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- Carta geoambiental da região da Grande BeiraPublication . Oliveira, José Tomás; Milisse, Dino; Daudi, Elias Félix; Ramalho, Elsa; Fernandes, Judite; Quental, Lídia; Batista, Maria Joao; Dias, Ruben Pereira; Ussene, Ussene Vasco; Magaia, Almiro; Muchanga, André; Muchibane, Aníbal; Zeferino, Cátia Lídia; Balate, Gabriel; Gomane, Gertrudes; Cune, Grácio; Rebêlo, Luís Pina; Nave, Silvia; Manhiça, Vladimiro; Pereira, Aurete
- Variações da produtividade oceânica ao largo da Península Ibérica durante o MIS 5 e a sua relação com a Circulação Thermohalina = Open ocean productivity changes off Iberia during MIS 5 and its relation to the Atlantic Meridional Overturning CirculationPublication . Nave, Silvia; Lebreiro, Susana; Kissel, Catherine; Guihou, Abel; Figueiredo, M. Ondina; Silva, Teresa; Michel, Elizabeth; Cortijo, Elisa; Labeyrie, Laurent; Voelker, Antje H. L.O estudo mostrou que a produtividade oceânica ao largo da costa ocidental Portuguesa é maior durante as fases frias do Estádio 5 e durante os Estádios Glaciares 4 e 6, sugerindo uma maior disponibilidade de nutrientes durante esses períodos. Os dados de d13C, variações da granulometria e parâmetros magnéticos, sugerem correntes de fundo mais fortes durante os períodos frios, concordantes com uma maior contribuição das correntes de fundo austrais na margem Este do Atlântico Norte. Os nossos dados sugerem uma ligação entre a variação da produtividade oceânica e a circulação termohalina.
- Coastline evolution of the Portuguese south eastern coast: a high-resolution approach in a 65 years’ time-windowPublication . Nave, Silvia; Rebêlo, LuísAbstract. The coast, as the interface between land and sea, is a highly dynamic area, endangered by erosion and flooding, particularly at times of sea-level rise. At the present context of climate change, the use of scientific knowledge to understand coastal dynamics and coastal evolution assessment through time is essential to find a suitable management response for a successful adaptive coastal governance. It is proposed that the obtained high-resolution and long-term coastline change dataset is of crucial impor tance to improve the knowledge on mesoscale evolution of the Portuguese south-eastern coast, from Ancão to Vila Real de Santo António (VRSA), a 55 km long coastal stretch. The evolutionary trend, from 1950 to 2015, points to a general seaward progradation at the western (Barreta island) and eastern (Cacela peninsula – VRSA) sectors, and mostly an erosional trend at the central barrier island system (Culatra, Tavira and Cabanas islands). Moreover, a considerable average landward displacement of approximately 130 m is observed at Cabanas island. Regarding overall coastline movement, seaward displacement prevails, with a prograding coastline occupying approximately 54% of the studied sector even though this is mostly associated with human intervention on the coast. The exception is the Manta Rota - Monte Gordo sector where accumulation is likely related to natural processes. Considering the significant influence man-made interventions have had on the coastline evolution, it is believed that the natural evolutionary pattern would point to an overall erosional trend in the islands sector and a progradational trend from Manta Rota to VRSA beach.
- Testing rock magnetic and AMS method in tsunami and storm-induced depositsPublication . Font, Eric; Pires, Cristina Veiga; Ruiz Muñoz, Francisco; Pozo, Manuel; Abad, Manuel; Duarte, Sílvia; Simões, Nuno; Nave, Silvia; Costas, Susana; Rebêlo, Luís Pina
- Terrigenous biomarker record off Morocco over the last five glacial cyclesPublication . Rostek, Franke; Bard, Edouard; Nave, Silvia
- Sea surface temperature and oceanic productivity variations off the Iberian Margin during the last 20.000 yearsPublication . Alberto, Ana Isabel; Voelker, Antje H. L.; Nave, Silvia; Lebreiro, Susana
- Identification of tsunami deposits and their impact on coastal zones : a study case of the Boca do Rio estuary (Algarve, Portugal)Publication . Font, Eric; Pires, Cristina Veiga; Pozo, Manuel; Nave, Silvia; Costas, Susana; Ruiz Muñoz, Francisco; Abad, Manuel; Simões, Nuno; Duarte, Sílvia
- Long-term coastline evolution of Figueira da Foz - Nazaré sector (Portugal)Publication . Nave, Silvia; Rebêlo, LuísABSTRACT: ome sectors of the west Portuguese coast are particularly endangered by erosion and flooding. Regional to local scale information, on coastline evolutionary trend, is particularly valuable in sectors that includes areas with relevant erosion. A continuous, high-resolution, dataset on coastal evolution, from 1947 and 2015, between Figueira da Foz and Nazaré, was achieved within the Programme “Geological and Coastal Hazard Mapping at a 1:3000 resolution scale” at the National Laboratory of Energy and Geology (LNEG). This work, due to the detailed scale of analysis in a wide geographic context, allows to have both, a general overview of the coastal evolution and, at the same time, when zooming in up to 1:3000 scale, to observe the local behaviour and to quantify the occurred changes. Also, the well time-spaced aerial photograph dataset allows to compare the resultant coastline movement between the oldest and the youngest coastline (NSM index), with the total coastline oscillation (SCE index), bringing new insights on the coastline stability at a local scale. The evolution trend shows an overall erosional behaviour, if considering the entire sector. Erosion occurs predominantly in the north, as the south shows more stability and progradation. Quantification of the land-lost and land-gain due to the coastline shift in a 68-year period shows that 1 164 888 m2 of land were lost along 30 470 m of the coastal fringe, and 462 330 m2 were gained along an extension of 21 010 m.
- LUÍS REBÊLO : missão e dedicação ao litoral e aos sistemas dunaresPublication . Nave, Silvia; Monteiro, José HipólitoRESUMO: Luís Rebêlo foi o principal impulsionador, nas últimas duas décadas, da área de geologia costeira da Instituição onde trabalhou durante 33 anos nos Serviços Geológicos Portugueses. O seu abrupto falecimento veio provocar uma enorme perda e um dano de difícil reparação, dada a falta que faz um especialista consagrado em geologia costeira à Unidade de Geologia, Hidrogeologia e Geologia Costeira. Licenciou-se em Geologia pela Faculdade de Ciências da Universidade Clássica de Lisboa. O início da sua carreira profissional deu-se como Hidrogeólogo da PGIRH/T – Projecto Tejo, num breve período entre 1988 e 1989, data em que ingressou, como geólogo, e sob orientação de Hipólito Monteiro, no Departamento de Geologia Aplicada dos Serviços Geológicos de Portugal (SGP), da então Direcção-Geral de Minas e Serviços Geológicos. Em 1993, com a criação do novo Departamento de Geologia Marinha, transitou para esta unidade onde iniciou o seu percurso de investigação no domínio da Geologia Costeira.
- Paleoproductivity variations off Morocco during Interglacial periodsPublication . Nave, Silvia; Bard, Edouard; Rostek, Franke; Figueiredo, M. Ondina; Silva, Teresa