GEOCIÊNCIAS
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Percorrer GEOCIÊNCIAS por Domínios Científicos e Tecnológicos (FOS) "Ciências Naturais::Outras Ciências Naturais"
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- Chemical and Mineralogical Characterization ofWaste from Abandoned Copper and Manganese Mines in the Iberian Pyrite Belt, Portugal: A First Step Towards the Waste-to-Value Recycling ProcessPublication . de Oliveira, Daniel Pipa Soares; Silva, Teresa; Morais, Igor; Fernandes, JoãoABSTRACT: This study examines the chemical and mineralogical composition of waste materials from abandoned copper and manganese mines in the Iberian Pyrite Belt, Portugal, as a first step toward their potential recycling for critical and strategic raw materials (CRM and SRM). Using portable X-ray fluorescence (pXRF) and other analytical techniques, this research highlights the presence of valuable elements, including copper, manganese, and rare earth elements, in concentrations significantly above their crustal abundance. The findings underscore the dual potential of these wastes: as sources of secondary raw materials and for mitigating environmental hazards such as acid mine drainage (AMD). Recovered materials include chalcopyrite, pyrolusite, and rhodochrosite, with critical elements like cobalt, lithium, and tungsten identified. pXRF proved to be a reliable, cost effective tool for rapid field and laboratory analyses, demonstrating high precision and good correlation with standard laboratory methods. The study emphasizes the importance of characterizing historical mining waste to support a circular economy, reduce reliance on foreign material imports, and address environmental challenges. This approach aligns with the European Union’s Critical Raw Materials Act, promoting sustainable resource use and the recovery of strategic resources from historical mining sites.
- 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.
- Follow that blade!- Petroarchaeological proxies as indicators of human mobility during the Copper age of the SW of the Iberian Peninsula: Vila Nova de Sao Pedro case study (Portugal)Publication . Jordão, Patrícia; Neves, César; Mesquita Soares, Sofia; Morgado-Rodríguez, Antonio; Diniz, Mariana; Arnaud, José M.ABSTRACT: Petroarchaeological proxies of blades are a powerful tool for the study of mobility in prehistoric populations to deliver more information on the network relationships of exchange, particularly during the Copper age. However, it is only recently that the first petroarchaeological studies have begun in the SW of the Iberian Peninsula, concerning Recent Prehistory. A sampling of blades from Vila Nova de Sao Pedro, one of the main fortified settlements in Portuguese Estremadura, was used for petrographic and geochemical study. Following the same protocol, geological samples of flint and also igneous rocks were analysed. Additionally, a techno-typological approach was combined in order to characterize the blades types in circulation. This preliminary study traced the diverse and complex dynamics of blade production, which involved the collection of the most readily available Rio Maior flint and the regionally selected Caxarias flint. There were no significant differences in knapping techniques for these two types of flint. The most distant oolitic varieties from Subbetic Cordillera (within 500 km) and the igneous rocks from the Iberian Piryte Belt (within 250 km), particularly for large blades, were not debitated at the site. Due to the high numbers of those types of materials at the site, Vila Nova de Sao Pedro most likely played a significant role in the complex mobility networks of large blades, establishing itself as an aggregating site and possibly a distributor of these artefacts to the Southwest of the Iberian Peninsula. Considering the proximity and the quality of Rio Maior flint sources but also to the amount of raw materials at the site sourced from a long distance, this study shows that mobility is more influenced by cultural motivations than by the availability or quality of raw materials.
- New Contributions to Mineralogical and Geochemical Knowledge of Old Preguiça Mine, Beja, PortugalPublication . Silva, Teresa; Morais, Igor; Mesquita Soares, Sofia; Rodrigues, Ivo; de Oliveira, Daniel Pipa Soares; Mirao, JoseABSTRACT: Abandoned mining areas provide valuable opportunities to investigate ore-forming processes, supergene mineral transformations, and the geochemical behaviour of metals. In this sense, the old Preguiça mine (Beja, Portugal), exploited for Fe–Zn–Pb, was studied providing new mineralogical and geochemical data aimed at improving the understanding of the secondary mineral assemblages of this deposit. A total of 70 samples collected from three accessible underground levels (first, second and third) and mine waste, complemented by 16 samples from a deeper level (fourth) previously collected, were analysed using X-ray diffraction (XRD), scanning electron microscopy (SEM), and a portable X-ray fluorescence (pXRF) equipment. Mineralogical phases are dominated by a wide range of secondary oxides, carbonates, arsenates, vanadates, silicates, phosphates and sulphates, but remnants of primary sulphides were also found. The following minerals can be emphasised: goethite, hematite, calcite, dolomite, descloizite, willemite, mimetite, cerussite, smithsonite and fraipontite. The presence of massicot in the Preguiça mine, is described for the first time. Bulk geochemical analyses show high concentrations of Fe, Ca, Zn and Pb, consistent with the observed mineralogy. The presence of vanadium- and arsenic-bearing minerals highlights the occurrence of critical raw materials, supporting the importance of reassessing other abandoned mining areas in the context of sustainable resource management and strategic raw-material planning.
- The palynology of the Upper Triassic-Lower Jurassic in the Algarve and Lusitanian basins, PortugalPublication . Vilas Boas, Margarida; Cirilli, Simonetta; Pereira, Zélia; Duarte, Luis; Fernandes, PauloABSTRACT: High-resolution palynological analyses from the Algarve and Lusitanian basins (Portugal) provide a refined biostratigraphical framework and palaeoenvironmental reconstruction for the Late Triassic-Early Jurassic transition. In the Algarve Basin, three new palynozones (AT, SC, and CP) characterise the Silves Group from the early Carnian to early Hettangian, documenting the first Iberian occurrence of Tulesporites briscoensis and precisely delineating the Triassic-Jurassic Boundary (TJB). In the Lusitanian Basin, three palynozones (CG, IK, and Pm) constrain the Conraria and Pereiros formations to the Norian-Hettangian, with the TJB located at the base of the Pereiros Formation. Palaeoenvironmental reconstructions reveal distinct basin-specific evolutions. The Algarve Basin records an early transition from fluvial (Silves Sandstones) to marginal-marine (lagoonal and pond) settings, evidenced by abundant upper Carnian algal elements and reworked Neoproterozoic algae. Conversely, the Lusitanian Basin reflects a Norian-Hettangian marginal-marine, river-dominated setting, with microforaminiferal linings at the base of the Pereiros Formation marking the earliest marine transgression in the Lusitanian Basin. Quantitatively, both basins show a persistent dominance of xerophytic taxa, indicating a shift toward warmer, seasonally dry conditions across the TJB. Malformed sporomorphs in both records suggest environmental stress potentially linked to Central Atlantic Magmatic Province (CAMP) activity. Comparative analysis reveals that sedimentation initiated earlier in the Algarve (early Carnian) than in the Lusitanian Basin (Norian), suggesting diachronous development during Pangaea breakup. The assemblages show strong affinities with the Onslow Microflora, highlighting the Portuguese margin as a key archive for western Tethyan floral and climatic evolution.