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Governments, the community and industry expect public policy to be implemented effectively and efficiently, particularly when that policy and regulation affects the economic well being and environmental values of the nation. The offshore petroleum exploration and production industry is a case where public policy and regulation are attracting national focus through discussions on the timing of world peak oil production and the future of national and global oil and gas production. An overseas history of famous environmental disasters associated with petroleum exploration and production and transportation also ensures a specific focus on the environmental regulation of the industry. This study elaborates the history and characteristics of the offshore petroleum E&Pindustries in Australia and the US, and the systems and processes used to provide technical advice that informs and advises the regulation of those industries. The study then analyses the management of technical advice for government regulation of the offshore petroleum exploration and production (E&P) industry in Australia using the US equivalent as benchmark. Further, the analysis develops a model that incorporates strategic and operational elements of such advice. Strategic elements include openness, transparency and accountability, and operational elements include use of expertise, timeliness and peer communication. The study illustrates the relative challenges to providing technical advice under Australia�s Westminister form of government which can be less open, transparent and accountable when compared to the US Congressional form of government. The study also shows the greater use of expertise and peer communication associated with the more extensive petroleum research effort in the US, reflecting the greater age and size of its petroleum industry.

Orientador: Carlos Roberto de Souza Filho / Tese (doutorado) - Universidade Estadual de Campinas, Instituto de Geociências / Made available in DSpace on 2018-08-26T21:42:34Z (GMT). No. of bitstreams: 1 Magalhaes_LuciolaAlves_D.pdf: 18006745 bytes, checksum: e07ddabc39328486a6c0a93b03caf806 (MD5) Previous issue date: 2015 / Resumo: Os reservatórios de petróleo são insuficientemente selados, permitindo escapes de fluidos que atingem a superfície e formam exsudações. As exsudações de hidrocarbonetos (HCs) gasosos são, muitas vezes, visualmente imperceptíveis. Porém, alteram o pH e o Eh do meio, favorecem a transformação de fases minerais (causando anomalias mineralógicas e geofísicas) e induzem estresse na vegetação. Dados e técnicas de processamento espectral são úteis para mapear tais alterações e auxiliar na descoberta de novas acumulações de petróleo. O objetivo desta pesquisa foi investigar alterações dessa natureza nas bacias continentais brasileiras, considerando cenários desenvolvidos sob diferentes regimes climáticos e contextos geológicos distintos. As regiões do Diápiro do Cinzento/BA e do Remanso do Fogo/MG, onde são registradas exsudações naturais de óleo e gás, respectivamente, foram selecionadas como estudos de caso. Essas áreas estão situadas nas bacias sedimentares do Recôncavo/BA e do São Francisco/MG. A Bacia do Recôncavo é a segunda bacia terrestre brasileira em volume de produção de petróleo. Apesar de seu elevado número de campos em produção, ainda conta com diversos trabalhos exploratórios para a descoberta de novos plays. A Bacia do São Francisco, por sua vez, encontra-se em fase de exploração e diversos poços recentemente perfurados mostraram indícios da existência de gás. Dados de gasometria de solos, dados radiométricos aéreos e terrestres, dados de espectroscopia de refletância de solos, rochas e vegetação, dados de difração de raios-X e imagens multiespectrais dos sensores ASTER e RapidEye e hiperespectrais do sensor ProSpecTIR-VS foram utilizados para mapear essas exsudações. Como resultado da análise da composição mineralógica dos solos do Remanso do Fogo, foi possível identificar as microexsudações com base na variação da profundidade das bandas de absorção da caulinita e dos óxidos/hidróxidos de ferro. Anomalias na vegetação foram mapeadas a partir das imagens ASTER e ProSpecTIR-VS. Os dados radiométricos terrestres indicam perda de potássio e enriquecimento em urânio nas áreas próximas às microexsudações. No Diápiro do Cinzento, a degradação do HC gerou um ambiente ácido e rico em sulfato, proporcionando a formação da assembléia jarosita-pirita-goetita - minerais identificados a partir de dados de espectroscopia de reflectância e de difração de raios-X. Nas porções mais distais da zona de exsudação, a hematita e a goetita são as fases mais estáveis. As imagens multiespectrais do RapidEye foram eficazes no mapeamento dos minerais relacionados à esses ambientes com pH distintos no Diápiro. Dentre as principais contribuições desta pesquisa, destaca-se o avanço no conhecimento das alterações mineralógicas induzidas pelas exsudações de HCs líquidos e gasosos em bacias sedimentares brasileiras submetidas a diferentes regimes tectônicos, condicionantes das exsudações. Adicionalmente, demonstrou-se a importância da utilização de dados adquiridos sob diferentes resoluções espaciais e espectrais no mapeamento do fenômeno que, conforme ficou demonstrado, ocorre de forma restrita, enquanto seeps individuais. O conjunto dos resultados da pesquisa revelou novos parâmetros exploratórios que podem ser testados e utilizados para a prospecção petrolífera em território nacional / Abstract: Petroleum reservoirs are not entirely sealed, thus allowing leaks of lighter hydrocarbons (HC) to reach the surface and form microseepages. Gas microseeps are usually undetectable by the naked eye. However, the HC biodegradation changes the pH and Eh of the environment, induces alterations in geological materials (resulting in mineralogical and geophysical anomalies) and causes stress in vegetation. Remote sensing and radiometric data are potentially useful to identify these alterations and to discover new petroleum plays. The goal of this research was to investigate the mineralogical changes induced by oil and gas seeps in Brazilian sedimentary basins under different climatic conditions and geological settings. The Diápiro do Cinzento (Bahia (BA) State) and Remanso do Fogo (Minas Gerais (MG) State) are considered archetype areas in Brazil for oil and gas seeps research, respectively. These areas are located in the Recôncavo (BA) and São Francisco (MG) sedimentary basins. The Recôncavo basin hosts the second largest oil producing fields among onshore basins in Brazil. Despite the large number of productive brownfields, the basin is still the focus of exploration activities. In contrast, the São Francisco Basin is yet in the exploration stage. Several wells recently drilled in greenfields in the basin showed evidences of gas. Gasometric data, airborne and terrestrial radiometric data, reflectance spectroscopy data of soils, rocks and vegetation, X-ray diffraction data, ASTER and RapidEye multispectral imagery and ProspecTIR-VS hyperspectral imagery were employed in the research. Continuum-removed VNIR and SWIR spectra of soils in the Remanso do Fogo area were used to vectorize the location of microseeps based on the absorption bands of kaolinite and iron oxides/hydroxides. Vegetation stress was mapped using both ASTER multispectral and ProSpecTIR-VS hyperspectral data. Ground gammaspectrometric data collected around proven microseeps show loss of potassium and enrichment of uranium, as verified in several sites. In the Diápiro do Cinzento, the mineralogical assemblage of jarosite-pyrite-goethite is intrinsically related to hydrocarbon degradation. Such minerals, which indicate acidic and sulfate-rich conditions, were promptly detected by reflectance spectroscopy and X-ray diffraction. Far from the macroseepage zone, iron minerals such as hematite and goethite predominate. RapidEye multispectral images were effective for mapping these minerals remotely in the Diápiro do Cinzento, reflecting environments with different pH conditions. The main contribution of this research was to improve the knowledge of mineralogical changes induced by oil and gas hydrocarbon seeps in Brazilian sedimentary basins formed under different tectonic settings. Additionally, this research demonstrated the usefulness of remote sensing data yielded at various spectral and spatial resolutions to map the seepage phenomena. Evidences at multiple scales show that individual seeps can be more spatially restricted that previously envisaged and display specific mineralogical and geobotanic features in a small area. The overall results of the research offer new perspectives for petroleum exploration in Brazilian offshore basins / Doutorado / Geologia e Recursos Naturais / Doutora em Ciências

>Magister Scientiae - MSc / Durban Basin located on the eastern coast of South Africa has been a focus of interest for Petroleum Exploration for the last few decades. Only four exploratory wells have been drilled in this offshore basin without success. During the initial stage of its creation, the basin suffered major tectonic disturbance as evident from the presence extensional faults followed by intense igneous activities. This was followed by marine sedimentation in the late Mesozoic (late Jurassic-early Cretaceous). An attempt has been made in this work to understand the distribution of the rock in space and time for the early Cretaceous sediments considered most prospective for hydrocarbon exploration in Southern Africa. Temporal distribution of planktonic foraminifera helps in identification of the three early Cretaceous (Barremian to Albian) stages within the drilled intervals. Foraminiferal biostratigraphic studies integrated with sedimentology, log motif analysis and seismic data analysis helps to predict paleodepth and depositional environment during early Cretaceous in this research. The integrated analysis reveals that during the Barremian-early Aptian stages graben filled sediments were deposited in a marine shelf in the northern part of the studied area (site Jc-D1) whereas, in the central and southern part finer clastics were deposited in middle slope (site Jc-B1 and Jc-C1). The thick claystone section and presence of minor limestone lenses and their benthic foraminifera assemblage in late Aptian-Albian stage in the northern area indicates possibility of submarine fan. Overlying succession dated between late Aptian to Albian and early part of Cenomanian interval in the three studied exploratory wells shows serrated log signatures. The dominant claystone lithology with intermittent siltstone/sandstone units and the benthic foraminifera indicates fluctuating distal marine slope environment with periodic shallowness in the entire area.

[pt] Com o crescente aumento de lâminas d`água na área de exploração e produção de petróleo no mar, surgiu também o aumento de unidades de exploração e produção tipo semi - submersíveis. Os risers rígidos em catenária surgiram então como solução para exportar óleo e gás das plataformas semi- submersíveis até os dutos de transporte. Do ponto de vista de fadiga, existem duas regiões críticas onde ocorrem as maiores tensões, em um projeto de riser: o trecho junto ao ponto de conexão na plataforma e o trecho junto ao piso marinho (TDP). Os risers rígidos em catenária, SCRs ou steel catenary risers, constituem-se hoje em uma das principais soluções para águas profundas e ultra-profundas. Sua principal aplicabilidade baseia-se no fato de ser a única solução viável em lâminas d`água acima de 1500m, onde as linhas flexíveis ainda não podem ser utilizadas, em função da elevada pressão externa. Este trabalho apresenta um estudo da interação solo-duto de risers rígidos é constituído de duas partes: na primeira são relatados os resultados de um modelo físico realizado no IPT (Instituto de Pesquisas Tecnológicas), e, na segunda os resultados de análises numéricas que procuraram reproduzir os ensaios no modelo físico. São apresentadas também comparações entre os dois modelos. Os resultados permitiram estabelecer um modelo constitutivo simplificado do comportamento do contato solo-duto em condições de carregamento lateral. / [en] The necessity for offshore oil exploration to reach greater depths, pushed the demands for semi-submersible exploration and production units. Presently, steel catenary risers (SCR) appear to be the best recommended technical solution for oil and gas exploration.Concerning to the fatigue analysis there are two critical stress points to be considered: close to the platform connection and a second one at the touch down point - TDP. SCR is currently one of the main solutions for deep and ultra deep water projects. It is the only technical solution available for water depths beyond 1500m where flexible lines cannot yet be used due to excessive external pressure.The present work presents a study on the interaction between SCRs and soil. It is divided in two parts. The first describes an experiment (physical model) which was carried out at the laboratories of IPT (Instituto de Pesquisas Tecnológicas) in São Paulo. The second part presents a numerical, finite element analysis of the soil-SCR interaction. The comparison between experimental and numerical results allowed the determination of a simplified constitutive model for the representation of soil-pipe contact under horizontal loads.

[pt] Estudos econômicos de áreas com indícios de hidrocarbonetos estão imersos em incertezas de diferentes naturezas (geológicas, de engenharia e econômicas). No início do estudo, aspectos da geologia, dos fluidos, das rochas e do reservatório só são conhecidos por métodos indiretos que fornecem informações imprecisas. A redução dessas incertezas é limitada pelos elevados custos de perfuração de poços que permitam testes diretos. Conseqüentemente, decisões de investimentos de exploração têm que ser tomadas sob risco motivando, assim, o desenvolvimento de métodos para a avaliação econômica probabilística de propriedades. O foco desta dissertação é a avaliação econômica probabilística de recursos petrolíferos, antes da perfuração do poço pioneiro. O cálculo do valor econômico de uma propriedade depende das estimativas dos perfis temporais de receitas e custos associados ao seu desenvolvimento e produção (D e P). A obtenção de tais elementos requer um projeto de D e P para a propriedade que, em função dos dados disponíveis, é menos detalhado do que um projeto de simulação multicelular. Nesta dissertação, uma metodologia de avaliação baseada em simulação de Monte Carlo é apresentada juntamente com uma implementação- protótipo. A realização das numerosas replicações, necessárias para se obter uma avaliação probabilística, se torna viável graças a um programa capaz de gerar o projeto de D e P automaticamente. Esse programa foi desenvolvido pela Petrobras com base em regras fornecidas por um especialista. Além da justificativa para a abordagem adotada, da descrição e implementação do método, são feitas considerações sobre distribuições de probabilidade para codificar incertezas e sobre os resultados dos testes iniciais do sistema protótipo. / [en] Economics studies of areas with indications of hydrocarbons are submerged in uncertainties of assorted natures (geological, of engineering and economical). At the start of the study, aspects concerning the geology, the fluids, the rocks and the reservoir are only known through indirect methods that yield imprecise information. The reduction of these uncertainties is limited by high costs of drilling wells that allow direct tests. Consequently, decisions on exploration investments have to be made under risk. This motivates the development of methods for probabilistic economic evaluation of properties. This dissertation addresses the probabilistic economic evaluation of petroleum resources, prior wildcat well drilling. Assessing the economic value of a property depends on estimates of incomes and costs time profiles associated to its development and production (D and P). Obtaining such elements requires a D and P project for the property that, due to the limited data available, is less detailed than a multi- cellular simulation project. In this thesis, a probabilistic evaluation methodology based on Monte Carlo simulation is presented along with a prototype implementation. Performing the numerous replications necessary to obtain a probabilistic evaluation becomes feasible thanks to a procedure capable of automatically generating the D and P project. That procedure was developed by Petrobras based on heuristic rules supplied by an expert. In addition to a justification for the proposed approach, the description of the method and its implementation, comments are made on probability density functions used for encoding uncertainties, and on the results of the initial tests with the prototype system.

The aim of this thesis is to develop a methodology for detection of naturally occurring offshore oil slicks originating from hydrocarbon seeps using satellite remote sensing techniques. In this scope, Synthetic Aperture Radar (SAR) imagery has been utilized. Case study area was Andrusov High in the Central Black Sea. Hydrocarbon seepage from tectonic or stratigraphic origin at the sea floor causes oily gas plumes to rise up to the sea surface. They form thin oil films on the sea surface called oil slicks. Presence of seeps and surface oil slicks for the offshore basins is a trace of depleted oil traps. Spatial distribution of oil slicks is closely related to sea waves, dominant wind patterns and weathering factors. Even though, there are oil slick detection techniques available with optical remote sensing, laser fluorosensors, and hyperspectral remote sensing, the most efficient results can be obtained from active microwave sensors like synthetic aperture radar (SAR). SAR sensors simply measure the backscattered radiation from the surface and show the roughness of the terrain. Oil slicks dampen the sea waves creating dark patches in the SAR image. In this context an adapted methodology has been proposed, including three levels namely / visual inspection, image filtering and object based fuzzy classification. With visual inspection, targets have been identified and subset scenes have been created. Subset scenes have been categorized into 3 cases based on contrast difference of dark spots to the surroundings. Then object based classification has been utilized with the fuzzy membership functions defined by extracted features of layer values, shape and texture from segmented and filtered SAR subsets. As a result, oil slicks have been discriminated from look-alikes which are the phenomena resembling oil slicks. The overall classification accuracy obtained by averaging three different cases is 83 % for oil slicks and 77 % for look-alikes. The results of this study can considered to be a preliminary work and supplementary information for determining the best operational procedure of offshore hydrocarbon exploration.

Magister Legum - LLM / South Africa