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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.
161

Tundra vegetation recovery on 30 year-old seeded and unseeded drilling mud sumps in the Mackenzie River Delta region, NWT

Wunderlich, Nicole Bettina 08 April 2010
Oil and gas exploration conducted in the 1970s left behind a legacy of abandoned well sites in the Mackenzie Delta region of northern Canada, including several in the Kendall Island Migratory Bird Sanctuary and surrounding areas. Evidence of 30 year-old well sites is present in the form of drilling mud sumps, which are mounds of disturbed tundra that contain frozen drilling-wastes. One to two years after the wells were decommissioned some of the sites were seeded with non-native grass species and fertilized to test whether these treatments could accelerate vegetation recovery and prevent erosion. The main objective of this research was to examine the long-term impact of post-disturbance seeding treatments on the vegetation recovery of drilling mud sumps.<p> Surveys of vegetation composition and environmental conditions at 12 sump sites (6 seeded and 6 unseeded) showed that, after over 30 years of recovery, seeded sumps in the Mackenzie Delta did not significantly differ from those left for natural recovery. However, seeded and previously introduced grasses <i>Festuca rubra</i> and <i>Poa pratensis</i> were found on both seeded and unseeded sumps. The undisturbed surrounding tundra seems to be resistant to invasion by these introduced grasses. However, these species could become invasive in the future, particularly in the context of warming in the North and increasing anthropogenic disturbance. The results of this study contribute valuable information on the long-term effects of revegetation treatments that is critical for making informed management decisions about the rehabilitation of industrial disturbances in the Arctic.
162

Tundra vegetation recovery on 30 year-old seeded and unseeded drilling mud sumps in the Mackenzie River Delta region, NWT

Wunderlich, Nicole Bettina 08 April 2010 (has links)
Oil and gas exploration conducted in the 1970s left behind a legacy of abandoned well sites in the Mackenzie Delta region of northern Canada, including several in the Kendall Island Migratory Bird Sanctuary and surrounding areas. Evidence of 30 year-old well sites is present in the form of drilling mud sumps, which are mounds of disturbed tundra that contain frozen drilling-wastes. One to two years after the wells were decommissioned some of the sites were seeded with non-native grass species and fertilized to test whether these treatments could accelerate vegetation recovery and prevent erosion. The main objective of this research was to examine the long-term impact of post-disturbance seeding treatments on the vegetation recovery of drilling mud sumps.<p> Surveys of vegetation composition and environmental conditions at 12 sump sites (6 seeded and 6 unseeded) showed that, after over 30 years of recovery, seeded sumps in the Mackenzie Delta did not significantly differ from those left for natural recovery. However, seeded and previously introduced grasses <i>Festuca rubra</i> and <i>Poa pratensis</i> were found on both seeded and unseeded sumps. The undisturbed surrounding tundra seems to be resistant to invasion by these introduced grasses. However, these species could become invasive in the future, particularly in the context of warming in the North and increasing anthropogenic disturbance. The results of this study contribute valuable information on the long-term effects of revegetation treatments that is critical for making informed management decisions about the rehabilitation of industrial disturbances in the Arctic.
163

Feasibilty Study Of Sequestration Of Carbon Dioxide In Geological Formations

Gultekin, Cagdas 01 January 2011 (has links) (PDF)
Although there are some carbon capture and storage (CCS-CO2 sequestration) projects in all over the world, feasibility problems exist due to the high economical issues. The aim of this study is to evaluate the feasibility of a potential CCS project where the source of CO2 is Afsin Elbistan Thermal Power Plant. Selection of candidate sites in the vicinity of Diyarbakir, Batman and Adiyaman regions depends on sequestration criteria. According to sequestration criteria, CCS can be applied to &Ccedil / aylarbasi mature oil field, Midyat saline aquifer and Dodan CO2 gas field. Disposing of CO2 from the source of Afsin Elbistan Thermal Power Plant is analyzed by pipeline and tanker. CO2 capturing technologies are determined from published literature. CO2 transportation can be applied by pipeline or tanker. CO2 transportation cost by pipeline and tanker are compared. It has been calculated that, transportation by pipeline is more economical compared to tanker transportation. It is further found that the number of boosting pump stations, the length of the pipeline and CO2 mass flow rate are the issues that alter the economical aspect in the pipeline transportation. The transportation costs by tankers depend on fuel cost, distance, tanker storage capacity, pin-up cost and CO2 storage facilities. The final part of CCS project is injection and storage of CO2 to the candidate areas. Reservoir parameters which are reservoir temperature, viscosity, permeability, reservoir pressure, reservoir thickness, CO2 density mass flow rate and injection pipe diameter determine the number and cost of the injection wells.
164

Evolution Of Oil Politics In Iraq From The 20th Century Onwards

Akyuz, Zeynep Ceren 01 September 2011 (has links) (PDF)
The objective of this thesis is to analyze the Iraqi politics of oil in the period from 20 th century onwards. Within this regard, while &ldquo / rentier state&rdquo / conception is generally put under consideration to understand the state&rsquo / s centrality in political, economic and social spheres of oil &ndash / producing countries, contrary to this conventional approach,this thesis argues that the key to all achievements and all failures of Iraqi state is related to the status of oil in Iraq&rsquo / s engagement with the superpowers and the attractiveness of Iraqi oil for other external actors like international non-state actors and multinational companies. In the first instance, the engagement of Britain and later on, the inclusion of the U.S to the national, regional and international affairs of Iraq are discussed within the boundaries of the aforementioned argument. The role of oil in the creation of the state, in its relations with neighbour countries and in relations conducted with the super powers of the international system is analyzed. Within this context, in the aftermath of the September 11, the U.S&rsquo / s intense desires for regime change in Iraq is analyzed to reveal that the main motivation behind the invasion of Iraq in 2003 is related with the country&rsquo / s vast oil resources. In the similar vein, the developments in the post- invasion period are analyzed to indicate the prevailing prominent role of oil. Eventually, this thesis states that even though changes and continuities occur in the course of time and accordingly divergences and convergences exist in the implementations of the Iraqi state, the issue of guaranteeing the flow of oil at reasonable price has remained in the focal point of the external interventions to Iraq.
165

Estimating attenuation properties of bentonite layer in Cut Bank oil field, Glacier County, Montana

Karakurt, Necdet 12 April 2006 (has links)
Acquisition and interpretation of 3-D seismic data led DeAngelo and Hardage (2001) to describe the channel system in the south central Cut Bank area in Glacier County, Montana. The presence of a low velocity layer called Bentonite was also discovered in the area with the help of well-logs. Bentonite is a volcanic ash, which lies on both sides of the channel system and is absent within the channel. DeAngelo and Hardage (2001) shot a vertical seismic profiling (VSP) survey at well # 54-8 to analyze the formation structure in depth, since seismic signals around the reservoir area were unclear in the 3-D survey. This research attempts to estimate the attenuation properties of the Bentonite layer in the Cut Bank oil field. VSP data is processed for velocity information and estimation of seismic Q using the spectral ratios method (SRM). The SRM theoretically assumes that the propagating signal is a plane seismic wave traveling vertically from one point to another in a homogeneous model. The amplitudes at the start and end points are known and relate to each other with the attenuation coefficient in a frequency range. The relation between the seismic amplitudes at z distance from each other can be expressed as a linear function of frequency after a few modifications. SRM uses the linearity of the logarithmic ratio of the seismic amplitudes over a frequency range. In theory, ratios plotted against a frequency range must produce a flat line. However, in practice, the logarithmic ratios are expected to draw an approximate line (curve), where some of the data points deviate from the origin of the line. Thus fitting a line to the ratios curve and calculating the slope of this curve are necessary. Slope of the curve relates to the seismic attenuation coefficient and further to the seismic Q. The SRM results suggest that Bentonite may have a Q value as low as 5. This highly attenuative and thin (20 to 40 feet throughout the south central Cut Bank Unit) layer alters seismic signals propagating through it. A thorough analysis of the amplitude spectra suggests that seismic signals dramatically lose their energy when they pass through Bentonite. Low energy content of the signals below the Bentonite layer highlights that the recovery of the seismic energy is less likely despite the presence of multiples, which are known to affect the seismic signals constructively. Therefore, separation of reflected events is a greater challenge for the thin reservoir sand units lying underneath the Bentonite layer. Thus the Bentonite layer in the Cut Bank oil field has to be taken seriously and data processing should be done accordingly for better accuracy.
166

Econometric analysis of the impact of market concentration on prices in the offshore drilling rig market

Onwuka, Amanda Chiderah 16 February 2011 (has links)
This thesis presents an econometric methodology for analyzing the impact of market concentration (HHI) on the day rate prices paid by E&P operators for the lease of drilling rigs. It is an extension of the work of Lee (2008), ‘Measuring the Impact of Concentration in the Drilling Rig Market’. Specifically, the work entailed using a more detailed time series data than was initially used (quarterly), analyzing impact of concentration on day rate prices by water depth specification of drilling rigs, and accounting for the impact of autocorrelation on the analysis. The results for jack-ups, without adjustment for autocorrelation, supported the results of the prior study i.e. showing that increase in HHI causes rig day rate price increase. However, the results for semi-submersibles was inconclusive as it varied from region to region and also was contrary to the assumptions of positive relationships between HHI and day rate prices made in this study. These results imply that market concentration caused both price increase and decrease within the industry depending on whether it increased market power or increased cost efficiency and technological ability. / text
167

Community engagement as conflict prevention: understanding the social license to operate

Knih, Dejana 06 December 2012 (has links)
This thesis examines community engagement as a form of conflict prevention in order to obtain the social license to operate (SLO) in Alberta’s oil and gas industry. It does this by answering the question: what are the key elements of the Social License to Operate and how can these elements be applied to community engagement/consultation in a way that prevents conflicts in Alberta’s oil and gas industry? The underlying assumption of this thesis is that building good relationships and working collaboratively functions as a form of conflict prevention and that this in turn leads to the SLO. This thesis outlines the key features of both successful community engagement and of the SLO, to provide a guideline for what is needed to obtain the SLO. Data was collected from semi-structured interviews and through a literature review. The data analysis concluded that there are direct parallels between the key elements of effective community engagement and the key elements of the SLO as identified in the interviews. These parallels are: knowing the community, addressing community needs, corporate social responsibility, relationship building, follow through and evidence for what has been done, executive buy-in, excellent communication, and open dialogue, all within a process which is principled (there is trust, understanding, transparency and respect), inclusive, dynamic, flexible, ongoing, and long-term. Moreover, the key elements of effective community engagement and of the SLO identified in the interviews also overlapped with those found in the literature review, with only one exception. The literature review explicitly named early involvement as a key element of both effective community engagement and the SLO, whereas the interview participants only explicitly indicated it as a key factor of community engagement and implied it to be a key element of the SLO. / Graduate
168

Experimental Testing of an Electrical Submersible Pump Undergoing Abrasive Slurry Erosion

Saleh, Ramy Moaness M 03 October 2013 (has links)
The Electrical Submersible Pump (ESP) manufactured by Baker Hughes, model no. WJE-1000 is designed for wells that are expected to have a high content of abrasive solids. It is a mixed flow, tandem compression type pump. Although the erosion of the pump diffuser and impeller stages are significant, the ESP study shows that the most sever failure is due to components that affect the pump’s rotor dynamics such as radial bearings and impeller seals when eroded with 100 mesh sand. Erosion of these seals will result in an internal leakage that can significantly affect stage pressure rise, efficiency, power consumption, vibration, pump life and running cost. The erosion study utilizing 100 mesh fracture sand at 0.2% concentration, with the pump operating at 3600 RPM, 40 PSI intake pressure, 1150 GPM for over 117 hours comparisons are made to the pump’s baseline performance. Measurements of the rotor bearings, impeller seals and their corresponding stators showed that the wear patterns generally increase with time and differ by location. Stage 1 bearings and seals suffered the least amount of erosion and stage 3 rotor components suffered the most erosion. The maximum change in stage 3 bearing clearances was 223% and the maximum change in stage 3 impeller seal clearances was 300%. Performance wise the total pump efficiency dropped by 6.77%, the total pressure rise dropped by 6.3%, the pump’s best efficiency point decreased by 0.78%, and the power consumption increased by 0.49%. Pump vibration patterns also changed with time and by location. The maximum shaft orbit diameter was at stage 3 and it grew 643% in diameter after 117 hours of erosion. The waterfall plots of the pump’s ramp up changed significantly with time. After 117 hours at 3600 RPM, sub-synchronous oscillations at 67% of the synchronous speed dominated the amplitude peaks showing that the rotor vibration locked with the rotor’s first natural frequency at around 2500 RPM. After 117 hours, another sub-synchronous started showing a peak at the rotor’s second natural frequency at 1500 RPM.
169

Navegar é preciso, educar também é preciso: as contradições teórico-metodológicas do Projeto de Educação Ambiental dos Trabalhadores (PEAT), no âmbito do licenciamento ambiental para atividades de E&P offshore. / Navigation is necessary, education is also necessary: the theoretical-methodological contradictions found in the Environmental Education Project for Workers (PEAT), under the environmental licensing process for E&P activities.

Catarina de Melo Peixoto 26 March 2013 (has links)
O presente estudo traz para discussão as ações educativas destinadas aos trabalhadores, no âmbito do licenciamento ambiental das atividades de perfuração e exploração de petróleo e gás offshore - à luz dos referenciais teórico metodológicos de uma Educação Ambiental (EA) crítica. Muito embora as pesquisas em EA no Brasil tenham alcançado um elevado grau de maturidade, produzindo reflexões profícuas e embasando a elaboração tanto de diretrizes quanto instruções normativas; ainda hoje, importantes eixos de atuação e públicos de interesse específicos - a exemplo de trabalhadores alocados em unidades de perfuração, produção e embarcações de apoio - carecem de uma reflexão aprofundada que questione tanto o substrato epistemológico empregado quanto o tipo de práxis educativa que vem sendo construída. Neste sentido o estudo analisa o Projeto de Educação Ambiental dos Trabalhadores (PEAT) elaborado por duas grandes empresas de consultoria, sediadas no Rio de Janeiro, com o objetivo de avaliar em que medida seus projetos pedagógicos incorporam os princípios da EA instituídos pela Política Nacional de Educação Ambiental. Ademais são observados os pontos críticos (contradições) para a operacionalização do Projeto e o embate entre discursos antagônicos, que buscam a hegemonia material e simbólica do campo da EA, tomando por base a análise de discurso a partir de entrevistas realizadas com os principais atores envolvidos na elaboração do PEAT: empreendedor-consultoria-órgão ambiental. Como resultado observamos: (i) uma deficiência (por parte das consultorias) em incorporar os fundamentos teóricos da EA ao PEAT submetido para aprovação do órgão ambiental licenciador; (ii) uma inadequação das concepções metodológicas do PEAT, com consequentes advertências por parte do órgão ambiental e (iii) o engendramento de uma situação de incoerência na qual o órgão ambiental licenciador aprova um documento escrito (PEAT submetido) e desaprova as práticas educativas por este desencadeadas. / This study starts the discussion of educational actions designed for workers, under the environmental licensing process of exploration and production of oil and gas from the perspective of the theoretical methodological references of critical Environmental Education (EE). Even though research in EE in Brazilhas reached an elevated degree of maturity, producing fruitful reflections and providing basis for the elaboration of guidelines as well as normative instructions; even today, important areas of action and target publics of specific interests as is exemplified by workers allocated in drilling and production units and supply vessels lack a deeper reflection that questions not only the epistemological basis used but also the kind of educational praxis that is being constructed. In this way, this study analyses the Environmental Education Project for Workers (PEAT) elaborated by two large consulting companies, based in Rio de Janeiro, so as to evaluate in what way their pedagogical projects incorporate the principles of EE put forth by the National Environmental Education Policy. Critical points (contradictions) for the operationalization of the Project are also observed as well as the shock between conflicting discourses that look for material and symbolic hegemony in the EE field, by analyzing the discourse from interviews carried out with the main actors involved in the elaboration of the PEAT: the company consulting company environmental agency. As a result, we see: (i) a deficiency (on the part of the consulting companies) in incorporating the theoretical foundations of EE into the PEAT submitted for approval by the environmental agency responsible for the licensing process; (ii) inadequate methodological conceptions of the PEAT, with subsequent warnings from the environmental agency and (iii) the creation of a situation of incoherencies in which the environmental agency approves a written document (the submitted PEAT) and disapproves of the educational practices that this document propagates.
170

Vulnerabilidade socioambiental dos manguezais de Garapuá, Cairu/BA frente à inserção da indústria petroleira. / Socioenvironmental vulnerability of Garapuá mangroves relative to the insertion of the oil industry

Júlio Augusto de Castro Pellegrini 23 September 2010 (has links)
Fundação de Amparo à Pesquisa do Estado do Rio de Janeiro / Manguezais são ecossistemas marinhos costeiros que ocorrem nas regiões tropicais e subtropicais do globo. A associação desses ambientes a formações recifais é restrita, particularmente no Brasil, onde se destaca a ilha de Tinharé, na costa sul do estado da Bahia, não só pela ocorrência desse sistema manguezal-recifes, mas também pelo desenvolvimento estrutural da floresta e pela atividade produtiva de mariscagem exercida pela população do povoado de Garapuá. Apesar da proximidade de Morro de São Paulo, atrator turístico internacional, este povoado experimentava certo isolamento socioeconômico até a chegada da indústria do petróleo que, em função de suas potencialidades e riscos, tensionou a vida da comunidade local. Este estudo tem por objetivo analisar a vulnerabilidade socioambiental dos manguezais adjacentes à Garapuá, Cairu-BA, frente a inserção da indústria petrolífera na região, a partir da caracterização estrutural das florestas de mangue e da caracterização social do povoado de Garapuá e, particularmente, das marisqueiras usuárias deste ecossistema. As abordagens metodológicas utilizadas podem ser classificadas como pesquisas quantitativas, empregadas no levantamento fitossociológico, e qualitativas, utilizadas a partir de observações de campo e entrevistas, além de levantamentos bibliográficos, para elaboração das análises sociais. Os resultados indicam florestas de mangue de porte variável, em bom estado de conservação, com altura média das dez árvores mais altas entre 2,40,2 metros (estação 7) e 22,71,1 metros (estação 29), geralmente dominadas por Rhizophora mangle (38 das 52 estações de amostragem). A partir da caracterização estrutural foi realizado teste estatístico de agrupamento que, aliado a aspectos da arquitetura das árvores, permitiu a classificação das florestas em 12 Tipos Estruturais. As análises relativas à vulnerabilidade ambiental fundamentaram-se nos aspectos de sensibilidade e na posição fisiográfica ocupada por cada Tipo de floresta e identificaram níveis distintos de vulnerabilidade a derramamentos de óleo. Com relação aos aspectos sociais, as informações sobre os sistemas socioeconômicos e culturais relacionados à saúde, à educação, às práticas produtivas e à geração de renda, ao transporte, à religião e à organização social, como um todo, evidenciaram vulnerabilidades frente à inserção da indústria do petróleo, apontando as marisqueiras como o segmento mais suscetível a vivenciar os riscos e os impactos desse empreendimento no local. A inserção da indústria do petróleo neste contexto socioambiental representa aumento de riscos e, consequentemente, de vulnerabilidade socioambiental, na medida em que o diálogo estabelecido entre empreendedor e população se apresenta de forma assimétrica, dificultando a participação da população local, sobretudo dos mais excluídos que, nesse caso, são representados pelos usuários dos manguezais. / Mangroves are coastal marine ecosystems occurring in tropical and sub-tropical regions of the world. These environments associated with coral reefs are uncommon systems, particularly in Brazil, where Tinharé island, south coast of Bahia State, is highlighted because of the high mangrove structural development and the shellfish activities by local people. Garapuá village experienced some socioeconomic isolation, despite the proximity of Morro de São Paulo, international tourist point, until the arrival of the oil industry that, in its aspects of risks and potential, strained the village way of life. This study aims to examine the socio-environmental vulnerability of Garapuá/Bahia mangroves, facing the insertion of the oil industry in the region, by analyzing the structural characterization of mangrove forests and the social characteristics of Garapuá village, particularly, shellfish users of this ecosystem. The methodological approaches are inserted in quantitative research, used in the phytosociological studies, and qualitative, through field observations and interviews. The results indicate mangrove forests of variable size, with a height of ten biggest trees between 2.4 0.2 meters (station 7) and 22.7 1.1 meters (station 29), usually dominated by Rhizophora mangle (38 of 52 sampling stations). From the structural characterization was performed statistical analysis which, combined with aspects of the architecture of the trees, allowed the classification of forests into 12 Structural Types. Environmental vulnerability analyses were based on aspects of sensitivity and physiographic position of each Type of forest that identified different levels of vulnerability to oil spills. Regarding social aspects, the information analyzed together with field data revealed socioeconomic and cultural aspects related to health, education, income, transportation, religion, celebrations, social organization, pointing to a situation of evident social vulnerability, with the people who traditionally uses the mangrove products in the most vulnerable class. In this context, petroleum industry activities represents an increase of socio-environmental risk and, consequently, socio-environmental vulnerability, because of the dialogue asymmetry between the actors, which hindering the participation of local people, especially the most excluded, in this case focused on mangrove users.

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