GCG - Artigos em revistas internacionais
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Browsing GCG - Artigos em revistas internacionais by Sustainable Development Goals (SDG) "15:Proteger a Vida Terrestre"
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- Megaglomerospora lealiae nov. gen., nov. sp. from the upper Carboniferous of Portugal: the largest glomeromycotan fungal sporesPublication . Correia, Pedro; Sá, Artur A.; Pereira, ZéliaABSTRACT: A new genus and species of fossil fungus, Megaglomerospora lealiae, is described from the Bu & ccedil;aco Carboniferous Basin (upper Stephanian C, Upper Pennsylvanian, upper Carboniferous), in central western Portugal. The new fossil fungus consists of a dense cluster of silicified large spores. These new fungal spores are oblong, subelliptical to subspherical-shaped, with a glabrous surface characterized by having a lipid-filled lumen, and display a strong septate-like hypha attached. The presence of lobe-shaped germination shields suggests close affinities to Diversisporales (Glomeromycota). Megaglomerospora lealiae nov. gen., nov. sp. is remarkably distinctive because it is by far the largest fossil fungal spore (similar to 1.6 mm long) documented for the phylum Glomeromycota. This is the first report of an endomycorrhizal-like fungus from the Carboniferous of Iberia. (c) 2025 Elsevier Masson SAS. All rights are reserved, including those for text and data mining, AI training, and similar technologies.
- The old central igneous complexes of Sal, Boa Vista and Maio islands: Implications for 17 Ma of isotopic evolution of the Cape Verde archipelagoPublication . Villaseca, Carlos; Orejana, David; Huertas, Maria J.; Ancochea, Eumenio; Ignacio, Cristina; Mata, João; Caldeira, Rita; Garcia-Rodriguez, Maria; Moreno, Juan A.; Perez-Soba, CeciliaABSTRACT: The central igneous complexes of the easternmost islands (Sal, Boa Vista and Maio) preserve some of the most ancient outcropping rocks of the Cape Verde (CV) archipelago. These Early to Middle Miocene (about 25 to 12 Ma) complexes show marked isotopic differences between mafic rocks from the northern (Sal and Boa Vista) and the southern Maio Island, the latter showing lower 143Nd/144Nd, 206Pb/204Pb, 207Pb/204Pb, and higher 87Sr/86Sr ratios. The main mantle plume composition beneath Cape Verde is here considered to be dominated by the FOZO component. Our data supports previous models suggesting the incorporation to plume components of minor DMM mantle sources in the northern CV island alignment, whereas mixing with the EM1 pole is prevalent on the southern CV islands. These isotopic differences are evident since the early stages of Cape Verde magmatism. The Late Miocene to Holocene time period (7 to 1.7 Ma) is characterized by the irruption of silica-undersaturated and carbonatite magmas with a relatively homogeneous isotopic composition and highly radiogenic Pb signatures (206Pb/204Pb up to 20.6 in carbonatitic rocks and 20.2 in silicate rocks) throughout most of the Cape Verde archipelago. During this transitional stage, the input of this new HIMU mantle component overprinted the previous mixing of the main FOZO plume component with shallow mantle members (DMM, EM1) of minor contribution.
- Unprecedented U-Pb-Th SHRIMP and Lu-Hf isotopic data in zircon from Tandilia basement rocks, Argentina: new insights into Palaeoproterozoic and Neoproterozoic crustal reworking of the Rio de la Plata cratonPublication . Angeletti, Melisa; Chichorro, Martim Afonso; Castro, Antonio; Frisicale, María Cristina; Solá, A. Rita; Dimieri, Luis Vicente; Martinez, Juan CruzABSTRACT: We present new geochronological zircon data from the Siempre Amigos Hill (SAH), a small but representative portion of Tandilia Terrane within the R & iacute;o de la Plata Craton (RPC). U-Pb-Th SHRIMP data indicate a heterogeneous Palaeoproterozoic (Rhyacian) crust. A garnet-bearing granite (2165 +/- 16 Ma) hosts felsic (2108 +/- 13.6 Ma) to intermediate gneiss protolith (2104 +/- 8 Ma), andesite with a sanukitoid signature (2094 +/- 47 Ma) and granulites or charnockites. Additionally, calc-alkaline granitoids (2092 +/- 13 Ma) intruded, as a result of differentiation from an igneous mafic sanukitoid source. Localised low-temperature shear zones affected the sequence. Lu-Hf isotopic data for the post-orogenic stage (< 2.1 Ga) complement previous results, showing progressive negative epsilon Hf-(t) values. These isotopes suggest post-orogenic transtension. New Neoproterozoic ages (652 +/- 37 Ma, 618.4 +/- 11.2 Ma and 686 +/- 60 Ma) from granites, with low-to-very low zircon Th/U ratios, are presented as evidence of U-Th-Pb systems overprinting by Neoproterozoic (Cryogenian) thermal-hydrothermal events. Those Neoproterozoic ages are, within analytical uncertainty, equivalent to the 656 +/- 19 Ma metamorphic age obtained for the Palaeoproterozoic granulite. These new Neoproterozoic ages, suggests a thermal perturbation linked either to the collision of the Nico Perez Terrane against the passive margin of RPC, or the Neoproterozoic evolution of the Ventania System basement during the Brasiliano/ Pan-African orogeny.