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- Palynological assemblages from Hongguleleng Formation of Western Junggar, Northwest China and their correlation with conodont zonationPublication . Shen, Zhen; Steemans, Philippe; Pereira, Zélia; Zong, Rui-Wen; Zhang, Xin-Song; Ma, Kun-Yuan; Gong, Yi-MingABSTRACT: The Upper Devonian Hongguleleng Formation is a significant stratigraphic unit near the Frasnian/Famennian and Devonian/Carboniferous boundaries of the Kazakhstan Paleoplate. However, its age is still under debate. A new palynostratigraphic analysis was conducted at the Gennaren section to provide a more accurate biostratigraphic assignment. In this study, we identified 43 species belonging to 26 spore genera, including those in open nomenclature. Despite the poor preservation of the palynofloras, the spore taxa were categorized into two assemblages. Assemblage I is established at the lower part of the lower member of the Hongguleleng Formation, containing Cornispora varicornata, cf. Auroraspora pseudocrista, and Cyrtospora cristifera. Assemblage II is from the upper part of the lower member of the Hongguleleng Formation, including Grandispora cornuta, Grandispora famennensis var. famennensis, Grandispora cf. famennensis var. minutus, Grandispora microseta, and Rugospora radiata. These assemblages are compared with the Western European DV Oppel Zone (lower-middle Famennian), and the GF to VCo Oppel zones. The assemblages are equivalent to the conodont crepida–rhomboidea and marginifera to Lower trachytera zones (middle-upper Famennian).
- RES.Trade: An Open-Access Simulator to Assess the Impact of Different Designs on Balancing Electricity MarketsPublication . Algarvio, Hugo; Couto, António; Estanqueiro, AnaABSTRACT: The 2050 global ambition for a carbon-neutral society is increasing the penetration of the most competitive variable renewable technologies, onshore wind and solar PV. These technologies are known for their near-zero marginal costs but highly variable time-dependent generation. Power systems with major penetrations of variable generation need high balancing flexibility to guarantee their stability by maintaining the equilibrium between demand and supply. This work presents the open-access Multi-agent Trading of Renewable Energy Sources (RES.Trade) system, which includes different market designs of the imbalance settlement and the secondary and tertiary reserves. A new imbalance settlement is also proposed in this work. The main features of RES.Trade are demonstrated using two case studies and projected 2030 scenarios: the first analysed four imbalance settlement mechanisms in Portugal, achieving a 43% reduction in penalties using the new method; the second case study assesses the impact of five procurement mechanisms of secondary power reserves in the Spanish power system, resulting in a cost reduction by 34% in the case of dynamic reserves.
- Detrital zircon U-Pb geochronology of the Moatize and N’Cond´edzi coalfields, Zambezi Karoo Basin of Mozambique: Implications for provenance, sediment dispersal and basin evolutionPublication . Fernandes, Paulo; Jorge, Raul CG Santos; Albardeiro, Luís; Chew, David; Drakou, Foteini; Pereira, Zélia; Marques, JoãoABSTRACT: Detrital zircon U-Pb geochronology of the Moatize and N'Condedzi coalfields in the Zambezi Karoo Basin of Mozambique provides key insights into the regional provenance, sediment dispersal pathways and basin evolution. Borehole cores from the two coalfields reveal a stratigraphy spanning the early Roadian (middle Permian) to the Carnian (Upper Triassic). The Permian sandstones of the Moatize Coalfield (MC) yield three detrital zircon populations, with ages ranging from 1150 to 950 Ma, 900-780 Ma and 650-490 Ma. In contrast, the Permian sandstones of the N'Condedzi Coalfield (NC) have only one population, which ranges from 1150 to 950 Ma. During the Permian, the provenance area for the NC was the Tete-Chipata Terrane and Malawi Complex (1150-950 Ma) to the north-northeast. In the MC, the detrital zircon populations of the early lake delta depositional setting (Roadian to Wordian) indicate a main provenance in the Zambezi Belt (900-780 Ma) located to the south of the MC, with minor sourcing from the Nampula Block (1150-950 Ma and 650-490 Ma) to the east. The transition from a lake delta to an alluvial depositional setting is attributed to a major tectonic event in the MC, which involved the formation of a braided channel belt. Sandstones from this braided channel belt yield three detrital zircons populations (650-490 Ma, 900-780 Ma and 1150-950 Ma), indicating provenance from both the Zambezi Belt and the Nampula Block. The overlying sandstones in the MC show only a minor population from the Zambezi Belt (900-780 Ma), implying a shift in provenance to the Nampula Block that was likely induced by tectonics. The absence of detrital zircon populations of 900-780 Ma and 650-490 in the Permian sandstones of NC implies that the two coalfields were not connected during the mid to late Permian. It is likely that an intra-rift horst (the Mesoproterozoic Gabbro-Anorthosite Tete Suite) separated the two coalfields. The Lower Triassic sandstones of the NC yield a main detrital zircon population indicating provenance from the TeteChipata Terrane and Malawi Complex (1150-950 Ma). A minor population at 650-490 Ma is linked to increased aridity at the Permian - Triassic boundary, which caused expansion of the watershed across the Tete-Chipata Terrane and the Malawi Complex. The Upper Triassic sandstones in the NC yield a 1150-950 Ma detrital zircon population, indicating provenance from the Tete-Chipata Terrane and Malawi Complex and a return to the source-to-sink conditions seen in the mid to late Permian.
- Technological innovations in decarbonisation strategies: a text-mining approach to technological readiness and potentialPublication . Costa, Paulo Moisés; Duarte, António; Tomé, Paulo; Bento, Nuno; Fontes, MargaridaABSTRACT: This study presents a novel, multifaceted approach to evaluating decarbonisation technologies by integrating advanced text-mining tools with comprehensive data analysis. The analysis of scientific documents (2011-2021) and mapping 368 technologies from the IEA's Energy Technology Perspectives identified 41 technology domains, including 20 with the highest relevance and occurrence. Domain readiness was assessed using mean Technology Readiness Levels (TRLs) and linked to six decarbonisation pathways. The "Electrification of uses" pathway ranked highest, demonstrating significant CO2 mitigation potential and high readiness (mean TRL 7.4, with two-thirds of technologies scoring over 7) despite challenges in hard-to-electrify sectors. The findings provide actionable insights for policymakers, highlighting the need for pathway-specific strategies, a deeper understanding of synergies between pathways, and balancing innovation with deployment to accelerate decarbonisation.
- GEMAS: Boron as a geochemical proxy for weathering of European agricultural soilPublication . Négrel, Philippe; Ladenberger, Anna; Demetriades, Alecos; Reimann, Clemens; Birke, Manfred; Sadeghi, Martiya; The EuroGeoSurveys GEMAS Project TeamABSTRACT: bout a century ago, B was recognised as an essential element for the normal growth of plants and terrestrial organisms. Limitations for plant development have been recognised in agricultural systems, particularly in highly weathered soil. Boron is rarely analysed in whole rock or soil analysis, as it requires specific analytical techniques. It is often determined, after partial extraction (aqua regia or Ca-Cl), usually on a limited number of samples. Many more questions than answers exist about the environmental behaviour of B. We present B contents in agricultural soil samples (0-10 cm) collected in 33 European countries (5.6 million km2) during the GEMAS (GEochemical Mapping of Agricultural and grazing land Soil) continental-scale project. The B content, determined by ICP-MS following hot aqua regia extraction, varies in European agricultural soil from 0.5 to 49 mg/kg (median 2.42 mg/kg, n = 2108), which is somewhat similar to total B estimates for the Upper Continental Crust (17-47 mg/kg). Its spatial distribution in agricultural soil shows a patchy pattern with low values in regions with granitic bedrock and high contents in soil formed over limestone and in volcanic areas. Boron geochemical behaviour in soil is strongly dependent on other factors such as pH, CEC, presence of organic matter, clay and secondary oxides and hydroxides. Boron geochemical mapping at the continental scale in arable soil allows investigations of plant health, i.e., the beneficial and adverse effects due to the nutritional status of boron.
- Palynology of the Albian–Turonian sediments from the Sumbe region, Kwanza Basin (Angola): Implications for paleoenvironment, paleoclimate, and paleogeographyPublication . Rodrigues, Cristina F.A.; Mendes, Márcia; Pereira, Zélia; Nsungani, P.C.; Fernandes, Paulo; Duarte, L. V.; Chitangueleca, Belarmino; Sebastião, Lumen; Aida, Benedito; Degli Esposti, Davide; Freitas, DomingosABSTRACT: 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.
- Parameter identification and uncertainty evaluation in quasi-dynamic test of solar thermal collectors with Monte Carlo methodPublication . Rodrigues, João Carlos Teixeira; Facão, Jorge; Carvalho, Maria JoãoABSTRACT: This work presents a comparison between two methods used for parameter identification and calculation of parameter uncertainty applied to the measured data of solar thermal collectors when tested according to ISO 9806:2017. One method is using a weighted least square (WLS) fit and the partial derivative approach described in the GUM (the Guide to the Expression of Uncertainty in Measurement). The second is using the Monte Carlo (MC) method, also described in GUM. Uncertainty evaluation by Monte Carlo method is based on a probabilistic approach and is an alternative way for identification of parameters and determination of the uncertainties. In this work the results were obtained according to Quasi-Dynamic Test (QDT) method for a flat plate collector and an evacuated tubular collector. The least squares (LS) method and a nonlinear regression method (MPFit) are used in the identification of parameters for each iteration of the MC method. For the implemented MC method computation times are also discussed. One disadvantage of the MC method is the computation time which depends on the number of samples in the experimental test quantity files, however with this study we think that the advantages of the MC method outweigh the disadvantages, and it is useful even as a complementary tool in QDT testing of collectors.