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Percorrer GEOCIÊNCIAS por Objetivos de Desenvolvimento Sustentável (ODS) "13:Ação Climática"
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- Depositional environment and redox conditions of the Moncorvo Ironstone: Unveiling the evolution of ironstones under Rheic Ocean influencePublication . Urbano, Emilio Evo Magro Correa; Preto Gomes, Maria Elisa; Pinto de Meireles, Carlos Augusto; Brandão, Paulo Roberto Gomes; Hippertt, Joa Pedro T.M.; Scholz, Ricardo; Lana, CristianoABSTRACT: Ironstones, as key archives of past marine environments, provide invaluable insights into Paleozoic history. Their mineralogy may reflect the physical-chemical conditions of the environment and the nature of available sediments. This study focuses on the Moncorvo Ironstone, a Lower-Middle Ordovician deposit formed during the opening of the Rheic Ocean. Here, we use an integrated approach combining sedimentology, petrology, and geochemistry to constrain the depositional settings and the redox landscape associated with the ironstone deposition. The Moncorvo Ironstone present some unusual characteristics, such as the lack of ooids, an uncommon mineralogy, and a stratigraphic thickness that can reach over >45 m, a remarkable feature for an ironstone. Our investigation reveals that this iron-rich sequence is distributed in two distinct marine environments: an inner shelf and a middle to distal shelf. Each environment has a unique mineral assemblage. Despite the influence of metamorphism and deformation, evidence suggests that much of the mineralogy and texture of this deposit still preserve characteristics of the original sediments. Finally, our findings, alongside a careful assessment of the mineralogy of other ironstones of similar age, suggest a strong stratification of the Rheic Ocean throughout the Early and Middle Ordovician.
- Empowering Citizen Science Through Stakeholder EngagementPublication . Correia, Vítor; Romão, José; Tyrologou, Pavlos; Gomes, Rui Carrilho; Correia, Vítor; Bodó, BalazsABSTRACT: The chapter examines how citizen science projects, particularly in geohazard monitoring, can be strengthened through systematic stakeholder engagement. Using the AGEO project as a case study, with five established Citizen Observatories across Europe, it details how stakeholders were identified, classified, and engaged across political, economic, knowledge and socio-cultural systems. The paper identifies five crucial factors for successful engagement: relevance, accessibility, trust, recognition/incentives, and sustainability. It concludes that citizen science, supported by technological advances and proper stakeholder engagement, can make significant contributions to disaster preparedness and risk reduction, particularly in the context of climate change, by fostering collaboration between experts and communities.
- Estudos de Geologia e Energia via deteção remota no LNEG [Comunicação oral]Publication . Quental, Lídia; Simões, Teresa; Gonçalves, Pedro; Couto, António; Costa, Paula Silva; Nave, Silvia; Carvalho, João; de Oliveira, Daniel Pipa Soares; Simoes, Sofia; Patinha, Pedro; Dias, Ruben; Justino, Paulo Alexandre
- Insights into rare earth elements and other critical raw materials from Castelo Branco massif alluvial deposits (Portugal)Publication . Salgueiro, Rute; Silva, Teresa; Martín-Méndez, I.; de Oliveira, Daniel Pipa Soares; Batista, Maria Joao; Inverno, CarlosABSTRACT: Actual and future demands for critical raw materials and strategic raw materials (CRM/SRM) justify the global search for their potential sources and the exploration approaches to reach them. This study discloses the characterization of rare earth elements (REE) and other CRM-bearing alluvial heavy minerals samples sourced from the late- to post-tectonic Variscan Castelo Branco Massif (Portugal). It also contributes to an understanding of REE, Th, and U anomalies from local and correspondent stream sediments identified in past geochemical surveys. The alluvial samples were subjected to semiquantitative analysis of their minerals under a binocular microscope and to chemical analysis through portable X-ray fluorescence. A varied mineralogical association and a geochemical fingerprint compatible with their main granitic source was identified, revealing several minerals that carry CRM, in which REE and titanium minerals stood out. The titanium minerals have the higher average abundance (54%), being ilmenite-dominant (50%), as supported by the relatively higher Ti content of these samples (up to 28.88%). The REE minerals occur as accessories and have a summing average of 12%, in which monazite is the most abundant (4.97%). Geochemical data support alluvial monazite as the mineral with the highest REE and Th concentrations, as described in the literature on its granitic source. In addition, the magnetic fraction of samples (∼85%) that includes monazite and xenotime presents LREE anomalous contents (up to 4,557 mg/kg) in relation to their granitic source, NASC, and even to ΣREE anomalous values revealed by local stream sediments. The Th (up to 1,969 mg/kg) and U (up to 244 mg/kg) contents follow the same trend. Nevertheless, the nonmagnetic mineral fraction that includes apatite and zircon reaches higher U contents (up to 448 mg/kg). This study indicates that the SRM Ti (ilmenite) and LREE (monazite) have the potential to form placer deposits sourced from Castelo Branco granitic rocks in a wider area, which is supported by the regional Ti placers exploited in the past. The occurrence of other accessory elements/minerals with industrial applicability associated with those placers may also represent future added value.
- Ranked Mappable Criteria for Magmatic Units: Systematization of the Ossa-Morena Zone Rift-Related Alkaline BodiesPublication . Roseiro, José; Moreira, Noel; de Oliveira, Daniel Pipa Soares; Silva, Marcelo; Eguiluz, Luis; Nogueira, PedroABSTRACT: The Ossa-Morena Zone (SW Iberian Massif) hosts the largest set of Cambro-Ordovician alkaline magmatic plutons related to the Palaeozoic rifting of the northern Gondwana margin so far described. An organized framework for their classification at different scales is proposed through data-driven ranks based on their distinctive petrological features relative to other rift-related magmatic rocks found throughout western Europe. The classification method aims to enhance geological mapping at different scales, regional- and continental-scale correlations, and, as such, facilitate the petrogenetic interpretation of this magmatism. The hierarchical scheme, from highest to lowest rank, is as follows: rank-1 (supersuite) assembles rocks that have distinctive characteristics from other magmatic units emplaced in the same magmatic event; rank-2 (suite) categorizes the units based on their major textural features, indicating if the body is plutonic, sub-volcanic, or a strongly deformed magmatic-derived unit; rank-3 (subsuite) clusters according to their spatial arrangement (magmatic centres) or association to larger structures (e.g., shear zones or alignments); rank-4, the fundamental mapping unit, characterizes the lithotype (alkaline granite, alkaline gabbro, syenite, albitite, etc.) by considering higher ranks (alkalinity and textural aspects); rank-5 characterizes the geometry of individual plutons (with several intrusions) or swarms; rank-6 (smallest mappable unit) corresponds to each intrusion or individual body from a swarm. Although this classification scheme is currently presented solely for the Ossa-Morena Zone, the scheme can be easily extended to incorporate other co-magmatic alkaline bodies, such as those in the NW Iberian allochthonous units or other peri-Gondwanan zones or massifs, in order to facilitate regional correlations of the rift-related magmatism.
- SedDARE-IB: an open-access repository of sediment data for the Iberian Peninsula and its continental marginsPublication . Torne, Montserrat; Alves, Tiago M.; Jimenez-Munt, Ivone; Carvalho, João; Ayala, Conxi; Ramalho, Elsa; Gomez-Garcia, Angela Maria; Matias, Hugo; Heida, Hanneke; Balaguera, Abraham; Garcia-Lobon, Jose Luis; Verges, JaumeABSTRACT: Sediments provide valuable information for geologists and geophysicists whenever they strive to understand, and reproduce, the geological evolution, lithology, rock properties, seismic response, and geohazards of a region. The analysis of sedimentary sequences is thus useful for the interpretation of depositional environments, sea-level change, climate change, and recognition of the sediments' source areas. By integrating sedimentary data into geophysical modeling, such interpretations are improved in terms of their accuracy and reliability. To further help our understanding of the Iberian Peninsula's geological evolution, geological resources, and geohazards, this work presents to the scientific community the SedDARE-IB data repository. This repository includes available data on the depth to the Base of the Cenozoic and Top of the Paleozoic stratigraphic markers for the Iberian Peninsula, the surrounding West Iberian Atlantic Margin and Western Mediterranean Neogene basins, or the acoustic basement as interpreted for the Valencia Trough and Alboran Mediterranean basins. As an example of the broad applicability of the data included in SedDARE-IB, we investigate how sediment thickness affects the depth to the 150 degrees C isotherm in specific basins, as commonly used in geothermal exploration. The calculated trend suggests that, given constant measured surface heat flow and thermal conductivity, the 150 degrees C isotherm becomes shallower as the sediment thickness increases, until a critical threshold value is reached for the latter. The SedDARE-IB database has been compiled thanks to a Portuguese-Spanish collaboration promoting open data exchange among institutions and research groups. SedDARE-IB is freely available at 10.20350/digitalCSIC/16277 (Torne et al., 2024), bringing opportunities to the scientific, industrial, and educational communities for diverse applications.
- Use of mining wastes for high-tech thermoelectric applications : The case of START project in Iberian Pyrite Belt [Resumo]Publication . Morais, Igor; de Oliveira, Daniel Pipa Soares; Silva, Teresa; Albardeiro, Luís; Salgueiro, Rute; Neves, FilipeABSTRACT: Europe aims to become the first climate neutral continent by 2050, which means rapidly implementing a green transition to which the European Union (EU) is strongly committed through the European Green Deal. This green transition leverages unprecedented pressure on the intensive use of mineral resources. In this context the START project “Sustainable Energy Harvesting Systems Based on Innovative Mine Waste Recycling” emerged with the objective to use mining waste as a source of raw materials for the development of advanced energy conversion devices. Thermoelectric materials (TE) are functional materials that can directly convert thermal energy into electricity.