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O registo fóssil de vertebrados continentais de Pombal: contributo para o conhecimento das faunas do Jurássico Superior da Bacia Lusitaniana
No full textABSTRACT: The presence of dinosaur remains is known in the region of Pombal since the end of the 19th century. The Andrés fossil site is one of the most significant paleontological localities currently known in this region, having yielded an unusually rich and diverse assemblage of vertebrates, including actinopterygians, lepidosaurs, crocodyliforms, pterosaurs, dinosaurs (ornithopods, sauropods and theropods), and mammals. In the last decades, the discovery of other localities with remarkable record of dinosaurs, especially sauropods, underlain the importance of this region for better understanding the continental faunas that inhabited this sector of the Lusitanian Basin during the Late Jurassic. This fossil record is particularly relevant for testing the possible existence of paleoenvironmental constrains in the distribution of some vertebrate taxa in different areas of the basin.RESUMO: A presença de restos osteológicos de dinossáurios é conhecida na região de Pombal desde finais do século dezanove. A jazida de Andrés é atualmente um dos locais paleontológicos mais relevantes conhecidos nesta região, tendo proporcionado um abundante e diversificado conjunto de fósseis de vertebrados, incluindo actinopterígios, lepidossáurios, crocodiliformes, pterossáurios, dinossáurios (ornitópodes, saurópodes e terópodes) e mamíferos. Nas últimas décadas, a descoberta de outros locais com notável registo de dinossáurios, particularmente saurópodes, salienta a importância desta região para o conhecimento das faunas que habitaram este setor da Bacia Lusitaniana durante o Jurássico Superior. Estes registos são particularmente relevantes para testar a possível existência de restrições
paleoambientais na distribuição de algumas faunas de vertebrados em diferentes áreas da Bacia Lusitaniana
First record of trilobites from the Silurian of Portugal (Moncorvo Syncline)
No full textRESUMO: A ocorrência de fósseis de trilobites em Portugal é conhecida desde há mais de 150 anos, mas permanecia por comprovar a presença deste grupo nas litologias do Silúrico. Reporta-se agora o primeiro registo de trilobites no Silúrico de Portugal, numa sucessão de intercalações de argilitos e calcários da Formação Campanhó do Sinclinal de Moncorvo. As trilobites são raras, estando a associação amplamente dominada por equinodermes scyphocrinitídeos, com cefalópodes nautiloides ortocónicos, tendo ainda sido registado um único fóssil de bivalve, Panenka?, constituindo também o primeiro registo do grupo no Silúrico da região. Do ponto de vista sistemático, foi possível identificar o encrinurídeo Cromus sp. e os phacopídeos Ananaspis? e Denckmannites?. Não obstante a identificação em nomenclatura aberta, o material português apresenta maior semelhança com as espécies-tipo destes géneros, respetivamente Cromus intercostatus, Denckmannites volborthi e Ananaspis fecunda, as três identificadas na Formação Kopanina do Ludlow da Chéquia, sugerindo a mesma idade para os níveis estudados. Os novos dados estreitam a relação deste setor da Zona Centro-Ibérica com as faunas bentónicas silúricas de afinidades boémicas, já reconhecidas no NO de Espanha, Pirenéus, Catalunha e na Zona de Ossa Morena, sendo distintas da restante Zona Centro-Ibérica e semelhantes ao norte de África e Boémia.ABSTRACT: The abundance of trilobite fossils in Portugal has been known for over 150 years, but the presence of the group in the Silurian remained to be evidenced. Here we report the first record of trilobites in the Silurian of Portugal, in a succession of shales intercalated with limestones belonging to the Campanhó Formation of the Moncorvo Syncline. Trilobites are rare, and the assemblage is largely dominated by scyphocrinitid echinoderms, with orthoconic nautiloid cephalopods and a unique record of the bivalve Panenka?, constituting the first record of the group in the Silurian of this region. From a systematic point of view, it was possible to identify the encrinurid Cromus sp. and the phacopids Ananaspis? and Denckmannites?. Despite the open nomenclature, the Portuguese material is more similar to the type species of these genera, Cromus intercostatus, Denckmannites volborthi and Ananaspis fecunda, respectively, all from the Kopanina Formation from the Ludlow of Czechia, suggesting the same age for the levels studied. The new data strengthen the relationship between this sector of the Central Iberian Zone and the Silurian benthic faunas with Bohemian affinities already recognised in NW Spain, the Pyrenees, Catalonia and the Ossa-Morena Zone, being distinct from the rest of the Central Iberian Zone and similar to North Africa and Bohemia
Analysis of Techno-Economic and Social Impacts of Electric Vehicle Charging Ecosystem in the Distribution Network Integrated with Solar DG and DSTATCOM
No full textABSTRACT: In this work, a comprehensive planning framework for an electric vehicle charging ecosystem (EVCE) is developed, incorporating solar distributed generation (DG) and a distribution static compensator (DSTATCOM), to assess their long-term techno-economic and environmental impacts. The optimal locations and capacities of the EVCE, solar DG, and DSTATCOM are determined using an improved particle swarm optimization algorithm based on the success rate technique. The study aims to maximize the technical, financial, and social benefits while ensuring that all security constraints are met. To assess the financial viability of the proposed model over a 10-year horizon, a detailed economic analysis comprising installation cost, operation, and maintenance cost is conducted. To make the model more realistic, various practical parameters, such as the inflation rate and interest rate, are incorporated during the financial analysis. Additionally, to highlight the societal benefits of the approach, the study quantifies the long-term carbon emissions and the corresponding cost of emissions. The proposed framework is tested on both a 33-bus distribution network and a 108-bus Indian distribution network. Various planning scenarios are explored, with different configurations of the EVCE, solar-based DG, and DSTATCOM, to assist power system planners in selecting the most suitable strategy
Characterization of theropod tracks in the upper Oxfordian of Cabo Mondego, Lusitanian Basin
No full textRESUMO: São analisadas dez pegadas de dinossauros, ocorrendo em dois estratos do topo das “Camadas com Pholadomya protei” (Oxfordiano superior) do Cabo Mondego (Figueira da Foz), sector norte da Bacia Lusitânica. Trata-se de pegadas que podem ser observadas na superfície das camadas ou em seção transversal, por vezes representando estruturas que deformam muito o substrato. O material icnológico encontra-se distribuído em duas camadas sucessivas, cada uma constituída por uma base de marga arenosa e topo de arenito de grão muito fino a médio. Os depósitos destas camadas correspondem a um ambiente litoral de planície de maré, num delta.ABSTRACT: Ten dinosaur footprints are analysed, occurring in two layers of the top of the Pholadomya protei layers (Upper Oxfordian) of Cabo Mondego (Figueira da Foz), northern sector of the Lusitanian Basin. These are tracks that can be observed on the surface of the layers or in cross-section, sometimes representing structures that greatly deform the substrate. The ichnological material is distributed in two successive layers, each consisting of a sandy marl base and a very fine to medium grain sandstone top. The deposits of these layers correspond to a tidal plain coastal environment
in a delta
Wasp cocoons from paleosols in the “Senhora das Necessidades Limestones” (Oligocene, Setúbal Peninsula)
No full textRESUMO: Em Portugal, os estudos de Icnologia de paleossolos estão a dar os seus primeiros passos. Neste trabalho descrevemos os casulos de vespas do tipo Fictovichnus sciuttoi identificados no Oligocénico dos “Calcários de Senhora das Necessidades” e provenientes de paleossolos carbonatados (Icnofácies de Celliforma). A descrição destes icnofósseis, que são um contributo para o conhecimento da biodiversidade do Oligocénico português, baseia-se numa pequena coleção localizada na Coleção Estratigráfica do Museu Geológico.ABSTRACT: In Portugal, the studies on the ichnology of paleosols are giving the very first steps. Here we describe the wasp cocoons Fictovichnus sciuttoi found in the Oligocene of “Calcários de Senhora das Necessidades” and derived from carbonate paleosols (Celliforma Ichnofacies). The description of these trace fossils, which represent a contribution for the biodiversity of the Portuguese Oligocene, is based on a small collection deposited in the Stratigraphic collection of the Museu Geológico (MG)
Variação composicional dos solos do Cabo Mondego (Portugal): novos dados de suporte para estudos ambientais
No full textABSTRACT: This study aims to determine physicochemical parameters of soils from Cabo Mondego area (Central Portugal), allowing the establishment of the natural background to serve as a reference to identify variations resulting from industrial activities. Forty-three surface soil samples were collected near the deactivated industrial complex and another seven in more distant areas. The soils present a predominantly sandy texture and pH values in the alkaline range, which reflects the geological signature. The soils electrical conductivity of five samples present values above the Portuguese reference value for contaminated soils. The anomalous values measured in a sample (CM-S3) were related to the presence of coal mining wastes located nearby. From the determined elements, the most abundant is Ca reflecting the limestone rocks composition, and a lithological control was identified in the spatial analysis, where higher concentrations of Fe and Al are coincident to the spatial occurrence of carbonaceous complex and limestones.RESUMO: Este estudo tem como objetivo determinar parâmetros físico-químicos dos solos da área do Cabo Mondego (Centro de Portugal), permitindo o estabelecimento do fundo natural para servir como referência para identificação de variações composicionais resultantes de atividades industriais. Quarenta e três amostras de solos superficiais foram coletadas próximas ao complexo industrial desativado e outras sete em áreas mais distantes. Os solos apresentam predominantemente textura arenosa e valores de pH na faixa alcalina, o que reflete a assinatura geológica local. Os dados de condutividade elétrica do solo mostram que cinco amostras apresentam valores superiores aos de referência para solos contaminados em Portugal. Os valores anómalos medidos na amostra CM-S3 estão relacionados com resíduos de mineração de carvão localizados nas proximidades. Dos elementos analisados, o mais abundante é o Ca, refletindo a composição de rochas calcárias, e foi identificado um controle litológico na análise espacial, em que amostras com maiores concentrações de Fe and Al estão localizadas na área de ocorrência do complexo carbonoso e calcários
Radiation safety assessment: Exploration of mineral deposits (mines) versus mineral masses (quarries)
No full textRESUMO: No âmbito do regime jurídico da proteção radiológica, a indústria extrativa deve realizar uma avaliação de segurança radiológica (ASR) para determinar se a atividade origina um incremento da exposição dos trabalhadores ou do público às radiações ionizantes que não possa ser ignorado do ponto de vista da proteção radiológica. A exploração de depósitos minerais (minas) exige maior intervenção humana do que a exploração de massas minerais (pedreiras) devido à necessidade de extração dos metais ou minerais de interesse económico. As atividades industriais de beneficiação do minério alteram as condições ambientais e consequentemente as propriedades físico-químicas dos radionuclídeos, podendo levar à sua mobilização seletiva e a um enriquecimento da concentração de radionuclídeos nos produtos ou resíduos gerados. No caso das pedreiras, em que a massa mineral é usada na forma em que é extraída, não ocorre esse enriquecimento e o risco radiológico é menor. Por esse motivo, foi adotada uma abordagem graduada da ASR nas pedreiras que presume a apresentação à APA de uma ASR simplificada e, apenas nos casos em o risco radiológico associado o justifica, será solicitada uma ASR completa.ABSTRACT: Under the legal framework for radiation protection, the extractive industry must carry out a radiological safety assessment (RSA) to evaluate whether the activity leads to an increase in the exposure of workers or the public to ionizing radiation that cannot be ignored from the radiological protection point of view. The exploitation of mineral deposits (mines) requires a higher level of human intervention than quarrying due to the need to extract metals or minerals of economic interest. The industrial activities of ore processing change the environmental conditions and consequently the physicochemical properties of radionuclides, and may lead to their selective mobilization and an enrichment of the radionuclide concentration in the generated products or residues. In the case of quarrying, where the mineral mass is used in the form in which it is extracted, there is no such enrichment and the radiological risk is lower. For this reason, a graded approach to RSA for quarries has been adopted, with a simplified RSA being presented to APA and, only in cases where the associated radiological risk justifies it, will a full RSA be requested
The use of infrasound in seismovolcanic monitoring. State of the art in the Azores archipelago
No full textRESUMO: As primeiras referências a registos de infrassons associados a atividade vulcânica explosiva, remontam à erupção do vulcão Krakatoa em 1883. Os trabalhos pioneiros de investigação em infrassons foram desenvolvidos nas décadas de 60 a 80 do século XX. No entanto, foi com a assinatura do Tratado de Proibição Total de Ensaios Nucleares (CTBT) que os estudos em infrassons se começaram a destacar. A instalação da estação de infrassons IS42 na ilha Graciosa, no âmbito do regime de verificação do CTBT, permitiu ao IVAR iniciar a aplicação desta técnica de investigação com vista à sua integração nas suas redes de monitorização. Várias deteções de atividades eruptivas explosivas remotas (a milhares de quilómetros de distância) pela estação IS42 têm evidenciado bons resultados. Por outro lado, a monitorização da crise sismovulcânica de 2022 na ilha de São Jorge, com a instalação do array portátil de infrassons SJ1 em conjunto com a estação IS42, permitiu-nos integrar os seus resultados nos esforços de monitorização do IVAR e do CIVISA.ABSTRACT: The first references to infrasound records associated with explosive volcanic activity date back to the 1883 Krakatoa volcano eruption. Pioneer research works on infrasound associated with important volcanic eruptions were developed in the 60s to 80s of the 20th Century. However, it was with the signing of the Comprehensive Nuclear-Test-Ban Treaty (CTBT) that infrasound studies have experienced a major development. The installation of the IS42 infrasound station on Graciosa Island, under the CTBT verification regime, allowed IVAR to start applying this research
technique towards its integration in its monitoring networks. The detection of remote explosive eruptive activity (thousands of kilometres away) by IS42 station gave us good results. Moreover, the monitoring of the 2022 seismovolcanic crisis on São Jorge Island, with the installation of the SJ1 infrasound mobile array in conjunction with the IS42 station, has allowed us to integrate its results in the IVAR and CIVISA monitoring efforts
Comparison of the corrosion of ferritic and austenitic stainless steel (AISI 430 and AISI 316L) with LiNaK carbonate salts for thermal energy storage in CSP/CST applications
No full textABSTRACT: This study focuses on the corrosion rates and mechanisms of two stainless steels, austenitic AISI 316L and ferritic AISI 430, in contact with a eutectic mixture of LiNaK carbonates in long-term tests at 650 degrees C. The selection of these two stainless steels was based on their differences, both in their intrinsic characteristics and in the cost associated with each one. The research also underscores the importance of optimizing the descaling methods used to evaluate the corrosion rate. Corrosion rates were measured gravimetrically according to ISO 17245:2015, revealing an asymptotic behavior for both steels, with AISI 430 with a corrosion rate of 237 f 21 mu m and AISI 316L of 151 f 13 mu m after 2000 h of testing. Corrosion mechanisms were analyzed using SEM/EDS, GDOES, and XRD techniques, which identified well-defined oxide layers with varying compositions. Given the observed corrosion mechanisms and its lower cost, AISI 430 steel seems to have great applicability in CSP/CST plants, provided it is paired with an appropriate protective coating
Pre-Mesoproterozoic crustal framework and Mesoproterozoic evolution of the SW Angolan Shield: structural, geochemical, and isotopic insights from the Kunene Complex and surrounding basement
No full textABSTRACT: The southwestern Angolan Shield hosts the Earth's largest Mesoproterozoic massif-type anorthosite complex (up to 53,500 km(2)), the Kunene Complex (KC). This complex is the result of a long-lived (similar to 200 Ma) episodic emplacement of coalescent magmatic pulses. The recent acquisition of multidisciplinary data during the PLANAGEO project has significantly enhanced our understanding of the Precambrian crustal framework from the southwestern Angolan Shield. Combined multi-isotope, structural and geophysical data reveals distinctive crustal zones in the southwestern Angolan Shield that clearly influenced KC's emplacement within a back-arc setting. The spatio-temporal arrangement of KC pulses suggests westwards magma migration within a complex contractional regime involving large strike-slip systems. A long-lasting and extensive accretionary orogen was responsible for the tectono-thermal activity recorded during most of the Mesoproterozoic. Crustal thinning and partial melting of isotopically heterogeneous lower-crustal sources through mantle upwelling promoted the episodic felsic magmatism contemporaneous with the KC. Crustal contamination processes are evident in gabbroanorthosites, indicating mantle metasomatism and interaction with wall-rocks and granite melts during ascent, upwelled by lateral-driven forces. Deposition of extensive metasedimentary sequences (<1.26 Ga) covering the KC, along with 1.23-1.07 Ga sublithospheric and mantle-derived magmatism, indicate a shift from a compressional to an extensional regime during late-Mesoproterozoic times. Regional correlations with other Mesoproterozoic units in African and Brazilian counterparts suggest a shared geological evolution, despite potential differences in tectonic setting. These findings supports a refined geological model for the Mesoproterozoic evolution of the southwestern part of the Congo Craton