, its observed erosion of the whole beach profile to NE and to SW, accumulation of sediment in the subtidal zone. Long-shore, shoreline is retreating in the NE end of beaches and advancing in the SW end. This results set carries us to include on the morphological evolution model, the rotation effect of embayed beaches by coastal infrastructures in relation to wave climate and also, a natural sand bypassing from beach updrift to the subtidal zone of El Masnou Marine, [ES] El presente estudio propone un modelo de evolución morfológica del tramo litoral Premià–El Masnou. Se ha realizado en base al establecimiento del clima marítimo con los datos de la red WANA, el análisis de textura y composición de muestras de sedimento superficial y el estudio de diversos perfiles de playa y de evolución de la línea de costa a partir de topo-batimetrías del tramo litoral realizadas en noviembre 2006 y mayo 2007. El tramo de costa Premià–El Masnou se encuentra expuesto principalmente al oleaje procedente del sector NE-E y son identificados dos tipos de sedimentos: arenas gruesas de bajo contenido en micas y arenas medias de alto contenido en micas. Transversalmente, se observa erosión de todo el perfil de playa hacia el extremo NE del tramo y hacia el SO, acumulación del sedimento en la zona submareal. Longitudinalmente, la línea de costa está retrocediendo en el NE de las playas y avanzando en el SO. Este conjunto de resultados nos lleva a englobar dentro del modelo de evolución morfológica, el efecto de rotación de las playas confinadas por infraestructuras costeras en relación al clima marítimo y también, el “bypass” natural de arena desde la playa situada aguas arriba hacia la zona submareal del puerto de El Masnou, Este estudio está financiado por el proyecto BEACHMED-e, en particular por los subproyectos GESA y OpTIMAL. Estan financiados por FEDER y la Generalitat de Catalunya. R. Durán agradece a la becas posdoctoral del MEC

14 pages, 5 figures, Hydrocarbon exploration and the ongoing assessment of potential seismic risks are the main drivers behind the high-resolution mapping of continental margins. The large volume of literature devoted to turbidite systems in particular shows the importance of detailed descriptions of their characteristics and overall geomorphological variability, primarily through the distribution of sediment facies. These descriptions rely mainly on acoustic measurements, which are notoriously difficult to interpret. Textural analyses quantify the second-order statistics of sonar imagery, detecting and quantifying details invisible to the human eye. We show the potential (and limitations) of this approach using high-resolution (6 m) towed ocean bottom instrument (TOBI) sidescan sonar imagery acquired in the Alborán Sea, south of Almería, Spain, during the high resolution imaging of Tsunamigenic structures (HITS) 2001 programme. The imagery is co-registered with EM-12 multibeam bathymetry, topographic parametric sonar (TOPAS) sub-bottom profiles, and localized ground truthing. Our study focuses on the Almería Canyon, a meandering channel system more than 57 km long and transporting large amounts of sediments from the coast down to the Alborán Trough, c. 1700 m deep. Textural analyses quantify the variations of sediment processes along the slope of the Almería Canyon. They agree with the results of previous studies, and they can be used to provide new insights into the dynamics and evolution of the canyon, J. Gonqalves, under the expert guidance ofT. LeBas (SOC) and with funding from the programme EASSS-III (European Access to Seafloor Survey Systems: grant HPRI-CT99-0047). The HITS survey also benefited from MCYT Acci6n Especial HITS REN2000-2150-E. O.G.S. is a European Marie Curie Fellow (grant HPMF-CT-2002-01970)