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UID/SOC/04647/2013 Em Maio de 2009, a Comissão de Limites da Plataforma Continental (CLPC), das Nações Unidas, recebia o Projeto de Extensão da Plataforma Continental (PEPC) de Portugal. Após um trabalho intensivo de recolha de dados científicos (sobre os fundos oceânicos e a biodiversidade marinha), o projeto nacional foi desenvolvido com o propósito de sustentar o alargamento da soberania nacional sobre o solo e o subsolo marinhos, além das 200 milhas marítimas, podendo a área marítima sob jurisdição portuguesa chegar aos 4 milhões Km2. Ainda que não se consiga, para já, avaliar a real dimensão das consequências da aprovação deste projeto, perspetivam-se oportunidades económicas, inerentes à exploração de recursos minerais, energéticos e genéticos. Ao nível das relações internacionais e diplomáticas, o projeto está igualmente associado ao reforço da centralidade atlântica do país, no contexto europeu. Procura-se, deste modo, fazer uma reflexão sobre as potencialidades do alargamento da plataforma continental de Portugal, assim como uma síntese do estado da arte sobre esta matéria. É ainda abordado o caso de Espanha, que submeteu, igualmente, à CLPC vários projetos para alargamento da sua área marítima. Por fim, enquadram-se estes projetos no Plano de Ação para uma Estratégia Marítima na Região Atlântica, aprovado pela Comissão Europeia, em 2013. publishersversion published

The oblique convergence of the tectonic plates with respect to the continental margins leads to the distribution of the deformation between raised zones and subsidence zones. In this context, vertical movements can be controlled by the structural inheritance and can influence the architecture of the sedimentary deposits of the continental shelf and the deep basin. Seismic reflection profiles and high resolution bathymetry allow to image the continental shelf and the deep basin. In the western Mediterranean, the African-Eurasian convergence and the back-arc context have controlled the deformation of the Alboran domain since the Miocene. The oblique convergence led to the formation of large transpressive structures crossing the Alboran basin and Miocene strike-slips faults reusing locally the boundaries of the thrust sheet set up during the Oligo-Miocene collision. Three aspects are developed in this thesis: 1) the characterization of the Pleistocene tectonic structures associated with the Nekor basin, a peripheral basin of the Alboran domain situated on its southern margin, with an emphasis on the importance of the alpine inheritance in the evolution of this basin, 2) the decoding of the architecture of the Nekor basin sedimentary platform, to propose an age model of deposited sequences for the last 500 000 years, demonstrating the influence of the tectonic segmentation of the margin on the geometry of the sedimentary platform, 3) the history of the evolution of folds and faults affecting the deep basin from the Pliocene and the chronology of the tectonic structures from the Messinian Salinity Crisis to present-day.; La convergence oblique des plaques tectoniques par rapports aux marges continentales conduit à la distribution de la déformation entre zones soulevées et zones en subsidence. Dans ce contexte, les mouvements verticaux peuvent être contrôlés par l’héritage structural et peuvent influencer l’architecture des dépôts sédimentaires de la plateforme continentale et du bassin profond. La sismique réflexion et la bathymétrie permettent d’imager les architectures des plateformes et du bassin profond. En Méditerranée Occidentale, la convergence Afrique-Eurasie et le contexte d’arrière-arc contrôle depuis le Miocène la déformation du domaine d’Alboran. La convergence oblique a conduit à la formation de grandes structures transpressives traversant le bassin et de couloirs décrochants Miocène réutilisant localement les limites des nappes chevauchantes mises en place lors de la collision Oligo-Miocène. Trois aspects sont développés dans cette thèse: 1) la caractérisation des structures tectoniques actives et Pléistocène associées au bassin de Nekor, un bassin périphérique du domaine d’Alboran situé sur sa marge sud, et la démonstration de l’importance de l’héritage Oligo-Miocène dans l’évolution de ce bassin, 2) le décryptage de l’architecture de la plateforme sédimentaire du bassin de Nekor, pour proposer un modèle d’âge des séquences de dépôts pour les derniers 500 000 ans, et enfin 3) la démonstration de l’influence de la segmentation de la marge par la tectonique sur la géométrie de la plateforme sédimentaire, l’histoire de l’évolution des plis et des failles décrochantes affectant le bassin profond depuis le Pliocène et la chronologie des structures décrochantes.

The aim of the paper is to evaluate and map changes in sea-floor elevation in a marine sandy epeiric environment as a tool in research on present-day sea floor sediment dynamics, especially of bank summits and swale floors, and to assess the mobility of banks and sand waves from sounding and hydrographie maps and from hypsometric profiles provided by sequential bathymétrie campaigns along fixed tracks. It provides a review of data acquisition techniques and data processing methods. It focuses on stability maps and on morpho- metric methods, especially on trend maps of elevation change. Superposed profiles and serial profiles allow to study in more detail the displacement of banks, the progression or retreat of bank flanks, sand-wave mobility and other related topics. It shows that each method has its own specific application field but that all are complementary. The paper presents numerous examples of application of different methods to the Flemish Banks. It also mentions the potential of new technologies developed since the 1990s: multi-beam bathymetry, local relief mapping and the interpretation of satellite images. It discusses the specific support of side-scan sonar to bathymétrie profiling and to echogram interpretation., Résumé L'article a pour but d'évaluer et de cartographier les tendances à l'abaissement et au rehaussement du fond marin dans un milieu épi- continental sableux, plus spécialement du sommet des bancs de sable et du fond des chenaux, et d'étudier la mobilité des formes à partir de campagnes bathymétriques séquentielles le long de lignes fixes. Il donne un aperçu des méthodes de traitement et des technologies de collecte de données, devenues disponibles au cours de la période 1980-1995, et par lesquelles une évaluation numérique est devenue possible. Il traite plus en détail de la carte de stabilité, ainsi que des méthodes morphométriques, dont celle des cartes de tendance du changement altimétrique, et livre une synthèse cartographique couvrant de longs suivis avec de très nombreuses données. Les profils superposés et les profils sériels servent surtout à étudier en détail le déplacement des bancs, l'avancement ou le recul des flancs, la mobilité des dunes hydrauliques et autres aspects spécifiques. L'article montre la complémentarité des différentes méthodes. Il présente de nombreux exemples d'application aux Bancs de Flandre pour la période 1987-1994. Il mentionne les possibilités des nouvelles techniques en voie de développement depuis 1995 (bathymétrie à l'écho-sondeur multi-faisceaux, levé de cartes de différences de hauteur, apport des levés au sonar à balayage latéral, interprétation d'images satellitaires) et montre aussi l'apport des levés au sonar à balayage latéral à la bathymétrie opérationnelle et à l'interprétation des échogrammes., De Moor Guy. Évaluation de la morphodynamique sous-marine en Mer du Nord méridionale au cours de la période 1985-1995 / Evaluation of sea-floor sediment dynamics in the Flemish Banks (southern North Sea) between 1985 and 1995. In: Géomorphologie : relief, processus, environnement, Avril-juin, vol. 8, n°2. pp. 135-150.

O mapeamento da Plataforma Continental Interna visando localização, qualificação e quantificação das reservas de material litoclásticos marinho possui poucos trabalhos relacionados. O Estado de Pernambuco sofre com erosões ao longo de todo seu litoral, e principalmente junto às cidades de Recife e Olinda. Assim, este estudo contribui tanto para o conhecimento da sedimentologia da plataforma continental interna adjacente ao Porto do Recife e à Praia dos Milagres em Olinda, quanto para a execução de futuras intervenções na recuperação das praias da região. Portanto, com objetivo de identificar áreas com concentrações de granulados litoclásticos marinhos compatíveis com especificações necessárias à regeneração de praias, foram analisadas 36 amostras, que foram coletadas ao longo de seis perfis equidistantes em 1 km, perpendiculares à linha de costa na plataforma interna do Porto do Recife. Em laboratório foram realizadas análises granulométricas e o estudo composicional de todas as amostras. Os resultados granulométricos mostram a predominância de sedimentos mal selecionados, ocorrendo classes variadas de tamanho entre seixo pequeno (8 mm) e lama (< que 0,062 mm), com predominância da fração areia grossa. A análise composicional revelou uma hegemonia de carbonatos marinhos. Os dados obtidos apresentam uma redução do suprimento sedimentar terrígeno local. Também de acordo com os resultados obtidos no presente estudo, a plataforma continental interna adjacente ao Porto do Recife e à praia dos Milagres em Olinda-PE, é essencialmente recoberta por areias biogênicas mal selecionadas, oriundas da morte e fragmentação dos organismos componentes dos recifes coralíneos e algálicos que ocorrem na plataforma continental interna. Dessa forma, esta área não possui material siliciclástico suficiente para ser utilizado na exploração mineral para recuperação artificial de praias no Estado de Pernambuco. There are few studies that map the Internal Continental Platform referring to localization, qualification and quantification of reserves of litoclastic marine material. The Brazilian state Pernambuco suffers from erosions along the whole coast and particularly in areas close to the cities of Recife and Olinda. This study offers new knowledge about the sedimentology of the internal continental platform adjacent to the harbor of Recife and the Beach Milagres in Olinda. Furthermore, it points out measures that can be used to recover regional beaches. Along 6 profiles with a distance of 1km and perpendicular to the coast line at the internal platform of the harbor of Recife, 36 samples were collected and analyzed. Thus, areas with concentrations of litoclastic marine aggregates with the necessary characteristics for the recovery of the beaches were identified. A laboratory was used for granulometry and a compositional study of all samples. The granulometric results show mainly badly selected sediments. There are different sizes from small pebbles (8 mm) to mud (< than 0,062 mm), predominantly coarse sand fraction. The compositional analysis reveals hegemony of marine carbonates. Thus the obtained data indicates a reduction of local terrigenous sedimentary supply. This is probably due to the fact that the selected area is undergoing an initial transgressive process. Also in accordance with the obtained results of this study, the internal continental platform adjacent to the harbor of Recife and the Beach Milagres in Olinda, Pernambuco, is mainly covered by badly selected biogenic sand which has its origin in the death and fragmentation of components of the coral reef of the internal continental platform. As a result the area is not indicated to mineral exploration for the artificial recovery of the beaches in the state of Pernambuco.

The interpretation of 64 seismic reflection profiles in the Algarve continental platform (36º 20'-37º 00' paralels and 7º 20'-8º 40' meridians) calibrated with five petroleum exploration wells, with the identification of the geometric relations between six Cenozoic seismic units (B to G) and tectonic structures, allowed the construction of sucessive time-isopach maps (twt/s) and detailed interpretation of the geologic evolution. Two major tectonic structures were identified: a) the Portimão-Monchique fracture zone (striking N-S); b) an off-shore NW-SE fault zone, probably the S. Marcos-Quarteira fault. This accident separates two tectonic domains: the western domain (with N-S and E-W predominant structures and, secondarily, NW-SE and NE-SW) and the eastern domain (dominated by WSW-ENE, NW-SE, NE-SW, NNE-SSW and NNW-SSE structures). A persistent halokinetic activity had two major moments: a) sin-C unit; b) sin- and post-E unit. An increasing flexuration of the margin was identified, with spacial and temporal variation of the subsidence. The tectonic regime is considered as generally compressive, but the interpretation of the successíve stress-fields is rendered dificult by the existence of tectonic sub-domains and evaporitic structures.

Una de las medidas transitorias para la lucha contra el cambio cli-mático es el almacenaje geológico del dióxido de carbono, que se ha demostrado científicamente posible, económicamente viable y medioambientalmente sostenible.La Unión Europea, en el estricto marco de sus competencias, ha adoptado una Directiva en la que establece el marco jurídico del almacenamiento geológico. Al-gunos de los espacios geológicos donde se regula esta posibilidad son la Zona Eco-nómica Exclusiva y la Plataforma Continental, donde la Unión Europea y los Es-tados comparten competencias, espacios a los que se dedican los análisis en este trabajo.Se estudian, pues, las compatibilidades del Derecho Internacional del Mar y de las obligaciones de los Estados y la Unión Europea en materia de protección medio-ambiental marina, en los tres estadios del proceso industrial: captura del dióxido de carbono, el transporte y la inyección geológica. One of the transitory measures for fight against the climate change has been the geologic storage of the dioxide of carbon. This measure has been dem-onstrated scientifically possible, economically viable and environmentally sustain-able.The European Union, in the framework of its competentes, has adopted a Di-rective on this topic. The EU Directive mentions the geologic spaces where this possibility is regulated, among them the Exclusive Economic Zone and the Continental Platform, where the European Union and the States have shared competences. In this article, the analysis is focused on these marine spaces.The author studies the compatibilities of the International Law of the Sea and of the obligations of the States and the European Union as regards to the marine environmental protection, in the three parts of the industrial processes: the CO2 captures, the transport and the geologic storage. Junta de Andalucía, P08-SEJ-3524