Thesis: Ph. D., Massachusetts Institute of Technology, Department of Civil Engineering, 1981 / Bibliography: leaves 264-269. / by John Jay Shaw. / Ph. D. / Ph. D. Massachusetts Institute of Technology, Department of Civil Engineering

published_or_final_version / abstract / Civil Engineering / Doctoral / Doctor of Philosophy

The San Andres Formation (Permian, Guadalupian) is the most prolific oil reservoir in the Permian basin. However, despite more than 60 years of production, an estimated 70% of the original oil in place remains. Recovery of this huge resource requires a better understanding of facies and reservoir framework, which, in turn, must be accomplished using a rock-based reservoir characterization process. This high resolution correlation method is essential for understanding the complex heterogeneities found in shallow water platform carbonates. Steps in the construction of a rock-based reservoir model in the Fullerton San Andres Unit (FSAU) included (1) defining depositional facies and primary facies groups; (2) creating an outcrop depositional model; (3) integrating facies descriptions with gamma-ray and porosity log data; (3) defining field-wide high frequency sequences based on wireline logs and cycle stacking patterns; (4) developing a sequence-based reservoir framework and 3-dimensional reservoir architecture; (5) defining porosity and permeability relationships for facies groups based on rock fabric characteristics. In Fullerton Field, the San Andres Formation comprises high frequency cycles of upward shoaling shallow-marine carbonates. Studies of nine cores (1730 ft) in FSAU reveal four peritidal and five shallow subtidal depositional facies based on texture, fossil assemblages, and sedimentary structures. Peritidal facies are dominantly laminated carbonate mudstones, interpreted as deposited on an intermittently exposed tidal flat. Shallow subtidal facies are peloid and mollusk dominated wackestones and packstones, interpreted as deposited in a shallow protected lagoon. Cycle stacking patterns indicate four complete upward shallowing high frequency sequences. Comparison of high frequency sequences between cored wells shows a high degree of similarity in the overall generalized vertical sequence, especially in the proportions of peritidal and subtidal components within each sequence. Three-dimensional reservoir characterization, using 132 gamma ray and porosity logs, reveals that depositional sequences are largely flat-lying with local topographic variation identified as the fundamental influence on lateral facies distribution within the reservoir section. Integration of core and petrophysical data from surrounding fields places FSAU in the larger sequence stratigraphic framework of the Central Basin Platform. The regional depositional sequence formed a series of depositional environments ranging from intermittently exposed to open marine. San Andres facies developed during south-easterly progradation of shallow water tidal flat and sabkha sediments over a deeper open marine shelf. / text

La capture et le stockage géologique du CO2 constituent une option importante de limitation des émissions de gaz à effet de serre au niveau des pôles industriels et des centrales de production d’énergie. Les gaz capturés à l’issu de ces chaînes de production ne sont pas constitués de CO2 pur mais contiennent une fraction (jusqu’à 10 %) de gaz annexes qui sont essentiellement Ar, N2, SOx et NOx. Ces gaz étant pour la plupart très réactifs il est essentiel de connaître leur impact sur les conditions physico-chimiques du réservoir géologique d’accueil, ainsi que sur l’environnement dans le cas d’une de contamination des aquifères voisins du stockage. Des expérimentations en laboratoire ont simulé le vieillissement de roches de réservoir et couverture en provenance d’un réservoir carbonaté du Bassin aquitain et d’assemblages minéralogiques synthétiques dans des conditions de séquestration géologique. Les roches associées à une saumure sont altérées au contact de divers composés gazeux à 100 bar et 150°C sur une durée d’un mois : CO2 pur, SO2, NO pur et un mélange contenant majoritairement du CO2 et des fractions de Ar, N2, SO2, O2. Chaque expérience est comparée à une expérience témoin où le composé gazeux est remplacé par de l’azote. Le CO2 ne montre qu’une réactivité limitée sur les minéraux des roches. Le NO et le SO2 montrent une réactivité intrinsèque passant par des dismutations en phase aqueuse ou vapeur induisant une forte altération de la roche par une attaque acide couplée à une oxydation poussée des minéraux constitutifs des roches. Le mélange de gaz montre de la même façon une réactivité double : le S02 s’oxyde en acide sulfurique s’attaquant aux carbonates et minéraux argileux et l’O2 oxyde tous les minéraux possédant du fer ou du soufre réduit. Les gaz annexes contrôlent donc la réactivité des roches en grande profondeur. Leur présence pourrait complètement changer le comportement des roches (porosité, rhéologique) lors du stockage. Leur implication devra être anticipée dans chaque cas concret de stockage en fonction de la composition du gaz d’injection, de la minéralogie et des propriétés pétrophysiques des roches. / Capture and geological storage of CO2 are an main option to limit GHEG emissions of industrial poles and power plants. The captured gases are not constituted by pure CO2 but contain a fraction (until 10 %) of other gases : Ar, N2, SOx and NOx. Most of these gases are highly reactive and could have a strong influence on physical and chemical conditions of the milieu and on the environmement if contamination of neighbour aquifers occurs by leakages. Several laboratory experiments investigated the reactivity of carbonated reservoir and cap rocks from the Aquitaine Basin as well as the reactivity of synthetic mineralogical blends in geologically relevant P-T conditions. The rocks, associated to brine, were altered in presence of various gaseous components at 100 bar and 150°C during one month : pure CO2, pure SO2, pure NO and a CO2 mixture containing fractions of Ar, N2, SO2 and O2. Each experiment was compared with a blank in which the initial gas was replaced with pure N2. Pure CO2 show a limited reactivity on the rocks. NO and SO2 show a intrinsic reactivity by disproportionations in aqueous or vapour phases implying a high alteration of rocks by compled acid – base and oxidation mechanisms. The gas mixture show also a double reactivity : SO2 is oxidized in sulphuric acid dissolving carbonates and clay minerals and O2 oxidizes all reduced mineralogical phases. These gases even in limited fractions control the reactivity of rocks. Their presence could change the behaviour of the rock toward gas and induce positive as well as negative transformations. Their implication must be checked for each geological storage as a function of gas composition, mineralogy and petrophysical.

The original aim of my diploma thesis was examination of fixed samples of cladocerans from the Daphnia longispina species complex from reservoirs Vír and Vranov for the presence of 4 groups of microparasites: microsporidia, oomycetes, the protozoan Caullerya mesnili, and the yeast Metschnikowia bicuspidata. The next aim was to determine the effect of parasites on Daphnia fecundity, and determination of their spatial and temporal distribution within reservoirs. From the total number 4452 of examined Daphnia females, however, only 56 individuals were infected. This number was not sufficient for the planned analyses. As I recorded for all examined individuals the clutch size, I thus dealt to a large extent with an alternative issue: the temporal and spatial variation of, and the influence of environmental factors on Daphnia fecundity. Both studied reservoirs are characteristic by canyon-shaped profile that allows formation of environmental gradients on the horizontal as well as vertical axis. The results confirm that reservoir identity, season, and location within the reservoir (or gradient of food supply) have all significant effects on fecundity. During my work I have encountered difficulties associated with determining microparazites from fixed zooplankton samples. The appendix section of my thesis...

The main objective of this thesis is to prove the influence of small water reservoirs on the extreme runoff situations in a watershed of upper Otava River. The system of small water reservoirs represents an effective part of flood protection, which can be realized without greater changes of landscape. The research part of this thesis includes a summary of knowledge about rainfall-runoff process, small water reservoirs and hydrological modeling. The work is applied to model watershed of Roklanský creek, which is situated in a central part of Šumava Mountains. There are a few rain gauges and laser sensors situated in this watershed, whose are needed for the modeling process. The thesis contains a selection of appropriate data and methods for a creation of digital model of terrain. This digital model of terrain is used for creation of most of the parameters, whose are used for modeling of rainfall- runoff process. This modeling is done in hydrological modeling program HEC - HMS (Hydrologic Engineering Center - Hydrologic Modeling System). HEC - HMS is one of the most used simulation programs. The main part of the thesis is a simulation of rainfall-runoff process, applied to two real rainfall-runoff episodes. Next important part of the thesis is a comparison of this simulation with and without...

L'érosion hydrique touche près de 3 millions d'hectares des sols agricoles en Tunisie, et constitue une menace pour la durabilité des retenues collinaires destinées à mobiliser les eaux de surface. La très forte densité des systèmes ravinaires en Tunisie, comme dans bon nombre de régions méditerranéennes, pose la question de leur rôle dans le comblement des retenues. Dans ce contexte, l'objectif général de ce travail de thèse est de proposer une méthodologie qui permette d'évaluer la contribution relative de l'érosion ravinaire (ravines/oued) et de l'érosion de surface (diffuse/ rigoles) dans les flux de sédiments à l'exutoire des petits bassins versants (0,1-10 km²) sur des périodes d'observations suffisamment longues (une quinzaine d'année). La démarche proposée s'appuie sur la méthode de traçage des sources de sédiments développée par Walling (1999), et consiste à exploiter le caractère stable de certains éléments pour discriminer les sources de sédiments accumulés dans les retenues collinaires. Les différentes étapes de cette approche consistent en : i) l'identification des traceurs potentiels; ii) l'analyse de ces traceurs dans les échantillons «source» et dans les carottes prélevées dans les sédiments de la retenue; iii) l'application d‘un modèle de mélange associé à un modèle de Monte Carlo. Les résultats de cette méthode de traçage testée prioritairement sur un bassin versant expérimental (Kamech) ont été par la suite validés par deux approches indépendantes d'estimation des volumes de terres érodés. Sur Kamech, les résultats montrent la prédominance de l'érosion de surface qui représente près de 80% de l'érosion totale dont le taux moyen atteint 15 t/ha/an. Cette application a également permis de dégager des recommandations concernant la stratégie d'échantillonnage des carottes au sein des sédiments piégés dans les retenues collinaires pour limiter les incertitudes liées à l'échantillonnage. La méthode a ensuite été appliquée à quatre autres bassins versants choisis pour représenter au mieux la diversité des paysages de la Dorsale Tunisienne et du Cap Bon. La comparaison des résultats pour les cinq bassins versants étudiés montre une large variabilité des comportements érosifs : trois bassins montrent une prédominance de l'érosion de surface et nécessitent la mise en place de pratiques culturales protectrices de la ressource en sol alors que les deux autres bassins sont dominés par l'érosion ravinaire et nécessitent de recourir prioritairement à des mesures structurelles telles que des aménagements de ravines. Ces différences de comportements érosifs entre bassins ont été confrontées aux caractéristiques des sites en vue de fournir des clés de prédiction.Mots clefs : Erosion ravinaire. Erosion de surface. Bassins versants. Retenues collinaires. Traçage des sources de sédiments. Télédétection. Tunisie. / Water erosion affects nearly 3 million hectares of agricultural soil in Tunisia, and presents a threat to the sustainability of reservoirs to store surface waters. The high density of gully systems in Tunisia, like in many Mediterranean regions, raises the question of their role in the siltation of reservoirs. In this context, the objective of this thesis is to propose a methodology for evaluating the relative contribution of gully erosion (gullies/channel) compared to surface erosion (rill and interrill) in sediment fluxes at the outlet of small catchments (0.1-10 km ²), for pluri-annual periods (about 15 years). The proposed approach is based on the method of fingerprinting sediment sources developed by Walling et al. (1999), and takes advantage of the stable nature of certain elements to discriminate the origin of sediment trapped in reservoirs. The different steps of this approach consist in i) the identification of potential tracers adapted to the objectives of the study, ii) the quantification of these tracers in sources samples and in sediment cores, iii) the application of a mixing model combined with a Monte Carlo model. The results of this fingerprinting approach primarily tested on the Kamech experimental catchment were subsequently validated using eroded soil volumes estimated by two independent approaches. The results for this catchment show the dominance of surface erosion which represents nearly 80% of the 15 t/ha/year of total erosion. In addition, guidelines for method application have been proposed, including the implementation of a core sampling strategy which limits the level of uncertainty to less than 10%. The method was then applied to four other catchments representative of the diversity of the Tunisian Dorsal and Cape Bon landscapes. The comparison of the results for the five studied catchments shows a wide variability of erosion behaviour. Surface erosion is the dominant process in three catchments which require the establishment of protective cultivation of the soil resource. The two other catchments are dominated by gully erosion and require the priority use of structural measures such as improvements of gullies and bank channel protection. These differences between catchments have been related to the characteristics of the sites in order to identify predictive factors.Keywords: Gully Erosion. Rill and Interrill Erosion. Catchments. Reservoirs. Sediment Fingerprinting. Remote Sensing. Tunisia.

Orientador: Denise de Campos Bicudo / Resumo: Este estudo baseou-se em um banco de dados limnológicos e biológicos (diatomáceas de sedimento superficial e da coluna da água) de 33 reservatórios com gradiente trófico (ultraoligotrófico a hipereutrófico) distribuídos na região sudeste do Estado de São Paulo. Visou, como primeira etapa, calcular os ótimos e as tolerâncias ecológicas (etapa de regressão) das espécies de diatomáceas com a finalidade de propor um índice de diatomáceas para avaliar o estado trófico de represas, bem como um modelo de função de transferência diatomácea-fósforo (etapa de calibração) para inferir níveis pretéritos de fósforo da água. Além disso, visou avaliar o efeito da eutrofização sobre a homogeneização taxonômica e funcional das comunidades de diatomáceas. As amostras do sedimento superficial (n = 113) e do plâncton (verão e inverno, n = 226) foram obtidas entre 2009 e 2014. O método da média ponderada (WA) foi utilizado para a etapa de regressão (ótimo e tolerância das espécies), e modelos de regressão clássica e inversa foram testados para a etapa de calibração para a proposição do índice trófico de diatomáceas e para o modelo de função de transferência diatomácea-fósforo. Foram calculados os ótimos e as tolerâncias de fósforo total para 58 (sedimento superficial) e 53 (plâncton) espécies de diatomáceas. O modelo proposto com base nas diatomáceas do sedimento superficial apresentou melhor habilidade (r2 0.71, p<0.001, RMSE 49.43 μg L-1) do que as planctônicas para proposição do índice de esta... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: This study was based on a limnological and biological database (surface sediment and water column diatoms) of 33 reservoirs with trophic gradient (ultraoligo- to hyperereutrophic) distributed in the southeastern region of São Paulo State. The first aim was to calculate the optimum and ecological tolerances (regression stage) of diatom species in order to propose a diatom index to evaluate the trophic state of reservoirs, as well as a model of diatom-phosphorus transfer function (calibration step) to infer past levels of water phosphorus. In addition, it aimed to evaluate the effect of eutrophication on the taxonomic and functional homogenization of diatom communities. Surface sediment (n = 113) and plankton (summer and winter, n = 226) samples were obtained between 2009 and 2014. The weighted average (WA) method was used for the regression step (optimal and species tolerance), and classical and inverse regression models were tested for the calibration step for the proposition of the trophic index of diatoms and for the diatom-phosphorus transfer function model. Optimum and tolerances for total phosphorus were calculated for 58 (surface sediment) and 53 (plankton) diatom species. The model based on the surface sediment diatoms presented better ability (r2 0.71, p<0.001, RMSE 49.43 μg L-1) than phytoplankton diatom to propose the trophic diatom index of reservoirs (TDIR). The transfer function model showed high predictive ability (r2 0.80) and was based on 63 diatom species (su... (Complete abstract click electronic access below) / Doutor

Nas últimas décadas a Organização das Nações Unidas apontou que a escassez de água doce disponível para consumo poderia ser uma barreira para desenvolvimento de todos os países. Essa realidade torna-se ainda mais alarmante se for levado em conta o aumento na densidade demográfica, sobretudo nas megalópoles onde os recursos hídricos ainda sofrem por conta da contaminação pelas fontes de poluição pontuais. Nos países subdesenvolvidos esse panorama é ainda mais crítico. A falta de recursos para planejamento e execução de obras de saneamento faz com que a degradação dos corpos d\'água ocorra em ritmo ainda mais acelerado, trazendo um risco eminente para a população dessas regiões devido à disseminação de doenças, por exemplo. Face ao exposto, é premente a necessidade de formulação de projetos para monitorar os recursos hídricos, sobretudo aqueles inseridos em áreas urbanas, utilizados para o abastecimento de grande regiões metropolitanas, como é o caso do Complexo Billings-Guarapiranga, situado em São Paulo. Nessas regiões, os rios e reservatórios acabam perdendo a característica de patrimônio público e tornam-se elementos abióticos na paisagem, sem valor cultural ou como necessidade básica para a vida. Contudo, infelizmente o atual sistema de gestão pública no Brasil está em crise e, por conta disso, também é necessário inovar a maneira como os monitoramentos são realizados, visando reduzir os gastos com trabalhos de campo para coleta de amostras e análise das mesmas. Neste contexto, o uso das ferramentas de geoprocessamento aliadas aos produtos obtidos por sensores remotos pode contribuir efetivamente para a reversão do atual patamar de destruição dos ecossistemas aquáticos continentais. A ideia é criar processos que permitam não somente avaliar a qualidade dos reservatórios mas, também, auxiliar na criação e atualização dos atuais planos diretores e zoneamentos ecológicos-econômicos. O presente trabalho apresenta um conjunto de ferramentas capazes de auxiliar na gestão dos recursos hídricos, tanto na avaliação do estado trófico de reservatórios, como na análise do risco ecológico nas bordas das bacias de captação. Através da modelagem de biomassa fitoplanctônica pela concentração de Clorofila-A, da extração de redes de drenagem e da análise do uso e ocupação do solo nas bacias de captação é possível ter uma ideia bastante concreta do risco ecológico associado aos recursos hídricos. Os resultados obtidos neste trabalho, em comparação com trabalhos desenvolvidos por outros autores, aponta a potencialidade da metodologia proposta. Ainda, o processamento da série de imagens Landsat 5/TM auxiliou na identificação da dinâmica espacial da concentração de Clorofila-A, permitindo a identificação das áreas com contaminação persistente 2003 e 2010. Por fim, acredita-se que o leitor deve sentir-se encorajado no desenvolvimento de novos modelos e atualização dos modelos atuais. O conjunto de ferramentas propostas pode contribuir, efetivamente, para a gestão dos recursos hídricos / In recent decades the United Nations published that the scarcity of fresh water available for consumption could be a barrier to development of all countries. This reality becomes even more alarming considering the increased in population density, especially in megacities where water resources are still suffering because of punctual pollution sources. In underdeveloped countries this scenario is even more critical. Lack of financial resources for sanitation planning and implementation causes faster degradation of water bodies, bringing an imminent risk to these region populations due to disease spread, for example. In this way, its necessary to reformulate the water resources monitoring projects, especially those placed in urban areas, used for large metropolitan areas supply, such as the Billings-Guarapiranga Complex, located in São Paulo. In these regions, rivers and reservoirs end up losing the characteristic of public assets and become abiotic elements in the landscape without cultural value or as a basic need for life. However, unfortunately the Brazilian current public management system is in crisis and so on we need to innovate the way the monitoring projects is performed in order to reduce field work costs to collect samples and analyze them. In this context, the use of GIS tools, combined with the products obtained by remote sensors can effectively contribute to the reverse the current level freshwater ecosystems degradation. The idea is to create processes not only to assess the reservoirs quality, but also helps to create and update the current master plans and ecological-economic zoning. This paper presents a set of tools to assist the water resources management, both in assessing of reservoirs trophic status, as in the analysis of catchment basin border ecological risk. It is possible to have a very concrete idea of the ecological risk associated with water resources through the phytoplankton biomass modeling by concentration of chlorophyll-A, the extraction of drainage networks and the analysis of land use in the catchment basin can. The results obtained here compared to others, points out the potential of the proposed methodologies. Furthermore, processing of Landsat 5/TM series helped in identifying chlorophyll-A concentration spatial dynamics, allowing the identification persistent contamination areas in 2003 and 2010. Finally, we believed the reader should feel encouraged to develop new models and update the current ones. The set of proposed tools can effectively contribute to the water resources management

Os tripanosomas são parasitas hemoflagelados com importância médica para humanos e animais domésticos. Surtos de infecções agudas graves por T.vivax têm sido relatados em todo Brasil onde perdas econômicas e falhas reprodutivas são observadas. Neste trabalho, uma infecção experimental por T. vivax em ovinos confirmou sua transmissão transplacentária. Em relação à epidemiologia de T. vivax, para entender o papel dos jumentos em surtos no Semiárido Brasileiro, foram realizados ensaios parasitológicos e moleculares em infecções naturais e experimentais. Nossos resultados mostraram animais assintomáticos, portanto, podem atuar como potenciais reservatórios. Além disso, estudos filogenéticos revelaram uma diversidade genética inesperada em tripanossomas no Leste da África, especialmente em moscas tsé-tsé. Novos genótipos de T. vivax foram caracterizados e tripanossomas do subgênero Nanomonnas se mostraram prevalentes nestas infecções. Nesta abordagem, conseguimos identificar T. suis e novas espécies do subgênero Pycnomonas presentes em animais selvagens e domésticos. / Trypanosomes are hemoflagellates parasites with medical importance to humans and domestic animals. Outbreaks of severe acute infections by T. vivax have been reported throughout Brazil, where economic loss and reproductive failure are observed. In this study, an experimental infection by T. vivax in sheep confirmed the transplacental transmission of this parasite. Regarding T. vivax epidemiology, to understand the role played by donkeys in outbreaks in the Brazilian Semiarid, we performed parasitological and molecular assays in naturally and experimentally infections. Our findings show that infected donkeys are asymptomatic and, thus, are potential reservoirs. In addition, phylogenetic studies have revealed an unexpected genetic diversity in East Africa, especially in tsetse flies. New genotypes of T. vivax were characterized and trypanosomes of the subgenus Nanomonnas were prevalent in these infections. In this approach, we can identify T. suis and new species of the subgenus Pycnomonas present in wild and domestic animals.