Browsing by Issue Date, starting with "2020-10"
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- New insights on the middle Givetian/middle Frasnian palynofloras from the Phyllite-Quartzite Formation in the Neves-Corvo mine region (Iberian Pyrite Belt, Portugal)Publication . Mendes, Márcia; Pereira, Zélia; Matos, João Xavier; Albardeiro, Luis; Morais, Igor; Solá, A. Rita; Salgueiro, Rute; Pacheco, Nelson; Araújo, Vítor; Inverno, Carlos; Oliveira, José TomásABSTRACT: A detailed palynostratigraphic study of two Somincor/Lundin Mining exploration drill holes intercepting the Phyllite-Quartzite (PQ) Formation in the geological basement of the Neves-Corvo mine region (Portuguese sector of the Iberian Pyrite Belt – IPB) allowed to first recognise the oldest ages for this formation in this region, ranging from midGivetian/midFrasnian (base unknown) to late Famennian. The TA Miospore Biozone (Cristatisporites triangulatus-Ancyrospora ancyrea) of middle Givetian age (Middle Devonian) was identified in NK30B-1 drill hole (Lombador North mine sector), whereas the BM Miospore Biozone (Verrucosisporites bulliferus-Lophozonotriletes media) and IV Miospore Biozone (based in the first occurrence of Rugospora bricei and Diducites cf. poljessicus) of middle Frasnian (Late Devonian) age were both recognised in drill hole SJ32 (Corvo-Semblana mine sector). The common presence of Early-Middle Devonian reworked spores, as well as similar inherited zircon ages may suggest that the lower PQ Formation age is not yet known. At Neves-Corvo mine, the Volcano-Sedimentary Complex is deposited directly above the PQ basement, spanning different ages, pointing out two major unconformities, a VSC/upper and/or lower PQ sequences and an upper PQ/lower PQ sequences. A palynostratigraphic correlation of the lowermost Phyllite-Quartzite Formation across the IPB is established. Phyllite-Quartzite Formation palynoassemblage of Neves-Corvo region is compared with lowermost PQ assemblages recovered in the NW sector of IPB (S. Francisco da Serra and Lousal-Caveira mine structures, Portugal) and in E sectors of the IPB in Spain (Gerena-El Garrobo section). The similar palynological record (also including the same reworked taxa signature) and ages obtained, suggests identical sedimentary provenance, close paleogeographic domain and temporal affinity throughout the lowermost IPB Phyllite-Quartzite Formation.
- Evento colisional e eventos térmicos proterozóicos registados pela monazite inclusa em corindo da região de Itaguara (Cratão São Francisco meridional, Brasil)Publication . De Oliveira Chaves, Alexandre; Dutra, A.Inclusões de cristais de monazite em corindo ocorrem no setor sul do Cratão São Francisco (Brasil) na região de Itaguara, no contacto entre rochas metaultramáficas e gnaisses envolvidos em tectónica colisional do evento Transamazónico paleoproterozóico. Diferentes domínios composicionais internos dos referidos cristais de monazite foram formados durante eventos térmicos regionais ocorridos ao longo do Paleoproterozóico. A datação destes domínios pelo método U-Th-Pb utilizando microssonda eletrónica revela sete idades distintas principais: 2126 ± 97 Ma, 1750 ± 78 Ma, 1495 ± 40 Ma, 1415 ± 41 Ma, 1200 ± 70 Ma, 1071 ± 26 Ma e 932 ± 77 Ma. A idade mais antiga é interpretada como a idade de cristalização da monazite e, em consequência, do próprio corindo gerado durante a referida tectónica colisional regional. As outras seis idades coincidem com as idades de diversos eventos térmicos regionais descritos na literatura, os quais estão geralmente relacionados à atividade de plumas mantélicas.
- New palynostratigraphic data of the Irati (Assistência Member) and the Corumbataí formations, Paraná Basin, Brazil, and correlation with other south American basinsPublication . Rocha, H.V.; Mendes, Márcia; Pereira, Zélia; Rodrigues, C.; Lopes, Gilda; Sant'Anna, L.G.; Tassinari, Colombo C. G.; Sousa, M.J. Lemos deABSTRACT: This research presents the palynostratigraphy of organic-rich shales from the Irati and the Corumbataí formations, Paraná Basin (PB), Southeastern Brazil, as part of an unconventional hydrocarbon source rock and CO2 reservoir assessment study. Thirty-four samples from the Corumbataí Formation and the Assistência Member of the Irati Formation were collected in the states of Goiás (northern border of the PB), São Paulo and Paraná (eastern and southern border of the PB, respectively). The acquired data allowed to establish a comprehensive palynostratigraphic study across the basin where a total of 18 pollen genera (34 pollen species), seven spore genera, four microplankton genera (1 species), and Chlorophyceae algae species where identified. The palynostratigraphic analysis also reveals a clear dominance of bisaccate pollen grains such as Corisaccites alutas, Lueckisporites virkkiae, and Weylandites lucifer. The Lueckisporites virkkiae zone was identified in the upper part of the Irati Formation (Assistência Member) and the lowermost part of the Corumbataí Formation, indicating a Kungurian to Roadian age for this part of the succession. Differences in the Guttulapollenites hannonicus and Tornopollenites toreutos biostratigraphic ranges, recovered in the Corumbataí Formation, suggest an earlier development of these species in the Paraná Basin during the middle Permian. Therefore, to evaluate the differences in the first occurrences of key species within the Paraná Basin, a close palynostratigraphic correlation between the main Guadalupian-Lopingian South American Gondwana basins is tentatively established.
- Seasonal Forecast Climate Data and Hydropower Production in the Douro Basin, in PortugalPublication . Diogo, Paulo; Beça, Pedro; Simoes, Sofia; Amorim, Filipa; Mujtaba, BabarABSTRACT: The project CLIM2POWER aims at developing a climate service including state-of-the art seasonal climate forecasts in the planning of the operation of the power systems. This work presents part of the project, addressing the forecasting of the hydropower generation in a case study area, the Portuguese part of the transboundary Douro River basin. Rainfall-runoff modelling was performed on a daily scale using three ensemble members of seasonal climate data (six months) for Portuguese territory crossed with three daily inflow scenarios from Spanish territory defined according to historical observed data. The obtained results reflect the fact that seasonal climate forecast present a wide variation of scenarios and also the fact that hydropower production in Portuguese territory is highly dependent on transboundary inflows. On the other hand, the implemented approach successfully produced consistent runoff and hydropower production results although improvements on the identification of the most probable scenarios are yet required.
- Solar Tower Testing Facility (STTF-100)Publication . Azevedo, Pedro; Cardoso, João P.ABSTRACT: The Concentrated Solar Power (CSP) research field denotes a high degree of multidisciplinarity, gathering several competences with regard to both exact sciences and engineering, such as optics, mechanics, thermodynamics, materials, chemistry, computation, control, instrumentation and so on.