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Carbonate deposits are numerous and have undeniable economic appeal for the oil industry. However, there are many uncertainties associated with different aspects of these lithologies. Understanding carbonate factories and their global distribution has been a subject of discussion in recent decades, especially concerning the products expected from different carbonate systems, their response to sea‐level variations and the transition between different depositional environments. Therefore, the goal of this study was to understand the role of sea‐level variations, and geodynamics in factories and the evolution of Albian depositional sequences on the south‐east continental margin of Brazil. Fifteen lithofacies consisting of seven facies associations and five third‐order sequences were identified. Sequence boundaries are unconformities formed by erosion or non‐deposition surfaces, representing either exposure periods or drowning events, and their correlative condensed sections. The first sequence, deposited in a shallow lagoon environment, recorded the onset of the T‐factory and the start‐up phase of the shelf. The second sequence represents a period of broad carbonate deposition in the basin, related to the catch‐up phase of the platform. The third sequence was established during a sea‐level rise and recorded the keep‐up phase of the platform and the transition from tropical to cool waters. The fourth sequence, was deposited in a deep marine environment and the fifth and last, recorded the shelf drowning. The succession typifies the beginning, the pinnacle and the end of carbonate deposition, spanning the initial and final highstand system tracts. The whole succession is part of a first‐order transgressive cycle that led to a factory transition and culminated with the definitive drowning of the depositional system.

A política externa foi um dos eixos principais do projeto político dos governos Lula. Mudanças nesta agenda proporcionaram a construção de imagem positiva do país no meio internacional, que se perpetuou durante os mandatos de sua sucessora, Dilma Rousseff. Ao mesmo tempo, esse governo aprofundou a agenda social no plano doméstico, sendo o Ministério do Desenvolvimento Social e Combate à Fome (MDS) arena institucional privilegiada no processo de formulação, implementação, avaliação e difusão de políticas sociais nos governos petistas. Este trabalho teve como objetivo construir análise transversal da articulação entre essas duas agendas de política externa e de combate à fome e à pobreza que se imbricam em processos de difusão internacional de políticas sociais brasileiras. Para tanto, a estratégia metodológica envolveu triangulação entre a literatura especializada, documentos governamentais e entrevistas semiestruturadas, de maneira a mapear elementos referentes a essa articulação, assumindo analiticamente que a circulação de determinados atores chave e suas ideias em arenas institucionais fizeram a diferença neste processo de articulação. A base teórica é oriunda da análise de políticas públicas, na forma de uma caixa de ferramentas de categorias analíticas mobilizadas para este estudo. Buscou-se elucidar, por meio de análise descritiva dos arranjos institucionais envolvidos na atuação internacional e na difusão internacional das políticas sociais do MDS, de que forma essa pasta organizava sua área internacional e quais foram as ferramentas mais importantes para sua operação. Observou-se que a produção da política externa nos oito anos de governo Lula teve influência da trajetória de seus principais formuladores e que a atuação da Agência Brasileira de Cooperação (ABC) foi essencial para o processo de difusão internacional dos programas do MDS, principalmente no contato entre demandas externas e esta pasta e no desenvolvimento de projetos de cooperação Sul-Sul. Ademais, existem indícios de que a relação entre as agendas de política externa e de combate à fome e à pobreza se deu, até certo ponto, de maneira planejada, sobretudo no plano paradigmático, ao mesmo tempo que, no plano das estratégias e articulação de instrumentos, o componente incremental parece ser mais relevante para explicar este processo Foreign policy was one of the main center lines of the Lula administration\'s political project. Changes in this agenda allowed for constructing a positive image of the country in the international environment, sustained during his successor\'s, Dilma Rousseff, terms. At the same time, this government deepened the social agenda at the domestic level, with the Ministry of Social Development and Fight against Hunger (MDS) being the privileged institutional arena in the formulation, implementation, evaluation, and diffusion processes of social policies in the PT governments. The research aimed to construct a cross-cutting analysis of the articulation between these two agendas - foreign policy and the fight against hunger and poverty - intertwined in processes of international diffusion of Brazilian social policies. To this end, the methodological strategy involved the triangulation between specialized literature, government documents, and semi-structured interviews to map elements concerning this articulation, analytically assuming that the circulation of certain key actors and their ideas in institutional arenas made a difference in this articulation process. The theoretical base comes from public policy analysis, in the form of a \"toolbox\" of analytical categories mobilized for this study. Through a descriptive analysis of the institutional arrangements involved in international action and the dissemination of MDS social policies, we sought to elucidate how this portfolio organized its international area and which were the most important tools for its operation. It was observed that the trajectory of its central formulators influenced foreign policy production during the eight years of Lula\'s administration and that the Brazilian Cooperation Agency (ABC) activities were essential to the process of international dissemination of MDS\' programs, especially for the contact between external demands and this portfolio, and the development of South-South cooperation projects. Furthermore, there are indications that the relationship between the agendas of foreign policy and the fight against hunger and poverty took place, to a certain extent, in a planned manner, especially at the paradigmatic level, while at the level of strategies and articulation of instruments, the incremental component seems to be more relevant to explain this process

La caracterización petrofísica de yacimientos desempeña un rol importante en la industria petrolera, siendo primordial en el gerenciamiento integral y la optimización de procesos de recuperación. El siguiente trabajo planteó el modelado petrofísico y de facies para las unidades formacionales del Grupo Grant y el yacimiento Anderson dentro del Bloque-Bunda-3D-2009 de la cuenca Canning en Australia. Esta propuesta fue dividida en dos etapas. La etapa conceptual se basó en el estudio de la migración y acumulación de hidrocarburos en el área, y la creación de un inventario desde la información registrada en el Sistema de Gestión de Información Geotérmica y de Petróleo de Australia Occidental (WAPIMS). La segunda etapa se desarrolló considerando que la cantidad y distribución de lutitas presentes en las areniscas, tienen un gran impacto en la productividad de los yacimientos de hidrocarburos. Así, el primer paso fue calcular el volumen de lutitas a través del índice lineal de rayos gamma. Posteriormente, se modelaron las facies mediante el uso de redes neuronales y los resultados fueron comparados con las descripciones litológicas reportadas de los núcleos de diámetro completo de perforación. La porosidad efectiva fue modelada mediante el registro de densidad volumétrica de la roca y el tipo de distribución de arcilla; la saturación de agua mediante la correlación de Poupon-Leveaux y el modelo de permeabilidad horizontal fue generado con los datos de análisis convencionales de núcleos de diámetro completo de perforación. Se resalta que la presencia de pirita afectó la respuesta de los registros de densidad volumétrica, porosidad neutrón y de resistividad para algunos pozos del área. Igualmente, el hidrodinamismo actuante y la presencia de agua meteórica en los acuíferos incidió en la respuesta del registro eléctrico resistivo, resultando complejo la identificación de contactos agua - hidrocarburo

Estudos geoquímicos e mineralógicos de arenitos e argilitos da Bacia Bauru (Cretáceo Superior), localizada na região Sudeste do Brasil foram realizados visando à determinação da proveniência, tectônica da rocha fonte, o papel de processos como intemperismo e reciclagem sedimentar na assinatura geoquímica da rocha fonte e uma evolução paleoambiental para a área de estudo. As amostras têm sua mineralogia principal composta por quartzo, microclínio, calcita, albita, dolomita e hematita. Illita, montmorillonita e paligorsquita são os argilominerais identificados. Elementos maiores, traços e terras raras e as razões elementais entre eles foram utilizadas para determinar a composição da rocha fonte. Valores do Índice Químico de Alteração e do Índice de Intemperismo Químico variando de 64 a 92 e de 84 a 98, respectivamente, e a ocorrência de feldspatos nas rochas sedimentares indicam intemperismo moderado na área fonte. Gráficos de elementos maiores e traços e valores para razões como La/Sc (1,47-4,86), (La/Yb)c (3,86-20,44) e a anomalia de Eu (Eu/Eu* = 0,62-0,92) comparados com dados da literatura sugerem que os sedimentos da Bacia Bauru na área de estudo tenham sido originados de rochas de composição quartzítica a granítico-gnáissica, derivadas de áreas continentais estáveis e depositados em ambientes de bacias intracratônica. A possível área-fonte para as rochas estudadas localiza-se a NE da Bacia Bauru, consistindo em rochas graníticas e metassedimentares do embasamento pré-cambriano. A deposição sedimentar na Bacia Bauru reflete a interação de processos aluviais e lacustres.

The Late Cretaceous Marilia Formation located in the central-southern portion of Brazil is characterized by a succession of sandstones, conglomerates, and paleosols. The paleosols constitute more than 60% of this formation, providing significant information about pedogenetic processes as well as paleoenvironmental and paleoclimate implications. The paleosols of the Marilia Formation have been studied principally from a stratigraphical, sedimentological and paleopedological point of view; however, there are no studies addressing in detail the geochemical behavior of the paleosols. Therefore, we used a robust geochemical dataset combined with stratigraphical and macromorphological interpretations as well as clay mineralogy to conduct a paleoenvironmental and paleoclimate analysis of the Marilia Formation in the western portion of the state of Minas Gerais in Brazil. The results indicate that the paleosols of the Marilia Formation can be divided into three pedotypes and pedochemical units based on their geochemical variations and are limited at the base and top by pedochemical markers. Moreover, X-ray diffraction identified quartz and calcite as primary minerals associated with montmorillonite, smectite, illite and palygorskite, indicating wet periods combined with dry stages associated principally with dry and arid environments. The paleosol distribution and weathering index allow us to interpret the paleoenvironmental evolution of the Late Cretaceous Marilia Formation, suggesting an increase in humidity from east to west in the study area.

A geoquimica dos elementos maiores e traco tem sido usada como importante ferramenta para o estudo da proveniencia, evolucao tectonica e climatica das bacias sedimentares. A Formacao de Sao Carlos e uma unidade do Cretaceo Superior que ocorre na borda leste da Bacia Bauru. Apesar dos estudos paleontologicos e paleodeposicionais realizados nesta unidade nos ultimos anos, pouco se sabe sobre as condicoes tectonicas e climaticas que atuam nos primeiros estagios da sedimentacao, bem como, sua relacao estratigrafica com outras unidades da bacia. A hipotese deste trabalho consiste em avaliar se as formacoes Sao Carlos e Aracatuba possuem correspondencia e compreender a evolucao da margem leste da bacia. Dessa forma, realizaram-se estudos geoquimicos utilizando Fluorescencia de Raios-X em arenitos, siltitos e folhelhos da Formacao Sao Carlos. Atraves do uso do indice de intemperismo quimico, os oxidos dos elementos maiores indicam que, com valores entre 57,12 e 71,58%, os processos de intemperismo moderados, possivelmente associados ao clima arido-semiarido, afetaram a area de origem. Rochas alcalinas, granitos, gnaisses e metassedimentos foram os principais litotipos da area fonte. Os diagramas ternarios indicam que o ambiente tectonico era equivalente a margem continental passiva, coincidindo com as regioes da Serra do Mar e, em segundo lugar, Soerguimento Alto Paranaiba. Com base nos elementos maiores e tracos, suas razoes, e dados ja publicados da bacia, foi elaborado um modelo paleogeografico da borda leste da Bacia Bauru, concluindo-se que a area de origem dos sedimentos foi constituida por rochas intermediarias e felsicas, as vezes recicladas por processos sedimentares.

The Eastern Marlim oilfield, located in the northeastern offshore of the Campos Basin, is a portion of the Marlim Complex, one of the most important oil accumulations ever found in Brazil. This paper presents findings from lithofacies, sequence stratigraphy and petrophysical analyses for the Oligocene-Miocene section of the Eastern Marlim oilfield. Here, we evaluate at least four main lithofacies associations and three major zones recognized in the latter section, presenting sedimentological and stratigraphical interpretations based on stratigraphic correlations, distribution and sand proportion maps, and accompanying petrophysical analysis. Our findings suggest at least two bipartite turbiditic flows representing different stages of deposition associated with a deep-water turbidite sequence, composing the elements of a submarine lobe complex. Massive unconsolidated amalgamated sandstone bodies, displaying very good porosity, lateral and vertical continuity, reflecting excellent reservoirs. The final depositional model of the studied Oligocene-Miocene interval in this work is part of the first-order Highstand System Tract (HST) of the Campos Basin, which in turn represents a second-order, exploration-scale depositional sequence. Finally, the sequence stratigraphic model of the Oligocene-Miocene section of the Eastern Marlim oilfield has an architecture similar to those that have been developed from Oligocene-Miocene global sea level changes.

Rhizoliths are organosedimentary structures produced by plants and are an important proxy for paleoenvironmental reconstructions because the differences in the morphology of rhizoliths and their rooting depths can be used to interpret soil humidity regimes, overall biomass at the soil surface, and the behavior of the water table. With the objective of advancing knowledge on rhizoliths, a study was performed on the macromorphological and micromorphological characterizations of the rhizoliths preserved in the thirty-one paleosols of the Marilia Formation in Minas Gerais, southeastern Brazil. Based on the topological and architectural attributes of rhizoliths, and on their possible functional adaptations, such as mycorrhizal associations, three different types of rhizoliths are described in this study and represent at least three different plants: rhizohaloes, root casts and rhizocretions. Well-developed paleosols with nodular horizons contain the higher density of long root casts, indicating a seasonally dry environment, because the root casts present two meters in length. These adaptations are associated with an exploitation of a lowered water table during most times of the year. The higher density of rhizoliths indicates an area with agglomerated arboreous arbustive vegetation cover. Paleosols with chalky horizons also show a high density of root casts, indicating a landscape with high plant density that is adapted to drained soils, but with a seasonally elevated water table or the influence of ephemeral flows, given the proximity to the flow channels. The poorly drained paleosols with redoximorphic features show the lowest density of rhizoliths, thus indicating an incipient vegetation in response to near-surface water table and waterlogged soils in a distal floodplain. The rhizogenic laminar horizons have developed near fluvial channels with frequent sedimentary input, resulting in a sequence of laminar horizons composed of rhizocretions that are separated by sandy deposits or poorly developed pedogenic horizons. The micromorphological analysis on the rhizogenic laminar calcretes showed biogenic features, such as alveolar septal structures, calcified filaments, microcodium, calcified cells and pisoliths. Despite the scarce paleobotanical findings in the Marilia Formation, the results obtained indicate an ecosystem that was composed of plants varying from herbaceous to arboreous, with an environment similar to modern semiarid shrublands.

The current research was performed in the eastern portion of the Marlim oilfield to identify the hydrocarbon-generating potential of the Albian-Oligocene sequences (Macae Group, Ubatuba and Carapebus formations) in the Campos Basin, Brazil. On the basis of petroleum geochemical proxies, an integrated approach was developed using source rock characterizations to establish the distribution of source rock properties, such as organic matter content, hydrocarbon-generating potential, thermal maturity and stratigraphic thickness. The outcomes of a comprehensive petroleum geochemical characterization were integrated with cuttings and core sample descriptions, biostratigraphic controls, well log analyses and 2-D/3-D seismic interpretations. Our results reveal that for the Albian-Oligocene deposits, the key geochemical properties required to develop hydrocarbon source kitchens converge in specific locations, demonstrating a variable hydrocarbon potential ranging from poor to excellent and suggesting the existence of local generation pods in the central and principally northern portions of the research area. The accumulation and preservation of the organic matter were influenced by the paleo-topography and tectonic controls, and the lowest concentrations of organic carbon were attributed to significant siliciclastic dilution taking place mostly toward the middle and southern portions of the Eastern Marlim oilfield. Lateral variations in both the lithofacies and organic facies are the main conditions controlling the behavior of the petroleum potential in the investigated sediments. Our results indicate that the Macae Group has sufficient source-rock potential, maturation patterns, and hydrocarbon-generating potential to be considered as an active source rock in the Eastern Marlim oilfield, where the petroleum geochemical properties converge and are adequate to generate hydrocarbon compounds. In addition, the Ubatuba and Carapebus formations are also likely to generate oil and/or gas, but due to their relatively low maturity, it is difficult to establish that these rocks can be active source rocks in the study area.

Made available in DSpace on 2021-06-25T11:23:24Z (GMT). No. of bitstreams: 0 Previous issue date: 2020-09-01 The petrophysical characterization of deposits plays an important role in the oil industry, primarily in the integral management and optimization of recovery processes. The following project presents the petrophysical and facies modeling for the formational units of the Grant Group and the Anderson deposit within the Block-Bunda-3D-2009 of the Canning Basin in Australia. This proposal was divided into two stages. The conceptual stage was based on the study of hydrocarbon migration and accumulation in the area, and the creation of an inventory from the information recorded in the Western Australia Geothermal and Petroleum Information Management System (WAPIMS). The second stage was developed considering that the quantity and distribution of shales present in the sandstone, have a great impact on the productivity of hydrocarbon reservoirs. Thus, the first step was to calculate the volume of shales through the linear index of gamma rays. Subsequently, the facies were modeled using neural networks and the results were compared with the lithological descriptions reported of the full diameter drilling cores. The effective porosity was modeled by recording the volumetric density of the rock and the type of distribution of clay; water saturation by Poupon-Leveaux correlation and the horizontal permeability model was generated with conventional core drilling analysis data. It is highlighted that the presence of pyrite, affected the response of volumetric density, neutron porosity and resistivity records for some wells in the area. Likewise, the acting hydrodynamism and the presence of meteoric water in the aquifers affected the response of the resistive electrical record, making the identification of water-oil contacts complex. Univ Ind Santander, Bucaramanga, Colombia Univ Estadual Campinas, Campinas, Brazil Ecopetrol, Bogota, Colombia Univ Estadual Paulista, Sao Paulo, Brazil Univ Estadual Paulista, Sao Paulo, Brazil

O Grupo Itarare compreende pacotes sedimentares sindeposicionais de diferentes ambientes deposicionais. Sua genese e relacionada a ambientes fluvio-lacustre e marinho sob influencia da acao de geleiras. O presente trabalho visou interpretar os elementos arquitetonicos do afloramento na regiao de Salto (SP) e propos um modelo deposional em escala regional para o ambiente. O afloramento apresenta uma sucessao de turbiditos com granulometria variando de muito fino a grosso e a principal estrutura sedimentar verificada sao estratificacoes cruzadas de baixo ângulo. O fluxo das paleocorrentes tem direcao geral predominantemente NW. A analise dos eventos paleoclimaticos, geometria, estruturas sedimentares e facies, alem da direcao das paleocorrentes permitiu a verificacao que o ambiente deposicional insere-se em um contexto de cunha de mar baixo.

Esta Iniciacao Cientifica tem como finalidade uma analise petrofisica das camadas heteroliticas das formacoes Presidente Prudente e Santo Anastacio, pertencentes a Bacia Bauru. A permeabilidade e a porosidade das rochas dessas unidades serao obtidas atraves da analise de lâminas petrograficas, softwares e calculos associados que possibilitam inferir a variacao vertical destes parâmetros petrofisicos num modelo analogo de reservatorio.

This is the first report of trace fossils potentially associated with insect social behavior in sandy and well-drained paleosols of the Upper Cretaceous continental sequence of Brazil. The trace fossils consist of dozens of lobed and vertical structures cemented by CaCO 3 and preserved mainly in full relief in paleosols of the Marilia Formation (Bauru Basin) in the state of Minas Gerais. The described ichnofossils are predominantly vertical, up to 2 m long, and are composed of horizontal lobed structures connected by vertical tunnel-like structures that intersect in the center and at the edges. The lobed structures range from 3 to 15 cm long and 2–6 cm thick. Two different hypotheses are analyzed to explain the origin of the trace fossils; the less probable one is that the structures are laminar calcretes associated with rhizoliths and rhizoconcretions. The hypothesis involving social insects was considered because the trace fossils described herein partially resemble a modern ant nest and the ichnofossil Daimoniobarax. The micromorphological analysis of the lobed and tunnel-like structures indicates modifications of the walls, such as the presence of inorganic fluidized linings, dark linings and oriented grains, supporting the hypothesis that they are chambers and shafts. The architecture and size of the reported nests suggest the possibility that social insect colonies existed during the Maastrichtian and are direct evidence of the social behavior and reproductive strategies of the Cretaceous pedofauna.

An organic geochemical investigation combined with sequence stratigraphy was performed in the Ceara Basin, an offshore basin located in Northeastern Brazil. The information available from 30 well logs (gamma-ray, resistivity, density), besides geochemical (TOC, and pyrolysis indexes) and isotopic (δ13C) data, aided the preparation of a dataset for this study. The application of sequence-stratigraphic methods helped classify and correlate seismic and organic facies. Four key petroleum source-rock units were identified, from the oldest to the youngest: (1) Mundau Formation – top of the Rift Sequence (Berriasian-Aptian); (2) Paracuru Formation – Breakup Sequence (Aptian-Albian); (3) Itapaje Member of the Ubarana Formation – Continental Drift Sequence (Albian-Turonian), and (4) Uruburetama Member of the Ubarana Formation – Continental Drift Sequence (Turonian-Maastrichtian). The geochemical characteristics of the Mundau Formation (high total organic carbon (TOC), hydrogen index (HI), relative hydrocarbon potential (RHP = (S1 + S2)/TOC)) point to a typical transgressive sequence. Six transgressive-regressive (T-R) cycles were recognized in the entire Paracuru Formation. The best geochemical marker is related to the top of the Paracuru Formation. This stratigraphic unit can be correlated to a major anoxic event and is the best source rock of this basin. Evaporitic facies found in this top section, maximum RHP values (anoxic conditions), and maximum flooding surfaces related to transgressive events characterize this interval. Moreover, the wide spatial cover of organic-rich rocks, carbon isotopic data, and the recognition of favorable characteristics for anoxia in other basins of the Equatorial Margin are suggestive of the Aptian-Albian Oceanic Anoxic Event (OAE-1b) occurring in the Ceara Basin. The Ubarana Formation represented by the Uruburetama Member and the Itapaje Member yields the least promising source rocks. However, high TOC values suggest the occurrence of the late Cenomanian–early Turonian Oceanic Anoxic Event (OAE-2), when organic-rich strata started to deposit in deep-water regions. The predominance of a regressive interval in the Uruburetama Member points to oxic or sub-oxic conditions. Additionally, the correlations between the Brazilian Equatorial Margin and its African counterpart, and the organic geochemical characterization allied to the definition of depositional systems for these regions proved to be useful for oil exploration.