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- 1926 – 2021 flood impacts in Mozambique from a local database incidencePublication . Nganhane, Helio Vasco; Tavares, Alexandre; Santos, Pedro Pinto; Dgedge, GustavoABSTRACT: Due to its geographical location, Mozambique has been frequently affected by climatic events, in particular depressions, storms and tropical cyclones that often cause flooding processes. In the last 10 years, the frequency of these events has increased and consequently the social and economic losses have also been amplified. This work presents results from ongoing research to create a database, using local incidence analysis, collecting and evaluating impact associated with flooding processes. The database - relying on hemerographic information and cross-checking data from official reports and international databases - shows, for the period encompassing 1926 and 2021, 996 flood occurrences, where 3237persons lost their lives, 1510 people were injured, 2.821.639 people were displaced, and 10.604.520 were only materially affected. The southern and central Mozambique have been the most exposed regions to flood process. The analysis of these outputs improve the disaster risk management system in Mozambique.
- 19th -century environmental transformation of an industrialized estuary: the Avilés sedimentary record (Asturias, N Spain)Publication . Gardoki, Jon; Cearreta, Alejandro; García-Artola, Ane; Irabien, María Jesús; Gomez-Arozamena, Jose; Villasante-Marcos, Víctor; Quijada, I. EmmaABSTRACT: The Avilés estuary is one of the most important industrial ports in northern Spain, whose natural characteristics have been largely altered since the 1830s. Here, the environmental transformation of this estuary during the 19th century is explored using a multi-proxy approach including benthic foraminiferal content, sedimentology (grain-size), trace metals and short-lived radionuclides (210Pb and 137Cs) analysed from a 50-cm-long sediment core and a surface sample collected from the middle part of the estuary in the Pedro Menéndez Channel. The obtained results provide evidence that indicate an evolution from a naturally-driven environment with high a marine influence towards a more restricted setting under brackish conditions. The observed environmental change is interpreted as being mostly derived from physical modifications linked to the marsh reclamation and channelling starting in 1833 and intensified since 1860. This study provides a preindustrial environmental reference framework for future studies in coastal areas of the NW Atlantic Iberian margin.
- 87Sr/86Sr dating of the Alcácer do Sal Formation (upper Miocene, mainland Portugal)Publication . Ressurreição, Ricardo; Legoinha, Paulo; Dias, Ruben Pereira; Santos, José Francisco; Ribeiro, Sara; Patinha, Carla; Miranda, RuiThe Lower Tagus Basin was subjected to several marine transgressions along the Neogene, related to positive eustatic oscillations and also controlled by the regional tectonic activity. In the Alcácer do SalSines region, previous studies identified an episode of marine sedimentation interpreted as having occurred during the late Serravalian to early Tortonian interval, based on biostratigraphic data. This episode is represented in the Alcácer do Sal Formation. The study of the SMS-12- 01B borehole, drilled for mineral prospection purposes, located about 10 km NNE of Melides, allowed the identification of a 3 m thick layer of sediments containing marine fossils. 87Sr/86Sr determinations of oyster shells point to deposition about 11.5 Ma ago, validating previous proposals for the age of the formation. These data correspond to the first numerical ages obtained for the Alcácer do Sal Formation, allowing a solid correlation with other known marine units in the Lower Tagus and Algarve basins related to the same transgression episode
- An island of coal: the British National Coal Board and their 'Plans for coal' 1947 to 1987Publication . Vernon, RobertABSTRACT: By the end of World War II, the UK coal industry was in slow decline. It was revitalised in 1947, when it was nationalised, as the National Coal Board. The first 'Plan for Coal' and its revision were published in the 1950s. Modernising many collieries achieved an increase in coal production. Geological exploration also identified coal reserves for new deep collieries mainly in concealed measures that surrounded the existing coalfields. The Yom Kuppur war in 1973 highlighted how dependent the UK was on oil and gas from the Middle East. A balanced energy strategy was needed, that included increased coal production. The second 'Plan for Coal' was published in 1974. Geological exploration was concentrated on the concealed coalfields and the Selby mine complex, Yorkshire, was established. 'Plan2000' soon followed in 1978. It envisaged that extra coal production would be required by 2000. Exploration proved considerable coal resources, but by the end of the 1980s the use of coal was in decline and the industry was privatised. The study demonstrates how the 'Plans for Coal' increased our knowledge of coal geology and proved that the UK is indeed an 'Island of Coal.'
- Análogos geoquímicos portugueses de rochas e solos marcianos (S. Saturnino – Fronteira vs Cratera de Gusev e Meridiani Planum)Publication . Rocha, Carla; Alves, Eduardo IvoRESUMO: Este trabalho resulta de estudos petrográficos e geoquímicos feitos sobre afloramentos de rochas filonianas básicas na região de S. Saturnino (Fronteira, Portalegre, Portugal) como análogos de rochas e solos marcianos das regiões da cratera Gusev e de Meridiani Planum analisados nas missões dos rovers Spirit (MER-A) e Opportunity (MER-B). Mostra-se que este é o primeiro local em Portugal Continental que pode ser reconhecido como análogo dos ambientes geológico, petrográfico e geoquímico marcianos.
- Aplicação do método de resistividade elétrica na caracterização do calcário em exploração numa pedreira de rocha ornamentalPublication . Gomes, Alexandre; Duarte, João; Ribeiro, JoanaRESUMO: O principal objetivo deste trabalho foi a caracterização do maciço calcário explorado na pedreira “EM&R nº 6478”, com base na aplicação do método geofísico de resistividade elétrica, tendo em vista a otimização da operação extrativa de calcário para fins ornamentais. Pretende-se identificar as zonas do maciço com coloração acinzentada, que apresentam menor interesse económico. Verificou-se que os valores de resistividade elétrica sofrem variações significativas nas zonas de contato entre as zonas de coloração bege e as zonas de coloração acinzentada do calcário. Constatou-se que a tonalidade acinzentada se deve à presença de uma fração argilosa na sua composição, que pode explicar os valores mais baixos de resistividade elétrica. A metodologia utilizada revelou-se bastante eficaz no planeamento futuro da exploração, permitindo uma melhor orientação das frentes de desmonte, tornando a exploração ainda mais rentável.
- Áreas potenciais de Portugal para recursos minerais do domínio públicoPublication . Carvalho, Jorge; Filipe, Augusto; Lisboa, Jose; Xavier Matos, João Manuel; Batista, Maria Joao; Salgueiro, Rute; de Oliveira, Daniel Pipa Soares; Gonçalves, PedroRESUMO: O ordenamento do território é decisivo no processo de garantir o acesso aos recursos minerais. Durante os trabalhos para identificar as ações necessárias para a preparação da Estratégia Nacional para os Recursos Geológicos foi produzido um mapa de áreas potenciais em recursos minerais de Portugal. Constitui um ponto de partida para a implementação de uma metodologia vocacionada para a delimitação de áreas para a salvaguarda de recursos minerais.
- Arquivos de sondagens: responsabilidade científica e cultural. O exemplo da prospeção de lignites em Rio MaiorPublication . Soares, S.; Brandão, José Manuel Moraes ValeRESUMO: A Litoteca do LNEG é uma importante infraestrutura de apoio à investigação e ao desenvolvimento, onde se encontram arquivados cerca de 600 km de testemunhos de sondagens das diversas regiões do país. No presente artigo será efetuado o enquadramento relativo às sondagens de prospeção realizadas na região de Rio Maior durante os tempos áureos de prospeção de lignite nesta área, realçando os registos existentes no LNEG e a importância da sua manutenção para a Ciência e a Cultura.
- Aspetos microfaciológicos da formação da Leba, Proterozoico (Sudoeste de Angola)Publication . Duarte, Luis; Barata, Joao; Oliveira, C. L.RESUMO: A Formação da Leba é uma unidade carbonatada de referência do Proterozoico do Cratão do Congo, Sudoeste de Angola, composta por dolomitos silicificados com laminitos microbianos e estromatólitos. Este trabalho preliminar descreve as principais microfácies que caracterizam esta unidade, baseada no estudo de várias secções do Planalto da Humpata. Os resultados confirmam o domínio da dolomite em toda a sucessão, localmente fortemente silicificada. As fácies são bastante diferenciadas, compreendendo bioconstruções microbianas, incluindo micro domos estromatolíticos, e uma grande variabilidade de outras texturas, desde dolomicritos/mudstones a grainstones intraclásticos e extraclásticos. Tendo em conta que a dolomite é de origem primária, são identificados vários processos diagenéticos, incluindo dolomitização e diferentes fases de silicificação.
- Assessment of geomorphological diversity indices of Portugal mainlandPublication . Lopes, Catarina; Pereira, Paulo; Pereira, Diamantino; Gonçalves Teixeira, Zara FaniABSTRACT: The results from the assessment of diversity, evenness, and richness indices of geomorphology of mainland Portugal are presented, based on four hierarchical levels of geomorphological units. These indices were calculated on a hexagonal analytical grid, testing eight cell dimensions (1 km, 2 km, 5 km, 10 km, 15 km, 20 km, 25 km and 30 km). The 10 km dimension provided a clearer definition of regional geomorphological specificities, which correspond to areas of higher diversity and richness. The results related to evenness did not allow for establishing such clear relationships with geomorphological units. However, the diversity and evenness indices, along with richness, provide a more comprehensive assessment of spatial diversity. These results are part of the assessment of Portugal’s geodiversity and are essential for comparative analyses between various elements of geodiversity and with other natural and cultural elements.