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Geologia colonial: o protagonismo do museu da Politécnica de Lisboa
Get PDFRESUMO: O Museu Mineralógico e Geológico instalado na antiga Escola Politécnica de Lisboa incorporou, desde finais do século XIX, centenas de amostras geológicas ultramarinas resultantes de colheitas dos delegados científicos e de ofertas de agentes da administração colonial. Estes materiais propiciaram, além de matéria de publicações científicas, a constituição de um importante repositório das “riquezas” do subsolo daqueles territórios, acessível aos investigadores e a outros interessados desde meados de 1936, quando foi aberta a “Sala do Império Colonial”. Este acervo e as relações privilegiadas com África e com o Ministério das Colónias (mais tarde Ministério do Ultramar), mantidas por docentes e investigadores, colocaram a “Politécnica” numa posição axial nos estudos de geologia das antigas colónias portuguesas, reforçada através de novas missões em África e na Índia, a partir dos anos de 1960. Apesar dos danos e perdas decorrentes do incêndio de 1978, o remanescente destas coleções, mineralógicas, paleontológicas e petrográficas, em curso de recuperação e inventariação, ainda hoje conserva o interesse, tanto como testemunho da geodiversidade
daqueles territórios, como do ponto de vista da história das geociências em Portugal. Ao revisitar e cruzar coleções, documentos de arquivo e publicações, o presente artigo identifica as motivações e os contextos de formação deste acervo colonial, elencando os seus principais atores.ABSTRACT: The Mineralogical and Geological Museum established in the former Polytechnic School of Lisbon, amassed since the late nineteenth century, hundreds of geological samples from overseas, sent by its scientific delegates or through agents of the colonial administration. These collections enabled the creation of an important repository for experts and people interested in the subject. In 1936, it opened to the public as the “Room of the Colonial Portuguese Empire”, whose purpose was to disseminate the knowledge over the mineral resources of those territories. The privileged relation between the museum and its collections, and Africa and the Ministry of Colonies (later on Overseas Ministry), maintained by the museum’s scientific staff, positioned the Polytechnic School into as a central actor in the studies of colonial geology. This position was enhanced with new scientific missions in Africa and India during the 1960s. Despite the damage and losses sustained during a fire at the museum in 1978, the remainder of these collections, currently under of recovery and inventory, still retains great interest as a testimony of the geodiversity of those territories, and of the history of Geosciences in Portugal. Revisiting and bringing together samples, archives and several publications, this paper aims to identify motivations and contexts of the colonial collections, listing its most important players.info:eu-repo/semantics/publishedVersio
Development of a georeferenced database as a tool to improve circular material flows in lignocellulosic waste valorization [Poster]
No full textPoster apresentado no Congresso 5th CIAB2024 (5º Congresso Ibérico de Biorrefinarias), realizado de 2-4 Outubro 2024 em Jáen, Espanha. Este poster ganhou o prémio de melhor poster deste congresso.ABSTRACT: The Frontsh1p project aims to accelerate the development and implementation of cross-sector circular value chains through the creation of a multi-level toolkit that includes georeferenced data. This will facilitate the identification of the different stakeholders, their levels of interaction, regional distribution, and communication pathways, as well as the planning of new circular material flows for by-products and waste streams. The region of Łódzkie in Poland was selected for the development of this toolkit to establish guidelines, methodologies and technologies, based on information at the regional economic level, that can be easily replicated in different regions across Europe
Palynology of the Albian–Turonian sediments from the Sumbe region, Kwanza Basin (Angola): Implications for paleoenvironment, paleoclimate, and paleogeography
Get PDFABSTRACT: Palynological investigations in the Sumbe region of the Kwanza Basin, Angola, have identified Albian to Turonian assemblages in four sections of the Quissonde Facies of the Mucanzo, Cabo Ledo, and Itombe formations. These studies aimed to determine their biostratigraphic ages and infer paleoenvironmental, paleoclimatic, and paleogeographic models. The presence of Odontochitina costata, Palaeohystrichophora infusorioides, and Xiphophoridium alatum cysts supports an upper Albian to lower Cenomanian age for the Mucanzo Formation. Litosphaeridium siphoniphorum cyst and the Elateroplicites africaensis pollen found In the Cabo Ledo Formation suggest a Cenomanian age, while Conosphaeridium striatoconum, Heterosphaeridium difficile, and Dinogymnium acuminatum supports a Turonian age for the lower part of the Itombe Formation. All samples predominantly contain fluorescent amorphous organic matter (AOM) derived from phytoplankton degradation, with increasing AOM in the uppermost units, indicating inner neritic marine deposition under dysoxic-anoxic conditions. During the Lower to mid-Cretaceous, the Gondwana breakup caused significant changes, with the palynological indicating a Tethyan affinity with some high-latitude taxa, suggesting a cosmopolitan distribution. The subtropical to tropical nature of the assemblages, along with high-latitude species, indicates a mid-Cretaceous water connection between the Central Atlantic and the South Atlantic oceans, extending to the Kwanza Basin.info:eu-repo/semantics/publishedVersio
Desenvolvimento de um fotobiorreator, em escala de bancada, com um novo sistema de recirculação para cultivo contínuo de microalgas - Patente nacional: PT 118320 (A)
No full textRESUMO: A presente invenção traduz-se no Desenvolvimento de um fotobiorreactor (FBR) para o crescimento fotoautotrófico contínuo de microalgas, num sistema quimiostato, à escala de bancada. este novo fbr integra um vaso de retenção, que garante a mistura das fases líquidas e gasosas e centraliza o controle dos parâmetros e condições de cultura, um fotocoletor, que maximiza a área iluminada e a fixação do carbono
através da fotossíntese, um desgaseificador, que previne a acumulação do oxigénio e assegura a recolha, e um novo conceito de recirculação que propicia uma cultura homogénea ao longo de todo o conjunto integrado funcionando como um único quimiostato. o protótipo do fbr desenvolvido está ilustrado no esquema da figura 1 (desenho sem considerar qualquer escala):(1) Recipiente de meio de cultura fresco; (2) Compressor de ar: g) fluxo de Ar (corrente gasosa contendo dióxido de carbono); (3) Bomba peristáltica; (4) Rotâmetro de precisão; (5) Bomba de recirculação da cultura autotrófica; (6) Câmara de gotejamento; (7) Conector em Y; (8) controlador de PH; (9) Banho termostatizado; (10) Vaso de retenção: A) Sensor de temperatura, B) Sonda de PH, C) Hélice de agitação magnética, D) Entrada da solução controladora de PH, E) Tubo borbulhador, F) Tubo nivelador; (11) Controlador de agitação; (12) Fotocoletor ¿ Série de colunas de bolhas (K); (13) Tomadas/ligações de acoplamento; (J) Cabeça lavadora de gases; (14) Desgaseificador: I) Tubo de descarga para colheita (para um recipiente de amostragem ou de colheita); (15) Condensador: H) Fluxo de ar de escape; (16) Analisador de gases.info:eu-repo/semantics/publishedVersio
Potential for hydrogen production associated to water and food in off-grid communities of Southern Africa
No full textABSTRACT: Solar energy is called to meet electricity demands for isolated, off-grid communities in Africa. However, solar electric energy is intermittent and can be stored, for a limited amount of time, in batteries, which are expensive and cause serious environmental impacts at the end of their lifetime. Conversion of the surplus electric energy to green hydrogen through water electrolysis and back to electricity, when needed, using electrolyser-fuel cells systems, is examined as a potential solution to meet the water-energy-food nexus in Southern Africa. In the framework of the Agrivoltaics concept, the main constrains, opportunities and parameters to consider its applicability are presented and discussed, in terms of its technical, economic, environmental and social impacts. In the second phase of this work the developing of a PEM electrolyser for connection to a solar PV power source and a fuel cell device, for a stand-alone application, is proposed, ensuring high reliability and energy conversion efficiencies, as well as adequate transient response and a competitive cost. It is intended as a low-carbon energy system, realising the potential for synergy in the Agrivoltaic concept, aligned with global and regional sustainability goals.info:eu-repo/semantics/publishedVersio
Magnetic modelling of the Kunene Complex (SW Angola)
No full textRESUMEN: 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).ABSTRACT: The Kunene Complex (KC) is an extensive Mesoproterozoic igneous massif composed of
anorthositic, gabbroic and contemporaneous acid rocks. Its outcrops extend over 18,000 km2 in a NNESSW
direction from SW Angola to NW Namibia. Aerogeophysical data obtained within the PLANAGEO project have been interpreted and modelled in 2.5D and 3D to investigate the concealed boundaries of the KC and to reconstruct the structure of the surface crust beneath the Kalahari cover. The modelling reveals a lobular geometry with an extension of almost three times the outcropping area, even larger than estimated by gravimetry (45,000 km2; Rey-Moral et al., 2022). The magnetic anomalies identified define individual bodies that formed several coalescent magmatic pulses during the Mesoproterozoic. Magnetic lineaments indicate large shear systems developed in various intrusive phases in a collisional arc context. Magnetic lineaments to the east suggest an emplacement associated with transtensive stages. To the W, with the most recent pulses, lineaments in a complex contractional regime are detected. Late NNW-SSE extensional structures involve mantle magmas and late-Mesoproterozoic basins (<1.33 Ga).N/
The National Geological Plan of Angola (PLANAGEO) [Resumo]
No full textRESUMEN: El Plan Nacional de Geología de Angola (PLANAGEO) ha sido uno de los proyectos geotemáticos
internacionales más importantes de las últimas décadas. El proyecto fue lanzado por Gobierno de la
República de Angola e implementado por el Instituto Geológico de Angola (IGEO), bajo la supervisión del Ministerio de Recursos Minerales, Petróleos y Gas (MIREMPET). Los principales objetivos de PLANAGEO fueron: a) profundizar en el conocimiento de los recursos geológicos; b) fomentar la diversificación de la economía; y, c) atraer inversión extranjera para promover el desarrollo socioeconómico del país. Tras licitación internacional, el IGEO otorgó al consorcio UTE PLANAGEO, formado por el Instituto Geológico y Minero de España (IGME), el Laboratorio Nacional de Energía y Geología de Portugal (LNEG) y la empresa Impulso Industrial Alternativo (IIA) la ejecución del proyecto en la zona sur de Angola, en un área aproximada de 480.000 km2. El contrato se firmó en octubre de 2013, por un importe de 115.312.500 USD, y los trabajos cartográficos fueron realizados entre 2014 y 2022. El proyecto incluyó el levantamiento aerogeofísico regional (mag/rad) y la cartografía geológica a escala 1:250.000 de todo el país, junto con otras cartografías de detalle a escala 1:100.000, y síntesis a escalas 1:500.000 y 1:1.000.000. Fueron realizadas campañas de prospección geoquímica a escala 1:250.000, y otros estudios específicos a escala 1:50.000, que incluyeron Mapas de Recursos Minerales Metálicos (CRMMA) y Mapas de Rocas y Minerales Industriales (CARMINA) en zonas de especial interés, así como estudios hidrogeológicos en la cuenca del Kalahari.ABSTRACT: The National Geological Plan of Angola (PLANAGEO) has been one of the most significant
international geothematic projects of recent decades. The project was launched by the Government of the
Republic of Angola and implemented by the Geological Survey of Angola (IGEO), under the supervision
of the Angolan Ministry of Mineral Resources, Petroleum and Gas (MIREMPET). The main objectives of
PLANAGEO were to deepen the knowledge of geological resources, foster the diversification of the economy, and attract foreign investment to promote the socio-economic development of the country. The UTE PLANAGEO consortium, consisting of the Geological Survey of Spain (IGME), the National Laboratory of Energy and Geology of Portugal (LNEG), and the company Impulso Industrial Alternativo (IIA), was awarded to execute the project in southern Angola, covering an area of ca. 480,000 km2. The contract, worth USD 115,312,500, was signed in October 2013 following an international call for tenders by IGEO. The work was carried out between July 2014 and the end of 2022. The project involved a regional aerogeophysical survey (mag/rad) and geological mapping at a scale of 1:250,000, along with other detailed mapping at a scale of 1:100,000 and synthesis maps at scales of 1:500,000 and 1:1,000,000. Geochemical campaigns were conducted at a scale of 1:250,000, and other specific studies were made at a scale of 1:50,000, including Metallic Minerals Maps (CRMMA) and Rock and Industrial Minerals Maps (CARMINA) in areas of special interest, as well as hydrogeological studies in the Kalahari basin.N/
Geochemical Map of Latin America and the Caribbean: Methods for implementation [Resumo]
No full textABSTRACT: The Geochemistry Experts Group of the Ibero-American Association of Geological Services is a
group of experts who exchange knowledge on exploration geochemistry and geochemical mapping as a result of the experience of each Geological Service. Currently, the group of experts has started to test the methodology for collecting information for the Geochemical Map of Latin America. The continental data unit used is the Global Terrestrial Network (GTN), following the recommendations for International Geochemical Mapping, but instead of 160x160 km, it will have a 40x40 km cell. The geochemical data will be collected in each cell, and an average value (median or geometric mean) will be determined.N/
Marine biomineralization for enhanced corrosion resistance: Insights from the ANR MICOATEC project [Poster]
No full textABSTRACT: 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.N/