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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.
101

USA’s policies on fracking

Shrivastava, Bulbul January 2017 (has links)
A research report submitted to the Faculty of Humanities, University of the Witwatersrand, Johannesburg, in partial fulfilment of the requirements for the degree of Master of Arts(International Relations), 2017 / In the past decade, the United States’ oil and gas industry experienced an extraordinary boom, due to shale gas. Shale gas accounted for only 1.6% of total US natural gas production in 2000, 4.1% by 2005, and an astonishing 23.1% by 2010. This remarkable growth has spurred interest in exploring for shale gas resources elsewhere. The purpose of the study is how the rise of fracking in the USA has impacted its foreign policy towards climate change. An exploratory qualitative method, known as process-tracing was used, with the aim of providing evidence-based literature in order to explore the change in the USA’s domestic energy and climate policies; as well to see the change in its stance on climate change on the international platform. Some of the key concluding findings relate to the Obama Administration’s championing of the Clean Energy Act. / XL2018
102

Aspectos regulatórios e institucionais do desenvolvimento de gás não convencional: uma análise comparativa entre Brasil e Estados Unidos / Regulatory and institutional aspects of unconventional gas development: a comparative analysis between Brazil and the United States of America

Araújo, Renata Rodrigues de 29 July 2016 (has links)
Esta tese avaliou se o Brasil, sob a perspectiva regulatória, encontra-se preparado para iniciar localmente o desenvolvimento de gás de folhelho, principal fonte de gás não convencional. Para tal, adotou como metodologia uma análise comparativa entre a legislação do setor de gás natural dos EUA e do Brasil, com foco na regulamentação das operações de fraturamento hidráulico, buscando evidenciar e contextualizar os principais fatores de sucesso da experiência estadunidense. Na realização dessas investigações foram utilizados diversos conceitos da Política Ambiental que podem ser empregados na elaboração de normas e condutas voltadas para o gás não convencional. Pautada no resultado dessas análises, que apontou a necessidade de estudos ambientais, sociais e econômicos mais aprofundados, apresentou-se como principal recomendação uma proposta de Avaliação Ambiental Estratégica (AAE). Tal ferramenta pode orientar a decisão do governo em relação à exploração de hidrocarbonetos não convencionais no Brasil, bem como auxiliar o país na obtenção de uma licença social para operar e na criação das condições necessárias para explorar seus possíveis recursos de gás de folhelho de maneira segura e responsável. / This thesis assesses whether Brazil, from the regulatory point of view, is ready to start a local production of shale gas, the main source of unconventional gas. For this purpose, the study conducted a comparative analysis of the primary laws regulating of oil and gas exploration and production activities in the USA and Brazil, focusing on the hydraulic fracturing operations, in order to determine and contextualize the major factors of success for the American shale gas experience. Several approaches of Environmental Policy that can be used in the development of standards and rules for unconventional gas were used. The results indicated the need for additional environmental, social and economic studies. Therefore, a Strategic Environmental Assessment (SEA) proposal was the main recommendation. This tool may guide the government\'s decision about the unconventional resources production in Brazil, help the county to achieve a social license to operate and meet the conditions required to explore its potential shale gas resources.
103

A New Method for History Matching and Forecasting Shale Gas/Oil Reservoir Production Performance with Dual and Triple Porosity Models

Samandarli, Orkhan 2011 August 1900 (has links)
Different methods have been proposed for history matching production of shale gas/oil wells which are drilled horizontally and usually hydraulically fractured with multiple stages. These methods are simulation, analytical models, and empirical equations. It has been well known that among the methods listed above, analytical models are more favorable in application to field data for two reasons. First, analytical solutions are faster than simulation, and second, they are more rigorous than empirical equations. Production behavior of horizontally drilled shale gas/oil wells has never been completely matched with the models which are described in this thesis. For shale gas wells, correction due to adsorption is explained with derived equations. The algorithm which is used for history matching and forecasting is explained in detail with a computer program as an implementation of it that is written in Excel's VBA. As an objective of this research, robust method is presented with a computer program which is applied to field data. The method presented in this thesis is applied to analyze the production performance of gas wells from Barnett, Woodford, and Fayetteville shales. It is shown that the method works well to understand reservoir description and predict future performance of shale gas wells. Moreover, synthetic shale oil well also was used to validate application of the method to oil wells. Given the huge unconventional resource potential and increasing energy demand in the world, the method described in this thesis will be the "game changing" technology to understand the reservoir properties and make future predictions in short period of time.
104

Production Performance Analysis Of Coal Bed Methane, Shale Gas, Andtight Gas Reservoirs With Different Well Trajectories And Completiontechniques

Erturk, Mehmet Cihan 01 February 2013 (has links) (PDF)
The large amount of produced oil and gas come from conventional resources all over the world and these resources are being depleted rapidly. This fact and the increasing oil and gas prices force the producing countries to find and search for new methods to recover more oil and gas. In order to meet the demand, the oil and gas industry has been turning towards to unconventional oil and gas reservoirs which become more popular every passing day. In recent years, they are seriously considered as supplementary to the conventional resources although these reservoirs cannot be produced at an economic rate or cannot produce economic volumes of oil and gas without assistance from massive stimulation treatments, special recovery processes or advanced technologies. The vast increase in demand for petroleum and gas has encouraged the new technological development and implementation. A wide range of technologies have been developed and deployed since 1980. With the wellbore technology, it is possible to make use of highly deviated wellbores, extended reach drilling, horizontal wells, multilateral wells and so on. All of the new technologies and a large number of new innovations have allowed development of increasingly complex economically marginal fields where shale gas and coal bed methane are found. In this study, primary target is to compare different production methods in order to obtain better well performance and improved production from different types of reservoirs. It is also be given some technical information regarding the challenges such as hydraulic fracturing and multilateral well configuration of the unconventional gas reservoir modeling and simulation. With the help of advances in algorithms, computer power, and integrated software, it is possible to apply and analyze the effect of the different well trajectories such as vertical, horizontal, and multilateral well on the future production performance of coal bed methane, shale gas, and tight gas reservoirs. A commercial simulator will be used to run the simulations and achieve the best-case scenarios. The study will lead the determination of optimum production methods for three different reservoirs that are explained above under the various circumstances and the understanding the production characteristic and profile of unconventional gas systems.
105

A New Series of Rate Decline Relations Based on the Diagnosis of Rate-Time Data

Boulis, Anastasios 14 January 2010 (has links)
The so-called "Arps" rate decline relations are by far the most widely used tool for assessing oil and gas reserves from rate performance. These relations (i.e., the exponential and hyperbolic decline relations) are empirical where the starting point for their derivation is given by the definitions of the "loss ratio" and the "derivative of the loss ratio", where the "loss ratio" is the ratio of rate data to derivative of rate data, and the "derivative of the loss ratio" is the "b-parameter" as defined by Arps [1945]. The primary goal of this work is the interpretation of the b-parameter continuously over time and thus the better understanding of its character. As is shown below we propose "monotonically decreasing functional forms" for the characterization of the b-parameter, in addition to the exponential and hyperbolic rate decline relations, where the b-parameter is assumed to be zero and constant, respectively. The proposed equations are as follow: b(t)=constant (Arps' hyperbolic rate-decline relation), []tbbtb10exp)(-bt= (exponential function), (power-law function), 10)(btbtb=)/(1)(10tbbtb+= (rational function). The corresponding rate decline relation for each case is obtained by solving the differential equation associated with the selected functional for the b-parameter. The next step of this procedure is to test and validate each of the rate decline relations by applying them to various numerical simulation cases (for gas), as well as for field data cases obtained from tight/shale gas reservoirs. Our results indicate that b-parameter is never constant but it changes continuously with time. The ultimate objective of this work is to establish each model as a potential analysis/diagnostic relation. Most of the proposed models yield more realistic estimations of gas reserves in comparison to the traditional Arps' rate decline relations (i.e., the hyperbolic decline) where the reserves estimates are inconsistent and over-estimated. As an example, the rational b-parameter model seems to be the most accurate model in terms of representing the character of rate data; and therefore, should yield more realistic reserves estimates. Illustrative examples are provided for better understanding of each b-parameter rate decline model. The proposed family of rate decline relations was based on the character of the b-parameter computed from the rate-time data and they can be applied to a wide range of data sets, as dictated by the character of rate data.
106

Aspectos regulatórios e institucionais do desenvolvimento de gás não convencional: uma análise comparativa entre Brasil e Estados Unidos / Regulatory and institutional aspects of unconventional gas development: a comparative analysis between Brazil and the United States of America

Renata Rodrigues de Araújo 29 July 2016 (has links)
Esta tese avaliou se o Brasil, sob a perspectiva regulatória, encontra-se preparado para iniciar localmente o desenvolvimento de gás de folhelho, principal fonte de gás não convencional. Para tal, adotou como metodologia uma análise comparativa entre a legislação do setor de gás natural dos EUA e do Brasil, com foco na regulamentação das operações de fraturamento hidráulico, buscando evidenciar e contextualizar os principais fatores de sucesso da experiência estadunidense. Na realização dessas investigações foram utilizados diversos conceitos da Política Ambiental que podem ser empregados na elaboração de normas e condutas voltadas para o gás não convencional. Pautada no resultado dessas análises, que apontou a necessidade de estudos ambientais, sociais e econômicos mais aprofundados, apresentou-se como principal recomendação uma proposta de Avaliação Ambiental Estratégica (AAE). Tal ferramenta pode orientar a decisão do governo em relação à exploração de hidrocarbonetos não convencionais no Brasil, bem como auxiliar o país na obtenção de uma licença social para operar e na criação das condições necessárias para explorar seus possíveis recursos de gás de folhelho de maneira segura e responsável. / This thesis assesses whether Brazil, from the regulatory point of view, is ready to start a local production of shale gas, the main source of unconventional gas. For this purpose, the study conducted a comparative analysis of the primary laws regulating of oil and gas exploration and production activities in the USA and Brazil, focusing on the hydraulic fracturing operations, in order to determine and contextualize the major factors of success for the American shale gas experience. Several approaches of Environmental Policy that can be used in the development of standards and rules for unconventional gas were used. The results indicated the need for additional environmental, social and economic studies. Therefore, a Strategic Environmental Assessment (SEA) proposal was the main recommendation. This tool may guide the government\'s decision about the unconventional resources production in Brazil, help the county to achieve a social license to operate and meet the conditions required to explore its potential shale gas resources.
107

Freshwater invertebrate assemblages of the Eastern Cape Karoo region (South Africa) earmarked for shale gas exploration

Mabidi, Annah January 2017 (has links)
The Eastern Cape Karoo region is semi-arid with highly variable rainfall. This variability in rainfall sustains a mosaic of surface freshwater bodies that range from permanently to temporarily inundated. These waterbodies provide habitats for diverse invertebrate assemblages. The imminent hydraulic fracturing for shale gas has a potential to modify the water regime, with particular risk of salinisation. Accumulation of salts in freshwater wetlands results in loss of biodiversity, as invertebrate species shift from salt intolerant to salt tolerant species. This study therefore aims to expand on existing knowledge and provide new information on the distribution, diversity and structure of macroinvertebrate assemblages associated with various freshwater bodies in the region prior to shale gas exploration. Limnological and ecological aspects of thirty-three waterbodies (rivers, dams and depression wetlands) were investigated between November 2014 and March 2016. An experimental study on the effects of salinity on hatching success of branchiopod resting eggs was also included in the research. Rivers were characterised by high conductivity and depression wetlands by high turbidity, while dams had relatively higher pH than the other two waterbody types. In terms of global phosphorus interpretation guidelines, the results indicate that freshwater systems in the study region are predominantly eutrophic, indicating that agricultural run-off, particularly from livestock dung (goats, cattle and sheep), is an important source of phosphorus in the freshwater systems studied. Our results revealed new distribution records for branchiopod crustaceans in the Eastern Cape region, including the first record of Laevicaudata. Results showed that the sampled variables were unable to explain the variation in physicochemistry and invertebrate assemblage of several sites. Waterbody type, whether a depression wetland or a river, was the only factor that consistently showed an effect on the composition of both physicochemical data and invertebrate data. Depression wetlands ranged from completely bare to being extensively covered by macrophytes. Therefore, the effect of macrophyte cover in structuring macroinvertebrate assemblages was the focus of further investigation. The results indicated that the macrophyte cover gradient had little influence on the structure of the invertebrate assemblages in the depression wetlands, while only the presence/absence of vegetation significantly influenced the structure of the invertebrate assemblages in these systems. Surface area, dissolved inorganic nitrogen and pelagic chlorophyll-a were the environmental variables that best explained the variation in the macroinvertebrate assemblages among the sites. However, the differences in macroinvertebrate richness, abundance and distribution patterns among sites were only weakly influenced by local and regional environmental factors. These findings suggest that invertebrate in temporary wetland systems are adapted to the highly variable nature of temporary habitats, thus the influence of local variables is negligible. Results of the experimental study, on the effect of salinity on hatching success of branchiopod resting eggs, revealed that hatchling abundance and diversity of large branchiopods was significantly reduced at salinities of 2.5 g L−1 and above. Salt-tolerant taxa such as Copepoda and Ostracoda were the only ones to emerge in the highest salinity of 10 g L−1. Thus, should the region continue to experience increasing aridity and possible shale gas development, which all aggravate the salinisation problem, severe loss of branchiopod diversity (Anostraca, Laevicaudata, Spinicaudata and Notostraca) is likely to occur. This may lead to considerable decline in invertebrate diversity in the region, with cascading effects on food webs and ecosystem functions. The findings of this study can potentially be used in comparative studies on wetland invertebrate ecology in other semi-arid regions and in the formulation of policy and strategies for biodiversity conservation.
108

Břidlicový plyn a střety (veřejných) zájmů (Na příkladu lokalit Trutnovska a Berounska) / Shale gas and conflict of (public) interests (Based on the example of Trutnovsko and Berounsko)

Hellerová, Šárka January 2014 (has links)
The goal of this thesis is to examine the term of public interest within the framework of the 'shale gas' issue in the Czech Republic. The theoretical section is divided into two basic parts. The first part defines the term public interest from the point of view of political science, sociology and economy. The second one describes the issue of shale gas extraction in global context. The examination is focused on the context of administrative procedures defining the prospecting exploration area of unconventional hydrocarbon resources in the Trutnov region and around the Berounka River The intention of private companies to extract shale gas in the Czech Republic caused a big discussion. In its core there is the dispute between the economic development of the country connected with energy security on one hand and the environment protection on the other. Within this debate the term public interest appears in many different contexts. The way it is used by the people involved and their interests are described through interviews with them and analysis of the gained material.
109

Effect of Hydraulic Fracturing Fluid Viscosity on Stimulated Reservoir Volume for Shale Gas Recovery / シェールガス生産のための亀裂造成にもたらす水圧破砕流体の粘度の影響

Bennour, Ziad 23 March 2017 (has links)
京都大学 / 0048 / 新制・課程博士 / 博士(工学) / 甲第20338号 / 工博第4275号 / 新制||工||1662(附属図書館) / 京都大学大学院工学研究科社会基盤工学専攻 / (主査)教授 石田 毅, 教授 林 為人, 准教授 奈良 禎太 / 学位規則第4条第1項該当 / Doctor of Philosophy (Engineering) / Kyoto University / DFAM
110

Uncertainty, Public Engagement and Trust: Shale Gas Policy Learning and Change in New Brunswick (2007-2017)

Nourallah, Laura 26 May 2023 (has links)
This dissertation examines a major policy change in the context of energy decision-making for shale gas development in the province of New Brunswick, Canada. After a long series of public engagement exercises aimed at regulating and promoting the safe development of shale gas resources in New Brunswick, the provincial government implemented a moratorium on hydraulic fracturing in 2014 and extended it indefinitely in 2016. The dissertation is interested in how policy-oriented learning may have influenced this policy change from both an empirical and a theoretical perspective. Theoretically, in line with recent scholarship on policy learning, this study trains its sites on the nature of policy learning and how it may influence change. To this end, the dissertation is grounded in the Advocacy Coalition Framework (ACF), a theoretical approach with (i) clearly defined mechanisms of learning, and (ii) significant application to resource development and to case studies of resource development in jurisdictions across North America and globally. The study builds on the ACF by proposing a conception of learning drawing on post-positivist literature. The study argues that learning is too narrowly focused on policy elites in the ACF and should be expanded to consider the role of non-traditional actors. The analysis questions the notion that learning can be isolated to rational and technical understandings amongst policy elites, and aims to integrate interactive knowledge into the analysis as a fundamental component of learning. The research aims to contextualize learning and understand the factors that shape policy learning and policy change. The dissertation focuses on the role of three factors - public engagement, uncertainty and trust - in shaping policy actors' learning. Empirically, the study examines the case of New Brunswick between 2007 and 2017. The province undertook multiple public engagement exercises regarding shale gas development in the context of unknown risks and uncertainty associated with the practice of hydraulic fracturing, an emerging technology that enabled the production of shale gas on a large scale. Two major coalitions emerged that advocated for and against shale development in the province, with the dominant pro-development coalition asserting that shale gas could proceed safely through stringent regulation. Through documentary analysis, interviews and a media analysis, the research reveals that interactive knowledge was a key component of how people learned in the case. The anti-shale coalition in New Brunswick brought its lived experience - notably its lack of trust in public authorities to successfully regulate fracking - to bear on decision-making, and was able to undermine and question the pro-development coalition's position that the risks associated with hydraulic fracturing could be managed. The anti-shale coalition mobilized this knowledge through the government's public engagement exercises and successfully contested the dominant coalition's beliefs. Fundamentally, the study demonstrates that public engagement, uncertainty and trust are three key factors that can shape policy learning and change.

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