Identificación de riesgos geoambientales y su valoración en la zona de hundimiento del buque Prestige

Potential geological hazard assessment has been carried out in the area where the Prestige vessel was sunk using a broad database that comprises: multibeam, high and ultra-high resolution seismic profiles, gravity cores, onland seismicity stations and Ocean Bottom Seismometers (OBS). The main results of this study indicate that among the geologic factors that can be considered as potential hazards, four main categories can be differentiated based on their origin: morphologic, sedimentary, tectonic, and seismicity. Hazards of morphologic origin include steep gradients; the morphologic features suggest the occurrence of mass-wasting instabilities. Hazards of sedimentary origin also includes the occurrence of slope instability processes in form of single slides and a great variety of erosive and depositional gravity flows (debris and turbidity flows). Hazards of tectonic and seismic origin are important because the sinking area straddles the Calida Bank which is a structural seamount with a moderate tectonic activity that results in a latent seismicity of low to moderate magnitude. The interaction of these factors leads to consider to the risk as medium, and the degree of exposure of the bow and stern as high. Several general and specific recommendations are made in order to increase the geological and geophysics knowledgement in the Prestige sinking area and Spanish continental margins and deep sea areas. These recommendations also should be used to elaborate the options for reducing the hazard and loss

Breve introducción a las razones para crear un TWG

7 pages, 3 figures[EN] CODIIGE (Executive Board of the Geographic Information Infrastructure of Spain) has created Thematical Working Groups (TWG) with the main objective of analyzing how apply the INSPIRE data specifications for transforming the Spatial datasets produced by Spanish public orgnizations and help them to be INSPIRE conformant and promote data interoperability. The mentioned TWG shall: CODIIGE (Executive Board of the Geographic Information Infrastructure of Spain) has created Thematical Working Groups (TWG) with the main objective of analyzing how apply the INSPIRE data specifications for transforming the Spatial datasets produced by Spanish public orgnizations and help them to be INSPIRE conformant and promote data interoperability. The mentioned TWG shall: – To study the data specifications for their correspondant INSPIRE theme and to produce a Technical Guide toe ase its national implementation. – To define the list of Spanish datasets to be considered its theme. – To analyze the datasets reported for its theme by public Spanish administration in order to decide its INSPIRE conformance and if they shall be included or not in the yearly monitoring.Regarding the TWG dealing with Annex III themes 15 Oceanographic Geographical Features and 16 Sea Regions, we have found some problems which are delaying the work: – The volunteer nature of the experts’ participation on the writing of the Technical Guides and the limited time available to do the work. – The fact that the INSPIRE specifications have been written by a reduced group of experts whutout representation from all the sector impled and we miss, for example, some features in the codelists, some oceanographic formats not included (NetCDF) or some not considered services like THREADDS.To conclude, we can say that the work of TWG 15 and 16 is very important and useful but, due to the founded problems, it is not being developped quickly enough[ES] El CODIIGE con el fin de promover la interoperabilidad de los CDE ha creado GTT con el objetivo principal de analizar cómo transponer las especificaciones de datos de la Directiva INSPIRE a los CDE creados por instituciones españolas y ayudarles a lograr su cumplimiento. Estos GTT deben: Estudiar las especificaciones de sus temas correspondientes INSPIRE y elaborar unas Directrices Técnicas para facilitar su implementación nacional. Definir los CDE incluidos en sus temas. Analizar los CDE informados por las distintas Administraciones Públicas, para decidir su conformidad con INSPIRE y si se incluyen o no en el seguimiento anual. En cuanto al GTT que se ocupa de los temas de 15 Rasgos Geográficos Oceanográficos y 16 Regiones Marinas del Anexo III de INSPIRE, este GTT se ha encontrado con problemas que están ralentizando su labor, como son: La naturaleza «voluntaria» de las personas que están trabajando en el desarrollo de las guías técnicas y el tiempo limitado asignado para realizar esta tarea. Que las especificaciones INSPIRE han sido producidas por un pequeño grupo de expertos voluntarios sin que estuviesen representados todos los sectores implicados, lo que complica su adaptación por falta de objetos en las listas de códigos, formatos de datos oceanográficos como NetCDF o servicios como THREDDS no contemplados, etc. Conclusión: el trabajo realizado por el GTT15 y 16 es necesario y útil, pero debido a los problemas encontrados, no se desarrolla con la suficiente rapidezPeer reviewe

Active faulting offshore SE Spain (Alboran Sea): Implications for earthquake hazard assessment in the Southern Iberian Margin

The southern margin of the Iberian Peninsula hosts the convergent boundary between the European and African Plates. The area is characterised by low to moderate magnitude shallow earthquakes, although large historical events have also occurred. In order to determine the possible sources of these events, we recently acquired swath-bathymetry, TOBI sidescan sonar and high-resolution seismic data on the Almería Margin (Eastern Alboran Sea). The new dataset reveals the offshore continuation of the NE–SW trending Carboneras Fault, a master fault in the Eastern Betic Shear Zone, and its associated structures (N150 and NS faults). These structures are active since they cut the Late Quaternary sedimentary units. The submarine Carboneras Fault zone is 100 km long, 5–10 km wide, and is divided into two N045 and N060 segments separated by an underlapping restraining stepover. Geomorphic features typically found in subaerial strike-slip faults, such as deflected drainage, water gaps, shutter ridges, pressure ridges and “en echelon” folds suggest a strike-slip motion combined with a vertical component along the submarine Carboneras Fault. Considering the NNW–SSE regional shortening axis, a left-lateral movement is deduced for the Carboneras Fault, whereas right-lateral and normal components are suggested for the associated N150 and NS faults, respectively. The offshore portion of this fault is at least twice as long as its onshore portion and together they constitute one of the longest structures in the southeastern Iberian Margin. Despite the fact that present day seismicity in the Almería margin seems to be associated with the N150 to NS faults, the Carboneras Fault is a potential source of large magnitude (Mw ∼7.2) events. Hence, the Carboneras Fault zone could pose a significant earthquake and tsunami hazard to the coasts of Spain and North Africa, and should therefore be considered in any hazard re-evaluation.Ministerio de Ciencia y TecnologíaEuropean CommissionEuropean Science FoundationGeneralitat de CatalunyaDepto. de Geodinámica, Estratigrafía y PaleontologíaFac. de Ciencias GeológicasTRUEpu

Acoustic and seismic imaging of the Adra Fault (NE Alboran Sea): in search of the source of the 1910 Adra earthquake

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