Browsing by Issue Date, starting with "2024-07"
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- El Complejo Calco-Alcalino de la Serra da Neve (SW Angola): trabajos en curso [Resumo]Publication . Prazeres, Cátia; Batista, Maria Joao; Lopes, R.; Barros, B.; Ferreira da Costa, P.; Labaredas, José; Guimarães, Fernanda; Rodrigues, José Feliciano; Cordeiro, DomingosRESUMEN: El Complejo Calco-Alcalino de la Serra da Neve (CACSN) constituye un conjunto de estructuras alcalinas volcánicas, subvolcánicas y plutónicas emplazadas en una tendencia general ONO-ESE a NOSE (Pereira y Moreira, 1978; Lopes y Caessa, 2021). Fue remapeado a escala 1:100.000 para la cartografía geológica del proyecto PLANAGEO y posteriormente fue una de las áreas seleccionadas para realizar exploración mineral para ETR-Nb-Ta a escala regional. Las campañas de campo incluyeron levantamientos con FRX portátil y SRG portátil, cuyos resultados mostraron patrones preliminares de distribución de ETR en las litologías del CACSN (Prazeres et al., en revisión). Los muestreos realizados durante el trabajo de campo permitieron estudios petrográficos y análisis con microsonda electrónica, que son la base para comprender la mineralogía de los ETR. Hasta ahora se ha demostrado que algunos carbonatos (bastnasita), fosfatos (apatito y xenotima), minerales de Zr (eudialita) y esfena incorporan cantidades apreciables de ETR, especialmente ETR ligeros.
- Catalogue of Cenozoic echinoid type specimens in the Geological Museum (Lisbon, Portugal)Publication . Pereira, PedroABSTRACT: The present catalogue lists the Cenozoic echinoid type specimens housed in the collections of the Geological Museum (Lisbon, Portugal). This material comprises a total of 69 type specimens (seven holotypes, one paratype, 52 syntypes, two lectotypes, and seven paralectotypes) of fifteen Miocene species from Angola and Portugal. Additionally, it is considered that Echinolampas (Echinolampas) maxima de Loriol, 1896 is a valid species and E. (E.) barcinensis Lambert, 1907 is its junior synonym.
- Economia do Hidrogénio Verde: Ferramentas para o Apoio à Decisão [Poster]Publication . Simoes, Sofia; Simões, Teresa; Quental, Lídia; Catarino, Justina; Amorim, Filipa; Brás, Teresa; Patinha, Pedro; Lopes, Tiago; Rodrigues, Carlos; Machado, Susana; Rangel, C. M.; Gírio, Francisco; Picado, Ana; Ponce Leao, Maria Teresa; Portillo, Juan C. C.RESUMO: O Hidrogénio (H2) Verde perspetiva-se como um vetor energético indispensável para alcançar a neutralidade carbónica em 2050, porém a economia deste vetor está em desenvolvimento e os agentes económicos precisam de fontes de informação confiáveis e ajustadas ao contexto nacional e Europeu. Neste sentido, o LNEG desenvolve investigação em vários domínios relacionados com o H2 verde, desde o estudo e desenvolvimento de processos de produção eficientes até a análise e modelos de negócios para estudar a viabilidade económica das cadeias de valor, passando pela análise de políticas públicas e ao mesmo tempo fornecendo informação de alto valor acrescentado para o apoio à decisão de entidades públicas e privadas. Com o objetivo de estabelecer pontes entre a investigação e a economia do H2 verde foram criadas ferramentas associadas à avaliação de projetos presentes e futuros em todas as cadeias de valor relacionadas. Uma destas ferramentas é o Atlas Nacional do H2 Verde Sustentável (LNEG, 2022) disponível para o público desde 2022 e que está a ser atualizado para incorporar os custos de produção, transporte e distribuição do hidrogénio verde em Portugal. O LNEG participa em importantes agendas mobilizadoras, como a Moving2Neutrality (LNEG, 2023) ou a H2Driven (LNEG, 2024), as quais abordam o desafio da transição energética no setor dos transportes, produzindo combustíveis sustentáveis, com um foco no hidrogénio e e-combustíveis verdes. O LNEG está a desenvolver um simulador de custos nivelados do hidrogénio incluindo todas as fases da cadeia de valor (produção, armazenagem, distribuição e transformação) produto da investigação do LNEG com os parceiros da agenda e que será disponibilizado em 2024 para o público geral. Este Poster apresenta o trabalho desenvolvido e em curso para estas ferramentas.
- The H2Excellence Project: Fuel Cells and Green Hydrogen Centers of Vocational Excellence towards affordable, secure, and sustainable energy for Europe [Resumo]Publication . Gano, António; Pinto, P.J.R.; Esteves, M. Alexandra; Rangel, C. M.ABSTRACT: The demand for green hydrogen (H2) and related technologies is expected to increase in the coming years mainly framed by drivers such as climate change and energy security of supply amid the European and global energy crises. REpowerEU Plan called for an intensification of hydrogen delivery targets, that will bring large-scale adoption of hydrogen production and applications in various sectors, stressing the need for a skilled workforce in the emergent hydrogen markets. To that end, the Erasmus+ European H2Excellence transnational project[2] has gathered 24 partners across the EU, to establish a Platform of Vocational Excellence in the field of fuel cells and green hydrogen technologies, with an educational and training offer that will tackle identified skill gaps and implement life-long learning opportunities. The project aims to become a benchmark in training and knowledge transfer, contributing to the integration of quality employment into green hydrogen local innovative systems approaching the entire hydrogen value chain.
- Posibles aplicaciones industriales de las arenas del Kalahari de Angola [Resumo]Publication . Lisboa, Jose; Oliveira, Álvaro; Rodrigues, José Feliciano; Fernández, J.; Manuel, JoséRESUMEN: Las arenas de color amarillo ocre con poca o ninguna matriz procedentes de la Formación Arenas Ocres (Mio-Plioceno) y las arenas lavadas de colores claros del Cuaternario (Oliveira y Sousa, 2021), presentes en la cuenca del Kalahari, se extienden sobre una vasta área en el SO de Angola, presentando una gran homogeneidad en todos los niveles a lo largo de esa cuenca. Sin embargo, muestran características morfológicas similares a las de las arenas del desierto y, como tales, no son adecuadas para usos más comunes en la obra civil, como el agregado de cemento. Son arenas de tamaño de grano generalmente < 1 mm, con predominio de fracción fina (125-250 μm), subangulares a subredondeadas, de tendencia bimodal, bien calibradas, con un contenido de matriz generalmente ≤ 7%. Están formados por granos de cuarzo, escasos minerales máficos u otros, dando como resultado una composición química con SiO2 > 98.5% y un reducido contenido en elementos penalizadores. Considerando la granulometría y el análisis químico, estas arenas tienen posibles usos en sectores de la industria cerámica y del vidrio, dependiendo, para aplicaciones menos exigentes, de métodos de beneficio sencillos, en particular para reducir el contenido de alúmina y especialmente de óxidos de hierro concentrados en los recubrimientos que a menudo afectan parcialmente a los granos. Estos pueden reducirse mediante lavados y tratamientos simples de fricción.
- Zircon U-Pb and Lu-Hf isotopes reveal the crustal evolution of the SW Angolan Shield (Congo Craton)Publication . Ferreira, Ezequiel; Lehmann, Jeremie; Rodrigues, José Feliciano; Hayes, Ben; Merino-Martinez, Enrique; Milani, Lorenzo; Bybee, Grant M.; Smith, Trishya M. Owen; García-Lobón, J. L.; Tassinari, Colombo C. G.; Ueckermann, Henriette; Sato, Kei; Silva, Paulo Bravo; Correia, João; Labaredas, José; Duarte, Laurent; Molekwa, Mmasetena Anna; Manuel, José; Victorino, Américo da MataABSTRACT: The crustal evolution of the Angolan Shield (AS) remains poorly constrained. To address this, we analysed U-Pb and Lu-Hf isotopes in detrital and igneous zircons to investigate the age and provenance of extensive sedimentary strata in southwestern Angola and use it as a proxy to gain insight into the Archean to Mesoproterozoic evolution of the region. Mesoproterozoic maximum depositional ages for the Iona (<1323 +/- 13 Ma), Ompupa (<1215 +/- 13 Ma), and Cahama (<1184 +/- 23 Ma) siliciclastics challenge previous correlations with the Paleoproterozoic Chela Group. Provenance analysis reveals that the Mesoproterozoic strata were derived internally from the AS. Our combined dataset indicates that the widespread Eburnean magmatism (-2.05-1.93 Ga) resulted from reworking of Archean crust, possibly in collision orogens. A major increase in the eHf(i) and eNd(i) values at - 1.87-1.73 Ga indicates a change in geodynamics, with magmatism of the Epupa-Namibe Metamorphic Complex (ENMC) generated in an extensional accretionary orogen at the southern margin of the Eburnean-Archean crustal block. Magmatism resumed in the Mesoproterozoic (-1.56-1.50 Ga), with suprachondritic eHf(i) values indicating significant juvenile addition. The Kunene Complex (KC: -1.50-1.36 Ga) anorthosite-mangerite-charnockite-granite magmatism displays variable eHf(i) and eNd(i) values, consistent with mixing between reworked ENMC-crust and juvenile melts in a long-lived accretionary orogen back-arc region. Post-KC (-1.36-1.30 Ga) magmatism shows an increased juvenile contribution, potentially linked to partial melting of ENMC and - 1.56-1.50 Ga juvenile crust during an orogenic event, or alternatively, related to renewed slab retreat and back-arc extension. The Hf isotopic compositions of - 1.29-1.18 Ga zircons are compatible with a renewed input from the depleted mantle and/or reworking of the earlier - 1.56-1.50 Ga juvenile crust. Emplacement of - 1.13-1.10 Ga mafic dikes/sills marks the end of Mesoproterozoic magmatism in the AS. Our new data enhance our understanding of the Archean to Mesoproterozoic crustal evolution of the AS.
- Mapas de potencial mineral en el sur de Angola: el primer enfoque de un mapa de prospectividad basado en datos y conocimiento adquirido en la región de Au-Fe del sur de Angola [Resumo]Publication . Batista, Maria Joao; Martín-Méndez, I.; Merino-Martínez, E.; Prazeres, Cátia; Cuervo, I.; Manuel, José; de Oliveira, Daniel Pipa Soares; Rodrigues, José Feliciano; García-Lobón, J. L.RESUMEN: Los mapas de recursos minerales a escala 1:50.000 fueron realizados en la última fase del Proyecto PLANAGEO con el objetivo de evaluar el potencial mineral de la región sur de Angola. Los objetivos elegidos fueron, entre otros, las zonas que contienen Au-Fe en las áreas de Jamba-Cassinga-Tchamutete, Chipindo y Cuima-Samboto. Los mapas integraron mapas geológicos, datos magnéticos y radiométricos aéreos y resultados de FRXp de campañas de campo de PLANAGEO y yacimientos minerales conocidos. Se obtuvieron análisis univariantes, bivariantes y multivariantes y grupos de pathfinders, tales como: Factor 1 (F1)- Cd, Hg, Fe2O3, As, V, Ni de rocas en Chipindo o Factor 1(F1) - Fe2O3, As, Sn, Sb, Ta en rocas de Jamba. Esos grupos fueron identificados como pathfinders de Au, representados en los Mapas de Potencial por encima del percentil 80. En el caso de Jamba era >0,838 y el área delimitada incluía rocas BIF, rocas metavolcánicas bimodales del terreno Arcaico del Grupo Jamba.
- Marine biomineralization for enhanced corrosion resistance: Insights from the ANR MICOATEC project [Poster]Publication . Marques, Maria João; Nkoua, C.; Jaume, Julien; Diderot, Anthony; Mercier, Dimitri; Seyeux, Antoine; Délia, Marie-Line; Silva, S. da; Fori, B.; Blanc, C.; Zanna, Sandrine; Marcus, Philippe; Basseguy, RegineABSTRACT: Concerns about marine pollution and ecological threats caused by traditional corrosion protection technologies have driven the development of new environmentally friendly anti-corrosion solutions. In recent years, it became clear that microorganisms have the potential to positively impact corrosion behavior, a phenomenon known as MICI (microbiologically influenced corrosion inhibition) [1,2]. Although research on MICI mechanisms is still in the beginning, two main mechanisms have been outlined: direct and indirect inhibition. In the first one, the microorganisms are responsible for the segregation of slow-release inhibitors or surfactants or consume oxygen, which affects the cathodic reaction process. The second one, indirect inhibition mechanism, is associated to the formation of a protective layer on the surface of the material due to metabolic activity of microorganisms. In this context, biomineralization attracted the attention of researchers as a solution to inhibit metal corrosion.
- Towards climate adaptation: a case study of a Coastal City in PortugalPublication . Aelenei, Laura Elena; Viana, Susana; Simões, Teresa; Amorim, Filipa; Simoes, Sofia; Barbosa, Juliana; Justino, Paulo Alexandre; Dinis, J.; Fernandes, G.ABSTRACT: The importance of climate-neutral and smart cities was addressed by the European Commission (EU) through the financing program EU Missions, as a response to the urban and energy challenges to promote innovative solutions and strategies and to deliver tangible results by 2050. To manifest their Expressions of Interest to join the EU Cities Mission, several cities across Europe applied for funding to support their local action plans toward reaching climate neutrality by 2030/2050. One example is the research European project Re-Value focusing on waterfront cities and aiming to transform the waterfront cities zones from a risk to an opportunity, through a New European Bauhaus (NEB) inspired value and impact model that allows urban transformation strategies to value quality and other non-monetary benefits in addition to (only) pricing and GHG emission reductions. This paper presents the results of the preliminary analysis developed in one of the 9 cities of the project, Cascais, located on the Portuguese coast. The results will contribute to a detailed roadmap actions and update of the Cascais long-term Territorial Transformation Plans to accelerate its journey to climate neutrality by 2050. As one of Cascais ambitions and main point of the developing roadmap is the adoption of the decentralised renewable energy generation, a spatial analysis of the potential for wind energy and solar PV energy in rooftops along with the wave energy potential assessment along the coast was done. In addition, a Decision Support Tool (DST) using the most relevant Key Performance Indicators (KPIs) for energy transition was used, to support Cascais implementation of the measures that will have the highest impact in inhabitant’s lives. The tool enables to evaluate how KPI’s from different sectors will evolve considering three different socioeconomic development scenarios.
- Modelización magnética del Complejo de Cunene (SW Angola) [Resumo]Publication . Mochales, Tania; Merino-Martínez, E.; Rey-Moral, Carmen; Machadinho, Ana; Carvalho, João; Represas, Patricia; García-Lobón, J. L.; Feria, María Carmen; Martín-Banda, Raquel; López-Bahut, T.; Alves, Daniela; Ramalho, Elsa; Manuel, José; Cordeiro, DomingosRESUMEN: El Complejo de Cunene (CC) representa un extenso macizo ígneo mesoproterozoico compuesto por rocas anortosíticas, gabroicas y ácidas contemporáneas, que aflora 18.000 km2 en dirección NNE-SSW desde el SW de Angola al NW de Namibia. Se han interpretado y modelizado en 2,5/3D los datos aerogeofísicos obtenidos en el proyecto PLANAGEO para investigar los límites no expuestos del CC, reconstruyendo la estructura de la corteza superficial bajo la cobertera del Kalahari. Gracias a la modelización se descifra una geometría lobular cuya extensión es casi tres veces la superficie aflorante y superior a la estimada mediante gravimetría (45.000 km2; Rey-Moral et al., 2022). Las anomalías magnéticas identificadas definen cuerpos individuales que conforman diversos pulsos magmáticos coalescentes durante el Mesoproterozoico. Las lineaciones magnéticas indican grandes sistemas de cizallamiento desarrollados en varias fases intrusivas en un contexto colisional de arco. Los lineamientos magnéticos al E sugieren un emplazamiento asociado a etapas transtensivas. Al W, con los pulsos más jóvenes, se detectan lineamientos en un régimen contraccional complejo. Estructuras tardías NNW-SSE extensionales, involucran magmas mantélicos y cuencas mesoproterozoicas tardías (<1,33 Ga).