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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

Monitoring Expertise: A perspective on environmental impacts monitoring in northeast British Columbia

Twerdoclib, Christine 08 September 2015 (has links)
The shale gas industry in northeast British Columbia is rapidly expanding and is promoted by the provincial government as a promising economic venture for the entire province. However, the industry is having impacts on the traditional territory of the Fort Nelson First Nation, although they have constitutionally recognized treaty rights to continue to use the land to meet their subsistence needs. I conducted this research in partnership with the Fort Nelson First Nation Department of Lands and Resources, with a focus on critically assessing the challenges they face. This research focuses on determining how the Fort Nelson First Nation can protect their treaty rights by taking control of, or inserting themselves into the data collection and monitoring activities of the shale gas industry. Utilizing a theory of knowledge politics, this research analyzes two strategies that challenge what knowledge should count, and on what terms: (1) the Fort Nelson First Nation’s participation and appropriation of the professionalized science regime and (2) the development of the Fort Nelson First Nation’s community-based monitoring program and its ability to impact decision-making. Drawing on primary research, participant observation, literature reviews and document analyses, I argue that these strategies are crucial and can create – but do not guarantee – links to affecting natural resource management decisions. / Graduate
72

Public perceptions on fresh water use for hydraulic fracturing of the Duvernay Shale Gas Formation, Kaybob Area, Alberta

Jobson, Emily 06 March 2014 (has links)
The thesis research examined localized socio-environmental perceptions related to amplified fresh water requirements for hydraulic fracturing and subsequent flowback disposal activities. These requirements are associated with increasing shale gas development in the Duvernay formation, located within the Kaybob region of West-central Alberta, Canada. Fresh water refers to surface and groundwater with a total dissolved solids concentration of less than 4,000 ppm. Through recourse to a mixed methods approach, combined with triangulation as a method of further validation, the research demonstrates that there exists a public sensitivity related to fresh water use in the Kaybob region. This sensitivity arises from increasing development activities in the Duvernay shale gas formation. The thesis presents conclusions and recommendations whereby industry may address stakeholder concerns, and provides advice for future research.
73

Application of Fast Marching Method in Shale Gas Reservoir Model Calibration

Yang, Changdong 16 December 2013 (has links)
Unconventional reservoirs are typically characterized by very low permeabilities, and thus, the pressure depletion from a producing well may not propagate far from the well during the life of a development. Currently, two approaches are widely utilized to perform unconventional reservoir analysis: analytical techniques, including the decline curve analysis and the pressure/rate transient analysis, and numerical simulation. The numerical simulation can rigorously account for complex well geometry and reservoir heterogeneity but also is time consuming. In this thesis, we propose and apply an efficient technique, fast marching method (FMM), to analyze the shale gas reservoirs. Our proposed approach stands midway between analytic techniques and numerical simulation. In contrast to analytical techniques, it takes into account complex well geometry and reservoir heterogeneity, and it is less time consuming compared to numerical simulation. The fast marching method can efficiently provide us with the solution of the pressure front propagation equation, which can be expressed as an Eikonal equation. Our approach is based on the generalization of the concept of depth of investigation. Its application to unconventional reservoirs can provide the understanding necessary to describe and optimize the interaction between complex multi-stage fractured wells, reservoir heterogeneity, drainage volumes, pressure depletion, and well rates. The proposed method allows rapid approximation of reservoir simulation results without resorting to detailed flow simulation, and also provides the time-evolution of the well drainage volume for visualization. Calibration of reservoir models to match historical dynamic data is necessary to increase confidence in simulation models and also minimize risks in decision making. In this thesis, we propose an integrated workflow: applying the genetic algorithm (GA) to calibrate the model parameters, and utilizing the fast marching based approach for forward simulation. This workflow takes advantages of both the derivative free characteristics of GA and the speed of FMM. In addition, we also provide a novel approach to incorporate the micro-seismic events (if available) into our history matching workflow so as to further constrain and better calibrate our models.
74

Assessment of Eagle Ford Shale Oil and Gas Resources

Gong, Xinglai 16 December 2013 (has links)
The Eagle Ford play in south Texas is currently one of the hottest plays in the United States. In 2012, the average Eagle Ford rig count (269 rigs) was 15% of the total US rig count. Assessment of the oil and gas resources and their associated uncertainties in the early stages is critical for optimal development. The objectives of my research were to develop a probabilistic methodology that can reliably quantify the reserves and resources uncertainties in unconventional oil and gas plays, and to assess Eagle Ford shale oil and gas reserves, contingent resources, and prospective resources. I first developed a Bayesian methodology to generate probabilistic decline curves using Markov Chain Monte Carlo (MCMC) that can quantify the reserves and resources uncertainties in unconventional oil and gas plays. I then divided the Eagle Ford play from the Sligo Shelf Margin to the San Macros Arch into 8 different production regions based on fluid type, performance and geology. I used a combination of the Duong model switching to the Arps model with b = 0.3 at the minimum decline rate to model the linear flow to boundary-dominated flow behavior often observed in shale plays. Cumulative production after 20 years predicted from Monte Carlo simulation combined with reservoir simulation was used as prior information in the Bayesian decline-curve methodology. Probabilistic type decline curves for oil and gas were then generated for all production regions. The wells were aggregated probabilistically within each production region and arithmetically between production regions. The total oil reserves and resources range from a P_(90) of 5.3 to P_(10) of 28.7 billion barrels of oil (BBO), with a P_(50) of 11.7 BBO; the total gas reserves and resources range from a P_(90) of 53.4 to P_(10) of 313.5 trillion cubic feet (TCF), with a P_(50) of 121.7 TCF. These reserves and resources estimates are much higher than the U.S. Energy Information Administration’s 2011 recoverable resource estimates of 3.35 BBO and 21 TCF. The results of this study provide a critical update on the reserves and resources estimates and their associated uncertainties for the Eagle Ford shale formation of South Texas.
75

A New Global Unconventional Natural Gas Resource Assessment

Dong, Zhenzhen 2012 August 1900 (has links)
In 1997, Rogner published a paper containing an estimate of the natural gas in place in unconventional reservoirs for 11 world regions. Rogner's work was assessing the unconventional gas resource base, and is now considered to be very conservative. Very little is known publicly about technically recoverable unconventional gas resource potential on a global scale. Driven by a new understanding of the size of gas shale resources in the United States, we estimated original gas in place (OGIP) and technically recoverable resource (TRR) in highly uncertain unconventional gas reservoirs, worldwide. We evaluated global unconventional OGIP by (1) developing theoretical statistic relationships between conventional hydrocarbon and unconventional gas; (2) fitting these relationships to North America publically available data; and (3) applying North American theoretical statistical relationships to evaluate the volume of unconventional gas resource of the world. Estimated global unconventional OGIP ranges from 83,300 (P10) to 184,200 (P90) Tcf. To assess global TRR from unconventional gas reservoirs, we developed a computer program that we call Unconventional Gas Resource Assessment System (UGRAS). In the program, we integrated a Monte Carlo technique with an analytical reservoir simulator to estimate the original volume of gas in place and to predict production performance. We used UGRAS to evaluate the probabilistic distribution of OGIP, TRR and recovery factor (RF) for the most productive unconventional gas formations in the North America. The P50 of recovery factor for shale gas, tight sands gas and coalbed methane is 25%, 79% and 41%, respectively. Finally, we applied our global OGIP assessment and these distributions of recovery factor gained from our analyses of plays/formations in the United States to estimate global technically recoverable unconventional gas resource. Global technically recoverable unconventional gas resource is estimated from 43,000 (P10) to 112,000 (P90) Tcf.
76

Evidence of Reopened Microfractures in Production Data of Hydraulically Fractured Shale Gas Wells

Apiwathanasorn, Sippakorn 2012 August 1900 (has links)
Frequently a discrepancy is found between the stimulated shale volume (SSV) estimated from production data and the SSV expected from injected water and proppant volume. One possible explanation is the presence of a fracture network, often termed fracture complexity, that may have been opened or reopened during the hydraulic fracturing operation. The main objective of this work is to investigate the role of fracture complexity in resolving the apparent SSV discrepancy and to illustrate whether the presence of reopened natural fracture network can be observed in pressure and production data of shale gas wells producing from two shale formations with different well and reservoir properties. Homogeneous, dual porosity and triple porosity models are investigated. Sensitivity runs based on typical parameters of the Barnett and the Horn River shale are performed. Then the field data from the two shales are matched. Homogeneous models for the two shale formations indicate effective infinite conductivity fractures in the Barnett well and only moderate conductivity fractures in the Horn River shale. Dual porosity models can support effectively infinite conductivity fractures in both shale formations. Dual porosity models indicate that the behavior of the Barnett and Horn River shale formations are different. Even though both shales exhibit apparent bilinear flow behavior the flow behaviors during this trend are different. Evidence of this difference comes from comparing the storativity ratio observed in each case to the storativity ratio estimated from injected fluid volumes during hydraulic fracturing. In the Barnett shale case similar storativity ratios suggest fracture complexity can account for the dual porosity behavior. In the Horn River case, the model based storativity ratio is too large to represent only fluids from hydraulic fracturing and suggests presence of existing shale formation microfractures.
77

Gas-condensate flow modelling for shale gas reservoirs

Labed, Ismail January 2016 (has links)
In the last decade, shale reservoirs emerged as one of the fast growing hydrocarbon resources in the world unlocking vast reserves and reshaping the landscape of the oil and gas global market. Gas-condensate reservoirs represent an important part of these resources. The key feature of these reservoirs is the condensate banking which reduces significantly the well deliverability when the condensate forms in the reservoir below the dew point pressure. Although the condensate banking is a well-known problem in conventional reservoirs, the very low permeability of shale matrix and unavailability of proven pressure maintenance techniques make it more challenging in shale reservoirs. The nanoscale range of the pore size in the shale matrix affects the gas flow which deviates from laminar Darcy flow to Knudsen flow resulting in enhanced gas permeability. Furthermore, the phase behaviour of gas-condensate fluids is affected by the high capillary pressure in the matrix causing higher condensate saturation than in bulk conditions. A good understanding and an accurate evaluation of how the condensate builds up in the reservoir and how it affects the gas flow is very important to manage successfully the development of these high-cost hydrocarbon resources. This work investigates the gas Knudsen flow under condensate saturation effect and phase behaviour deviation under capillary pressure of gas-condensate fluids in shale matrix with pore size distribution; and evaluates their effect on well productivity. Supplementary MATLAB codes are provided elsewhere on OpenAIR: http://hdl.handle.net/10059/2145.
78

The roles of discourse, legitimacy and power in enabling and hindering institutional change towards sustainability

Etchanchu, Helen 28 September 2016 (has links)
Cette thèse est basée sur trois essais distincts mais interconnectés qui soulignent le rôle important du discours, la légitimité et le pouvoir dans le changement institutionnel vers un développement durable. Dans deux chapitres de ma thèse, j'explore les dynamiques de (de)légitimation du gaz de schiste, en France et en Allemagne. L'exploitation du gaz de schiste par la fracturation hydraulique a déclenché une forte contestation dans ces pays en raison de ses implications socio-économiques, environnementaux et politiques. Le premier essai est une étude de cas comparative des débats publiques sur le de gaz de schiste, qui démontre le rôle important des institutions pour le succès des cadrages mobilisés. Le deuxième essai est une étude de cas portant sur la (de)légitimation des acteurs impliqués dans le débat sur le gaz de schiste français qui propose qu'il y ait une différence fondamentale dans légitimant un problème et légitimant un acteur. Le troisième essai théorique introduit le concept de parentalisme afin de mettre en évidence comment les acteurs contrôlent qui peut participer aux débats. En tout, cette thèse met en lumière comment les débats sur des enjeux sociaux et environnementaux sont influencés par des stratégies discursives en résonance avec le contexte institutionnel et l’identité des acteurs ainsi que par des stratégies de contrôle discursives et non discursives sur qui participe et comment dans la délibération. / This dissertation is based on three separate but interconnected essays which underscore the important roles of discourse, legitimacy and power in fueling or hindering institutional change towards sustainability. In two chapters of my thesis I explore the discursive legitimation dynamics in the contested issue field around shale gas, in France and Germany. The exploitation of shale gas via the hydraulic fracturing (or fracking) technique triggered strong contestation in these countries due to its socio-economic, environmental, and political implications which challenge the energy sector on a global scale. The first essay is a comparative case study of the public shale gas debates which surfaces the important role of institutions in influencing the success of certain arguments over others. The second essay is a single case study focusing on the (de)legitimation of the actors involved in the French shale gas debate which proposes that there is a fundamental difference in legitimating an issue and legitimating an actor. The third theoretical essay introduces the concept of parentalism in order to highlight how actors control who may participate in discursive struggles. On a whole this thesis surfaces how ongoing struggles in contested environmental and social issue fields are shaped by the fit of discursive strategies with the institutional context and contestants’ legitimate identities as well as by actors’ discursive and non-discursive controlling strategies of who participates and how in deliberation.
79

Avaliação da potencialidade do shale gas no Brasil a partir da experiência dos Estados Unidos

Martins, Rhodiney Vaz January 2016 (has links)
Orientador: Prof. Dr. Igor Fuser / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Energia, 2016. / Nos dias atuais a energia tem sido prioridade de vários governos pelo mundo, e vem despertando o interesse de grandes companhias. A energia tem um papel fundamental na sociedade moderna, onde a cada ano o consumo aumenta. A descoberta de enormes reservas de gás não convencional, ou conhecido também como shale gas, vem gerando grande expectativa no mercado mundial de energia. Os EUA têm a maior reserva mundial de shale gas, e são os pioneiros na sua exploração e produção. O Brasil possui a decima maior reserva mundial de shale gas. A sua reserva de shale gas equivale a quinze vezes as reservas de gás convencional do país em 2015 (MME, 2015). Devido a isso pode-se considerar as reservas brasileiras expressivas, o que vem despertando o interesse do país por suas reservas de shale gas. Esta dissertação tem como objetivo analisar o potencial do Brasil para a exploração e produção doshale gas. Para isso, foram consideradas variáveis do Brasil e EUA, como: o estado da arte do mercado regulatório, do domínio tecnológico, qualificação da mão de obra, conhecimento geológico, estrutura de preços, propriedade do solo e subsolo, e por fim as questões ambientais. Procurando assim fazer um paralelo entre essas variáveis dos dois países, verificando se o crescimento da exploração do shale gas americano pode ser repetido no Brasil. Além dessa comparação dos cenários energéticos, foi também levantado depoimentos de especialistas do setor de gás natural do Brasil, por meio de entrevista, contribuindo assim para um debate dos rumos da política energética brasileira. O resultado desta pesquisa mostrou que o Brasil não necessita explorar o shale gas neste momento e ainda não possui um mercado regulatório favorável e mercado interno desenvolvido para o desenvolvimento dos recursos de shale gas. Considerando tanto o aspecto econômico como o ambiental, a conclusão deste trabalho foi de que o Brasil não deve levar adiante a exploração do shale gas, dentro de um tempo previsível. / In the present day energy has been a priority of many Governments around the world, arousing the interest of big companies. Energy has a key role in modern society, where each year the consumption increases. The discovery of vast reserves of unconventional gas, or also known as shale gas comes generating great expectations in the global energy market. The us has the largest world reserve of shale gas, and are pioneers in their exploration and production. The Brazil has the world's largest reserve of decima shale gas. Your reservation of shale gas is equivalent to 15 times the conventional gas reserves in the country in 2015 (MME, 2015). Because of this you can consider the Brazilian reserves, expressive arousing the interest of the country for its reserves of shale gas. This dissertation aims to analyze the potential of Brazil for the exploration and production of shale gas. For this, the variables were considered Brazil and USA, as: the State of the art market's regulatory, technological domain, qualification of the workforce, geological knowledge, price structure, property of the soil and subsoil, and finally environmental issues. Looking for how to make a parallel between these variables of the two countries, noting the growth of shale gas American can be repeated in Brazil. In addition to this comparison of energy scenarios, was also lifted testimonials from industry experts, Brazil's natural gas through the interview, thus contributing to a discussion of the direction of the Brazilian energy policy. The result of this research showed that Brazil does not need to explore shale gas right now and still does not have a favourable regulatory and market internal market developed for resource development of shale gas. Considering both the economic aspect as the environmental, the conclusion of this work was that Brazil should not carry out the exploitation of shale gas, within a predictable time.
80

Shale Gas & Oil : a nova dinâmica energética mundial e as perspectivas para o Brasil

Cambi, Rui Cesar January 2017 (has links)
Orientador: Prof. Dr. Igor Fuser / Dissertação (mestrado) - Universidade Federal do ABC. Programa de Pós-Graduação em Energia, 2017. / A premente necessidade de energia é cada vez mais atual na sociedade contemporânea. O seu uso está correlacionado aos costumes, estágio de desenvolvimento e ao grau de industrialização do país. A busca por novos recursos energéticos é questão primordial para o bem-estar das pessoas e para a expansão econômica dos países. A descoberta de importantes recursos energéticos, denominados hidrocarbonetos não convencionais tais como: óleo pesado e ultrapesado, areias betuminosas, óleo encontrado em águas profundas e ultraprofundas como o pré-sal e o shale gas & oil que está disseminado de forma homogênea pelo mundo todo, vem chamando a atenção de vários países. Os EUA, um dos maiores importadores de petróleo e gás do mundo, são portadores de vastas reservas de shale gas & oil e possuem conhecimento geológico e tecnologia adequada. Isso tornou o país o precursor da exploração desse energético no mundo. A produção dos Estados Unidos vem crescendo significativamente, reduzindo sua dependência de petróleo e gás importado, provocando abundância no mercado global, o que resulta em queda de preço do petróleo e gás, alterando a geopolítica da energia mundial. O Brasil, no contexto mundial, possui reservas expressivas de não convencionais, sendo a 10ª maior reserva do mundo. É crescente a necessidade de energia pela sociedade brasileira e o país vem demonstrando interesse em explorar esses energéticos. Esta dissertação tem como objetivo analisar as perspectivas mundiais de exploração desses hidrocarbonetos não convencionais à luz da experiência dos EUA, analisando o panorama brasileiro para futuras explorações. Este estudo mostrou como resultado que o Brasil terá dificuldades de replicar a exploração do shale gas & oil, como ocorreu nos EUA. / The pressing need for energy is increasingly present in contemporary society. Energy consumption is correlated with their customs, the stage of development and the degree of industrialization of the country. The search for new energy resources is a key issue for people's well-being and for the economic expansion of countries. The discovery of important energy resources, called unconventional hydrocarbons shale gas & oil, spread democratically around the world, has drawn the attention of several countries. The US, one of the largest importers of oil and gas in the world, carry vast reserves of shale gas & oil and has geological knowledge and appropriate technology. This made the country the precursor of the exploitation of this energy in the world. US production has been growing significantly, reducing its dependence on imported oil and gas, sparking global market abundance, resulting in falling oil and gas prices, shifting global energy geopolitics. Brazil in the world context has significant reserves, being the 10th largest reserve in the world. There is a growing need for energy by Brazilian society. The country has been showing interest in exploiting these energy sources. The objective of this dissertation is to analyze the global prospects for exploration of these unconventional hydrocarbons in the light of the US experience, to evaluate possible interferences in the geopolitics of energy at global level, ascertaining socioeconomic and environmental issues, knowledge to support future development studies on Brazilian soil.

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