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La legislación pesquera española establece censos de buques pesqueros estructurados por caladero y modalidad (BOE, 2000). Se define “caladero” de pesca como un área geográfica sujeta a medidas de gestión o conservación singulares según criterios biológicos, mientras que se denomina “modalidad” a la forma de utilización de un determinado arte o aparejo. Cada modalidad cuenta con su correspondiente normativa, que determina las características técnicas de buques y artes o aparejos, así como las condiciones en que pueden utilizarse. En aguas bajo jurisdicción española se diferencian cuatro Caladeros Nacionales

Informe de Campaña de Geología y geofísica reconocimiento batimétrico mediante ecosonda multihaz., Informe de Campaña Bimbache 1011-Leg7 de Geología y geofísica .

Informe de Campaña de Geología y geofísica reconocimiento batimétrico mediante ecosonda multihaz., Informe de Campaña Bimbache 1011-Leg11 de Geología y geofísica

La Fase 2 de la campaña BIMBACHE 1011 tuvo como principal objetivo obtener información sobre el estado de los fondos y sus comunidades biológicas basado en la obtención de imágenes submarinas de la zona afectada por la reciente actividad volcánica. Se efectuó entre los días 27 de Octubre y 3 de Noviembre de 2011. Jefe de Campaña Francisco Sánchez, Inmersiones efectuadas con el ROV Liropus 2000 y el trineo de fotogrametría Politolana a bordo del B/O Ramón Margalef (IEO), I.E.O

Informe de Campaña Bimbache-1011 de Geología y geofísica: reconocimiento batimétrico mediante la ecosonda Multihaz EM-710 a bordo del B/O Ramón Margalef. El jefe de Campaña fue Juan Acosta, Informe de Campaña de Geología y geofísica: reconocimiento batimétrico mediante ecosonda multihaz., IEO

The sill of the Strait of Gibraltar is the morphological, oceanographical, and ecological gateway between the Atlantic Ocean and the Mediterranean Sea for the post-Messinian crisis period. The seabed is composed of synorogenic Betic-Rif clayey flysch overlaid by Pliocene and/or Quaternary calcareous conglomerates and coral accumulations, as well as current transported sand and mud in the deepest parts. The Strait of Gibraltar is one of the busiest maritime zones in the world and is thus affected by invasive species, but the benthic community is poorly studied. Furthermore, the study zone is affected by benthic trawl fisheries on the shelf and near-shelf areas and by the laying of submarine cables. Overall, the naturalness of the study area is considered to be largely unmodified. Based on the Benthic Terrain model scheme, a morphological classification has been made of the bathymetric MBES data, indicating several morphological habitats in the area that can cause fragmentation in the main ecosystem. This classification is based on the rugosity, slope, curvature, depth, bathymetric positioning index (BPI) with annulus neighborhood of 1,125, 300, 120, and 60 m, and the range of standard deviation of the depth over a distance of 45 m based on a bathymetric grid of 15 m. The predicted textural distribution map is based on the rugosity, slope, and objectively classified morphological zones identified in combination with textural information of the sampled stations used in a maximum-likelihood statistic algorithm provided by ArcGIS. Coral distribution is based on grab samples and the layers of the derived morphological grids.

Multibeam bathymetry, high (sleeve airguns) and very high resolution (parametric system-TOPAS-) seismic records were used to define the morphosedimentary features and investigate the depositional architecture of the Cantabrian continental margin. The outer shelf (down to 180–245 m water depth) displays an intensively eroded seafloor surface that truncates consolidated ancient folded and fractured deposits. Recent deposits are only locally present as lowstand shelf-margin deposits and a transparent drape with bedforms. The continental slope is affected by sedimentary processes that have combined to create the morphosedimentary features seen today. The upper (down to 2000 m water depth) and lower (down to 3700–4600 m water depth) slopes are mostly subject to different types of slope failures, such as slides, mass-transport deposits (a mix of slumping and mass-flows), and turbidity currents. The upper slope is also subject to the action of bottom currents (the Mediterranean Water — MW) that interact with the Le Danois Bank favouring the reworking of the sediment and the sculpting of a contourite system. The continental rise is a bypass region of debris flows and turbidity currents where a complex channel-lobe transition zone (CLTZ) of the Cap Ferret Fan develops. The recent architecture depositional model is complex and results from the remaining structural template and the great variability of interconnected sedimentary systems and processes. This margin can be considered as starved due to the great sediment evacuation over a relatively steep entire depositional profile. Sediment is eroded mostly from the Cantabrian and also the Pyrenees mountains (source) and transported by small stream/river mountains to the sea. It bypasses the continental shelf and when sediment arrives at the slope it is transported through a major submarine drainage system (large submarine valleys and mass-movement processes) down to the continental rise and adjacent Biscay Abyssal Plain (sink). Factors controlling this architecture are tectonism and sediment source/dispersal, which are closely interrelated, whereas sea-level changes and oceanography have played a minor role (on a long-term scale)., Sí

Four slides, the Ana, Joan, Nuna and Jersi slides, have been imaged on the seafloor along the Balearic margin of the Eivissa Channel in the western Mediterranean. They have areas of up to 16 km2 and occur in water depths ranging between 600 and 900 m. Volumes range from 0·14 to 0·4 km3. Their headwall scarps, internal architecture and associated deposits are characterized using a combination of swath bathymetry data and very high-resolution seismic reflection profiles. In general, they show horseshoe-shaped headwall scarps and distinct depositional lobes with positive relief. Internally, the slide bodies are mostly composed of transparent seismic facies. Chaotic facies are observed at the toe of some of the slides, and blocks of coherent stratified facies embedded in the slide deposit have also been identified. The reflection profiles demonstrate that the four slides share the same slip horizon, which corresponds to a distinctive continuous, high-amplitude reflector. Furthermore, the geometry of the headwall scars of the Nuna and Ana slides reveals evidence of pockmarks, and fluid escape features are also present further upslope. This indicates a possible link between fluid escape features and destabilization of the upper sediment layers. In addition, these well-characterized slides demonstrate the pitfalls associated with calculating the volume of the slide masses using headwall scarp heights and the assumed preslide seafloor topography in the absence of seismic data. The internal structure also demonstrates that transport distances within the slides are generally low and poorly characterized by headwall scarp to slide toe lengths., Sí

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The GEBRA '93 (Geological Evolution of the Bransfield Basin) survey was carried out in December 1993 in the Bransfield Strait (NW Antarctic Peninsula) and adjacent areas, onboard BIO Hespérides. The geophysical data acquired allow to characterize the morphostructure, sediment cover and magnetic anomalies of the SW-NE trending Central Bransfield Basin. Some transverse shifts and tresholds, together with alongbasin volcanic alignments, complicate the morphology and seismic structure of what otherwise would have been a long, continuous axial trough opened on a crust under extension. A major submarine valley, named Gebra Valley has also been identified, Sí

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La presente Tesis Doctoral lleva por t tulo Geodin amica del margen continental de Galicia: Estructura profunda y morfotect onica. Este estudio se aborda a partir de la integraci on de un gran volumen de nuevos datos geof sicos (gravim etricos, batim etricos y s smica de re exi on multicanal 2D y de ultra-alta resoluci on), procedentes de los proyectos ZEEE, ERGAP y BURATO4242. La nueva informaci on ha aportado constricciones muy relevantes sobre el origen, la estructura profunda y la complejidad siogr a ca del margen, as como sobre la caracterizaci on de la variaci on lateral de la transici on oc eano-continente. El margen continental de Galicia se clasi ca como un margen de rift pobre en magma. Este tipo de m argenes tienen dos rasgos comunes, que son: 1) Los pares de m argenes conjugados son asim etricos, teniendo uno de ellos una zona m as ancha de corteza extremadamente adelgazada, subrayada por un re ector s smico subhorizontal; 2) Entre la corteza continental adelgazada y la corteza oce anica normal, hay una zona de basamento compuesto por manto serpentinizado. La estructura del margen continental gallego es extremadamente compleja, re ejando la superposici on de varias etapas sucesivas de rift, y una etapa compresiva posterior que da como resultado la inversi on parcial del margen. Adem as, la proximidad de un punto triple de dorsal produce un cambio de orientaci on de las estructuras principales. Este margen continental ha sido ampliamente estudiado desde la d ecada de los '70. Sin embargo, la mayor parte de los estudios se han centrado en la parte occidental, existiendo una importante carencia de informaci on en los ancos norte y noroeste. Este hecho, junto con su gran complejidad estructural, ha provocado que no exista un modelo geodin amico previo que integre todos los procesos observados. Algunos aspectos, como son la transici on entre el margen oeste (extensivo) y el margen norte (compresivo), y la forma en que se produce su inversi on tect onica, apenas han sido abordados con anterioridad por la comunidad científica...