Dissertations / Theses on the topic 'Estuarine sedimentology'

Master of Science
Department of Geology
Allen W. Archer
Turnagain Arm is the hypertidal (commonly exceeding 9 m) west-east trending extension of Cook Inlet in south-central Alaska. The inlet formed from a drowned glacial valley that was subsequently filled with tidal deposits of silt and fine sand. The tidal system is semidiurnal with a prominent diurnal inequality. There are also variations due to spring and neap tides. Turnagain Arm is home to a tidal bore generated during spring tides that can reach heights of up to 2 m and travel at speeds of up to 5 m/s. Current reversals can be dramatic with ebb tidal velocities of 6 m/s changing to flood velocities of 10 m/s over a period of a few minutes. During the initial flood tide, highly turbid water can rise as fast as 10 cm/min. This combination of elements results in a highly dynamic depositional setting. Measurements taken in the inner estuary during several neap-spring cycles in the summers of 2007-08 documented deposition upon mud bars of as much as 8.9 cm per tidal event. Conversely, erosion of up to 13.5 cm per tidal event has been measured. The highest rates of deposition and erosion occurred during the spring tides while much lower rates occur during the neap tides. Some portions of the inner estuary are only submerged during the extreme high tides. The magnitude of the high tide needed to cover each site increases with increasing distance into the upper estuary. Even if submerged, deposition does not always occur. Such a high percentage of non-depositional events has real implications when interpreting tidal cyclicity of the rhythmites found at these sites.

Tide-influenced point bars represent a significant proportion of shallow-marine deposits, commonly developed along meandering channels in most backbarrier and estuarine systems. However, sedimentological studies to characterize this type of deposit are still emerging. They often present very heterogeneous internal architectures which development is controlled by the complex flow patterns operating in tidal environments. The study of the sedimentological and morphological characteristics of these features provides better understanding of the hydrodynamic processes that shape coastal systems and control their evolution as well as it contributes to better reservoir potential prediction and production strategy optimization, as tidal point bars may represent hydrocarbon reservoirs in subsurface and their heterogeneous characteristics directly impact reservoir quality. In this study, we investigated six modern tidal point bars located along distinct estuarine tidal channels in Georgia. Using core data, 2D shallow seismic data and current measurements and flow velocity profiles, we discussed the main hydrodynamic controls on sediment transport and distribution, and determined how they affect the morphology, the internal architecture and the sediment distribution within these bars. We confirmed that the influence of fluvial input in tidal channels plays an important role on the development of the morphology and the heterogeneous architecture of point bars as it adds more complexity to the system hydrodynamics, promoting more asymmetric variations in water level fluctuations and huge variations of current velocities. We proved that point bars developed in distinct tide-influenced channels and estuaries, although present very different sedimentary facies distribution, may have sedimentary facies in common, which organization is analogous to surface processes operating at each environment. We demonstrated that differences in tidal asymmetries between the ebb and flood channels produce sedimentological differences between the different parts of the bar. This study showed that tidal point bars present distinct heterogeneous sediment distributions, morphologies and internal architectures that do not conform to the existing theoretical models of fluvial point bars and highlighted that, despite the differences in local hydrodynamic conditions, similarities identified between the different bars permitted us to distinguish the sedimentological responses to regional allogenic events, which can be mistakenly interpreted as sedimentological responses to local autogenic events.

Estuarine circulation and its associated transport processes drive the environmental integrity of many near-shore habitats (the coastal ocean, rivers, estuaries and emergent wetlands). A thorough understanding and consideration of this circulation is, therefore, vital in the proper management of these habitats. The aim of this study is to bring together theory and new satellite observations in the Columbia River Estuary to increase our understanding of estuarine circulation and transport. Surface reflectance measurements gathered by the Moderate Imaging Spectroradiometer (MODIS) are first compared to in situ observations to develop an empirical model for remotely derived surface turbidity. Results indicate that MODIS data significantly correlate with in situ measurements of turbidity throughout the CRE (R2 = 0.96). Remote estimates of turbidity are then used to explore the physical processes that drive their spatial distribution. Although the response to different hydrodynamic conditions varies throughout the system, global levels of turbidity are most sensitive to fluvial and tidal inputs and increase during spring tides and high river flow. As a result, the turbidity field has temporal cycles that are consistent with the frequency of these processes. The location of the estuarine turbidity maximum (ETM) is highly dynamic and typically migrates downstream as the tidal velocity or river flow increases. The ETM becomes trapped near the Megler Bridge (river kilometer 20), however, and the presence of strong topography in this region suggests there exists an interaction between bottom topography and sediment transport. A 2-D semi-analytical model, developed herein from the simplified Navier-Stokes equations, confirms that topographic features exhibit substantial influence on longitudinal turbidity distributions. The model considers the coupled, tidally-averaged velocity (composed of gravitational circulation, internal tidal asymmetry, and river flow) and salinity fields and assumes a condition of morphodynamic equilibrium to estimate the distribution of sediment for arbitrary channel configurations. Model simulations demonstrate that topographic highs tend to increase local seaward sediment fluxes, and that topographic lows increase local landward sediment fluxes. Sediment flux convergence near topographic highs compresses the local turbidity distribution, whereas flux divergence near topographic lows dilates the distribution and, under appropriate conditions, produces multiple ETMs. In summary a combination of the model and satellite data has given valuable new insights into the sediment dynamics of estuarine environments; in particular, both show that turbidity distribution and ETM location vary considerably with tidal and river flow conditions, fluctuating on a variety of timescales, and are heavily influenced by bottom topography.

Studies of episodic shoreline accretion of the Columbia River Littoral Cell (CRLC) have been ongoing since 1964. In this study, the sediment volumes in the late Holocene barriers and beach plains are compiled and formatted in GIS compatible databases for the four sub-cells of the CRLC. Initial evaluation involved the creation of a geodatabase of 160 dated retreat scarp positions, that were identified on across-shore GPR and borehole profiles. Ten primary timelines were identified throughout the CRLC (0-4700 ybp) and those were used to develop polygon cells. Elevation, distance measurements, and position information were all linked to the polygon through a centroid location within the geodatabase. Once the geodatabase was completed, data was imported into MSAccessTM to create a relational database that would allow for examination of the littoral cell in its entirety or of the individual sub-cells. Within the database, sediment volumes, ages, accretion rates, sediment thicknesses, and timeline relationships were calculated and recorded. Using the database, the accretion history of the Columbia River Littoral Cell was evaluated and this examination illustrated the complexity of the system. Northern littoral transport was shown to be an important factor in the development of the littoral cell as a whole. Total sediment volume in the littoral cell was calculated to be 1.74 x 109 m3, with a mean accretion rate of 1.90 x 104 m3/yr, which is significantly less than some previous studies. This is due to a more detailed analysis of the beach and foredune facies themselves. This is likely the result of the higher precision of beach and foredune surface information using LiDAR. The database shows that the developmental history of the CRLC is dependent on temporal and spatial constraints that can be coupled with reverse modeling to predict shoreline erosion trends from impounded river sediments and potential global sea level rise. The North Beaches and Grayland Plains sub-cells have the greatest potential for future erosion; followed by the Clatsop Plains sub-cell.

Reliable estimates of river discharge and sediment transport to the ocean from large tidal rivers are vital for water resources management, efficient river and harbor management, navigational purposes, and climate analyses. Due to the difficulties inherent in measuring tidal-river discharge, hydrological and sedimentological records are typically too short to adequately characterize long-term (decadal) trends. Also, uncertainties associated with observation and calibration of hydrological models suggest a need for more accurate methods based on longer records of hydrodynamic parameters (e.g. tides). Tidal theory indicates that tides and river discharge interact through quadratic bed friction, which diminishes and distorts the tidal wave as discharge increases. In this study, using tidal constituents, astronomical forcing and a model of the frictional interaction of flow and tides, I propose a novel Tidal Discharge Estimate (TDE) to predict freshwater discharge with an approximate averaging interval of 18 days for time periods with tidal data but no river flow records. Next, using continuous wavelet analysis of tidal properties, I develop a method of estimating river discharge using tides measured on multiple gages along tidal rivers to improve the time-resolution and accuracy of TDE. The applicability of the Multiple-gauge Discharge Estimate (MTDE) is first demonstrated in the two largest tidal-fluvial systems of the Pacific Northwest, the Columbia River Estuary (CRE) and Fraser River Estuary (FRE). A numerical model of an idealized estuary with similar forcing as the FRE and CRE is next run under different hydrologic and morphologic scenarios to evaluate the effect of convergence, friction, and river flow variations on the applicability of MTDE. The TDE method was applied to the San Francisco Bay, using the continuous hourly tide record available since 1858. Results show that TDE reproduces known San Francisco (SF) Bay delta inflows from 1930-present with a Nash-Sutcliffe coefficient of 0.81 and is a useful method for hindcasting historical flows from 1858 - 1929, a period that predates direct measurement of delta discharge. I also recover and digitize ~80 years of Sacramento River daily water level data between 1849 and 1946, from which river discharge to SF Bay is estimated on a daily basis, after adjusting for changes to the river channel. This discharge combined with Net Delta Outflow Index estimates (1930 - 2011) and flow estimates from tidal data (1858 - 2011) provides a more accurate version of SF Bay historic daily inflows from 1849 - 2011. Next, the history of sediment transport and discharge into SF Bay from 1849-present is reevaluated using the daily discharge estimates. A non-stationary rating curve between river flow and sediment transport is developed, with net sedimentation observed during five bathymetric surveys that were used to constrain the total integrated sediment discharge. Results show that ~1600±320 million-tons of sediment have been delivered to SF Bay between 1850 and 2011. There has been an approximately 25 - 30% reduction of annual flow since the 19th century, along with decreased sediment supply. This has resulted in a ~60% reduction in annual sediment delivery to SF Bay. The annual hydrograph of inflow to SF Bay and the seasonality of sediment flux have changed considerably over time, due to both human alteration and climate change. Significant historic spring-melt peak floods have disappeared in the modern system and now peak flows mostly occur in winter. My flow estimation methods also confirm that the flood of January 1862 had the largest daily sediment load and the second largest daily discharge since 1849.

Este estudo foi desenvolvido na região estuarina do rio Paraguaçu, caracterizada por um sistema transicional de influências fluvial, controlada pela descarga da barragem de Pedra do Cavalo, e marinha, proveniente das águas da baía de Todos os Santos. Com o objetivo de verificar a distribuição e o comportamento geoquímico do Cu, Cd, Pb, Cr, Zn, Fe, Al e Mn no material particulado em suspensão e nos sedimentos de fundo, quinze pontos de amostragem foram investigados ao longo do complexo estuarino, durante oito campanhas planejadas, entre o período 1994-1995, de acordo com a sazonalidade e a dinâmica das marés de sizígia e quadratura. Um ponto fixo foi monitorado para o material particulado em suspensão e parâmetros físico-químicos associados, durante doze horas, em diferentes ciclos de marés enchente e vazante. Os resultados sugerem que a distribuição dos metais é influenciada pelos efluentes locais e dinâmica das marés. Durante as marés de sizígia os metais são importados da baía de Todos os Santos, junto ao material particulado em suspensão que entra no sistema estuarino. O sedimento de fundo parece estar atuando como reservatório semi-permanente e acumulador de metais no ecossistema. Também nas marés de sizígia, o material fino do sedimento é ressuspenso e incorporado ao material particulado em suspensão, presente na coluna d\'água. As variações não são significantes, conforme os fluxos e refluxos diários da maré. O processo de acumulação resulta em concentrações particularmente elevadas de metais, que se encontram no sedimento de fundo sob formas pouco disponíveis para a biota aquática. Os valores mais altos de Cu, Zn, Cr e Fe são encontrados próximos as cidades de Cachoeira e São Félix e de Cu, Cd, Pb, Zn, Cr, Fe e Mn na foz do rio na baía de Todos os Santos, o que sinaliza a influência das ações antrópicas nestas áreas. Considerando-se a hidrodinâmica do sistema, a metodologia usada mostra-se adequada para o monitoramento de zonas estuarinas em ambientes tropicais. Os valores médios registrados para o ano de 1995, são referências importantes para acompanhar as mudanças produzidas por um aumento na contaminação.
This present study was carried out on Paraguaçu River estuarine área. This area is characterized by having a transitional system of fluvial and marine influences, controlled by discharges come from both Pedra do Cavalo dam and waters from Todos os Santos Bay. Fifteen sampling sites along the estuarine complex were investigated on eight planned campaigns between 1994 and 1995, in order to verify the distribution and geochemical behavior of Cu, Cd, Pb, Cr, Zn, Fe, Al, Mn considering seasonably and dynamics of spring and neap tides. One specific site was monitored for suspended particulate material as well as physical-chemical parameters during twelve hours covering different cycles of flood and ebb tide. Results indicate that distribution of metals is influenced by local waste and tide dynamics. Metals are imported from Todos os Santos Bay during spring tide along with suspended particulate material flushed into the estuarine system. The bottom sediment apparently acts as a semi-permanent reservoir, accumulating metals in the eco-system. Also, during spring tide, the sediment\'s fine material is re-suspended and therefore incorporates the suspended particulate material floating in the water. Variations due to daily changes in the flow of tides are not significant. The accumulation process results in particularly high concentrations of metals lying in bottom sediments under circumstances which make them hardly available for the aquatic biota. Highest values of Cu, Zn, Cr, Fe were found at sites closest to cities of Cachoeira and São Felix while highest values of Cu, Cd, Pb, Zn, Cr, Fe, Mn were found by the mouth of the river at Todos os Santos Bay, indicating these areas are influenced by surrounding antropogenic activity. Considering the system\'s hydro-dynamics, the methodology applied proves itself adequate for monitoring estuarine zones in tropical environments. Average values registered during the year of 1995 are important references in order to understand changes produced by increase in contamination.

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O estuário do rio Timbó está localizado na praia de Maria Farinha, Pernambuco, abrangendo uma área de quase 1 400ha. Visando preencher uma lacuna de conhecimento sobre aspectos sedimentológicos desta zona estuarina, análises texturais, granulométricas, morfoscópicas e cálculo de parâmetros estatísticos foram realizados em 46 pontos de amostragem, em transectos de uma margem à outra. Estas análises subsidiaram a elaboração de mapas temáticos. A fração areia prepondera, com maiores concentrações na desembocadura e nas áreas de deságüe dos arroios Desterro e da Fábrica. Resultados platicúrticos e muito platicúrticos são observados no estuário médio e sudeste do estuário superior, indicando áreas de moderada energia e menor grau de seleção. Os valores leptocúrticos a muito leptocúrticos prevalecem no inferior sugerindo maior atuação de energia, apesar de os sedimentos não se apresentarem bem selecionados. As amostras revelaram assimetria desde muito negativa a muito positiva, indicando mistura de sedimentos de diversas fontes, e vários processos geológicohidrodinâmicos contribuindo na configuração dos depósitos sedimentares. Apresentam quartzo transparente, subanguloso a anguloso, com esfericidade de baixa à média. Os componentes biogênicos são representados por foraminíferos bentônicos, planctônicos marinhos, ostracodes mixohalinos, fragmentos de biválvios, gastrópodos, espinhos rolados de equinóides marinhos e restos lenhosos. As características ambientais do estuário do rio Timbó têm aspectos de grande potencial. As informações sedimentológicas adquiridas poderão auxiliar na adequada gestão ambiental do ecossistema, e fundamentar estudos sobre sua gênese e evolução

Orientador: Mario Luis Assine
Banca: Rosemarie Rohn Davies
Banca: Almério Barros França
Resumo: A Formação Rio Bonito é a unidade inferior do Grupo Guatá, Eopermiana da Bacia do Paraná. Compreende, da base para o topo, os membros Triunfo, Paraguaçu e Siderópolis. No Estado do Paraná, a espessura da Formação Rio Bonito diminui para norte, principalmente em conseqüência do adelgaçamento e acunhamento do Membro Triunfo, que desaparece no sul do Estado de São Paulo. Para investigar estas variações de espessura e de fácies na Formação Rio Bonito, foi escolhida uma área no nordeste do Estado do Paraná onde a unidade apresenta bons afloramentos e poços para correlação, além de existirem importantes ocorrências de carvão. Para atingir os objetivos propostos, foram levantados perfis estratigráficos verticais e confeccionadas seções estratigráficas, levantados dados de paleocorrentes, caracterizadas associações de fácies sedimentares, correlacionados dados de superfície com os de perfis de poços, interpretados os paleoambientes de sedimentação e comparado o empilhamento estratigráfico da área estudada com o de áreas adjacentes. Cinco associações de fácies foram caracterizadas, permitindo constatar que a parte inferior da Formação Rio Bonito no nordeste do Estado do Paraná apresenta espessuras variáveis por ser o produto de preenchimento sedimentar uma sobre superfície deposicional irregular. Devido à existência de paleovales na superfície do topo do Grupo Itararé, de estruturas sedimentares produzidas por correntes de maré e de paleocorrentes bipolares para norte e sul, a parte inferior da Formação Rio Bonito foi interpretada como produto de preenchimento de vales incisos por depósitos aluviais e de canais de maré (associações de fácies 1 e 2, Membro Triunfo), sobrepostos retrogradacionalmente por lamitos e arenitos de canais de maré da zona central do estuário (associação de fácies 3)...(Resumo completo, clicar acesso eletrônico abaixo)
Abstract: The Rio Bonito Formation is the lowermost unit of the Guatá Group, Early Permian of the Paraná Basin. It comprises from the bottom to the top, the Triunfo, Paraguaçu and Siderópolis Members. In the State of Paraná, the thickness of the Rio Bonito Formation decreases northwards, mainly because of the thinning and wedging out of the Triunfo Member, which disappears in the south of the State of São Paulo. To investigate thickness and facies variations in the Rio Bonito Formation, an area in the northeast of the State of Paraná was chosen wherein the unit presents good outcrops and wells for correlation, besides the existence of important coal beds. To reach the proposed objectives, vertical stratigraphic profiles and stratigraphic sections were made, paleocurrents data were obtainded, sedimentary facies were characterized, correlation between surface and well profile data were performed, sedimentation paleoenvironments were interpreted and the local stratigraphic succession correlated with adjacent areas. Five facies associations were characterized, being possible to observe that the thickness variations of the Rio Bonito Formation in the northeast of the State of Paraná resulted from sedimentation on an irregular depositional surface. Due to the existence of paleovalleys and the sedimentary structures produced by tide currents and bipolar paleocurrents towards the north and south, the lower portion of the Rio Bonito Formation was interpreted as a product of incised-valleys filled-up by estuarine alluvial and tidal channels deposits (facies associations 1 and 2, Triunfo Member). The succession is retrogradational and the basal section is overlayed by mudstones and sandstones of tidal-channels from the innermost portion of the estuary (facies association 3)...(Complete abstract click electronic access below)
Mestre

MIOLA, B. Proveniência de sedimentos para os ecossistemas estuarinos do litoral Oeste do Ceará. 2017. 166 f. Tese (Doutorado em Ciências Marinhas Tropicais) - Universidade Federal do Ceará, Instituto de Ciências do Mar. Fortaleza, 2017.
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Estuaries are ecosystems that present their formation related to the relative flutuations of the quaternary sea level, being the sedimentary records that occur in these environments of relevance for studies related to current sea level and towards the mean sea level rise itself. The fine sediments of different origin can be distinguished by their associations of clay minerals, as they can serve as tracers for sediment pathways, even over long distances. Based on granulometric, mineralogical and geochemical analysis, the present study aims at evidencing sediment sources and filling the estuaries of the Acaraú and Coreaú rivers, in addition, correlating the clay minerals and geochemical carriers as a proxy for pollutants identification for the estuarine environment. In both estuaries, the clay mineralogical assembly is composed predominantly of kaolinite, illite and smectite. There are also minerals accessories such as: quartz, rutile, pyrite, lepdocrocite and calcite. Surface samples and sediment cores collected in the Acaraú estuary show that the estuary is predominantly filled by marine sediments. In the Coreaú estuary the influence of marine sediments is observed in very great distances of the mouth of the river. In both estuaries, the great contribution of marine sediments occurs due to the lack of entrance of fluvial sediments because the climatic characteristics in the region, besides the influence of the anthropic activities like the dams. Regarding the distribution of the main geochemical pollutants carriers in the Acaraú estuary, a distribution was correlated with the use and occupation of the soil in the estuary. With the results obtained, it is concluded that the climate is one of the most important controlling variables of the sediment sources for the estuaries in the west coast of the Ceará state.
Os estuários são ecossistemas que apresentam suas formações relacionadas com as flutuações relativas do nível do mar Quaternário, sendo os registros sedimentares que ocorrem nesses ambientes de relevância tanto para estudos relacionados ao nível do mar atual como no sentido da própria subida de nível médio do mar. Os sedimentos finos de diferente origem podem ser distinguidos pelas suas associações de argilominerais, que funcionam como uma espécie de impressão digital que permite traçar sua via de transporte inclusive em longas distâncias. Baseado em análises granulométricas, mineralógicas e geoquímicas, o presente estudo visa evidenciar as fontes de sedimentos e o preenchimento dos estuários dos rios Acaraú e Coreaú, além de correlacionar os argilominerais e carreadores geoquímicos como proxy de identificação de poluentes para o ambiente estuarino . Em ambos os estuários estudados, a assembleia mineralógica de argilominerais é composta predominantemente por caulinita, ilita e esmectita. São encontrados também minerais acessórios como: quartzo, rutilo, pirita, lepidocrocita e calcita. As amostras superficiais e testemunhos sedimentares coletados no estuário do rio Acaraú mostram que o estuário é preenchido predominantemente por sedimentos marinhos. No estuário do rio Coreaú observa-se a influência de sedimentos marinhos em distâncias muito grandes da foz do rio. Em ambos os estuários, o grande aporte de sedimentos marinhos ocorre devido a falta de entrada de sedimentos fluviais por causa das características climáticas na região, além da influência das atividades antrópicas como a construção de barragens. Com relação à distribuição dos principais carreadores geoquímicos de poluentes no estuário do Acaraú, observou-se uma distribuição correlacionada com o uso e ocupação do solo no estuário. Com os resultados aqui obtidos, conclui-se que o clima constitui uma das mais importantes variáveis controladoras das fontes de sedimentos e para os estuários no litoral oeste do estado do Ceará.

Cerca de dois terços das maiores áreas metropolitanas mundiais estão nas proximidades dos estuários, portanto são regiões comumente sujeitas à situações de risco impostas pela pressão populacional. Instalações portuárias, efluentes diversos, uso indevido das suas margens, estão entre os riscos potenciais à grande diversidade de seus recursos naturais. A ação das marés, das ondas e o aporte fluvial interagem tornando bastante complexa a caracterização do seu funcionamento. A presente dissertação foca os seguintes aspectos: hidrodinâmica, transporte de sedimentos em suspensão, sedimentologia, morfologia e classificação do ambiente. A hidrodinâmica e o transporte de sedimentos foram estudados em duas etapas de campo em condições de maré de sizígia e de quadratura, cada qual com abrangência de dois ciclos de maré (25 hs). Estas etapas foram realizadas numa estação fixa com medições de: maré, velocidade da corrente, material em suspensão, sólidos totais dissolvidos, salinidade, pH, oxigênio dissolvido e temperatura. As características sedimentológicas foram avaliadas pela coleta de sedimentos de fundo em 24 pontos. Os aspectos morfológicos foram reconhecidos por uma batimetria detalhada e por aerofotografias. Os resultados revelaram a dominância das correntes de maré vazante em sizígia e de enchente em quadratura. O fluxo total de sedimentos por ciclo de maré na sizígia foi de 71 ton. (vazante), enquanto que na quadratura foi de 2,2 ton. (enchente). Os sedimentos de fundo variaram de areia muito grossa a silte. A profundidade máxima foi de 7,4 m (maré alta de sizígia). A comparação das aerofotografias revela a instabilidade morfológica da desembocadura. Relaciona-se este fato à influência variável da deriva litorânea e da descarga hidráulica. Este estuário foi classificado como: de frente de barreira arenosa; de circulação do tipo xvi parcialmente misturada e, por vezes, verticalmente homogênea; de Tipo 2b (quadratura); de tipo intermerdiário 2a e 2b (sizígia); de negativo; de mesomaré e de energia mista.

Neste trabalho foram estabelecidos os níveis basais de concentração de metais nos sedimentos do sistema estuarino da Baixada Santista. O local da área de estudo foi o Canal de Bertioga que apresentou as seguintes concentrações basais: Ag (<1,00 mg.kg-1), Al (27.213 mg.kg-1), As (9,84 mg.kg-1), B (90,1 mg.kg-1), Ba (26,2 mg.kg-1), Be (<0,03 mg.kg-1), Cd (<0,02 mg.kg-1), Co (6,70 mg.kg-1), Cr (27,8 mg.kg-1), Cu (11,0 mg.kg-1), Fe (31.954 mg.kg-1), Hg (<0,02 mg.kg-1), Mn (299 mg.kg-1), Mo (<4,00 mg.kg-1), Ni (11,2 mg.kg-1), Pb (<0,26 mg.kg-1), Sb (<1,10 mg.kg-1), Se (<0,20 mg.kg-1), Sn (<5,00 mg.kg-1), Ti (336 mg.kg-1), Tl (<2,30 mg.kg-1), V (37,3 mg.kg-1) e Zn (63,8 mg.kg-1), onde o As foi o elemento que apresentou concentrações mais elevadas em comparação com a Resolução CONAMA Nº 344/04. No estudo realizado para avaliar a distribuição das concentrações de metais em duas diferentes frações granulométricas (<2,00 mm e <63 µm), mostrou que na maioria dos casos a fração mais fina (<63µm ) incorpora mais metais que a fração total (<2,00 mm) e a fração granulométrica mais adequada para determinação de metais em amostras de sedimentos para a maioria dos estudos ambientais é a fração <2,00 mm. Para avaliar e comparar métodos de solubilização de amostras de sedimentos para determinação de metais por técnicas espectrométricas, três diferentes métodos foram utilizados, sendo dois com solubilização parcial da amostra de sedimento (U.S EPA 3051a, com HNO3 e HNO3 + HCl) e um terceiro com solubilização total (U.S EPA 3052, com HNO3 + HCl + HF), os resultados mostraram que ambos os métodos da U.S EPA 3051a são estatisticamente equivalentes e a solubilização pelo método U.S EPA 3052 apresentou concentrações mais altas em relação aos valores obtidos na solubilização parcial para a maioria dos metais. Outro objetivo deste trabalho foi testar e avaliar duas técnicas para determinação de granulometria, com ao menos um método conservativo, mostrando que os dois métodos são estatisticamente equivalentes, porém o método conservativo não foi adequado para estimar a fração orgânica. No estudo para estimar e avaliar as concentrações de metais em ostras, mostrou que as concentrações de As, Cd, Cu, Hg, Ni, Pb, Sb, Sn e Se apresentaram-se abaixo dos níveis estabelecidos pela ANVISA, enquanto que para o Zn os valores estiveram acima do valor estabelecido pela ANVISA, mas em concordância com níveis encontrados em outros estudos ambientais.
In this work were established the background concentrations of metals in sediments of Estuarine System of Baixada Santista. The location of study area was the Canal de Bertioga which presented the following basal concentrations: Ag (<1,00 mg.kg-1), Al (27.213mg.kg-1 ), As (9,84 mg.kg-1), B (90,1 mg.kg-1), Ba (26,2 mg.kg-1), Be (<0,03 mg.kg-1), Cd (<0,02 mg.kg-1), Co (6,70 mg.kg-1), Cr (27,8 mg.kg-1), Cu (11,0 mg.kg-1 ), Fe (31.954 mg.kg-1 ), Hg (<0,02 mg.kg-1), Mn (299 mg.kg-1), Mo (<4,00 mg.kg-1), Ni (11,2 mg.kg-1), Pb (<0,26 mg.kg-1), Sb (<1,10 mg.kg-1), Se (<0,20 mg.kg-1), Sn (<5,00 mg.kg-1), Ti (336 mg.kg-1), Tl (<2,30 mg.kg-1), V (37,3 mg.kg-1) and Zn (63,8 mg.kg-1), where As was the element that presented high concentrations incomparison to Resolucao CONAMA Nº 344/04 (Brazilian Guidelines). In the study to evaluate the distribution of metals concentrations in two different size fractions (<2,00 mm and <63µm), showed that in most of the cases that the finest fraction (<63µm) can incorporate much more metals than total fraction (<2,00 mm) and the most adequate fraction for determination of metals in sediments samples in the majority of environmental studies is <2,00 mm. In order to evaluate and compare methods of solubilization of sediments samples for determination of metals by spectrometry techniques were used three different methods, two for total-recoverable concentrations (U.S EPA 3051a, com HNO3 e HNO3 + HCl) and a third one for total-total concentrations (U.S EPA 3052, com HNO3 + HCl + HF), the results showed that both U.S 3051a methods are statistically similar and U.S EPA 3052 method presented higher concentrations in relation to U.S 3051a method for the huge majority of metals. Another objective of this work was to test and evaluate two methods for determination of particle size with at least one method without destruction of organic matter called sieving and the results showed that sieving method wasn\'t adequate to estimate organic matter fraction (<20 µm). In the study to estimate and evaluate metals concentrations in oyster tissue showed that As, Cd, Cr, Cu, Hg, Ni, Pb, Sb, Sn and Se presented values lower than the levels established by ANVISA while Zn presented higher values but in according to levels found in other environmental studies.

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Agência Nacional do Petróleo, Gás Natural e Biocombustíveis (ANP)
A Formação Rio Bonito é a unidade inferior do Grupo Guatá, Eopermiana da Bacia do Paraná. Compreende, da base para o topo, os membros Triunfo, Paraguaçu e Siderópolis. No Estado do Paraná, a espessura da Formação Rio Bonito diminui para norte, principalmente em conseqüência do adelgaçamento e acunhamento do Membro Triunfo, que desaparece no sul do Estado de São Paulo. Para investigar estas variações de espessura e de fácies na Formação Rio Bonito, foi escolhida uma área no nordeste do Estado do Paraná onde a unidade apresenta bons afloramentos e poços para correlação, além de existirem importantes ocorrências de carvão. Para atingir os objetivos propostos, foram levantados perfis estratigráficos verticais e confeccionadas seções estratigráficas, levantados dados de paleocorrentes, caracterizadas associações de fácies sedimentares, correlacionados dados de superfície com os de perfis de poços, interpretados os paleoambientes de sedimentação e comparado o empilhamento estratigráfico da área estudada com o de áreas adjacentes. Cinco associações de fácies foram caracterizadas, permitindo constatar que a parte inferior da Formação Rio Bonito no nordeste do Estado do Paraná apresenta espessuras variáveis por ser o produto de preenchimento sedimentar uma sobre superfície deposicional irregular. Devido à existência de paleovales na superfície do topo do Grupo Itararé, de estruturas sedimentares produzidas por correntes de maré e de paleocorrentes bipolares para norte e sul, a parte inferior da Formação Rio Bonito foi interpretada como produto de preenchimento de vales incisos por depósitos aluviais e de canais de maré (associações de fácies 1 e 2, Membro Triunfo), sobrepostos retrogradacionalmente por lamitos e arenitos de canais de maré da zona central do estuário (associação de fácies 3)...
The Rio Bonito Formation is the lowermost unit of the Guatá Group, Early Permian of the Paraná Basin. It comprises from the bottom to the top, the Triunfo, Paraguaçu and Siderópolis Members. In the State of Paraná, the thickness of the Rio Bonito Formation decreases northwards, mainly because of the thinning and wedging out of the Triunfo Member, which disappears in the south of the State of São Paulo. To investigate thickness and facies variations in the Rio Bonito Formation, an area in the northeast of the State of Paraná was chosen wherein the unit presents good outcrops and wells for correlation, besides the existence of important coal beds. To reach the proposed objectives, vertical stratigraphic profiles and stratigraphic sections were made, paleocurrents data were obtainded, sedimentary facies were characterized, correlation between surface and well profile data were performed, sedimentation paleoenvironments were interpreted and the local stratigraphic succession correlated with adjacent areas. Five facies associations were characterized, being possible to observe that the thickness variations of the Rio Bonito Formation in the northeast of the State of Paraná resulted from sedimentation on an irregular depositional surface. Due to the existence of paleovalleys and the sedimentary structures produced by tide currents and bipolar paleocurrents towards the north and south, the lower portion of the Rio Bonito Formation was interpreted as a product of incised-valleys filled-up by estuarine alluvial and tidal channels deposits (facies associations 1 and 2, Triunfo Member). The succession is retrogradational and the basal section is overlayed by mudstones and sandstones of tidal-channels from the innermost portion of the estuary (facies association 3)...(Complete abstract click electronic access below)

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Conselho Nacional de Desenvolvimento Científico e Tecnológico
O estuário do Rio Formoso, localizado no litoral sul do Estado de Pernambuco (UTM 9036000 / 266000; 9044.000 / 272000), esta inserido na Área de Proteção Ambiental de Guadalupe. É um importante ecossistema costeiro tanto pela biodiversidade como para o turismo. Informações existentes sobre este estuário concentravam-se em aspectos biológicos, carecendo de pesquisas abordando o quadro físico de forma integrada. Visando preencher esta lacuna, e fornecer subsídios para ações de gestão ambiental, foram realizados estudos aplicando métodos diretos e indiretos, enfocando a sedimentologia, a geofísica estuarina, a morfodinâmica e os aspectos da qualidade da água que possibilitaram tecer considerações sobre o quadro fisico. A partir da elaboração do mapa batimétrico, a área foi subdividida, em setores superior, médio e inferior. Nos três Setores, foram realizados estudos da sedimentologia de fundo e da qualidade da água. Apenas no Setor Inferior, foram feitos o imageamento por sonar de varredura e a morfodinâmica praial (incluindo a praia de Guadalupe). Como resultado, foi identificado que no Setor Superior predominam cotas batimétricas de 1m, leito constituído por areia lamosa, lama arenosa e lama (silte-argila). No Setor Médio, a batimetria tem em média de 3m, sendo indentificado um trecho mais profundo (> 5m), na margem direita com dominância das fácies areia, areia cascalhosa, areia lamosa e, associada ao substrato do manguezal, lama arenosa. No Inferior, com profundidade média de 4m e presença de cascalhos concentrados no canal localizado na margem esquerda. Formas de fundo identificadas, por sonar de varredura, representadas por dunas subaquosas assimétricas de cristas sinuosas e simétricas de cristas retas bifurcadas, indicando grande influência de marés e ondas, representando condições hidrodinâmicas típicas de regime de fluxo inferior. A diferença entre os estoques de sedimentos arenosos dos perfis medidos, ao longo da praia de Guadalupe, sugere déficit indicando comportamento erosivo, típico de praias reflectivas. A praia dos Carneiros apresenta características dissipativas, com exposição de bancos arenosos longitudinais durante a maré vazante. Na margem esquerda do estuário, o trecho da praia de Guadalupe termina de forma abrupta no canal adjacente correspondente ao trecho de maior energia hidrodinâmica. Com base na análise de alguns parâmetros bio-químicos e físico-quimícos, foi observado que a qualidade da água do Rio Formoso estava comprometida e imprópria à balneabilidade, por apresentar altas concentrações de coliformes fecais, indicando contaminação/poluição, por lançamentos de esgotos domésticos. Como produtos destes estudos, foram gerados mapas temáticos e referenciais técnicos importantes para o planejamento da gestão ambiental, para futuras ações de conservação/recuperação das condições ambientais, medidas de saneamento mais efetivas e manutenção das atividades sócio-economicas da área

Tese de doutoramento, Geologia (Geoquímica), Universidade de Lisboa, Faculdade de Ciências, 2016
A presente dissertação foca‐se essencialmente no estudo sedimentológico e geoquímico de sedimentos intermareais do estuário do Sado a diferentes escalas temporais – abordagem à micro‐ e mesoescala temporal. A reconstrução da variação dos teores elementares ao longo de quatro colunas sedimentares curtas, das principais áreas intermareais do estuário em estudo, possibilitou a identificação das condições locais/regionais pristinas de metais relacionados com problemas de cariz ambiental, assim como o início e evolução da influência antrópica nestes ambientes. Os valores de fundo geoquímico em Cu, Zn e Pb para os sedimentos do estuário inferior são 37 – 46, 67 – 154 e 15 – 43 mg kg ‐1, respectivamente, diferenciando‐se dos obtidos para o estuário superior; todavia, a ocorrência de processos diagenéticos na coluna sedimentar mais a montante não permite garantir que correspondam a valores pristinos (ou pré‐industriais). Com excepção do Pb no Sapal da Carrasqueira, a camada superficial das colunas sedimentares do estuário inferior apresenta contaminação nos três metais (Factores de Enriquecimento até ~6). A caracterização físico‐quimica, textural e composicional dos sedimentos actuais dos Sapais de Alcácer do Sal, Faralhão, Carrasqueira e Malha da Costa, principais áreas intermareais existentes ao longo do estuário do Sado, demonstra que embora de um modo geral não se verifique a ocorrência de sazonalidade, entre o Outono de 2005 e a Primavera de 2006, dos parâmetros sedimentológicos e geoquímicos analisados, existe uma variabilidade espacial evidente do Cr, Ni, Cu, Zn e Pb como reflexo de fontes antropogénicas distintas ao longo do estuário e do comportamento físico‐químico ao longo deste sistema estuarino na dispersão de metais com fonte na bacia hidrográfica. Os sedimentos dos ambientes intermareais do estuário inferior tendem a exibir contaminação em Cu, Zn e Pb, e só pontualmente os Factores de Enriquecimento são superiores a 6. Um estudo complementar em sedimentos superficiais do estuário do Sado (Sapal do Faralhão) e do Tejo (Sapal do Rosário e raso de maré distal das Hortas) indica, com base na análise geoquímica elementar (padrões de distribuição de Terras Raras e Índice de Alteração Química) e isotópica em Sr e Nd, que os sedimentos resultam da meteorização moderada da rocha‐mãe. O estudo geoquímico elementar e isotópico de Spartina maritima e Scrobicularia plana indica a ocorrência de fracionamento geoquímico significativo entre os seus tecidos e o sedimento que colonizam, ocorrendo a bioacumulação de vários elementos em tecidos específicos; e embora a água marinha exerça influência, o principal mecanismo de fracionamento deve estar relacionado com a biodisponibilidade elementar para processos metabólicos específicos.
This thesis focuses mainly on the sedimentological and geochemical study of intertidal sediments of the Sado estuary at different time scales ‐ at micro‐ and mesoscale. The variation of the elemental contents along four short cores, from the main intertidal estuarine areas, allowed the identification of the local/regional pristine contents of metals related with environmental issues, as well as the beginning and evolution of the anthropic influence on these environments. In the lower estuary the geochemical background of Cu, Zn and Pb is 37‐46, 67‐154 and 15‐43 mg kg ‐1, respectively, differing from those obtained for the upper estuary. However, the occurrence of diagenetic processes in the most upstream sedimentary column does not allowed to ensure that its values correspond to pristine (or pre‐industrial) values. With the exception of Pb in Sapal da Carrasqueira, the superficial layer of the sedimentary columns from the lower estuary is contaminated by the three metals (Enrichment Factors up to ~ 6). The physico‐chemical, textural and compositional characterization of the recent sediments from the marshes of Alcácer do Sal, Faralhão, Carrasqueira and Malha da Costa, the main intertidal areas along the Estuary of Sado, demonstrate that, in a general way, there is no seasonal variability of the sedimentological and geochemical parameters analyzed. Nevertheless, there is a clear spatial variability of Cr, Ni, Cu, Zn and Pb as reflex of distinct anthropogenic sources along the estuary and of the physico‐chemical behavior throughout this estuarine system in the dispersion of metals sourced in the watershed. The intertidal sediments tend to exhibit contamination in Cu, Zn and Pb, and only occasionally enrichment factors are higher than 6. A complementary study with superficial sediments from Sado (Faralhão Marsh) and Tagus (Rosário Marsh and distal tidal flat from Sítio das Hortas), based on elemental (Chemical Index of Alteration and Rare Earth Elements distribution patterns) and isotopic (87Sr/86Sr and 143Nd/144Nd) geochemical analysis, indicates that the sediments results from moderate weathering of the bedrock. The elemental and isotopic geochemical study of Spartina maritima and Scrobicularia plana demonstrate the occurrence of significant geochemical fractionation between their tissues and sediment that each specie colonize. There is bioaccumulation of various elements in specific tissues; and although the sea water exerts influence, the main fractionation mechanism must be related to the elementary bioavailability for specific metabolic processes.

Estuaries are dynamic features of a coastline whose sediments are influenced by riverine and marine processes. Periodic events such as floods, as well as variations in mouth status, greatly affect the energy levels within an estuary and subsequently the amount of sediment erosion and deposition that takes place. Concurrently, pollutants are transported and deposited into estuaries and can reside in the sediments for many years. The estuaries of the eThekwini Municipality in KwaZulu-Natal, South Africa, are exposed to a variety of pollutants; however with the expanding industrial sector within this region, metal contamination is of concern. This study investigates the sedimentology and geochemical variations of six estuaries within the municipality namely, the uTongati, uMdloti, uMgeni, Isipingo and uMbokodweni estuaries as well as the Durban Harbour. To determine the spatial variations in estuarine sedimentology, sediment cores were collected longitudinal to the estuary axis. The core samples were analysed for sediment colour, texture and organic matter content. To assess the geochemical variations, core samples were analysed for Zn, Cu, Cr, Ni, Pb, As, Fe, Al, Ca, S, P, Mg, Mn, Cd and V concentrations. Some samples were also carbon dated to provide a temporal aspect to the sediment and geochemical variations. Descriptive and graphic techniques were used to examine the sedimentology within the estuaries; and the geochemical data was analysed with the use of multivariate statistics. Additionally, pollution indices and sediment quality guidelines were utilized to assess the pollution levels within the sediments. The results indicated that lower energy environments caused by protracted mouth closures in the uMdloti and Isipingo estuaries accounted for large amassing of fines. In contrast, the accumulation of mixed coarse and fine sediments in the uTongati and uMgeni estuaries was an indication of high fluvial flows and open mouth conditions. All carbon dated ages for all estuaries were greater than 700 years which may be attributed to a combination of scouring effects from past and recent flood events and also possibly due to the deposition of re-worked older sediments from upstream. Low metal concentrations were found within the sediments of all estuaries, and the presence of fines and organic matter governed their concentration variations with depth. The uMgeni and uMbokodweni estuaries which are located immediately downstream of industrial and urban areas, were found to contain relatively higher concentrations of elements Pb, Cu, As and Ni. These metals showed high enrichment within the sediments; however actual concentrations were below sediment quality guideline levels. General pollution levels within all estuaries were very low, and can be attributed to the climatic influences within this region which has a ‘cleansing’ effect on the estuarine environments in removing contaminants.
Thesis (M.Sc.)-University of KwaZulu-Natal, Durban, 2014.

Bottom sediments of the Upper Barataria Basin and the Mississippi River-Gulf Outlet estuarine complexes consist predominantly of silty clays and clayey silts derived from the erosion of the St. Bernard lobe of the Mississippi River delta. Montmorillonite dominates the sediment clay mineralogy and reflects the influence of the Mississippi River Basin The acid-leachable concentrations of fourteen trace metals were determined for 284 bottom sediment and 44 core interval samples by plasma emission. The areal metal distribution is controlled predominantly by the bottom sediment texture and mineralogy and is significantly correlated with smaller grain-size sediments, carbon content, and aluminum and iron content. Ba, Cd, Pb, and Zn are the least correlatable and may reflect the greatest anthropogenic influence. Sediments have greater mean metal content than Florida and Texas estuarine sediments, generally due to their finer grain size, lack of CaCO3, and higher clay, iron, and carbon content Concentrations of As, Ba, Cd, Pb, V and Zn, elevated relative to basinwide means, were detected from sediments associated with oil and gas drilling and production, sandblasting, dredging, and stormwater and industrial discharges. Average metal contents were comparable to other Gulf Coast estuaries and below the lowest effect level sediment quality guidelines from compiled biological assessments. Biological effects from metal concentrations comparable to those found would be expected to be rare Elutriate testing designed to simulate sediment disruptions similar to dredging operations or major storm events were performed on the most highly contaminated sediments. Results indicate the release of metals into the water column, but at concentrations below the Louisiana Ambient Water Quality Criteria. Sediments displayed an inherent capacity to remove the released metals from the water column upon return to original conditions Sediment accumulation rates were determined from four cores using 210Pb geochronology. Compaction corrected accumulation rates varied from 0.1 to 0.28 cm/yr and were comparable to observed rates from Louisiana estuaries. Within Lake Salvador core intervals, concentrations of As, Ba, Cr, Cd, Pb, and Zn have increased by 10% to 30% in sediments accumulated within the last 50 years, though little variation was noted from sediments accumulated during the 1800's
acase@tulane.edu