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R D Tucker - One of the best experts on this subject based on the ideXlab platform.
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u pb zircon age for the Lagoa augen gneiss morais complex portugal tectonic implications
Journal of the Geological Society, 1993Co-Authors: R D Dallmeyer, R D TuckerAbstract:The Morais complex is a structural unit within a succession of allochthonous, exotic crystalline Variscan nappes exposed in northwestern Iberia. U-Pb analyses of tips broken from needle-like zircon in mylonitized Lagoa augen gneiss indicate a crystallization age of 496 +3 −2 Ma. Four other zircon fractions from the Lagoa augen gneiss suggest inherited zircon components with upper-intercept ages ranging between c. 2242 and 1941 Ma. The Cambrian to earliest Ordovician crystallization age is incompatible with previous interpretations of the Lagoa augen gneiss as Iberian Precambrian basement unconformably overlain by early Palaeozoic sedimentary rocks (Lagoa mica schist). The U-Pb results indicate that the Lagoa augen gneiss is coeval with, or perhaps younger than, the host sedimentary succession (the Lagoa mica schist). A 496 Ma crystallization age for the Lagoa augen gneiss is consistent with its derivation from an Avalonian-Cadomian source, at present situated west or northwest of the central Iberian autochthon.
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U-Pb zircon age for the Lagoa augen gneiss, Morais complex, Portugal: tectonic implications
1993Co-Authors: R D Dallmeyer, R D TuckerAbstract:Abstract: The Morais complex is a structural unit within a succession of allochthonous, exotic crystalline Variscan appes exposed in northwestern Iberia. U-Pb analyses of tips broken from needle-like zircon in mylonitized Lagoa augen gneiss indicate a crystallization age of 496 +3 Ma. Four other zircon fractions from the Lagoa augen gneiss suggest inherited zircon components with upper-intercept ages ranging between ¢. 2242 and 1941 Ma. The Cambrian to earliest Ordovician crystallization age is incompatible with previous interpretations of the Lagoa augen gneiss as Iberian Precambrian basement unconformably overlain by early Palaeozoic sedimentary ocks (Lagoa mica schist). The U-Pb results indicate that the Lagoa augen gneiss is coeval with, or perhaps younger than, the host sedimentary succession (the Lagoa mica schist). A 496 Ma crystallization age for the Lagoa augen gneiss is consistent with its derivation from an Avalonian-Cadomian source, at present situated west or northwest of the central Iberian autochthon. Northwestern Iberian segments of the Variscan orogen include several distinct exotic structural units (terranes) which are exposed in the Cabo Ortegal, Ordenes, Braganqa, and Morais complexes (Fig. 1; e.g. Ribeiro et al. 1990). These include an uppermost structural unit comprised of variably myloniti
Antonio R. M. - One of the best experts on this subject based on the ideXlab platform.
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O efeito do tamanho de partícula na lixiviação de Scirpus cubensis Poepp & Kunth
Instituto Internacional de Ecologia, 2003Co-Authors: I. Bianchini, Antonio R. M.Abstract:An investigation was made on the effects of detritus particle size on leaching rates in organic matter, and the associated environmental changes caused by detritus re-cycling in an oxbow lake (Lagoa do Infernão). Experiments were conducted during the decay of an aquatic macrophyte specie, S. cubensis, which in turn led to the formation of colored compounds. The S. cubensis were collected from the Lagoa do Infernão and taken to the laboratory where they were washed, dried, and fractionated using a sieve pedological set. The detritus was classified into six groups according to size, viz. 100, 10, 1.13, 0.78, 0.61, and 0.25 mm. Overall, the fragmentation process tended to increase the detritus fraction to be dissolved and to decrease the leaching rates owing to the possible dissolution of refracting matter. Fragmentation also caused the amount of colored compounds to increase and appeared to favor dissolved electrolyte release. Finally, in Lagoa do Infernão fragmentation is probably mediated by the metabolic action of benthic communities.Foram realizados estudos a fim de verificar os efeitos do tamanho de partícula dos fragmentos nos coeficientes de lixiviação da matéria orgânica e as mudanças, associadas ao ambiente, causadas pela ciclagem de detritos em uma Lagoa marginal (Lagoa do Infernão). Os experimentos foram desenvolvidos durante a decomposição de uma espécie de macrófita aquática, Scirpus cubensis, que também gerou compostos coloridos. Os exemplares de S. cubensis foram coletados na Lagoa do Infernão e levados ao laboratório, onde foram lavados, secos e fracionados em um conjunto de peneiras pedológicas. Os detritos foram classificados em seis grupos, de acordo com o tamanho: 100, 10, 1,13, 0,78, 0,61 e 0,25 mm. No geral, o processo de fragmentação tendeu a incrementar a fração do detrito a ser dissolvida e diminuir os coeficientes de lixiviação, em razão de possível dissolução da matéria orgânica refratária. A fragmentação também favoreceu a formação de compostos coloridos e a liberação de eletrólitos dissolvidos. Na Lagoa do Infernão, a fragmentação, provavelmente, é mediada pela ação metabólica da comunidade bentônica
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The effect of particle size on the leaching of Scirpus cubensis Poepp & Kunth
Instituto Internacional de Ecologia, 2003Co-Authors: Bianchini Jr.,i., Antonio R. M.Abstract:An investigation was made on the effects of detritus particle size on leaching rates in organic matter, and the associated environmental changes caused by detritus re-cycling in an oxbow lake (Lagoa do Infernão). Experiments were conducted during the decay of an aquatic macrophyte specie, S. cubensis, which in turn led to the formation of colored compounds. The S. cubensis were collected from the Lagoa do Infernão and taken to the laboratory where they were washed, dried, and fractionated using a sieve pedological set. The detritus was classified into six groups according to size, viz. 100, 10, 1.13, 0.78, 0.61, and 0.25 mm. Overall, the fragmentation process tended to increase the detritus fraction to be dissolved and to decrease the leaching rates owing to the possible dissolution of refracting matter. Fragmentation also caused the amount of colored compounds to increase and appeared to favor dissolved electrolyte release. Finally, in Lagoa do Infernão fragmentation is probably mediated by the metabolic action of benthic communities
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The effect of particle size on the leaching of Scirpus cubensis Poepp & Kunth
Instituto Internacional de Ecologia, 2003Co-Authors: Antonio R. M.Abstract:An investigation was made on the effects of detritus particle size on leaching rates in organic matter, and the associated environmental changes caused by detritus re-cycling in an oxbow lake (Lagoa do Infernão). Experiments were conducted during the decay of an aquatic macrophyte specie, S. cubensis, which in turn led to the formation of colored compounds. The S. cubensis were collected from the Lagoa do Infernão and taken to the laboratory where they were washed, dried, and fractionated using a sieve pedological set. The detritus was classified into six groups according to size, viz. 100, 10, 1.13, 0.78, 0.61, and 0.25 mm. Overall, the fragmentation process tended to increase the detritus fraction to be dissolved and to decrease the leaching rates owing to the possible dissolution of refracting matter. Fragmentation also caused the amount of colored compounds to increase and appeared to favor dissolved electrolyte release. Finally, in Lagoa do Infernão fragmentation is probably mediated by the metabolic action of benthic communities
R D Dallmeyer - One of the best experts on this subject based on the ideXlab platform.
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u pb zircon age for the Lagoa augen gneiss morais complex portugal tectonic implications
Journal of the Geological Society, 1993Co-Authors: R D Dallmeyer, R D TuckerAbstract:The Morais complex is a structural unit within a succession of allochthonous, exotic crystalline Variscan nappes exposed in northwestern Iberia. U-Pb analyses of tips broken from needle-like zircon in mylonitized Lagoa augen gneiss indicate a crystallization age of 496 +3 −2 Ma. Four other zircon fractions from the Lagoa augen gneiss suggest inherited zircon components with upper-intercept ages ranging between c. 2242 and 1941 Ma. The Cambrian to earliest Ordovician crystallization age is incompatible with previous interpretations of the Lagoa augen gneiss as Iberian Precambrian basement unconformably overlain by early Palaeozoic sedimentary rocks (Lagoa mica schist). The U-Pb results indicate that the Lagoa augen gneiss is coeval with, or perhaps younger than, the host sedimentary succession (the Lagoa mica schist). A 496 Ma crystallization age for the Lagoa augen gneiss is consistent with its derivation from an Avalonian-Cadomian source, at present situated west or northwest of the central Iberian autochthon.
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U-Pb zircon age for the Lagoa augen gneiss, Morais complex, Portugal: tectonic implications
1993Co-Authors: R D Dallmeyer, R D TuckerAbstract:Abstract: The Morais complex is a structural unit within a succession of allochthonous, exotic crystalline Variscan appes exposed in northwestern Iberia. U-Pb analyses of tips broken from needle-like zircon in mylonitized Lagoa augen gneiss indicate a crystallization age of 496 +3 Ma. Four other zircon fractions from the Lagoa augen gneiss suggest inherited zircon components with upper-intercept ages ranging between ¢. 2242 and 1941 Ma. The Cambrian to earliest Ordovician crystallization age is incompatible with previous interpretations of the Lagoa augen gneiss as Iberian Precambrian basement unconformably overlain by early Palaeozoic sedimentary ocks (Lagoa mica schist). The U-Pb results indicate that the Lagoa augen gneiss is coeval with, or perhaps younger than, the host sedimentary succession (the Lagoa mica schist). A 496 Ma crystallization age for the Lagoa augen gneiss is consistent with its derivation from an Avalonian-Cadomian source, at present situated west or northwest of the central Iberian autochthon. Northwestern Iberian segments of the Variscan orogen include several distinct exotic structural units (terranes) which are exposed in the Cabo Ortegal, Ordenes, Braganqa, and Morais complexes (Fig. 1; e.g. Ribeiro et al. 1990). These include an uppermost structural unit comprised of variably myloniti
I. Bianchini - One of the best experts on this subject based on the ideXlab platform.
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O efeito do tamanho de partícula na lixiviação de Scirpus cubensis Poepp & Kunth
Instituto Internacional de Ecologia, 2003Co-Authors: I. Bianchini, Antonio R. M.Abstract:An investigation was made on the effects of detritus particle size on leaching rates in organic matter, and the associated environmental changes caused by detritus re-cycling in an oxbow lake (Lagoa do Infernão). Experiments were conducted during the decay of an aquatic macrophyte specie, S. cubensis, which in turn led to the formation of colored compounds. The S. cubensis were collected from the Lagoa do Infernão and taken to the laboratory where they were washed, dried, and fractionated using a sieve pedological set. The detritus was classified into six groups according to size, viz. 100, 10, 1.13, 0.78, 0.61, and 0.25 mm. Overall, the fragmentation process tended to increase the detritus fraction to be dissolved and to decrease the leaching rates owing to the possible dissolution of refracting matter. Fragmentation also caused the amount of colored compounds to increase and appeared to favor dissolved electrolyte release. Finally, in Lagoa do Infernão fragmentation is probably mediated by the metabolic action of benthic communities.Foram realizados estudos a fim de verificar os efeitos do tamanho de partícula dos fragmentos nos coeficientes de lixiviação da matéria orgânica e as mudanças, associadas ao ambiente, causadas pela ciclagem de detritos em uma Lagoa marginal (Lagoa do Infernão). Os experimentos foram desenvolvidos durante a decomposição de uma espécie de macrófita aquática, Scirpus cubensis, que também gerou compostos coloridos. Os exemplares de S. cubensis foram coletados na Lagoa do Infernão e levados ao laboratório, onde foram lavados, secos e fracionados em um conjunto de peneiras pedológicas. Os detritos foram classificados em seis grupos, de acordo com o tamanho: 100, 10, 1,13, 0,78, 0,61 e 0,25 mm. No geral, o processo de fragmentação tendeu a incrementar a fração do detrito a ser dissolvida e diminuir os coeficientes de lixiviação, em razão de possível dissolução da matéria orgânica refratária. A fragmentação também favoreceu a formação de compostos coloridos e a liberação de eletrólitos dissolvidos. Na Lagoa do Infernão, a fragmentação, provavelmente, é mediada pela ação metabólica da comunidade bentônica
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The effect of particle size on the leaching of Scirpus cubensis Poepp & Kunth O efeito do tamanho de partícula na lixiviação de Scirpus cubensis Poepp & Kunth
Instituto Internacional de Ecologia, 2003Co-Authors: I. Bianchini, R. M. AntonioAbstract:An investigation was made on the effects of detritus particle size on leaching rates in organic matter, and the associated environmental changes caused by detritus re-cycling in an oxbow lake (Lagoa do Infernão). Experiments were conducted during the decay of an aquatic macrophyte specie, S. cubensis, which in turn led to the formation of colored compounds. The S. cubensis were collected from the Lagoa do Infernão and taken to the laboratory where they were washed, dried, and fractionated using a sieve pedological set. The detritus was classified into six groups according to size, viz. 100, 10, 1.13, 0.78, 0.61, and 0.25 mm. Overall, the fragmentation process tended to increase the detritus fraction to be dissolved and to decrease the leaching rates owing to the possible dissolution of refracting matter. Fragmentation also caused the amount of colored compounds to increase and appeared to favor dissolved electrolyte release. Finally, in Lagoa do Infernão fragmentation is probably mediated by the metabolic action of benthic communities.Foram realizados estudos a fim de verificar os efeitos do tamanho de partícula dos fragmentos nos coeficientes de lixiviação da matéria orgânica e as mudanças, associadas ao ambiente, causadas pela ciclagem de detritos em uma Lagoa marginal (Lagoa do Infernão). Os experimentos foram desenvolvidos durante a decomposição de uma espécie de macrófita aquática, Scirpus cubensis, que também gerou compostos coloridos. Os exemplares de S. cubensis foram coletados na Lagoa do Infernão e levados ao laboratório, onde foram lavados, secos e fracionados em um conjunto de peneiras pedológicas. Os detritos foram classificados em seis grupos, de acordo com o tamanho: 100, 10, 1,13, 0,78, 0,61 e 0,25 mm. No geral, o processo de fragmentação tendeu a incrementar a fração do detrito a ser dissolvida e diminuir os coeficientes de lixiviação, em razão de possível dissolução da matéria orgânica refratária. A fragmentação também favoreceu a formação de compostos coloridos e a liberação de eletrólitos dissolvidos. Na Lagoa do Infernão, a fragmentação, provavelmente, é mediada pela ação metabólica da comunidade bentônica
Fernanda Igual Morales - One of the best experts on this subject based on the ideXlab platform.
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Associação da ocorrência de cianobactérias às variações de qualidade do efluente na Lagoa de estabilização de Santa Eudóxia São Carlos, SP e suas interferências no corpo receptor
Universidade Federal de São Carlos, 2015Co-Authors: Fernanda Igual MoralesAbstract:As Lagoas de estabilização de esgotos são um método eficiente de decomposição de matéria orgânica no tratamento de esgoto doméstico. Tanto fatores bióticos como abióticos agem nas Lagoas. As cianobactérias são um dos fatores bióticos de grande importância para o processo de purificação do esgoto. Grande quantidade de nutriente pode resultar em alta densidade de cianobactérias, caracterizando eutrofização. Estas podem liberar cianotoxinas que podem prejudicar a saúde humana e animal quando em contato. Parâmetros físico-químicos estão associados tanto à presença de cianobactérias quanto à qualidade do corpo receptor e permite avaliar o atendimento ou não dos padrões exigidos pelas legislações. Correlacionar a densidade de cianobactérias com os parâmetros físico-químicos e avaliar o corpo receptor em relação ao efluente lançado, foram os objetivos deste trabalho. Foram realizadas análises quantitativas e qualitativas de cianobactérias, análises dos parâmetros físico-químicos de acordo com manual da Hach, e análise estatística (análise de Regressão). As análises de fósforo e nitrogênio apresentam valores próximos aos encontrados na literatura. Porém valores de fósforo à jusante demonstram inadequação com a legislação. A temperatura na Lagoa é mais elevada que no rio, caracterizada pelas reações bioquímicas que ocorrem nesse ambiente. A concentração de oxigênio dissolvido esteve dentro dos padrões e se manteve em relação à estudos anteriores. O pH e a turbidez também atenderam à legislação. Foi constatada, através de modelo matemático, que houve estratificação térmica na maioria dos meses de coleta na Lagoa, estando a Lagoa, em mistura completa em somente quatro meses. A análise estatística demonstrou correlação positiva entre cianobactérias e concentração de nitrogênio total, porém correlação negativa com a temperatura do efluente. Em relação às cianobactérias, na Lagoa os principais gêneros encontrados foram Merismopedia, Oscillatoria e Pseudanabaena e no rio tanto à montante quanto à jusante foram Microcystis, Pseudanabaena e Limnothrix, evidenciando o potencial tóxico desses indivíduos na água. Os valores de cianobactérias no rio principalmente à jusante excederam o valor limite da legislação. Em geral, alguns parâmetros excederam os limites, mas não prejudicam fortemente a qualidade do corpo receptor.Wastewater stabilization ponds are an efficient method of decomposition organic matter in sewage treatment. Both biotic factors such as abiotic act in the ponds. Cyanobacteria are one of biotic factors of great importance to the process of sewage purification. Lot of nutrients can can result in high density cyanobacteria, characterized as eutrophication. These can release cyanotoxins that can harm health human and animal when in contact with them. Physical and chemical parameters are associated with both the presence of cyanobacteria and with the quality of the receiving body and allows evaluating compliance or not the standards required by legislation. Correlate the cyanobacteria density with the physical and chemical parameters and evaluate the receiving body in relation to the released effluent, were the objectives of this work. Quantitative and qualitative analysis of cyanobacteria were realized, and analyzes of the physico-chemical parameters according to Hach manual, and statistical analysis (regression analysis). The phosphorus and nitrogen analyzes have values close to those found in the literature. But phosphorus values downstream demonstrate inadequacy with the rules. The temperature in the pond is higher than the river, characterized by biochemical reactions that take place in this environment. The dissolved oxygen concentration was within the standards and remained in relation to previous studies. The pH and turbidity also attended the law. It has been found through mathematical model, which was thermal stratification in most months in the pond, with the pond in complete mixing in only four months. Statistical analysis showed a positive correlation between cyanobacteria and total nitrogen concentration, but a negative correlation with the effluent temperature. About the cyanobacteria in the pond the main genera found were Merismopedia, Oscillatoria and Pseudanabaena and in the river both upstream as downstream were Microcystis, Pseudanabaena and Limnothrix, indicating the toxic potential of these individuals in the water. The cyanobacteria values in the river downstream mainly, exceeded the value limit of the legislation. In general, some parameters exceeded the limits, but not damaged strongly the quality of the receiving body
