398 resultados para Conglomerados
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De acordo com dados de 07.10.2014 da Associação Brasileira das Entidades dos Mercados Financeiro e de Capitais – ANBIMA, no acumulado em 12 meses, entre aplicações, resgates e captações, a indústria de fundos movimentou mais de 11 bilhões de reais no Brasil. É um volume financeiro considerável, fazendo dos fundos de investimento importantes instrumentos de captação de poupança e de direcionamento de recursos para os mais diversos projetos de financiamento da economia. Além disso, as quebras de determinados conglomerados financeiros no Brasil nos últimos anos envolvendo fundos administrados e geridos por sociedades pertencentes a esses conglomerados colocou em evidência a importância de regras e estudos direcionados à relação entre o administrador-gestor e o cotista de fundos de investimento. De fato, pesquisa conduzida ao longo dos anos de 2013 e 2014 demonstrou que acadêmicos, reguladores e demais participantes do mercado de valores mobiliários possuem poucos estudos que possam assisti-los na solução de problemas relativos a essa relação, inclusive diante de situações envolvendo conflitos de interesses entre administradores-gestores e cotistas. Assim, diante da importância econômica dos fundos de investimento para o Brasil, da relevância dos direitos dos investidores dentro da indústria de fundos, e também em razão da escassez de estudos, este trabalho tem por finalidade realizar investigação teórica e empírica sobre a relação fiduciária entre o administrador, o gestor e os respectivos cotistas dos fundos de investimento. Dessa forma, o objetivo será identificar a origem, as características essenciais dessa relação, os riscos que ela pode trazer para o investidor e os deveres que ela impõe aos administradores e gestores. Para tanto, propõe-se avaliar a origem histórica da relação fiduciária e os fundamentos teóricos que a suportam aplicados aos fundos de investimento nos Estados Unidos e no Brasil. Com base nesse conhecimento teórico e sob o enfoque dos deveres fiduciários aplicáveis aos administradores e gestores, parte-se para a avaliação das normas de conduta contidas nas instruções da Comissão de Valores Mobiliários (CVM), visando testar as características da relação fiduciária diante das regras da CVM. Por fim, realiza-se estudo sobre casos em que administradores e gestores foram condenados por quebra na relação fiduciária e por inobservância de deveres específicos embutidos nas normas de conduta avaliadas anteriormente. Com fundamento nos estudos teóricos e empíricos descritos, conclui-se que existem características essenciais na configuração de uma relação fiduciária entre o administrador-gestor e o cotista de fundos de investimento e que, uma vez formada essa relação, administradores e gestores obrigam-se a observar o cumprimento de deveres de diligência e de lealdade perante o cotista. Igualmente, ainda é possível afirmar que as normas da CVM de fato instituem a relação fiduciária entre o administrador-gestor e o cotista de fundos de investimento, bem como os deveres fiduciários conexos a essa relação.
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Este artigo apresenta modelos de parcerias que podem ser celebrados pela prefeitura de São Paulo com a finalidade de estruturar um cluster de moda na região da luz, centro do município. A escolha do setor têxtil para a proposta se baseou na importância que esta indústria tem na cidade de São Paulo e no seu potencial de crescimento, tendo em vista a baixa qualificação e inovação apontada pelos dados do setor. A delimitação da região da luz considerou a vocação da região já ocupada pelo comércio de moda e por ser uma região estratégica para o município. Com esse artigo objetiva-se projetar a cidade de São Paulo como grande produtor de moda no mundo e recuperar a região da luz por meio de parcerias com parceiros privados, ou seja, com ações com baixo impacto no orçamento municipal.
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O estudo de aglomerações produtivas aponta o Estado como protagonista no apoio à cooperação interinstitucional em função do aumento da competitividade de empresas dos mais diversos setores, favorecendo o desenvolvimento regional por meio de políticas públicas. Esta pesquisa objetivou analisar o desenho dos Arranjos Produtivos Locais (APLs) no estado do Espírito Santo (ES) como instrumentos de política pública para o desenvolvimento local, segundo a percepção de atores estratégicos sobre processos decisórios presentes na implementação da Política Nacional de Apoio a APLs, a partir da análise dos APLs de Agroturismo, Metalmecânico e de Rochas Ornamentais. O caso do Cluster Quesero de Villa María complementa as análises, evidenciando semelhanças e diferenças entre aglomerações produtivas apoiadas por políticas públicas no Brasil e na Argentina. O estudo utilizou como base teórica o processo decisório e grupos de veto em políticas públicas, a abordagem incremental e de governança multinível, e o referencial sobre APLs. A pesquisa, de natureza qualitativa, utilizou entrevistas para captar as percepções de atores relevantes à implementação das políticas no ES e em Villa María acerca dos processos decisórios, seus membros e relações; fontes de dados bibliográficos e documentais também foram utilizadas, e as informações passaram por Análise de Conteúdo. Os resultados indicam características incrementais em toda a cadeia decisória, formada por vários processos de decisão diferentes. Foram identificados poucos efeitos da Política Nacional em sua implementação no ES, além de uma decadência do uso da abordagem de APLs no estado. As aglomerações produtivas foram organizadas mediante iniciativas top-down; mas duas desenvolveram características bottom-up, dada a apropriação de seus membros quanto às propostas em desenvolvimento. As aglomerações foram analisadas conforme características como: Atuação da Governança; Heterogeneidade do Grupo Decisor; Fluxo de Organização do APL; Relação com Governos; Existência de Canais de Participação de Grupos de Trabalhadores e da Comunidade Local. São identificadas relações assimétricas entre os atores em processos decisórios, nos casos brasileiros e no argentino, derivadas de assimetrias quanto a informações, acesso à participação e poder decisório por parte de grupos relacionados ao seu desenvolvimento. Grupos empresariais, governamentais e de instituições de apoio são protagonistas nesses processos decisórios, enquanto representações sociais e trabalhistas, mesmo relevantes aos APLs, não participam dos mesmos. A inclusão de diferentes atores com interesses diversos nos processos decisórios, por um lado, pode gerar conflitos e morosidade decisória; em contrapartida, tende a gerar decisões, mudanças e ações mais integradas às realidades locais, segundo variados pontos de vista, e, portanto, mais efetivas e inteligentes. Além disso, o desenvolvimento local, mediante incentivo a APLs, poderá ser alcançado na medida em que esses atores sejam incluídos nas tomadas de decisão, pois o consideraria sob sua perspectiva de associação entre dinamismo econômico e melhoria da qualidade de vida da população, tendo em vista sua sustentabilidade.
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Esta tese apresenta algumas abordagens ainda não exploradas na avaliação e construção de rankings, exclusivamente daqueles baseados em indicadores compostos. Para isso, três artigos foram desenvolvidos com o intuito de evoluir com uma literatura genericamente aplicável, ou seja, não restrita a contextos de rankings específicos. No primeiro desses artigos, composto por três estudos, mostrou-se que as informações percebidas pelos usuários através dos rankings nem sempre são fornecidas por eles. No segundo, o qual pode ser entendido como uma extensão do primeiro, propôs-se a criação de uma métrica – intitulada COMP – destinada a mensurar o grau de compatibilidade entre as informações percebidas pelos usuários e aquelas fornecidas pelos rankings. No terceiro artigo, independente dos dois primeiros, explorou-se o potencial da Teoria de Resposta ao Item (TRI) enquanto metodologia para a avaliação e construção de rankings. Para isso, dois estudos, o primeiro deles focado no Failed States Index (FSI) e o segundo no Index of Economic Freedom (IEF) foram desenvolvidos para mostrar as potencialidades da metodologia proposta.
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Unidade 4
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Last century Six Sigma Strategy has been the focus of study for many scientists, between the discoveries we have the importance of data process for the free of error product manufactory. So, this work focuses on data quality importance in an enterprise. For this, a descriptive-exploratory study of seventeen pharmacies of manipulations from Rio Grande do Norte was undertaken with the objective to be able to create a base structure model to classify enterprises according to their data bases. Therefore, statistical methods such as cluster and discriminant analyses were used applied to a questionnaire built for this specific study. Data collection identified four group showing strong and weak characteristics for each group and that are differentiated from each other
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Information is one of the most valuable organization s assets, mainly on a global and highly competitive world. On this scenery there are two antagonists forces: on one side, organizations struggle for keeping protected its information, specially those considered as strategic, on the other side, the invaders, leaded by innumerous reasons - such as hobby, challenge or one single protest with the intention of capturing and corrupting the information of other organizations. This thesis presents the descriptive results of one research that had as its main objective to identify which variables influence the Executives´ and CIOs´ perceptions toward Information Security. In addition, the research also identified the profile of Rio Grande do Norte s organizations and its Executives/CIOs concerning Information Security, computed the level of agreement of the respondents according to NBR ISO/IEC 17799 (Information technology Code of practice for information security management) on its dimension Access Control. The research was based on a model, which took into account the following variables: origin of the organization s capital, sector of production, number of PCs networked, number of employees with rights to network, number of attacks suffered by the organizations, respondent´s positions, education level, literacy on Information Technology and specific training on network. In the goal´s point of view, the research was classified as exploratory and descriptive, and, in relation of the approach, quantitative. One questionnaire was applied on 33 Executives and CIOs of the 50 Rio Grande do Norte s organizations that collected the highest taxes of ICMS - Imposto sobre Circulação de Mercadorias on 2000. After the data collecting, cluster analysis and chi-square statistical tools were used for data analysis. The research made clear that the Executives and CIOs of Rio Grande do Norte s organizations have low level of agreement concerning the rules of the NBR ISO/IEC 17799. It also made evident that the Executives and CIOs have its perception toward Information Security influenced by the number of PCs networked and by the number of attacks suffered by the organizations
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O objetivo deste estudo foi estimar a prevalência das mal-oclusões e variáveis a elas associadas, como hábitos deletérios (HD) e as alterações oronasofaringianas (AO), respiração bucal, deglutição atípica e fonação atípica, em crianças com idade de três anos, no Município de Vitória, Espírito Santo, Brasil. A amostra constituiu-se de 291 crianças de ambos os sexos, matriculadas nos Centros de Educação Infantil, selecionadas por meio de amostragem probabilística por conglomerados. A análise de regressão logística indicou maior risco relativo (RR) de crianças com sobressaliência alterada, mordida aberta e mordida cruzada, em apresentar: respiração bucal (RR = 1,89; IC: 1,56-2,03), (RR = 2,46; IC: 2,00-3,02), (RR = 1,45; IC: 1,23-1,72); deglutição atípica (RR = 2,57; IC: 1,87-3,52), (RR = 3,49; IC: 2,53-4,81), (RR = 1,86; IC: 1,46-2,39) e fonação atípica (RR = 2,25; IC: 1,66-3,05), (RR = 3,18; IC: 2,38-4,25), (RR = 1,71; IC: 1,32-2,22), respectivamente. Foi mostrado haver associação entre sucção de dedo e de chupeta com sobressaliência alterada (p < 0,001) e sucção de chupeta e mordida aberta (p < 0,001). Esses resultados indicam que a prevalência das mal-oclusões está associada aos HD e às AO.
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Measures of mortality represent one of the most important indicators of health conditions. For comprising the larger rate of deaths, the study of mortality in the elderly population is regarded as essential to understand the health situation. In this sense, the present study aims to analyze the mortality profile of the population from 60 to 69 (young elders) and older than 80 years old (oldest old) in the Rio Grande do Norte state (Brazil) in the period 2001 to 2011, and to identify the association with contextual factors and variables about the quality of the Mortality Information System (SIM). For this purpose, Mortality Proportional (MP) was calculated for the state and Specific Mortality Rate by Age (CMId) , according to chapters of ICD- 10, to the municipalities of Rio Grande do Norte , through data from the Mortality Information System (SIM) and the Brazilian Institute of Geography and Statistics (IGBE). In order to identify groups of municipalities with similar mortality profiles, Nonhierarchical Clustering K-means method was applied and the Factor Analysis by the Principal Components Analysis was resort to reduce contextual variables. The spatial distribution of these groups and the factors were visualized using the Spatial Analysis Areas technique. During the period investigated, 21,813 younger elders deaths were recorded , with a predominance of deaths from circulatory diseases (32.75%) and neoplasms (22.9 %) . Among the oldest old, 50,637 deaths were observed, which 35.26% occurred because of cardiovascular diseases and 17.27% of ill-defined causes. Clustering Analysis produced three clusters to the two age groups and Factor Analysis reduced the contextual variables into three factors, also the sum of the factor scores was considered. Among the younger elders, the groups are called misinformation profile, development profile and development paradox, which showed a statistically significant association with education and poverty and extreme poverty factors, factorial sum and the variable related to underreporting of deaths. Misinformation profile remained in the oldest old group, accompanied by the epidemiological transition profile and the epidemiological paradox, that were statistically associated with the development and health factor, as well as with the variables that indicate the SIM quality: proportion of blank fields about the schooling and underreporting. It proposed that the mortality profiles of the younger elders and oldest old differ on the importance of the basic causes and that are influenced by different contextual aspects , observing that 60 to 69 years group is more affected by such aspects. Health inequalities can be reduced by measures aimed to improve levels of education and poverty, especially in younger elders, and by optimizing the use of health services, which is more associated to the oldest old health situation. Furthermore, it is important to improve the quality of information for the two age groups
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Coordenação de Aperfeiçoamento de Pessoal de Nível Superior
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The study of Brazilian sedimentary basins concentrates on their rift phase, whereas the Post-rift phase has been considered a tectonic quiescent period. The post-rift sequence of the Potiguar Basin, in the far northeastern Brazil, was once considered little deformed, however several studies have shown how that it was affected by major fault systems. The purpose of this thesis is to characterize the post-rift tectonic. The specific objectives are: to characterize the Neogene and Quaternary sedimentary units that outcrop of the Potiguar Basin; to show how the NW-SEtrending Afonso Bezerra Faults System deformed outcrop rocks in the Basin; to describe soft-sediment deformation in gravels of the Quaternary Alluvial Deposits from Açu River. Facies analyses, grain-size studies, luminescence dating, remote sensing, structural mapping, shallow geophysics (georadar), paleostress and petrography were carried out. The structural mapping and the georadar sections indicated that the Carnaubais and Afonso Bezerra fault systems formed fractures, silicified and non-silicified faults or deformation bands, affecting mainly the Açu, Jandaíra and Barreiras formations. The petrographic data indicate that the strong silicification resulted in a sealant character of the faults. Paleostress analysis indicates that two stress fields affected the Basin: the first presented N-S-trending compression, occurred from the Neocretaceous to the Miocene; the second stress field presents E-W-trending compression, acts from the Miocene to the present. It was verified once the Afonso Bezerra System Faults was reactivated in periods post-Campanian and affects all post-rift lithostratigraphic units of Potiguar Basin, including Quaternary sedimentary covers. The study about soft-sediment deformation structures indicates that they are similar in morphology and size to modern examples of seismically-induced deformation strutures in coarse sediments. TL and OSL ages indicate that sediment deposition and associated soft-sediment deformation occurred at least six times from ~352 Ka to ~9 Ka. Finally these studies demonstrate how recent is tectonics in the Basin Potiguar
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The area studied forms a thin NNE-directed belt situated south of Recife town (Pernambuco state), northeastern Brazil. Geologically, it comprises the Pernambuco Basin (PB), which is limited by the Pernambuco Lineament to the north, the Maragogi high to the south and the Pernambuco Alagoas massif to the west, all of them with Precambrian age. This thesis reports the results obtained for the Cabo Magmatic Province (CMP), aiming the characterization of the geology, stratigraphy, geochronology, geochemistry and petrogenesis of the Cretaceous igneous rocks presented in the PB. The PB is composed of the Cabo Formation (rift phase) at the base (polymictic conglomerates, sandstones, shales), an intermediate unit, the Estiva Formation (marbles and argillites), and, at the top, the Algodoais Formation (monomictic conglomerates, sandstones, shales). The CMP is represented by trachytes, rhyolites, pyroclastics (ignimbrites), basalts / trachy-andesites, monzonites and alkali-feldspar granite, which occur as dykes, flows, sills, laccoliths and plugs. Field observations and well descriptions show that the majority of the magmatic rocks have intrusive contacts with the Cabo Formation, although some occurrences are also suggestive of synchronism between volcanism and siliciclastic sedimentation. 40Ar/39Ar and zircon fission tracks for the magmatic rocks indicate an average age of 102 r 1 Ma for the CMP. This age represents an expressive event in the province and is detected in all igneous dated materials. It is considered as a minimum age (Albian) for the magmatic episode and the peak of the rift phase in the PB. The 40Ar/39Ar dates are about 10-14 Ma younger than published palynologic ages for this basin. Geochemically, the CMP may be divided in two major groups; i) a transitional to alkaline suite, constituted by basalts to trachy-andesites (types with fine-grained textures and phenocrysts of sanidine and plagioclase), trachytes (porphyrytic texture, with phenocrysts of sanidine and plagioclase) and monzonites; ii) a alkaline suite, highly fractionated, acidic volcano-plutonic association, formed by four subtypes (pyroclastic flows ignimbrites, fine-to medium-grained rhyolites, a high level granite, and later rhyolites). These four types are distinguished essentially by field aspects and petrographic and textural features. Compatible versus incompatible trace element concentrations and geochemical modeling based on both major and trace elements suggest the evolution through low pressure fractional crystallization for trachytes and other acidic rocks, whereas basalts / trachy-andesites and monzonites evolved by partial melting from a mantle source. Sr and Nd isotopes reveal two distinct sources for the rocks of the CMP. Concerning the acidic ones, the high initial Sr ratios (ISr = 0.7064-1.2295) and the negative HNd (-0.43 to -3.67) indicate a crustal source with mesoproterozoic model ages (TDM from 0.92 to 1.04 Ga). On the other hand, the basic to intermediate rocks have low ISr (0.7031-0.7042) and positive HNd (+1.28 to +1.98), which requires the depleted mantle as the most probable source; their model ages are in the range 0.61-0.66 Ga. However, the light rare earth enrichment of these rocks and partial melting modeling point to an incompatible-enriched lherzolitic mantle with very low quantity of garnet (1-3%). This apparent difference between geochemical and Nd isotopes may be resolved by assuming that the metasomatizing agent did not obliterate the original isotopic characteristics of the magmas. A 2 to 5% partial melting of this mantle at approximately 14 kbar and 1269oC account very well the basalts and trachy-andesites studied. By using these pressure and temperatures estimates for the generation of the basaltic to trachy-andesitic magma, it is determined a lithospheric stretching (E) of 2.5. This E value is an appropriated estimate for the sub-crustal stretching (astenospheric or the base of the lithosphere?) region under the Pernambuco Basin, the crustal stretching probably being lower. The integration of all data obtained in this thesis permits to interpret the magmatic evolution of the PB as follows; 1st) the partial melting of a garnet-bearing lherzolite generates incompatible-enriched basaltic, trachy-andesitic and monzonitic magmas; 2nd) the underplating of these basaltic magmas at the base of the continental crust triggers the partial melting of this crust, and thus originating the acidic magmas; 3rd) concomitantly with the previous stage, trachytic magmas were produced by fractionation from a monzonitic to trachy-andesitic liquid; 4th) the emplacement of the several magmas in superficial (e.g. flows) or sub-superficial (e.g. dykes, sills, domes, laccoliths) depths was almost synchronically, at about 102 r 1 Ma, and usually crosscutting the sedimentary rocks of the Cabo Formation. The presence of garnet in the lherzolitic mantle does not agree with pressures of about 14 kbar for the generation of the basaltic magma, as calculated based on chemical parameters. This can be resolved by admitting the astenospheric uplifting under the rift, which would place deep and hot material (mantle plume?) at sub-crustal depths. The generation of the magmas and their subsequent emplacement would be coupled with the crustal rifting of the PB, the border (NNE-SSW directed) and transfer (NW-SE directed) faults serving as conduits for the magma emplacement. Based on the E parameter and the integration of 40Ar/39Ar and palynologic data it is interpreted a maximum duration of 10-14 Ma for the rift phase (Cabo Formation clastic sedimentation and basic to acidic magmatism) of the PB
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This study aims to compare the thermal performance of tiles made from recycled material (waste packaging cardboard with aluminized film) with the tiles of fiber and bitumen, fiber cement and red ceramic with the aim of verifying the suitability of tile to be used in hot and humid climate of low latitude. The samples were selected according to the availability from Natal RN market, as they are sold to the consumers. The methodology was based on studies that used experimental apparatus composed of thermal chambers heated by banks of incandescent bulbs, to analyze the thermal performance of materials. The tiles in the study were submitted to analysis of thermal performance, thermophysical properties and absorptance, using chambers of thermal performance, measuring the thermophysical properties and portable spectrometer, respectively. Comparative analysis of thermal performance between two samples of the recycled material with dimple sizes and different amounts of aluminum were made, in order to verify, if these characteristics had some interference on the thermal performance of them; the results showed no significant performance differences between the samples. The data obtained in chambers of thermal performance and confirmed by statistical analysis, showed, that the tile of recycled material have similar thermal performance to the tile of fiber cement. In addition to these tests was carried out the automatic monitoring of a building covered with tiles of recycled material, to verify its thermal performance in a real situation. The results showed that recycled shingles must be used with technical criteria similar to those used for fiber cement tiles, with regard to the heat gain into the building. Within these criteria should be taken into account local characteristics, especially in regions with hot and humid climate, and its use must be associated, according to the literature, to elements of thermal insulation and use of passive techniques such as vented attics, ceilings and right foot higher
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Baixo Vermelho area, situated on the northern portion of Umbuzeiro Graben (onshore Potiguar Basin), represents a typical example of a rift basin, characterized, in subsurface, by the sedimentary rift sequence, correlated to Pendência Formation (Valanginian-Barremian), and by the Carnaubais fault system. In this context, two main goals, the stratigraphic and the structural analysis, had guided the research. For this purpose, it was used the 3D seismic volume and eight wells located in the study area and adjacencies. The stratigraphic analysis of the Valanginian-Barremian interval was carried through in two distinct phases, 1D and 2D, in which the basic concepts of the sequence stratigraphy had been adapted. In these phases, the individual analysis of each well and the correlation between them, allowed to recognize the main lithofacies, to interpret the effective depositional systems and to identify the genetic units and key-surfaces of chronostratigraphic character. The analyzed lithofacies are represented predominantly by conglomerates, sandstones, siltites and shales, with carbonate rocks and marls occurring subordinately. According to these lithofacies associations, it is possible to interpret the following depositional systems: alluvial fan, fluvio-deltaic and lacustrine depositional systems. The alluvial fan system is mainly composed by conglomerates deposits, which had developed, preferentially in the south portion of the area, being directly associated to Carnaubais fault system. The fluvial-deltaic system, in turn, was mainly developed in the northwest portion of the area, at the flexural edge, being characterized by coarse sandstones with shales and siltites intercalated. On the other hand, the lacustrine system, the most dominant one in the study area, is formed mainly by shales that could occur intercalated with thin layers of fine to very fine sandstones, interpreted as turbidite deposits. The recognized sequence stratigraphy units in the wells are represented by parasequence sets, systems tracts and depositional sequences. The parasequence sets, which are progradational or retrogradational, had been grouped and related to the systems tracts. The predominance of the progradation parasequence sets (general trend with coarsening-upward) characterizes the Regressive Systems Tract, while the occurrence, more frequently, of the retrogradation parasequence sets (general trend with finning-upward) represents the Transgressive System Tract. In the seismic stratigraphic analysis, the lithofacies described in the wells had been related to chaotic, progradational and parallel/subparallel seismic facies, which are associated, frequently, to the alluvial fans, fluvial-deltaic and lacustrine depositional systems, respectively. In this analysis, it was possible to recognize fifteen seismic horizons that correspond to sequence boundaries and to maximum flooding surfaces, which separates Transgressive to Regressive systems tracts. The recognition of transgressive-regressive cycles allowed to identify nine, possibly, 3a order deposicional sequences, related to the tectonic-sedimentary cycles. The structural analysis, in turn, was done at Baixo Vermelho seismic volume, which shows, clearly, the structural complexity printed in the area, mainly related to Carnaubais fault system, acting as an important fault system of the rift edge. This fault system is characterized by a main arrangement of normal faults with trend NE-SO, where Carnaubais Fault represents the maximum expression of these lineations. Carnaubais Fault corresponds to a fault with typically listric geometry, with general trend N70°E, dipping to northwest. It is observed, throughout all the seismic volume, with variations in its surface, which had conditioned, in its evolutive stages, the formation of innumerable structural features that normally are identified in Pendencia Formation. In this unit, part of these features is related to the formation of longitudinal foldings (rollover structures and distentional folding associated), originated by the displacement of the main fault plan, propitiating variations in geometry and thickness of the adjacent layers, which had been deposited at the same time. Other structural features are related to the secondary faultings, which could be synthetic or antithetic to Carnaubais Fault. In a general way, these faults have limited lateral continuity, with listric planar format and, apparently, they play the role of the accomodation of the distentional deformation printed in the area. Thus, the interaction between the stratigraphic and structural analysis, based on an excellent quality of the used data, allowed to get one better agreement on the tectonicsedimentary evolution of the Valanginian-Barremian interval (Pendência Formation) in the studied area
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This dissertation presents the results of research developed in the Nísia Floresta-Papeba-Guaraíras Lagoon Complex, located on the south coast of the Rio Grande do Norte State. The main objectives of this dissertation were the stratrigraphic characterization, in detail scale, of the and the coastal dynamics study of the lagoonal deposits sedimentation, as well as the morpho-dynamic analysis of the area. Therefore, an interdisciplinary methodology was adopted, in which all sedimentological, morpho-tectonic and geomorphological data were integrated. Vibracore up to 4m in length were carried out in the lagoons. The referred lagoon complex made of a system of three lagoons that interact through two artificial channels, named Boqueirão and Surubajá. The Guaraíras lagoon, the largest one in the system, corresponds to the estuary zone of the Trairi and Jacu rivers. The sedimentary load brought by these rivers is strongly reworked by tide currents, forming an important net-work of channels and sandy bars inside this lagoon and close to its channel connection with the sea. The stratigraphic units of the area are Cenozoic in age, and are represented by sedimentary rocks of the Barreiras Formation (sandstones, mudstones and conglomerates) and by rocks beach, as well as by siliciclastics sediments related with the fluvial dynamics of tide plain (clay and sandy bars), and coast (sand dunes and beaches). Among the recognized geomorphologic aspects, there are the elements associated with continental enviroments (drainage basins of the Trairi, Baldum and Jacu rivers, coastal tableland supported by the Barreiras Formation), and transitional environments (lagoon complex, dune fields, cliffs, tidal channels and beach rocks lines). The morphotectonic analysis indicates that fauts affect Barreiras Formation sedimentary rocks, with two sets of main lineaments: SW-NE and SE-NW. The anomalies in the drainage net are directly associated with these fault/fracture system, which control and subdivede the low courses of the Trairi and Jacu rivers, at least a tail of their flowing principal courses. The Nísia Floresta, Papeba and Guaraíras lagoons present strong morphological control according to the lineament directions. Taking into account the lagoonal deposits, the sedimentological analyses reflect a sediment distribution related to the interaction of the fluvial and sea processes that act in the study area. The correlated deposits show textural mainly microclastic characteristics of shallow waters, and of currents of low to moderate energy.In general, the Nísia Floresta-Papeba-Guaraíras lagoon Complex, constitutes a very intrinsec group, that undewent important changes in historical times that are reflected in the currents clays. Inaddition to the natural processes that act in this system, we should take into account the antrohopic intervention, which have increased in the past years