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    New palynostratigraphic data of the Irati (Assistência Member) and the Corumbataí formations, Paraná Basin, Brazil, and correlation with other south American basins

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    ABSTRACT: This research presents the palynostratigraphy of organic-rich shales from the Irati and the Corumbataí formations, Paraná Basin (PB), Southeastern Brazil, as part of an unconventional hydrocarbon source rock and CO2 reservoir assessment study. Thirty-four samples from the Corumbataí Formation and the Assistência Member of the Irati Formation were collected in the states of Goiás (northern border of the PB), São Paulo and Paraná (eastern and southern border of the PB, respectively). The acquired data allowed to establish a comprehensive palynostratigraphic study across the basin where a total of 18 pollen genera (34 pollen species), seven spore genera, four microplankton genera (1 species), and Chlorophyceae algae species where identified. The palynostratigraphic analysis also reveals a clear dominance of bisaccate pollen grains such as Corisaccites alutas, Lueckisporites virkkiae, and Weylandites lucifer. The Lueckisporites virkkiae zone was identified in the upper part of the Irati Formation (Assistência Member) and the lowermost part of the Corumbataí Formation, indicating a Kungurian to Roadian age for this part of the succession. Differences in the Guttulapollenites hannonicus and Tornopollenites toreutos biostratigraphic ranges, recovered in the Corumbataí Formation, suggest an earlier development of these species in the Paraná Basin during the middle Permian. Therefore, to evaluate the differences in the first occurrences of key species within the Paraná Basin, a close palynostratigraphic correlation between the main Guadalupian-Lopingian South American Gondwana basins is tentatively established.info:eu-repo/semantics/publishedVersio

    Reply to “Comment on «Stratigraphy of the Northern Pulo do Lobo Domain, SW Iberia Variscides: A palynological contribution» by Zélia Pereira et al. (2018) – Geobios 51, 491–506”

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    ABSTRACT: The main comments made by M.F. Pereira et al. to Pereira et al. (2018) relate to the discussion of the palynological age vs. U/Pb geochronological age based on detrital zircons, stating that “this discussion is inconsistent due to: (i) the impossibility that primary igneous ages in zircon grains would have been rejuvenated during Early Carboniferous low-grade regional metamorphism, and (ii) a wrong interpretation of the meaning and implications of maximal depositional ages derived from the youngest detrital zircon population”.info:eu-repo/semantics/publishedVersio

    Unlocking the Secondary Critical Raw Material Potential of Historical Mine Sites, Lousal Mine, Southern Portugal

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    ABSTRACT: A steady supply of mineral raw materials is vital for the transition to a low-carbon, circular economy. The number of active mines in Europe has severely declined over the last century and half, giving rise to many abandoned mining waste sites and corresponding geological heritage. Also, the rise in minerals demand for large-scale deployment of renewable energy requires the continued and steady availability of key minerals. The supply risk associated with unpredicted geopolitical events needs to be eliminated/mitigated. Historical mine waste sites are the answer but evaluating mine waste is a lengthy and costly exercise. The study, undertaken in the Lousal Mine, used small unmanned aerial systems (sUASs) to model and determine mine waste volumes by generating orthomosaic maps with quick, inexpensive, and reliable results. Calculated mine waste volumes between 308,478 m3 and 322,455 m3 were obtained. XRD and p-XRF techniques determined the mineralogy and chemistry of waste, which varied from mineralization and host rocks with hydrothermal alteration and numerous neogenic sulphates (mostly gypsum, rhomboclase, ferricopiapite, coquimbite, and jarosite) related with supergene processes and weathering. The study shows the viability of using these sUASs to successfully model historical mine waste sites in an initial phase and for future monitoring programs.info:eu-repo/semantics/publishedVersio

    First record of Permo-Triassic palynomorphs of the N'Condédzi sub-basin, Moatize-Minjova Coal Basin, Karoo Supergroup, Mozambique

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    ABSTRACT: ermian-Triassic ages have been identified for the first time in the Karoo Supergroup of the N'Condedzi sub-basin, Moatize-Minjova Coal Basin, Mozambique. This transition was identified in a coal exploration borehole that penetrated the Matinde and Cadzi formations. The top of the Matinde Formation is dated latest Permian (Lopingian), and the Cadzi Formation is attributed to Triassic based on palynostratigraphy. The Lopingian age is established by the identification of three palyno-assemblages: Assemblage L1 based on the first occurrence (FO) of Guttulapollenites pollen, Assemblage L2 is marked by the FO of Thymospora pseudothiessenii, and Assemblage L3 is defined by the FO of Osmundacidites senectus. Triassic palynomorphs were identified for the first time in Mozambique (Karoo basins). The data allowed the identification of three assemblages: Assemblage T1 defined by the FO of Densoisporites nejburgii of Induan age, Assemblage T2 is marked by the FO of Platysaccus queenslandi and assigned to the Olenekian age, and Assemblage T3 is defined by the FO of Samaropollenites speciosus and Enzonalasporites vigens, indicating a Carnian age. No Middle Triassic rocks were identified, and the early Triassic sediments are overlain by sedimentary rocks of Carnian age, a hiatus that may correspond to an important tectonic event with uplift and erosion. This tectonic event is also suggested by the occurrence of common reworked Permian palynomorphs in the Carnian sedimentary rocks. These new data constrain the age of the Karoo Supergroup formations of Mozambique and contribute to improve the palaeoecological, palaeoclimatic evolution, and the palaeogeographic position of the Karoo Mozambique basins within the Gondwana supercontinent.info:eu-repo/semantics/publishedVersio

    Enterprise Europe Network (EEN) : Notas para a preparação de relatórios de sustentabilidade : Informação de apoio às PME

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    RESUMO: A Enterprise Europe Network (EEN) é uma rede de serviços que tem como objetivo ajudar as empresas ou organizações a inovar e a competir no quadro internacional. As entidades que pretendam inovar, competir e estabelecer parcerias com as suas congéneres estrangeiras ou que necessitam também de instrumentos que lhes permitam avaliar o desempenho do seu modelo de negócio podem fazê-lo através desta rede. Das diversas possibilidades disponibilizadas pela EEN destaca-se a preparação de relatórios de sustentabilidade. Os relatórios de sustentabilidade e a EEN podem estar relacionados por diferentes maneiras uma vez que esta rede visa auxiliar as empresas ou organizações a tornarem-se mais competitivas e inovadoras por via da oferta de um conjunto de serviços e informações relevantes num quadro internacional. No âmbito da Sustentabilidade, a EEN permite a disseminação, em larga escala, de informação diversa, bem como das melhores práticas relacionadas com o desenvolvimento sustentável em diferentes áreas de atuação. No quadro da divulgação de informações do modelo de negócio, os relatórios de sustentabilidade são utilizados como uma ferramenta que permite avaliar e comunicar o desempenho ambiental, social e económico de uma empresa ou organização. A EEN pode fornecer orientações e recursos que permitem apoiar estas entidades a desenvolver os seus relatórios de sustentabilidade, garantindo que as informações relevantes sejam identificadas e divulgadas de maneira adequada e assertiva. Na partilha de boas práticas, a EEN atua como uma plataforma de divulgação de boas práticas entre as entidades, de experiências na implementação de medidas sustentáveis e dos resultados alcançados, também por via dos relatórios de sustentabilidade, servindo de inspiração a outras empresas a adotarem práticas semelhantes. Na componente da sustentabilidade, a EEN pode oferecer ainda um suporte e uma orientação para todas as entidades que tenham o objetivo de se tornarem mais sustentáveis, por via da divulgação de informações sobre regulamentações ambientais, incentivos governamentais, bem como através da identificação de estratégias de economia de recursos em diferentes áreas tidas como relevantes. Os relatórios de sustentabilidade podem ser uma ferramenta muito útil na avaliação do progresso e na identificação de novas áreas de atuação ou de áreas que podem ainda ser desenvolvidas. Esta informação permite também demonstrar o compromisso e o desempenho destas entidades, tornando-as mais resilientes e, consequentemente, mais atrativas para investidores, parceiros comerciais e clientes. No quadro do acesso ao financiamento e nas oportunidades de negócios, a rede EEN permite ainda identificar oportunidades de financiamento e de negócios. Assim, os relatórios de sustentabilidade e a EEN estão estritamente interligados no sentido de que esta rede internacional pode fornecer suporte, orientação e recursos às entidades que manifestem o compromisso em promover a sustentabilidade e que, tenham ainda como objetivo, a avaliação e a comunicação do desempenho do seu modelo de negócio nas mais diferentes áreas de atuação. O presente documento congrega um conjunto de informação objectiva, estruturada e orientada e que tem como principal objetivo apoiar as entidades na preparação de relatórios de sustentabilidade. Assim, na Secção 1 são apresentados os serviços disponibilizados pela EEN, bem como identificadas as principais vantagens e a relação de proximidade que existe entre a EEN e estas entidades e a sua relação (critérios, benefícios e obrigatoriedade) com as normas e indicadores - European Sustainability Reporting Standards (ESRS). Na Secção 2 são abordados os temas relacionados com as normas europeias, o seu enquadramento, transparência, comparabilidade e gestão de desempenho, identificando os principais requisitos, objetivos e os critérios, bem como identificados os Critérios Técnicos de Avaliação e os Objetivos de Desenvolvimento Sustentável no âmbito da Taxonomia da União Europeia. Na Secção 3 é apresentada a estrutura e as principais áreas de atuação das ESRS-ESG (Environmental, Social e Governance) e sua relevância, identificados os desafios e limitações, bem como as principais estratégias de superação dos desafios. Nesta secção são ainda assinaladas algumas limitações ao atual enquadramento normativo. Na Secção 4 são apresentadas as principais conclusões.N/

    The positive impact of biomineralization for marine corrosion protection of AA5083 alloy

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    ABSTRACT: This paper investigates, using surface characterisation techniques (SEM, XPS and ToF-SIMS), the impact of marine biological activity on AA5083 corrosion behaviour during seawater immersion. Different solar exposure (light vs. dark) results in distinct marine fouling development, influencing surface modifications. On the dark side, an Al/Mg oxide/hydroxide layer forms, allowing Cl - penetration. Pitting attack is observed after immersion. For the light side, a dual layer structure forms, with a hydrated Mg rich outer layer, showing barrier effect to Cl - penetration. No localized corrosion occurs. A comparison with abiotic conditions demonstrates the corrosion inhibiting effect of marine biological activity on AA5083.info:eu-repo/semantics/publishedVersio

    Enhancing microalgae biomass production: Exploring improved scraping frequency in a hybrid cultivation system

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    ABSTRACT: Recently, hybrid systems, such as those incorporating high-rate algal ponds (HRAPs) and biofilm reactors (BRs), have shown promise in treating domestic wastewater while cultivating microalgae. In this context, the objective of the present study was to determine an improved scraping frequency to maximize microalgae biomass productivity in a mix of industrial (fruit-based juice production) and domestic wastewater. The mix was set to balance the carbon/nitrogen ratio. The scraping strategy involved maintaining 1 cm wide stripes to retain an inoculum in the reactor. Three scraping frequencies (2, 4, and 6 days) were evaluated. The findings indicate that a scraping frequency of each 2 days provided the highest biomass productivity (18.75 g total volatile solids m(- 2) d(-1)). The species' behavior varied with frequency: Chlorella vulgaris was abundant at 6-day intervals, whereas Tetradesmus obliquus favored shorter intervals. Biomass from more frequent scraping demonstrated a higher lipid content (15.45%). Extrapolymeric substance production was also highest at the 2-day frequency. Concerning wastewater treatment, the system removed 93% of dissolved organic carbon and similar to 100% of ammoniacal nitrogen. Combining industrial and domestic wastewater sources to balance the carbon/nitrogen ratio enhanced treatment efficiency and biomass yield. This study highlights the potential of adjusting scraping frequencies in hybrid systems for improved wastewater treatment and microalgae production.info:eu-repo/semantics/publishedVersio

    Comprehensive Wheat Straw Processing with Deep Eutectic Solvent to Deliver Reducing Sugar

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    ABSTRACT: Pretreatment is one of the bottlenecks in the cost and energy-efficient biomass valorization. Deep eutectic solvents are potential candidates for being used to address these challenges. In this work, the deep eutectic solvent composed of choline chloride, and acetic acid was studied for its use in wheat straw fractionation. The pretreated biomass was assessed concerning the lignin and glucan content. Under optimized time and temperature conditions, defined using Doehlert matrix chemometric tool, of 3 h 47 min and 139.6 degrees C, the processed wheat straw contained as much as 42.5 +/- 0.42 wt.% and 38.59 +/- 1.26 wt.% of glucan and lignin contents, respectively. The need for biomass washing after the pretreatment with deep eutectic solvents and before the enzymatic hydrolysis step was also evaluated. The obtained enzymatic hydrolysis results, i.e., glucan to glucose yield of 27.13 +/- 0.25 vs. 25.73 +/- 0.08 for washed or unwashed biomass correspondingly, are equally good substrates. Fractal kinetic analysis of the data showed similar values of k and h for both glucose and xylose reactions between washed and unwashed biomass. This confirmed that biomass washing is an unnecessary step, which in turn opens room for biomass processing intensification.info:eu-repo/semantics/publishedVersio

    Critical raw materials in the global high-throughput ceramic industry

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    ABSTRACT: The high-throughput ceramic industry is exposed, at the global level, to the risk of shortage and/or sudden price growth of raw materials, particularly Critical Raw Materials (CRMs). The goal of the present study is to overview the dependence on CRMs of a sector transforming a large amount of mineral resources, i.e. the ceramic manufacturing and its supply chain (wall and floor tiles, sanitaryware and tableware, frits and glazes, pigments and inks, and so on). For this purpose, a critical assessment with expert consultation was carried out to quantify demand, uses, recycling and possible substitutes of CRMs. Such data allowed assessing the risk exposure for the ceramic industry at the global level, at the light of expected trends in production and demand for every CRM. The various subsectors into which the high-throughput ceramic industry is divided are exposed differently to supply risk. The production of inks, pigments, dyes and effects for ceramic decoration is mainly exposed to supply risk, and similarly that of frits, glazes and grinding media. End-users of these materials (in particular tile manufacturers) are equally exposed to risk, albeit indirectly. However, the direct use of CRMs in ceramic bodies occurs massively only for feldspar (in different percentages in wall and floor tiles, sanitaryware, and tableware). Other subsectors (silicate refractories and insulators, clay bricks and roof tiles, machinery components, etc.) do not make use of or only make occasional use of certain CRMs. The ceramic industry must implement actions to mitigate the different degrees of supply risk to which the CRM is exposed. The extreme risk (Cobalt and Praseodymium) makes it necessary to search for substitutes and technological solutions to reduce CRM consumption. These actions are also recommended in the case of high risk (Antimony and Lithium). The recommended actions to mitigate moderate risk (Barium, Bismuth, Borates, Feldspar, Tungsten, Vanadium and Yttrium) consist mainly of strengthening the supply chain and improving resource efficiency. No action appears to be necessary for low risk (Cerium, Manganese, Phosphate and Platinum Group), while no risk has been found for Fluorine and Niobium. To ensure the access to CRMs without disruptions, it is appropriate to envisage a medium-long term strategy, involving the various players in the ceramic supply chain.info:eu-repo/semantics/publishedVersio

    Biogas reforming as a sustainable solution for hydrogen production: Comparative environmental metrics with steam-methane reforming and water electrolysis in the Portuguese context

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    ABSTRACT: This study delves into the dynamics of hydrogen production, with a specific focus on biogas reforming (BGSMR) for hydrogen generation. It compares the environmental impact of this solution with hydrogen production from natural gas-steam reforming (NGSMR) and commercial electrolysis in the Portuguese context. Various metrics, including carbon footprint, water depletion, energy utilization, and waste valorization are employed for a comprehensive comparison. The assessment explores the impact of operational parameters and different off-gas combustion scenarios, incorporating water recycling practices. Due to challenges in obtaining detailed data on the actual reforming process, the study relies on process simulation techniques, primarily using DWSIM. Commercially available data for water electrolysers were used for comparison. In the context of decarbonizing power systems, hydrogen from water electrolysis emerges as a competitive option only in a scenario where the power system is 100% reliant on renewable sources, particularly with respect to the carbon footprint metric. Biogas systems, characterized by near-zero carbon emissions, stand out as a favourable option from the near future to the long run. This research contributes valuable insights into the dynamics of hydrogen production, shedding light on environmentally viable alternatives across a range of power system scenarios.info:eu-repo/semantics/publishedVersio

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