Geologia e Cartografia Geológica - GCG
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- 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.
- Evidências de alterações ambientais abruptas na transição Pérmico-Triásico na Bacia Carbonífera de N'Condédzi (Moçambique) [Resumo]Publication . Fernandes, Paulo; Pereira, Zélia; Vennemann, Torsten; Silva Mendes, Márcia Cristina; Jorge, Raul C. G. Santos; Lopes, Gilda; Albardeiro, Luís; Font, Eric; Adatte, T.; Marques, J.RESUMO: O limite Pérmico-Triásico (LPT) marca a crise biótica mais severa do Fanerozóico, associada a profundas perturbações ambientais e climáticas ligadas à Extinção do Pérmico-Triásico. Apresentamos os resultados de uma investigação multidisciplinar de alta resolução das alterações ambientais terrestres ao longo do LPT na Bacia Carbonífera de N’Condédzi, em Moçambique. Os dados obtidos do estudo da sondagem CIMT-014 integram palinostratigrafia, palinofácies, isótopos estáveis de carbono (δ¹³Corg) e carbono orgânico total (COT) para restringir a cronologia e a natureza das perturbações do ecossistema. Os depósitos do Pérmico Superior (Formação Matinde) registam ambientes de planície aluvial ricos em matéria orgânica e com presença de carvão, dominados por vegetação glossopterídea em condições climáticas húmidas. Estes depósitos são abruptamente sobrepostos por camadas de conglomerados e por estratos pobres em matéria orgânica da Formação Cádzi do Triássico Inferior, o que reflete uma mudança para sistemas fluviais de alta energia em condições áridas. Os dados palinológicos documentam uma transição rápida de uma flora diversificada, dominada por Glossopteris, para associações de baixa diversidade, dominadas por esporos, características de ecossistemas sob pressão ambiental. O registo de δ¹³Corg mostra um declínio gradual durante o Pérmico Superior, seguido de uma excursão negativa significativa (~5,4‰) no início do Triássico, que atinge um mínimo de −30,4‰. Esta excursão coincidiu com uma queda acentuada do COT e com uma grande alteração da flora, o que indica uma forte ligação entre a perturbação do ciclo do carbono exógeno e o colapso do ecossistema terrestre. O sinal isotópico indica uma entrada substancial de carbono enriquecido em ¹²C no ciclo do carbono exógeno, o que é consistente com as emissões vulcânicas e com a desgaseificação termogénica de sedimentos (argilitos, evaporitos e carbonatos) associada às Traps Siberianas. A não coincidência estratigráfica entre o limite Pérmico-Triásico (PTB), definido palinologicamente, e a excursão negativa do δ¹³Corg indica respostas terrestres assíncronas e/ou controlos deposicionais locais. Valores persistentemente baixos de δ¹³Corg e o empobrecimento palinológico no Triásico Inferior indicam um stress ambiental prolongado e uma recuperação lenta do ecossistema. Este estudo fornece novas perspetivas sobre a sensibilidade do ecossistema terrestre e a dinâmica do ciclo do carbono durante o LPT no Gondwana, enfatizando a importância combinada dos mecanismos de forçamento globais e regionais.
- 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.
- Geocronologia U-Pb de zircões detríticos e proveniência sedimentar nas regiõescarboníferas de Moatize e N’Condédzi (Bacia Karoo do Zambeze, Moçambique) [Resumo]Publication . Fernandes, Paulo; Jorge, Raul C. G. Santos; Albardeiro, Luís; Chew, David; Drakou, Foteini; Pereira, Zélia; Marques, JoséRESUMO: A geocronologia U-Pb de zircões detríticos das regiões carboníferas de Moatize e N’Condédzi, na Bacia Karoo do Zambeze (Moçambique), fornece informações importantes sobre a proveniência sedimentar e a evolução da bacia. A sucessão estratigráfica, com idades entre o Roadiano (Pérmico médio) e o Carniano (Triássico superior), é constituída por arenitos, argilitos e camadas de carvão, depositados em ambientes aluvionais-lacustres em bacias de rift continental, com espessura superior a 2 km. Os arenitos pérmicos da região de Moatize apresentam três populações de zircões detríticos (1150–950 Ma, 900–780 Ma e 650–490 Ma), enquanto os de N’Condédzi mostram apenas uma população (1150–950 Ma). Durante o Pérmico, a proveniência dos sedimentos de N’Condédzi esteve associada ao Terreno Tete-Chipata e ao Complexo Malawi. Em Moatize, os depósitos iniciais de ambiente deltaico lacustre (Roadiano–Wordiano) indicam uma proveniência dominante do Cinturão Zambeze (900–780 Ma), com contribuições secundárias do Bloco Nampula (1150–950 Ma e 650–490 Ma). A evolução de um ambiente deltaico lacustre para um sistema aluvionar em Moatize é atribuída a um evento tectónico significativo, que originou sistemas fluviais com elevada carga sedimentar e canais entrançados. Os arenitos desses canais mantêm as três populações de zircões detríticos, refletindo proveniência combinada do Cinturão Zambeze e do Bloco Nampula. Em depósitos mais recentes, associados a canais em meandros, observa-se uma diminuição da contribuição do Cinturão Zambeze, sugerindo uma mudança de proveniência dominante para o Bloco Nampula, possivelmente controlada pela tectónica. A ausência de populações de zircões de 900–780 Ma e de 650–490 Ma nos arenitos pérmicos de N’Condédzi indica que as duas regiões não estavam interligadas durante o Pérmico. É provável que um horst intra-rift, representado pela Suite Gabro-Anortosítica de Tete (Mesoproterozoico), tenha actuado como barreira paleogeográfica entre as duas regiões. No Triássico Inferior, os arenitos de N’Condédzi apresentam uma população dominante de zircões detríticos de 1150–950 Ma, o que confirma a proveniência do Terreno Tete-Chipata e do Complexo Malawi. Uma população minoritária (650–490 Ma) está associada a condições mais áridas, coincidentes com a transição Pérmico-Triássico, e à expansão da bacia de drenagem. Já no Triássico Superior, a predominância da população de 1150–950 Ma indica um regresso às condições de proveniência semelhantes às do Pérmico médio e superior, reflectindo, uma vez mais, a interacção entre a actividade tectónica e a sedimentação.
- 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.
- Terrestrial environmental change across the Permian-Triassic boundary in the Karoo Zambezi Basin, Mozambique: Integrating palynological, sedimentological and carbon isotope evidencePublication . Fernandes, Paulo; Pereira, Zélia; Spangenberg, J. E.; Silva Mendes, Márcia Cristina; Lopes, Gilda; Jorge, Raul C. G. Santos; Albardeiro, Luís; Font, Eric; Adatte, T.; Vennemann, T.; Marques, J.ABSTRACT: The Permian-Triassic boundary (PTB; ca. 252 Ma) marks the most severe biotic crisis in Earth history, yet high-resolution terrestrial records from southeastern Gondwana, outside the Main Karoo Basin of South Africa, remain scarce. We present a multidisciplinary investigation of borehole CIMT-014 from the N'Cond & eacute;dzi Coalfield, Mozambique, which preserves a near-continuous continental succession spanning the PTB within the Karoo Zambezi Basin. Sedimentological, palynological, palynofacies, total organic carbon (TOC), and organic carbon isotope (delta(13)Corg) analyses were integrated to reconstruct environmental, ecological, and carbon-cycle changes across the transition. The uppermost Permian Matinde Formation comprises organic-rich floodplain mudstones, siltstones, and thin coal seams deposited under warm, humid conditions and dominated by Glossopteris-associated gymnosperm floras. Crossing the PTB, these deposits are abruptly replaced by conglomeratic, lacustrine, and fluvial sediments of the C & aacute;dzi Formation. Palynological data document a marked decline of glossopterid and other gymnosperm pollen, followed by a short-lived increase in opportunistic lycophyte and fern spores. Concurrently, palynofacies shift from assemblages rich in non-opaque phytoclasts to assemblages dominated by opaque phytoclasts, while TOC values decline from >40 wt% in coal-bearing intervals to <0.2 wt% in the earliest Triassic succession. A pronounced negative delta(13)Corg excursion of approximately 5.4 parts per thousand occurs across the boundary interval, with values decreasing from -25.0 parts per thousand to a minimum of -30.4 parts per thousand. The magnitude, stratigraphic coherence, and association with floral turnover, cessation of peat formation, and fluvial reorganisation indicate that the isotopic carbon excursion records a major perturbation of the global carbon cycle rather than local diagenetic effects. The isotopic signal is consistent with widespread carbon-cycle disruption linked to Siberian Traps magmatism and associated greenhouse-gas emissions. Our results demonstrate that terrestrial ecosystems in southeastern Gondwana experienced profound ecological and environmental disruption during the end-Permian crisis and establish the Karoo Zambezi Basin of Mozambique as a key archive for correlating continental records of the PTB in Gondwana.
- Using ESA NoR high-resolution data to support coastal management: the Baleal– Óbidos lagoon case study [Resumo]Publication . Nave, Silvia; Gonçalves, Pedro; Albardeiro, Luís; Mesquita Soares, SofiaABSTRACT: The study of coastal cliffs is essential for territorial management, public safety, and environmental preservation, given their inherently dynamic and geomechanically unstable nature. The significant rise in coastal area occupation requires the development of strategically focused methodologies that facilitate efficient and rapid monitoring of coastlines featuring sea cliffs, where mass movements are more likely to occur. Monitoring these landforms requires decimetre-scale spatial resolution to capture geomorphological changes such as clifftop retreat, block detachment, and the development of structural discontinuities. This study examines a small section from a cliffed coastline bordered by a continuous sandy beach located on the western coast of Portugal, between Baleal and the Óbidos Lagoon, a gently curved stretch of coast with approximately northeast to southwest orientation. The sea cliffs, reaching up to 50 meters above sea level, with varying slopes and heights, are broken up by two fluvial valleys, forming a local beach-dune system in those areas. The multi-sensor analysis carried out in this analysis enabled the precise identification of clifftop retreat and structurally significant discontinuities along the Praia d'El Rey sector. Multi- temporal differencing of Vexcel Elevate DTMs (2020–2024) revealed spatially coherent zones of material loss along the cliff face and beach interface (Figure 1). However, these results remain preliminary: uncertainty persists due to (i) tidal stage differences between acquisitions affecting intertidal elevations, (ii) co-registration offsets between epochs, and (iii) unvalidated vertical accuracy of the DTM products at this site. This study highlights the critical role of initiatives like the ESA Network of Resources, supported by the European Union Space Programme, in advancing efficient and timely monitoring of sea- cliff morphology. By reducing barriers to the use of commercial ultra-high-resolution satellite data, these programmes enable high-precision coastal research. In the absence of such institutional support, sub-metre imagery would remain largely inaccessible to public research institutions, underscoring the strategic significance of European Earth Observation programmes in supporting evidence-based coastal hazard management.