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- Geochemical and Sr-Nd isotope constraints on the provenance of Permian deposits from Mozambique's Lower Karoo Zambezi BasinPublication . Jorge, Raul C. G. Santos; Fernandes, Paulo; Pereira, Zélia; Santos, José Francisco; Lopes, Gilda; Marques, JoãoABSTRACT: Whole-rock geochemistry and Sr-Nd isotopic compositions of Permian mudrocks from the Moatize and Matinde formations were analysed to constrain the sediment provenance, weathering history and palaeogeographic setting of the Moatize - Minjova Sub-Basin in the Karoo Zambezi Basin of Mozambique. The geochemical signatures of both formations suggest minimal effects of recycling and sorting, and point to rapid sediment deposition within an active tectonic setting. Trace element systematics and key provenance ratios (Th/Sc, La/Sc, Cr/Th, La-N/Sm-N,Sm- Eu/Eu & lowast;) indicate heterogeneous source areas dominated by felsic rocks with a minor mafic contribution. The mudrocks of the Moatize and Matinde formations exhibit similar isotopic signatures, with epsilon Nd (t) values of -9.32 +/- 0.74 and -7.99 +/- 1.10, and Nd T-DM model ages of 1.68 +/- 0.08 and 1.51 +/- 0.12 Ga, respectively. These isotopic signatures indicate that both formations were derived from mixed sources, including late Mesoproterozoic and Neoproterozoic rocks from southern Malawi, the Nampula Block (a subdomain of southernmost Malawi), the Guro Suite and the Macossa-Chimoio Nappe. Both Moatize and Matinde mudrocks exhibit high Chemical Index of Alteration (>85) and Chemical Index of Weathering (>90) values, along with low Index of Compositional Variability and low K/Cs ratios. The Al2O3-(CaO + Na2O)-K2O (A-CN-K) relationships indicate that the Moatize and Matinde mudrocks have not undergone post-depositional K-metasomatism. The data collectively indicate intense palaeoweathering conditions in the source areas. Furthermore, the weathering indices suggest warm and humid palaeoclimate during the deposition of the Moatize and Matinde formations. These formations were deposited in a confined continental basin between the Guadalupian (middle Permian) and the Lopingian (late Permian).
- Circular economy modelling for climate change mitigation: A review of empirical evidence and modelling approachesPublication . Zanon Zotin, Marianne; Fortes, Patricia; Corbier, Darius; Deetman, Sebastiaan; Edelenbosch, Oreane; van Engelenburg, Martijn; Hauenstein, Christian; Hertwich, Edgar; Jiang, Meng; von Köckritz, Luja; Magalar, Leticia; Pauliuk, Stefan; Straub, Lucas; Vélez-Henao, Johan; van Vuuren, DetlefABSTRACT: Circular economy (CE) measures can play a role in reducing greenhouse gas (GHG) emissions, especially in material- and energy-intensive sectors. Yet, their representation in GHG mitigation pathways is still not well captured in climate change mitigation models. To support modelling efforts towards better CE representation, two reviews were conducted: (1) the empirical evidence on the GHG mitigation potential of CE strategies across material supply and demand sectors and R-strategies, and (2) the current modelling approaches used to assess these strategies. Findings show that, while most studies focus on recycling, increasing attention is given to upstream strategies such as material substitution, design for reuse, and service-based business models. Important gaps remain, particularly around Refuse, Rethink, behavioural factors, rebound effects, as well as synergies and trade-offs with climate policy. Industrial ecology methods provide a detailed material flows representation but lack feedback mechanisms and economic dynamics. In contrast, GHG mitigation models offer broader system coverage but often simplify materials and CE dynamics. Better alignment between methods is needed, including shared definitions, improved data, and more collaboration across modelling communities. Strengthening the modelling of CE strategies can support policy-relevant assessments of CE’s contribution to achieving global climate goals.
- LNEG-H2PTMap: Calculadora Geoespacial do Custo de HidrogénioPublication . Portillo, Juan C. C.; Simoes, Sofia; Shabanifar, Soraya; Jordão, Luisa; Ricou, Maria; Costa, CatarinaRESUMO: O Laboratório Nacional de Energia e Geologia (LNEG) apresenta a primeira versão da ferramenta LNEG-H2PTMap, disponibilizada através do GeoPortal do LNEG. Esta calculadora geoespacial gratuita permite a estimativa rápida do Custo Nivelado do Hidrogénio (Levelised Cost of Hydrogen – LCOH) nos 278 municípios de Portugal Continental. A ferramenta integra os custos de produção de hidrogénio verde com as principais componentes da sua cadeia de valor aplicáveis aos setores dos transportes e da indústria, incluindo o armazenamento e a distribuição até ao utilizador final, permitindo a realização de análises flexíveis com base em parâmetros de referência atualizados e em condições locais. A ferramenta LNEG-H2PTMap foi desenvolvida no âmbito da iniciativa «Simulador Geoespacial de Custos de H₂», integrada na Agenda PRR M-ECO2. O presente relatório descreve a abordagem metodológica adotada para o desenvolvimento da ferramenta, incluindo o enquadramento metodológico do cálculo de custos, as fontes de dados, os pressupostos considerados e a sua implementação. Ao contrário de outras ferramentas para a avaliação de custos do hidrogénio, como a Calculadora LCOH do Observatório Europeu do Hidrogénio, que disponibilizam estimativas baseadas principalmente em dados à escala nacional, a ferramenta LNEG-H2PTMap permite a estimativa dos custos nivelados do hidrogénio à escala municipal em todo o território de Portugal Continental. Tanto quanto é do conhecimento dos autores, não existe atualmente nenhuma ferramenta de acesso público que disponibilize estimativas do custo nivelado do hidrogénio à escala municipal para a totalidade dos municípios de Portugal Continental. Esta resolução geográfica mais detalhada permite incorporar variações espaciais em fatores determinantes dos custos, incluindo a disponibilidade e o custo da eletricidade renovável, os requisitos de captação e tratamento de água e as distâncias de transporte de hidrogénio. Consequentemente, a ferramenta permite identificar diferenças de custo entre municípios que podem ficar ocultas quando se utilizam médias nacionais ou regionais, apoiando decisões mais informadas de investimento, planeamento e definição de políticas públicas. Ao captar estas variações espaciais à escala municipal, a ferramenta responde a uma necessidade concreta identificada por agentes da indústria, investidores, investigadores e decisores políticos de disporem de um instrumento de apoio à decisão prático, transparente e baseado em evidência. A ferramenta LNEG-H2PTMap facilita a identificação de localizações economicamente mais competitivas para a produção, armazenamento e distribuição de hidrogénio verde, apoiando o planeamento estratégico e contribuindo para uma implementação mais rápida, eficiente e direcionada da economia do hidrogénio em Portugal.
- LNEG-H2PTMap: Geospatial Hydrogen Cost CalculatorPublication . Portillo, Juan C. C.; Simoes, Sofia; Shabanifar, Soraya; Jordão, Luisa; Ricou, Maria; Costa, CatarinaABSTRACT: The National Laboratory for Energy and Geology (LNEG) presents the first version of the LNEG-H2PTMap Tool, available through the LNEG GeoPortal. This free geospatial calculator enables the rapid estimation of the Levelised Cost of Hydrogen (LCOH) across the 278 municipalities of mainland Portugal. The tool integrates the costs of green hydrogen production with the main components of its value chain applicable to the transport and industrial sectors, including storage and distribution to the end user, enabling flexible analyses based on up-to-date reference parameters and local conditions. The LNEG-H2PTMap Tool was developed under the “H₂ Cost Geospatial Simulator” initiative within the framework of the PRR Agenda M-ECO2. This report describes the methodological approach adopted for the development of the tool, including its cost calculation framework, data sources, assumptions, and implementation. Unlike other hydrogen cost assessment tools, such as the European Hydrogen Observatory's LCOH Calculator, which primarily provide estimates based on country-level datasets, the LNEG-H2PTMap Tool enables the estimation of levelised hydrogen costs at the municipal level throughout mainland Portugal. To the best of the authors' knowledge, no publicly available tool currently provides municipality-level levelised hydrogen cost estimates covering all municipalities of mainland Portugal. This finer geographical resolution enables the incorporation of spatial variations in key cost determinants, including renewable electricity availability and costs, water sourcing and treatment requirements, and hydrogen transportation distances. Consequently, the tool can reveal cost differences between municipalities that may be obscured when using national or regional averages, thereby supporting more informed investment, planning, and policy decisions. By capturing these spatial variations at the municipal scale, the tool addresses a concrete need identified by industry stakeholders, investors, researchers, and policymakers for a practical, transparent, and evidence-based decision-support instrument. The LNEG-H2PTMap Tool facilitates the identification of cost-competitive locations for green hydrogen production, storage, and distribution, thereby supporting strategic planning and contributing to the accelerated, efficient, and targeted deployment of the green hydrogen economy in Portugal.
- Intersectoral knowledge spaces of emerging technologies and innovation opportunities for established industrial sectorsPublication . Sousa, Cristina; Fontes, Margarida; Barbosa, Juliana PachecoABSTRACT: The paper investigates how the emergence of new sustainable technologies can induce innovation and change in the industrial sectors that contribute competences and resources to their development. For this, it develops and tests a framework to address knowledge recombination processes at the intersection of diverse sectoral knowledge bases. The paper maps the intersectoral knowledge space formed as part of the emergence of a new sustainable technology, marine renewable energy, and proposes that the position of a sector in that space – in terms of variety of connections and (un)relatedness between the connected sectors – is associated with differentiated opportunities for innovation and engagement in diversification into a new business. This research contributes to the literature on the industrial transformative effects of new technologies by uncovering some of the processes through which intersectoral knowledge relationships generate opportunities for knowledge (re)combination and innovation in firms from existing sectors. The results can inform policies that aim to combine sustainability and industrial development goals.
- A New Geochemistry Exploration Method to Identify Deep VMS-Type Deposits - Application to the Cu-Zn Neves-Corvo Deposit, Iberian Pyrite BeltPublication . Morais, Igor; Albardeiro, Luís; Rosado, Lúcia; Mirao, Jose; Xavier Matos, João Manuel; Batista, Maria Joao; Silva, Teresa; Barrulas, Pedro; de Oliveira, Daniel Pipa SoaresABSTRACT: Mineral exploration in the Iberian Pyrite Belt follows increasingly deeper targets. The present study introduces an innovative methodology for the detection and identification of blind metallic mineral deposits, in particular volcanogenic massive sulfides based on surface rock coatings. This approach follows the identification pathways of upward metal escape routes and metal distribution in rock fractures located in different anisotropic or isotropic planes above the Neves-Corvo VMS deposit ore lenses, using VP-SEM-EDS and XRD. Coatings are dominated by poorly crystalline to amorphous phases, with goethite and birnessite as the main Fe- and Mn-bearing minerals. Copper, zinc and lead are systematically enriched in coatings developed above or near the ore bodies, reflecting chalcopyrite, sphalerite and galena acidic leaching. Tin shows a restricted and heterogeneous distribution, while Ni and Co display no systematic relationship with the ore bodies. Barium and late Ba-Pb-(Zn) mineralization along fault zones record VMS mineralization. Lead isotopic coating signatures overlap those of IPB massive sulfide deposits, confirming a dominant VMS-derived contribution. Fe-Mn coatings were formed by precipitation from ascending meteoric fluids that leached metals from massive sulfides, their alteration halos, and surrounding lithologies, preserving the geochemical footprint of buried mineralization. This approach constitutes a new patented exploration tool.
- 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.