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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
71

Fast and robust phase behavior modeling for compositional reservoir simulation

Li, Yinghui, January 1900 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 2007. / Vita. Includes bibliographical references.
72

Investigation of artificial neural networks, alternating conditional expectation, and Bayesian methods for reservoir characterization /

Kapur, Loveena, January 1998 (has links)
Thesis (Ph. D.)--University of Texas at Austin, 1998. / Vita. Includes bibliographical references (leaves 216-221). Available also in a digital version from Dissertation Abstracts.
73

Restimulation candidate selection using virtual intelligence

Mohamad, Khalid Y. January 2000 (has links)
Thesis (M.S.)--West Virginia University, 2000. / Title from document title page. Document formatted into pages; contains ix, 176 p. : ill. (some col.). Includes abstract. Includes bibliographical references (p. 64-65).
74

Reservoir characterization using intelligent seismic inversion

Artun, F. Emre. January 2005 (has links)
Thesis (M.S.)--West Virginia University, 2005. / Title from document title page. Document formatted into pages; contains xii, 82 p. : ill. (some col.), maps (some col.). Includes abstract. Includes bibliographical references (p. 80-82).
75

Synthesis of a high performance surfactant for application in alkaline-surfactant-polymer flooding in extreme reservoirs

Elias, Samya Daniela de Sousa January 2016 (has links)
Thesis (MTech (Chemical Engineering))--Cape Peninsula University of Technology, 2016. / Due to the rising cost involve with bringing new fields on stream, of producing residual crude from matured fields, and the significant enhancement in oil recovery provided when compared to conventional water-flooding, increasing attention is being given to chemical flooding technologies. This is particular of interest in mature fields that had previously undergone water flooding. These methods entail injecting chemicals such as surfactant, alkali, and polymer often in mixture into reservoirs to improve oil recovery. In this study a sulfonated surfactant was produced from cheap waste vegetable oils and its performance was assessed in terms of thermal stability at reservoir conditions, adsorption on different reservoir materials, gas chromatography characterization and a limited interfacial tension measurement to evaluate its ability to improve the recovery of crude oil. Waste vegetable oils have great potential as a sustainable and low cost feedstock as well as its low toxicity.
76

Análise de incertezas através de caracterização integrada de reservatório de petróleo / Hydrocarbonates reservoir uncertainty analysis throught integrated characterization

Guillou, Olivier 16 August 2018 (has links)
Orientador: Denis José Schiozer / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-16T02:47:54Z (GMT). No. of bitstreams: 1 Guillou_Olivier_M.pdf: 7496791 bytes, checksum: 64b1e03f7a1baa620f4a354c4e790f09 (MD5) Previous issue date: 2010 / Resumo: As crescentes dificuldades encontradas na exploração e produção de petróleo, tais como a diminuição das grandes descobertas, o afastamento da costa e as profundidades cada vez maiores dos campos, criam uma necessidade permanente de inovação. A fim de melhor conhecer e dominar os reservatórios situados em regiões remotas, novas ferramentas e novas metodologias precisam ser desenvolvidas. Com capacidade computacional em constante aumento e algoritmos avançados, esta demanda pode ser satisfeita. A partir de novas metodologias de integração de sísmica 3D desenvolvidas e integradas em um processo de otimização baseado em modelagem a posteriori, diversos resultados válidos tem sido obtido. Neste contexto, a caracterização de reservatórios condicionada a atributos sísmicos se revelou uma maneira eficiente de melhorar a qualidade sísmica dos modelos assim como o respeito dos modelos gerados (Barens et al, 2004). Esta dissertação propõe comparar os resultados de quatro metodologias de caracterização de reservatório e os seus respectivos impactos na análise de risco do campo. O caso de estudo é realizado em um campo de turbiditos situado nas águas profundas da costa oeste africana a partir de cinco poços exploratórios e uma exploração sísmica 3D de boa qualidade / Abstract: The growing difficulties encountered in petroleum exploration and production, such as declining discoveries, increasing coastal distances and field depth, create a constant need for innovation. To improve the knowledge and dominate reservoirs located in remote areas, new tools and methodologies must be developed. With the steady increase in computing power and the birth of new algorithms, this demand can be satisfied and project risks can be reduced. From new 3D seismic integration methodologies developed and integrated into an optimization process based on forward modeling, different valid results have been obtained. In this context, seismic constraint characterization has shown an effective way to improve the seismic quality and the relevance of generated models (Barens et al, 2004). This dissertation proposes to compare the results of four reservoir characterization methodologies on a field development risk analysis. The case study is realized on a deep offshore West African turbidites with a relevant exploration wells number and a good 3D seismic survey quality / Mestrado / Reservatórios e Gestão / Mestre em Ciências e Engenharia de Petróleo
77

Mitigação de incertezas através da integração com ajuste de histórico de produção e técnicas de amostragem / Uncertainty mitigation through integration with history matching and sampling techniques

Vasconcelos, David Dennyson Sousa 07 November 2011 (has links)
Orientadores: Denis José Schiozer, Célio Maschio / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica e Instituto de Geociências / Made available in DSpace on 2018-08-18T20:59:19Z (GMT). No. of bitstreams: 1 Vasconcelos_DavidDennysonSousa_M.pdf: 1907776 bytes, checksum: f7eeb89b73385df9b024d60d9968b96e (MD5) Previous issue date: 2011 / Resumo: As incertezas geológicas influenciam diretamente a previsão de comportamento de reservatórios de petróleo, podendo, muitas vezes, tornar mais complexo o uso de ferramentas como simuladores de fluxo. A integração de técnicas de redução de incertezas e ajuste de histórico ganha um importante destaque neste processo, principalmente devido às limitações apresentadas pelas técnicas tradicionais de ajuste de histórico, sobretudo em campos com poucos dados de produção e maiores incertezas. O objetivo principal desse trabalho é obter um ajuste de histórico probabilístico a partir da redução das incertezas do modelo de reservatório. A proposta desse estudo é apresentar contribuições a uma metodologia existente, com o objetivo de possibilitar o tratamento de um elevado número de atributos incertos e aumentar a eficiência do processo. O método consiste em um procedimento dinâmico de calibração de propriedades do reservatório, utilizando dados observados e técnicas de amostragem. Os atributos considerados, discretizados em níveis de incertezas (com uma probabilidade associada), são submetidos a um processo de amostragem, com o método de Hipercubo Latino e, posteriormente combinados estatisticamente. Cada combinação entre níveis dos diferentes atributos resulta em um modelo de simulação e, após realizadas as simulações, novas probabilidades são estimadas, para cada nível, a partir de um procedimento que utiliza a diferença entre os dados observados e simulados, relativos a cada modelo. A qualidade do ajuste obtido pode ser avaliada a partir das curvas de incertezas, compostas por modelos representativos das probabilidades iniciais e finais de cada atributo e através dos indicadores propostos nesse trabalho, como variabilidade das probabilidades e afastamentos por poço. Os resultados obtidos indicam um método capaz de fornecer resultados confiáveis no processo de mitigação de incertezas, quando há dados de histórico disponíveis. O aumento na qualidade dos resultados com esse método, para as situações onde os atributos possuem mais níveis discretos que o convencional (normalmente são 3 níveis), depende do esforço computacional (em termos do número de simulações). Contudo, não há um aumento expressivo do número de simulações, como ocorre na técnica de árvore de derivação usada em trabalhos anteriores / Abstract: The geological uncertainties influence directly the prediction of reservoir behavior, making more complex the use of tools such as flow simulators. The integration between mitigation uncertainties techniques and history matching gains an important emphasis in this process, mainly due to the limitations presented by history matching traditional techniques, especially in areas with little observed data and greater uncertainties. The main objective of this work is to set a probabilistic history matching from the mitigation of reservoir uncertainty. The purpose of this study is to provide input to an existing methodology, in order to allow treatment of a large number of uncertain attributes and increase process efficiency. The method involves a dynamic procedure of global and local calibration of the geological model, using observed data and sampling techniques. The considered attributes, discretized into uncertainty levels (with an associated probability), are undergoing a sampling process, with Latin Hypercube method and then statistically combined. Each combination among levels of different attributes results in a complete simulation model, and after the simulations are performed, new probabilities are estimated for each level, from a procedure that uses the difference between observed and simulated data for each model. The quality of the history matching process can be evaluated from the uncertainty curves, composed of representative models of initial and final probabilities of each attribute, and using the indicators proposed in this work, as probabilities variability and the difference between observed and simulated data by well. The results obtained with this methodology indicate a tool capable of providing reliable results in the uncertainty mitigation process, when there is observed data available. The increase in quality of results with this method, for situations where the attributes has a number of discrete levels higher than the conventional technique (3 levels) depends on the computational effort (in terms of simulations number), but without the significant increase in the simulations number, as in the derivation tree technique used in previous works / Mestrado / Reservatórios e Gestão / Mestre em Ciências e Engenharia de Petróleo
78

Integração de análise de incertezas e ajuste de histórico = aplicação em um caso complexo / Integration of uncertainty analysis with history matching : application in a complex case

Silva, Luciana dos Santos 19 August 2018 (has links)
Orientador: Denis José Schiozer / Dissertação (mestrado) - Universidade Estadual de Campinas, Faculdade de Engenharia Mecânica / Made available in DSpace on 2018-08-19T21:21:13Z (GMT). No. of bitstreams: 1 Silva_LucianadosSantos_M.pdf: 12675920 bytes, checksum: 63532a17aa12aa538936a8b7e2f0b435 (MD5) Previous issue date: 2011 / Resumo: A grande quantidade de incertezas presente na modelagem de reservatórios gera riscos na previsão de comportamento de um campo de petróleo. Assim, torna-se imprescindível o ajuste de histórico, que é a calibração do modelo de simulação do reservatório com os dados dinâmicos observados, aproximando o modelo da realidade e gerando previsões mais confiáveis. Diversas metodologias surgiram para integrar a análise de incertezas com o ajuste de histórico, mas devido à complexidade do processo, algumas delas só se aplicam a casos simples. A proposta deste trabalho é aplicar os métodos desenvolvidos por Moura Filho (2006), Becerra (2007) e Maschio et al. (2010) em um caso complexo sintético, similar a um modelo real de um reservatório de petróleo e avaliá-los para propor melhorias na metodologia. A técnica consiste em utilizar as diferenças entre os dados de produção observados e os simulados para reduzir as incertezas do reservatório, calculando as probabilidades dos níveis dos parâmetros incertos. Para isso, os atributos incertos são discretizados em três níveis e é feita uma análise de sensibilidade para escolher os atributos críticos, os quais são combinados através da árvore de derivação para gerar os diferentes modelos de simulação. Com os dados históricos (medidos) e simulados destes modelos, é feita a redistribuição das probabilidades dos níveis utilizando e comparando dois métodos: o de Moura Filho e Becerra (Método 1) e o de Maschio et al. (Método 2). Os resultados deles não mostraram boa eficiência na redução das incertezas para o caso estudado, pois as curvas continuaram muito espalhadas com relação ao histórico. Sendo assim, foram criados o Método 3, utilizando as melhores práticas da formulação dos dois estudados com o objetivo de tornar a metodologia mais robusta para uso em casos reais, e o Método 4, que é uma reaplicação do Método 3 após a redefinição dos valores dos níveis dos atributos. Uma comparação dos resultados dos quatro métodos mostra a evolução da redução das incertezas. Além disso, consegue-se diminuir a dispersão dos modelos representativos, centralizando-os com relação ao histórico de produção, o que permite uma melhor previsão de produção e maior confiabilidade na análise de risco de projetos futuros / Abstract: The large amount of uncertainties in reservoir modeling increases petroleum production forecast risks. Therefore, the history matching, which refines the simulation model to closely reproduce production data, is a vital procedure once it approximates numerical models to reality providing reliable predictions. Many methodologies were developed to integrate uncertainty analysis and history matching in order to mitigate the reservoir uncertainties by using the observed data, but due to the process complexity, some of them are applicable only in simple cases. In this context, the present work aims to evaluate the application of existing methods, developed by Moura Filho (2006), Becerra (2007) and Maschio et al. (2010), in a synthetic complex model (i.e. similar to a real field) and propose new methods with some improvements to be applied in real cases of the petroleum industry. The main characteristic of these methods is the use of differences between observed and simulated data to recalculate the probabilities distribution of uncertain parameters with the purpose of reducing reservoir uncertainties. To apply the methods, the uncertainty attributes are discretized in three levels and a sensibility analysis is done to select the critical attributes, which are combined by a derivative tree generating different simulation models. With history and simulated data of these models, the redistribution of occurrence probabilities is made with different formulas: Moura Filho e Becerra (Method 1) and Maschio et al. (Method 2). These two methods are compared and their results don't show good efficiency in uncertainty reduction of the studied case, because the final curves remain widely scattered around history data. Then, two methods are proposed, Method 3, which combines the best practices of the two reviewed ones, making it robust to be used in real cases with a great number of wells and production functions to be adjusted such as water production and pressure. The second proposed one, Method 4, is a reapplication of the third method with a redefinition of attribute values in order to refine the results. A comparison of the results of the four methods shows an evolution in the uncertainty reduction. Besides that, there is a decrease in the dispersion of the representative curves, which are centralized around the history data, providing a better production forecast and greater reliability in risk analysis of future projects / Mestrado / Reservatórios e Gestão / Mestre em Ciências e Engenharia de Petróleo
79

Sedimentological re-interpretation of the early cretaceous oil reservoir in the Northern Bredasdorp Basin, offshore South Africa

Asiashu, Mudau January 2015 (has links)
>Magister Scientiae - MSc / This study was aimed at determining the sedimentary environment, its evolution and facies areal distribution of the Upper Shallow Marine (USM, Late Valanginian). The study was conducted in wells E-S1, F-AH4 and E-W1 in the Bredasdorp basin between E-M and F-AH fields, located in a basinwards transect roughly transverse to the palaeocoast. The wells were studied by logging all the cores in detail between the chosen intervals, followed by facies analysis. Each core log was tied with its respective gamma ray and resistivity well logs. The logs were then correlated based on their log signatures, trends and facies interpretation. The Gamma ray logs show a fining-upwards and coarsening-upwards trend (“hour-glass shape”) in E-S1 and F-AH4 while in E-W1 it shows more accommodation space. These trends are believed to have been influenced by relative sea level changes, such as transgression and regression. Facies analysis identified seven facies in the study area: Facies A, B, C, D, E, F and G. Facies A, B and C were interpreted as fair-weather and storm deposits of the offshore-transition zone, shoreface and foreshore respectively. Facies D was considered as lagoonal mud deposits, while Facies E and F were interpreted as tidal channel and tidal bar deposits respectively. Finally Facies G was considered as fluvial channel deposits. The facies inferred that the sedimentary environment of the study area is a wave-dominated estuary or an Island-bar lagoon system. This led to the production of a conceptual model showing the possible locations for the three wells in the Island bar-lagoon system. The conceptual model inferred the previous findings from PGS (1999) report, that the Upper Shallow Marine beds were deposited in a tidal/estuarine to shoreface setting. This model also supports the findings of Magobiyane (2014), which proposed a wave-dominated estuary for the Upper Shallow Marine reservoir between E-M and F-AH fields, located west of the study area.
80

Reservoir Characterization and Outcrop Analogs to the Navajo Sandstone in the Central Utah Thrust Belt Exploration Play

Dalrymple, Ashley 07 July 2007 (has links) (PDF)
Reservoir heterogeneity plays an important role in oil field economics and completion strategies. We herein characterize the reservoir heterogeneity of the Early Jurassic Navajo Sandstone in the Justensen Flat/Devils Canyon area of the San Rafael Swell, Utah. These outcrops are located approximately 60 kilometers (45 mi) east of the recently discovered Covenant oil field which is located in the central Utah thrust belt exploration play. The reservoir for the Covenant field is the Navajo Sandstone. This study can serve as an outcrop analogue for this developing play and other eolian reservoirs worldwide. There are eight facies within the Navajo Sandstone in the Justensen Flat/Devils Canyon area based on differences in primary and secondary sedimentary structures, sedimentary texture, petrology, porosity/permeability, and other macro-scale features of the outcrop. Three facies were deposited by eolian dunes. These serve as the primary reservoir facies of the Navajo in the Justensen Flat/Devils Canyon area, displaying relatively high porosity and permeability (approximately 28 percent porosity and 100 mD of permeability). Five interdune facies display finer grain size, more abundant cement, and relatively lower porosity and permeability (approximately 18 percent porosity and 29 mD of permeability). Four of the five inderdune facies have variable porosity and permeability or are not laterally extensive (tens of meters). These four facies act as baffles to fluid flow within the reservoir. One interdune facies, the Wavy Algal Matted facies (WAM), displays very low porosity (10 percent) and permeability (0.265 mD) based on 4 samples, and is laterally extensive in the field area (greater than 1 km2). There are nine facies in the Wolverine Federal 17-3 core from the Covenant Field, four of which are tidally influenced. This is unique compare to the Justensen Flat/Devils Canyon outcrop. Tidal influence was apparently present in western Utah but did not have a direct influence on sedimentation 60 kilometers (45 mi) to the east. The Large Trough Cross-stratified (LTC) facies, which serves as the primary reservoir of the Navajo Sandstone, was observed in both outcrop and core. The laterally extensive, low permeability WAM facies was also present in both core and outcrop, suggesting the possibility of reservoir partitioning within oil fields having eolian reservoirs similar to the Navajo Sandstone.

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