Thesis (doctoral)--Universität Bremen, 2005. / Includes bibliographical references (p. 159-171). Also available on the Internet.

Thesis (M.S.)--Florida State University, 2006. / Advisor: Joel Kostka, Florida State University, College of Arts and Sciences, Dept. of Oceanography. Title and description from dissertation home page (viewed Oct. 24, 2006). Document formatted into pages; contains viii, 101 pages. Includes bibliographical references.

A Oceanografia, recentemente, vem fazendo uso dos mais diferentes radionuclídeos os quais funcionam como traçadores e auxiliam em uma maior compreensão dos processos de dinâmica oceânica, movimentação e deposição do fundo marinho. No Brasil, porém, há pouca informação a respeito dos teores de radionuclídeos naturais para a região costeira e oceânica e poucos são os estudos que utilizam esses radionuclídeos como ferramentas de compreensão de processos oceânicos. Neste contexto, este trabalho determinou atividades de 238U, 232Th e 40K por espectrometria gama e realizou análises granulométricas em amostras de sedimentos marinhos da Margem Continental Sudeste do Brasil. Os níveis variaram de 1,48 a 52,76 Bq kg-1 para o 238U, 10,63 a 49,45 Bq kg-1 para o 232Th e 65,45 a 873,28 Bq kg-1 para o 40K. Os resultados mostraram afinidade entre as frações finas do sedimento com 40K e 232Th. A razão 238U/232Th mostrou ser bom indicador de condições redox dos sedimentos. Verificou-se uma diferença nos níveis dos três radionuclídeos entre os setores ao norte e ao sul da Ilha de São Sebastião, com valores mais elevados ao sul. Estas diferenças foram relacionadas aos processos sedimentares dominantes em cada setor e aos agentes hidrodinâmicos responsáveis por tais processos. / Recently, Oceanography has been using a variety of radionuclides as tracers to understand ocean dynamic processes, handling and disposal of sediments in seabed. In Brazil, there is little information about the contents of natural radionuclides on the coast and deep ocean and few studies using radionuclides as tools to comprehend oceanic processes. In this context, this work determined grain size and activities of 238U, 232Th and 40K using gamma spectrometry in marine sediments from shelf and upper slope off Southeast Brazil. The levels ranged from 1,48 to 52,76 Bq kg-1 for 238U, from 10,63 to 49,45 Bq kg-1 for 232Th and, from 65,45 to 873,28 Bq kg-1 for 40K. 40K and 232Th showed good correlation with grain size (mud and clay content) and 238U/232Th ratios appeared to be good indicators of sediment redox conditions. There was a difference in levels of radionuclides between sectors northward and southward of São Sebastião Island, with higher values in south sector. These differences were related to differences in sedimentary processes in each sector and to the hydrodynamic agents responsible for these processes.

Regiões onde existem atividades portuárias estão mais susceptíveis à contaminação por hidrocarbonetos devido ao trânsito de embarcações e as operações de carga/descarga e, consequentemente, estão mais vulneráveis a sofrer impactos ambientais. Este trabalho avaliou a composição, distribuição e origem de hidrocarbonetos em oito regiões portuárias da costa sudeste brasileira: Santos-SP, São Sebastião-SP, Angra dos Reis-RJ, Itaguaí-RJ, Rio de Janeiro-RJ, Arraial do Cabo-RJ, Macaé-RJ e Vitória-ES. Foram coletadas amostras de sedimentos marinhos superficiais (02 cm) em duas campanhas (2009 e 2010). Para a análise dos hidrocarbonetos alifáticos e dos hidrocarbonetos policíclicos aromáticos (HPAs) foram utilizadas cromatografia em fase gasosa com detector de ionização de chama e cromatografia em fase gasosa acoplada à espectrometria de massas, respectivamente. As concentrações médias e os desvios-padrão do Total de nalcanos (μg g-1), Total de Alifáticos (μg g-1), HPAs Totais (ng g-1) e 16 HPAs prioritários (ng g-1) encontrados foram 6,55 4,52, 123,16 86,12, 1470,24 958,41 e 653,93 482,81 na região do porto de Santos-SP; 2,69 1,16, 35,29 15,22, 756,25 350,28 e 142,35 142,35 na região do porto de São Sebastião-SP; 3,11 2,34, 56,99 78,39, 777,62 821,32 e 82,33 84,62 na região do porto de Angra dos Reis-RJ; 5,58 3,28, 26,55 12,19, 1221,15 1070,87 e 92,28 93,14 na região do porto de Itaguaí-RJ; 5,09 2,03, 179,22 108,16, 3547,27 3081,18 e 1879,05 1792,69 na região do porto do Rio de Janeiro; 1,63 2,15, 51,54 39,50, 366,26 222,89 e 194,83 141,65 na região do porto de Arraial do Cabo-RJ; 3,92 2,69, 50,42 81,30, 643,97 637,61 e 182,46 265,87 na região do porto de Macaé-RJ; e 4,78 4,05, 45,31 32,84, 868,78 874,56 e 258,84 142,89 na região do porto de Vitória-ES, respectivamente. O nível de contaminação por hidrocarbonetos nas regiões estudadas variou de baixo a muito alto, mostrando que estes níveis não são diretamente compatíveis com o tamanho e o desenvolvimento urbano em torno de cada porto. Para a avaliação das fontes de contaminação foram usadas razões diagnósticas selecionadas da literatura. A mistura de fontes (pirolítica e petrogênica) foi considerada predominante na maioria das áreas, indicando a influência das atividades dos portos e dos aportes de entradas de contaminação por vias urbanas, industriais e atmosféricas. / Regions where there are port activities are more susceptible to contamination by hydrocarbons due to transit of vessels and loading/unloading operations and, consequently, are more vulnerable to environmental impacts. This study evaluated the composition, distribution, and origin of hydrocarbons in eight ports in Southeastern Brazilian coast: Santos-SP, São Sebastião-SP, Angra dos Reis-RJ, Itaguaí-RJ, Rio de Janeiro-RJ, Arraial do Cabo-RJ, Macaé-RJ and Vitória-ES. Samples were collected from shallow marine sediments (0-2) in two years (2009 and 2010). Gas chromatography with flame ionization detector and gas chromatography coupled to mass espectrometria were respectively used to analyze the aliphatic hydrocarbons and polycyclic aromatic hydrocarbons (HPAs) Average concentration and standard deviations of n-alkanes (μg g-1), Total Aliphatic (μg g-1), 16 priority HPAs (ng g-1) and Total HPAs (ng g-1) were 6.55 4.52, 123.16 86.12, 1470.24 958.41 and 653.93 482.81 in the region of Santos; 2.69 1.16, 35.29 15.22, 756.25 350.28 and 142.35 142.35 in the region São Sebastião; 3,11 2,34, 56,99 78,39, 777,62 821,32 and 82,33 84,62 in the region of Angra dos Reis; 5,58 3,28, 26,55 12,19, 1221,15 1070,87 and 92,28 93,14 in the region of Itaguaí; 5,09 2,03, 179,22 108,16, 3547,27 3081,18 and 1879,05 1792,69 in the region of Rio de Janeiro; 1.63 2.15, 51.54 39.50, 366.26 222.89 and 194.83 141.65 in the region of Arraial do Cabo; 3.92 2.69, 50.42 81.30, 643.97 637.61 and 182.46 265.87 in the region of Macae; and 4,78 4,05, 45,31 32,84, 868,78 874,56 and 258,84 142,89 in the region of Vitória, respectively. Contamination by oil in those studied regions was variable and could not be straightly related to the size and urban development around each port. In order to evaluate sources of contamination it were used selected diagnostic reasons. Contamination in most of areas revealed to be simultaneously influenced by a mix of sources (pyrolytic and petrogenic), probably related to port activities, urban and industrial wastes, and atmospheric routes.

Une analyse expérimentale approfondie avec une approche micro macro a été réalisée sur un matériaucomposé d’un mélange d’argile Kaolinite/Smectite. L’étude a permis de montrer à l’échelle macroscopiquecomme à l’échelle microscopique un comportement particulièrement sensible à la proportion de smectitedans le mélange. La kaolinite (Kaolinite P300) est bien connue du point de vu de sa caractérisation et deson comportement, la smectite (également nommée argile grecque) est de type calcique et a égalementfait l’objet de plusieurs études.Dès 35% de smectite dans le mélange, les résultats sur chemin triaxial montrent que le comportementapproche considérablement celui de la smectite. Par ailleurs, l’investigation à l’échelle microscopique (aumoyen de Microscope Electronique à Balayage complétée par une analyse de diffractions des rayons X)réalisé sur les échantillons après l’essai, met en évidence le fait que, lorsqu’elle dépasse un certain seuil, lafraction en smectite favorise le développement de plans de glissement. Ces plans apparaissent clairementsous forme de groupes de particules de smectite orientées.L’analyse microstructurale utilisée est basée sur une méthode rigoureuse, développée dans le cadre decette thèse, avec un traitement d’images automatisé permettant de fournir des résultats quantitatifs.Cette démarche d’investigation multi‐échelles a été employée afin caractériser le comportement d’unsédiment marin prélevé au large de Golfe de Guinée par 700 m de profondeur d’eau. L’étude, initialementmenée dans le cadre du projet CLAROM (2002‐2005), intéresse l’industrie Offshore. Le sédiment naturelcontient jusqu’à 60% de proportion argileuse avec approximativement 15% de smectite et 50% dekaolinite. / A thorough experimental analysis with a micro macro approach was performed on a material composed ofa mixture of Kaolinite / Smectite clays. The study showed at macroscopic scale as the microscopic scalethat the behaviour is particularly sensitive to the proportion of smectite in the mixture. Kaolinite(Kaolinite P300) is well known from the point of view of characterization and behaviour, smectite (also called Greek clay) is a calcic type and was also the subject of several studies.From 35% of smectite in the mixture, the results show that the behaviour on triaxial path approachconsiderably to that of smectite. Furthermore, investigation on the microscopic level (using scanningelectron microscope supplemented by X‐ray diffraction analysis) performed on the samples after the testshows that, if it exceeds a certain threshold, the smectite fraction promotes the development of slipplanes. These plans are evident as oriented groups of particles of smectite.The used microstructural analysis is based on a rigorous method, developed in the context of this thesis,with an automated image processing to provide quantitative results.This multi‐scale investigation has been used to characterize the behaviour of a marine sediment taken ofGulf of Guinea by 700 m water depth. The study, originally conducted in the CLAROM project (2002‐2005), interested to the offshore industry. The natural sediment contains up to 60% proportion of claywith approximately 15% smectite and 50% kaolinite.

Orientador: Francisco Sergio Bernardes Ladeira / Dissertação (mestrado) - Universidade Estadual de Campinas, Instituto de Geociencias / Made available in DSpace on 2018-08-14T18:02:11Z (GMT). No. of bitstreams: 1 Gobbi_EstefanoSeneme_M.pdf: 7278814 bytes, checksum: 64613abcee7f68675085c8622fe0786f (MD5) Previous issue date: 2009 / Resumo: A Planície Sedimentar de Caraguatatuba pode ser considerada como exceção em relação às outras planícies que a circundam. Entre o Canal de São Sebastião (SP) e Cabo Frio (RJ) predominam praias descontinuas, segregadas por indentações do Planalto Atlântico, que por vezes sofrem abrasão direta do oceano. As praias do litoral norte paulista e sul fluminense são denominadas de "praias de bolso" (poket beachs), por apresentaram uma planície de sedimentação em tamanho reduzido, de modo a adentrar pouco no continente. No entanto, na área da Planície de Caraguatatuba, as escarpas possuem um distancia de até 12 Km da atual linha de arrebentação e a baía possui uma abertura da ordem de 10 Km, descaracterizada, portanto, das demais planícies próximas. Esse fato é decorrência a fatores geológicos e estruturais, da Serra do Mar, bem como da presença da intrusão alcalina da Ilha de São Sebastião, que possibilitam a sedimentação na área. Esta sedimentação ocorre por conta da deposição por ação marinha e/ou fluvial. Durante o Período Quaternário ocorreram mudanças no nível relativo dos mares (variações glácio-eustáticas), que proporcionaram avanços e recuos da linha de costa. Desta maneira, ao adquirir patamares mais elevados, a abrasão marinha atingiu determinadas cotas altimétricas, erodindo as escarpas cristalinas e depositando material na atual área emersa. Conseqüentemente, com mudanças no nível de base, a rede de drenagem passa a sofrer um rearranjo, modificando suas deposições, por conta da variação da energia de transporte. Concomitantemente aos depósitos marinhos e fluviais ocorrem também depósitos gravitacionais por meio de escorregamento de massa das escarpas da Serra do Mar. A gênese deste material ocorre pela agressiva ação intempérica atuante no Planalto Atlântico, constituindo seu manto pedológico. Este fato, associado à proximidade do Oceano e a barreira orográfica que constitui a Serra do Mar, ocasiona um intenso regime pluviométrico, acarretando em inerentes eventos de corridas de lama e escorregamentos de massa, que tem como área de deposição a Planície Sedimentar de Caraguatatuba. A compreensão e espacialização destes eventos constituem o objetivo deste trabalho que busca relacionar, na Planície Sedimentar de Caraguatatuba, os sedimentos marinhos, fluviais e gravitacionais, por sua gênese e evolução. O método de tradagens e análise de textura, assim como análises laboratoriais de amostras coletadas em trincheiras também são verificadas. Durante os estudos foram verificadas as ocorrências de materiais grosseiros próximos às escarpas cristalinas, por vezes recobertos por material argiloso, corroborando com as hipóteses levantadas. / Abstract: The Caraguatatuba's Sedimentary Plain can be considered as an exception in relation to other plains that surround it. Between the Canal de São Sebastião (SP) and Cabo Frio (RJ) predominate beaches discontinuous, segregated by indentations in the Planalto Atlântico, which sometimes suffer direct abrasion of the ocean. The beaches of the northern coast of São Paulo state and south of Rio de Janeiro state are known as "pocket beaches", presented by a plain sedimentation in small size in order to enter in some continent. However, in the Caraguatatuba's Plain, the scarped have a distance of 12 km to the current range of surf and the bay has an opening of about 10 km, unspoilt, so the other nearby plains. This fact is due to geological and structural factors, the Serra do Mar and the presence of alkaline intrusion of the São Sebastião, which allow the sedimentation in the area. This sedimentation occurs because sediment deposition by marine and / or river action. During the Quaternary period there were changes in relative sea level (glacio-eustatic variations), which showed advances and retreats of the coastline. Thus, to acquire higher levels, the marine abrasion reached certain thresholds altitude, eroding the scarped and depositing crystalline material in the current land area. Therefore, with changes in base level, the drainage network is undergoing a rearrangement, changing their statements, due to the variation of the energy transport. At the same time the marine deposits and fluvial deposits also occur through gravitational landslides of the scarped of the Serra do Mar. The genesis of this material is weathering the aggressive operating in Planalto Atlântico, making his cloak pedological. This fact, coupled with the proximity of the ocean and orographic barrier that is the Serra do Mar, causes intense rainfall, resulting in inherent in racing events and landslides, which is the deposition area of the Plain Sedimentary Caraguatatuba. The understandingans and spatialization of these events is the objective of this work that seeks to relate, in Caraguatatuba's Sedimentary Plain, marine, rivers and gravity sediments, for its genesis and evolution. The method of auger core and texture analysis, and laboratory analysis of samples collected in trenches are also checked. During the studies were verified instances of coarse material near the crystalline scarped, sometimes covered with clay-like material, which agrees with the hypotheses. / Mestrado / Análise Ambiental e Dinâmica Territorial / Mestre em Geografia

O sedimento marinho da Península Antártica representa uma área sensível a mudanças ambientais. No entanto, pouco se conhece sobre as comunidades microbianas que habitam esse ecossistema, incluindo a sua diversidade, distribuição e variações temporais. O objetivo foi determinar a estrutura das comunidades microbianas nos sedimentos marinhos da Baía do Almirantado, Ilha Rei George, Península Antártica. Sedimentos da Baía apresentam uma predominância dos Filos Proteobacteria, Firmicutes e Actinobacteria. Análise temporal revelou que comunidades microbianas em sedimentos próximos à estação Ferraz são mais estáveis quando comparadas aos sedimentos em áreas de menor atividade antrópica. No gradiente de profundidade foi observado que a estrutura de comunidade não mudou, indicando tolerância a variações de pressão hidrostática. Organismos heterotróficos dos gêneros Psychrobacter, Psychromonas e Loktanella foram os mais abundantes, sugerindo uma alta concentração de matéria orgânica disponível. O enriquecimento de culturas metanogênicas produziu até 1,70 mmol de CH4 após 120 dias de incubação. Este estudo sugere que as condições dos sedimentos favorecem organismos psicrofílicos de metabolismo heterotrófico. / Marine sediment of the Antarctic Peninsula is a susceptible area to environmental changes. However, little is known about the microbial communities inhabiting this ecosystem, including its diversity, distribution and variations over time. The aim of this study was to determine the structure of microbial communities present in marine sediments of Admiralty Bay, King George Island, on the Antarctic Peninsula. Sediments from Admiralty Bay shown a predominance of the Proteobacteria, Firmicutes, and Actinobacteria phyla. Temporal analysis revealed that microbial communities in sediment, near Ferraz station, are more stable compared to that in the sediments in areas of lower human activity. No variation on the community structure was observed in depth gradient, indicating tolerance to hydrostatic pressure variations. Heterotrophic organisms of the genera Psychrobacter, Psychromonas and Loktanella were the most abundant, suggesting a high concentration of organic matter in the sediment. Enrichment of methanogenic cultures enrichment yielded 1.70 mmol of CH4. This study suggests that conditions in sediments favoring metabolism of heterotrophic and psychrophilic organisms.

Conselho Nacional de Desenvolvimento CientÃfico e TecnolÃgico / A comparaÃÃo de metodologias de digestÃo total e parcial da fraÃÃo granulomÃtrica (<1mm) de sedimentos da plataforma continental do Cearà foi realizada para verificaÃÃo desses procedimentos sobre a interpretaÃÃo da partiÃÃo geoquÃmica dos metais no ambiente sedimentar. A determinaÃÃo final dos teores dos metais Al, Cu, Fe, Mn, Ni, Pb, V , Ti , Ba, Cr e Zn foi obtida por espectrofotometria de absorÃÃo atÃmica de chama. A anÃlise estatÃstica multivariada (Cluster Analysis) evidenciou dois grupos de suporte geoquÃmico determinantes das deposiÃÃes sedimentares. No primeiro grupo distinguiram-se metais de origem predominantemente continental Al, Fe, Mn, Cr, e Zn enquanto os elementos do segundo grupo foram Ãqueles associados à deposiÃÃo carbonÃtica marinha Ni, Pb, Ba, Cu e matÃria orgÃnica. Embora os valores absolutos sejam distintos entre as medidas realizadas apÃs os dois mÃtodos de digestÃo, nÃo houve distinÃÃo da caracterizaÃÃo geoquÃmica observada para os metais em sedimentos determinada a partir dos resultados obtidos pelos diferentes mÃtodos de digestÃo. Este resultado mostrou que a digestÃo parcial com Ãgua-rÃgia a 50% alÃm de diminuir o tempo de anÃlise, a descarga de efluente laboratorial perigoso, altamente reativo e Ãcido, permite igualmente à digestÃo total, a determinaÃÃo da caracterizaÃÃo geoquÃmica de metais em sedimentos marinhos predominantemente carbonÃticos. AlÃm disso a avaliaÃÃo do uso do (Al e Ti) como normalizadores das concentraÃÃes de metais em sedimentos costeiros foi avaliado em Ãrea vizinha e observado que a fonte continental e/ou antrÃpica (atividade portuÃria) foi distinguida em dois grupos. / A comparison of methods for total and partial digestion of the size fraction (<1mm) of sediments of the continental shelf of Cearà was performed to check these procedures on the interpretation of the partition geochemistry of metals in the sediment environment. The final determination of the levels of the metals Al, Cu, Fe, Mn, Ni, Pb, V, Ti, Ba, Cr and Zn was obtained by atomic absorption spectrophotometry in flame. A multivariate statistical analysis (cluster analysis) showed two groups of supporting geochemical determinants of sedimentary deposition. In the first group is distinguished predominantly continental origin of metals Al, Fe, Mn, Cr, and Zn as the elements of the second group were those associated with marine deposition carbonatic Ni, Pb, Ba, Cu and organic matter. Although the absolute values are different between measurements taken after the two methods of digestion, there was no distinction of Geochemical characterization observed for metals in sediment determined from the results obtained by different methods of digestion. This result showed that the partial digestion with aqua regia and 50% lower than the time of analysis, the discharge of effluent laboratory dangerous, highly reactive, acid, also allows for total digestion, the determination of the geochemical characterization of metals in marine sediments predominantly carbonates. In addition to evaluating the use of (Al and Ti) and standardized concentrations of metals in coastal sediments was evaluated in an area nearby and found that the continental source and / or anthropogenic (port activity) was distinguished into two groups.

Abstract This thesis examines the Mid-Pliocene climatic extreme ca. three million years ago (Ma) which was the latest longtime warm period. It is an important topic because the climate back then was warmer compared with the present. The bipolar regions are studied because they represent the largest areas that control the global climate. This study is based on clay mineral research that may significantly improve our knowledge of the Mid-Pliocene climate when combined with other palaeoenvironmental data. The paleoclimatological objectives of this study were: 1) to investigate how clay minerals reflect the Mid-Pliocene Global Warmth event, 2) to study ice sheet development at high latitudes, especially in East-Antarctica, and the history of ice rafting and sea ice, especially in the Arctic Ocean. This thesis deals with the clay mineral distribution and compositional analysis of the Pliocene-aged marine sediment sequences provided by the Ocean Drilling Program (ODP). The first studied site, Site 1165, is located at the continental rise of Prydz Bay, East Antarctica, and the second studied site, Site 911, is located at the Yermak Plateau, north of Svalbard, in the Arctic Ocean. The Pliocene smectite clay minerals at Site 1165 were mainly derived from Antarctic continental sources and transported to the site primarly by bottom currents related to warm events during the last 5 Ma. The evidence obtained in this study shows that the East Antarctic ice sheet may have been a dynamic ice sheet during the past 5 Ma, especially during the Mid-Pliocene. The results from the Mid-Pliocene possibly suggest a general warming trend. Based on the composition of the heavy minerals and clay minerals, at Site 911, the Pliocene smectite clay minerals were mainly transported within sea ice by the Siberian branch of the Transpolar Drift. The results indicate a warming trend at approximately 3 Ma after which they indicate a shift back to glacial conditions. Based on this study, the Mid-Pliocene Global Warmth can be observed in both the Arctic and Antarctic regions.

The purpose of the study was to examine the distributional patterns of diatoms in the surface sediments of ten southern British Columbia inlets with respect to oceanographic and hydrographic setting, and phytoplankton distribution and productivity. The study area was divided on the basis of inlet type (high, medium, and low runoff), within-inlet gradients, and zones (northern, central, and southern). A small group of species dominated the 95 sediment assemblages. There was a fairly good correlation between the biocoenoses and the thanatocoenoses in the sense that most of those species reported as dominants in the phytoplankton were also dominants in the sediment assemblages. However, there were discrepancies and these could not be explained on the basis of the relative silicification of the diatom valves. Skeletonema costatum, usually considered a weakly-silicified, dissolution-sensitive species, was abundant in British Columbia sediments. Both the pacifica and the aestivalis forms of Thalassiosira aestivalis were abundant in the phytoplankton, but only the pacifica form was preserved well in the sediments. Thalassiosira nordenskioeldii, which is found in other sediment assemblages, was rare in most British Columbia sediments. The distributional patterns of freshwater and marine littoral species appeared to be indicative of river sources entering the estuarine system. The absolute abundance of diatoms in the sediment assemblages increased from the northern to the southern zone. Within the inlets, both absolute abundance and primary productivity increased toward the mouth. Estuarine circulation did not appear to alter substantially the spatial relationship between the biocoenoses and the thanatocoenoses. In general, individual species and species-groups often exhibited distinct distributional patterns which could be related to inlet type, zonal, and within-inlet patterns. In particular, the principal coordinate analysis showed a zonal correlation between the dominant species in the sediment assemblages, and primary productivity, salinity, and temperature in the surface waters. / Science, Faculty of / Botany, Department of / Graduate