109 research outputs found

    Transition between Variscan and Alpine cycles in the Pyrenean-Cantabrian Mountains (N Spain): Geodynamic evolution of near-equator European Permian basins

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    In the northern Iberian Peninsula, the Pyrenean-Cantabrian orogenic belt extends E-W for ca. 1000 km between the Atlantic Ocean and Mediterranean Sea. This orogen developed from the collision between Iberia and Eurasia, mainly in Cenozoic times. Lower-middle Permian sediments crop out in small, elongated basins traditionally considered independent from each other due to misinterpretations on incomplete lithostratigraphic data and scarce radiometric ages. Here, we integrate detailed stratigraphic, sedimentary, tectonic, paleosol and magmatic data from well-dated lithostratigraphic units. Our data reveal a similar geodynamic evolution across the Pyrenean-Cantabrian Ranges at the end of the Variscan cycle. Lower-middle Permian basins started their development under an extensional regime related to the end of the Variscan Belt collapse, which stars in late Carboniferous times in the Variscan hinterland. This orogenic collapse transitioned to Pangea breakup at the middle Permian times in the study region. Sedimentation occurred as three main tectono-sedimentary extensional phases. A first phase (Asselian-Sakmarian), which may have even started at the end of the Carboniferous (Gzhelian) in some sections, is mainly represented by alluvial sedimentation associated with calc-alkaline magmatism. A second stage (late Artinskian-early Kungurian), represented by al-luvial, lacustrine and palustrine sediments with intercalations of calc-alkaline volcanic beds, shows a clear up-ward aridification trend probably related to the late Paleozoic icehouse-greenhouse transition. The third and final stage (Wordian-Capitanian) comprised of alluvial deposits with intercalations of alkaline and mafic beds, rarely deposited in the Cantabrian Mountains, and underwent significant pre-and Early Mesozoic erosion in some segments of the Pyrenees. This third stage can be related to a transition towards the Pangea Supercontinent breakup, not generalized until the Early/Middle Triassic at this latitude because the extensional process stopped about 10 Myr (Pyrenees) to 30 Myr (Cantabrian Mountains). When compared to other well-dated basins near the paleoequator, the tectono-sedimentary and climate evolution of lower-middle Permian basins in Western and Central Europe shows common features. Specifically, we identify coeval periods with magmatic activity, extensional tectonics, high subsidence rates and thick sedi-mentary record, as well as prolonged periods without sedimentation. This comparison also identifies some evolutionary differences between Permian basins that could be related to distinct locations in the hinterland or foreland of the Variscan orogen. Our data provide a better understanding of the major crustal re-equilibration and reorganization that took place near the equator in Western-Central Europe during the post-Variscan period

    Behavior of congenital malformations in Guantanamo during the year 2010

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    Se realiza un estudio con el objetivo de caracterizar el comportamiento de algunas variables en el pesquisaje de malformaciones congénitas en gestantes de la provincia de Guantánamo, en el período enero-diciembre de 2010. El universo está constituido por 7 585 nacimientos y la muestra por 76 malformaciones que se produjeron en ese período, con utilización del muestreo aleatorio simple. Se concluye: que la tasa de mortalidad por malformaciones congénitas de la provincia de Guantánamo es de 1.18 por 1 000 nacidos vivos, las malformaciones más frecuentes encontradas corresponden a las del sistema nervioso central, el cardiovascular y el osteomioarticular, la frecuencia de malformaciones encontradas fue de 1.00 %. El grupo etario con mayor incidencia fue el de 20 a 29 años de edad, el municipio con mayor tasa fue Imías. Los medios diagnósticos más utilizados fueron el ultrasonido, seguidos de la alfafetoproteínas, y los estudios cito genéticos. A study was carried out to characterize the behavior of some variables in the screening of congenital malformations in pregnant women in Guantanamo, in the period January-December 2010. The universe is constituted by 7 585 births and the sample by 76 Malformations that occurred in that period, using simple random sampling. It is concluded that the mortality rate for congenital malformations in Guantanamo province is 1.18 per 1,000 live births, the most frequent malformations found correspond to those of the central nervous system, cardiovascular and osteomioarticular, the frequency of malformations found was of 1.00%. The age group with the highest incidence was 20 to 29 years of age; the municipality with the highest rate was Imías. The most commonly used diagnostic tools were ultrasound, followed by alpha-fetoproteins, and genetic cito studies

    Constraining the Permian/Triassic transition in continental environments: Stratigraphic and paleontological record from the Catalan Pyrenees (NE Iberian Peninsula)

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    The continental Permian–Triassic transition in southern Europe presents little paleontological evidence of the Permian mass extinction and the subsequent faunal recovery during the early stages of the Triassic. New stratigraphic, sedimentological and paleontological analyses from Middle–Upper Permian to Lower–Middle Triassic deposits of the Catalan Pyrenees (NE Iberian Peninsula) allow to better constrain the Permian–Triassic succession in the Western Tethys basins, and provide new (bio-) chronologic data. For the first time, a large vertebra attributed to a caseid synapsid from the ?Middle Permian is reported from the Iberian Peninsula—one of the few reported from western Europe. Osteological and ichnological records from the Triassic Buntsandstein facies reveal a great tetrapod ichnodiversity, dominated by small to medium archosauromorphs and lepidosauromorphs (Rhynchosauroides cf. schochardti, R. isp. 1 and 2, Prorotodactylus–Rotodactylus), an undetermined Morphotype A and to a lesser degree large archosaurians (chirotheriids), overall suggesting a late Early Triassic–early Middle Triassic age. This is in agreement with recent palynological analyses in the Buntsandstein basal beds that identify different lycopod spores and other bisaccate and taeniate pollen types of late Olenekian age (Early Triassic). The Permian caseid vertebra was found in a playa-lake setting with a low influence of fluvial water channels and related to the distal parts of alluvial fans. In contrast, the Triassic Buntsandstein facies correspond to complex alluvial fan systems, dominated by high-energy channels and crevasse splay deposits, hence a faunal and environmental turnover is observed. The Pyrenean biostratigraphical data show similarities with those of the nearby Western Tethys basins, and can be tentatively correlated with North African and European basins. The Triassic Pyrenean fossil remains might rank among the oldest continental records of the Western Tethys, providing new keys to decipher the Triassic faunal biogeography and recovery.E. Mujal and J. Fortuny received funding from the SYNTHESYS Project http://www.synthesys.info/ (DE-TAF-2560, FR-TAF-3621, FR-TAF-4808 to E. Mujal and FR-TAF-435 and FR-TAF-3353 to J. Fortuny) which is financed by European Community Research Infrastructure Action under the FP7 “Capacities” Program. E. Mujal acknowledges “Secretaria d'Universitats i de Recerca del Departament d'Economia i Coneixement de la Generalitat de Catalunya” (E.M., expedient number 2013 CTP 00013, at ISE-M, Université Montpellier-2) for funding used for visiting collections. E. Mujal obtained financial support from the PIF grant of the Geology Department at UAB. A. Arche, J. Barrenechea, R. De la Horra, J.B. Diez and J. López-Gómez received support from the CGL2011-24408 and CGL2014-52699 research projects of the Spanish Ministerio de Economía y Competitividad. This paper is also a contribution to the following research projects: “Sistemas Sedimentarios y Variabilidad Climática” (642853) of the CSIC, and Basin Analysis (910429), and Palaeoclimatology and Global Change (910198) of the Universidad Complutense de Madrid. J. Fortuny acknowledges the support of the Generalitat de Catalunya postdoc grant 2014 – BP-A 00048. Fieldwork campaigns have been developed under the projects “Vertebrats del Permià i el Triàsic de Catalunya i el seu context geològic” and “Evolució dels ecosistemes amb faunes de vertebrats del Permià i el Triàsic de Catalunya” (ref. 2014/100606), based by the Institut Català de Paleontologia and carried out thanks to the financial support of the Departament de Cultura (Generalitat de Catalunya).Peer reviewe

    Proceedings of the Fifth Italian Conference on Computational Linguistics CLiC-it 2018

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    On behalf of the Program Committee, a very warm welcome to the Fifth Italian Conference on Computational Linguistics (CLiC-­‐it 2018). This edition of the conference is held in Torino. The conference is locally organised by the University of Torino and hosted into its prestigious main lecture hall “Cavallerizza Reale”. The CLiC-­‐it conference series is an initiative of the Italian Association for Computational Linguistics (AILC) which, after five years of activity, has clearly established itself as the premier national forum for research and development in the fields of Computational Linguistics and Natural Language Processing, where leading researchers and practitioners from academia and industry meet to share their research results, experiences, and challenges
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