40 resultados para Planalto Central, descrição, Brasil
Resumo:
The recent insertion of biodiesel derived from oily vegetables in the Brazilian energetic matrix calls for the study of some aspects that belong to it. The analysis of the carbonized energetic pattern concerns the paradigm of economic development that is constitutionally enshrined sustainable development which make environmental protection compatible with the needs of the economic rationality. This text is structured according to the ideas of modern hermeneutic that sees substantial value in the principles capable of create a harmonious relationship between law and society. The study of the constitutional principles to conduct a legal analysis about the National Program for Production and Use of Biodiesel - PNPB. The aim of the research is the study of PNPB ahead with the constitutional principles governing the economic order. To achieve this end we studied the sustainable development as a constitutional principle. We start with the notion that the thematic principles, and fundamental to understanding the dimension of sustainable development institute, since its concept is closely related to the applications of the principles enshrined in virtually all the constitutional order of the Western world. Then this was the National Energy Policy, initiating the approach by guiding principles of the National Energy Policy to develop the theme of public policy in the energy sector. Therefore, we studied the National Program of Biodiesel Production and Use - PNPB. From a technical introduction to the concept of biodiesel and a brief historical background, analyzing their advantages compared to fossil fuels predominantly used. Then it became a regulatory overview of the Brazilian legislation on the subject, central to understanding the plans and objectives pursued by the Brazilian government with encouraging the production of biodiesel. Finally discussed the tax incentives for production and use of biodiesel in Brazil. From the idea of federalism, characterized the tax as an instrument of state intervention in the economy. And finally it brought the tax incentives of Law No. 11.116/2005 in the face of the constitutional principles of economy and tax, and tax incentives from projects related to the Kyoto Protocol
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The present work aims to analyze the several proportional electoral systems from the contemporaries democracies in order to, in the end, purpose a system that better fits to the constitutional Brazilian order. In this direction, we pursued to indicate the main virtues and imperfections in proportional electoral systems in use in more than two hundred countries, especially relating to the positive and negative effects that these systems inject in the party systems, in the governability and in the representativity. In order to collect elements, and also before getting to the work s main point, other issues were approached, even in a shortened way. Nevertheless, in a position taking, we conclude the work opting for a proportional electoral system that potencializes the constitutional principles of representativity and governability as well as prints a party system strong and strict, once these are the depositaries of a democracy compromised with the Brazilian society
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This Dissertation examines outsourcing in Bank of Brazil SA, the state of Paraiba. The central research question is to what extent this flexibility of labor relations incorporates items claimed by ´recent´ Decent Work Agenda of the International Labour Organization (OIT) or, on the contrary, the ´epidemic´ of outsourcing makes it even more challenging the world of work in the third millennium. The research hypothesis is that the Bank of Brazil has a growing subcontracting / outsourcing of labor (companies and individuals) and that not only contributes to the deterioration of working conditions, but also opposes the Work Agenda decent. Aiming to prove or disprove the hypothesis, the study includes a survey and secondary field. The literature review focuses on the trend towards casualization of labor in capitalism, and yet, in an effort to systematize data and analysis on ´outsourcing´ from the viewpoint of different actors. This theoretical framework is anchored in important classical sources and present that address the topic in the world and in Brazil. The field research was conducted with the actors related to the theme of ´outsourcing´ the Bank of Brazil - Paraiba, precisely branch managers, permanent employees of the bank, union representatives (bank workers), union bank and outsourced. The results confirm, in part, the study hypothesis, by demonstrating that there are several meanings and forms of precariousness that the contractors surveyed are submitted, highlighting the issue of salaries, the work environment, union representation and health worker. All these themes, each for himself, are contemplated by the Decent Work Agenda of the ILO and show, according to field research, rather fragile
Resumo:
The literature about the Geography teaching has shown that most male and female teachers of this subject go on guiding their teaching practice based on the traditional Geography fundamentals, whose main characteristic consist in the description of places. The incorporation of scientific standards that change the old principles and concepts have not been happening, unless in a punctual way. The overcoming of the traditional Geography, related to the aspects accepted by the scientific field have not happened in Brazil yet, not only because of certain obvious obstacles, as the literature has been pointed out but also by symbolic obstacles, which block the incorporation of the new, of the non habitual action. One of those obstacles that motivated the accomplishment of this study was the social representations that are theoretically studied here under the perspective developed by Serge Moscovici. Then, the focus of this doctorate study is concentrated in the apprehension of the content and structure of the social representation of teaching of Geography and its relation with the habitus that gives form and social visibility to the ones who are teachers of that subject in Teresina. The consecution of this work was especially based on the Pierre Bourdieu´s praxiology, mainly on the concepts of social field, habitus and capital, as well as the theory of social representations, specifically on the approach of central nucleus developed by Jean-Claude Abric and Jean-Claude Flament. The initial hypothesis pointed out the existence of a Geographer´s primary habitus built through the development process of the geographic science field in Brazil, as a basis of production of a social representation of teaching geography . That representation, however, would act as a symbolic obstacle to the incorporation of the new scientific contents and pedagogical practice, which require from the teacher investigative and questionable attitude in the presence of the reality and contents approached in the classroom. That initial hypothesis laid on the theoretical purpose that it has been developed by Domingos Sobrinho (1997), which states that there is a narrow relationship between the habitus and social representation. The study was developed with male and female teachers of Geography from public schools of Teresina. The methodology involved the use of a questionnaire, the free-word association technique and deep interviews. The achieved results showed the presence of a complex process of representational construction and its articulation with a habitus produced by the synthesis of several situational and cultural referents, from among of them we can point out an insertion in a social field of practice exclusively related to the teaching and the reproduction of a professoral teaching (SILVA, 2003), built through the school development process, which those male and female teachers were exposed. The initial hypothesis that considered the local reproduction of a primary habitus of the Geography was denied, therefore, it was verified that there is not in Teresina the production/reproduction of the structures, rules and practice of the national scientific field, in which this subject is inserted. Hence, the incorporation of the new patterns of the geographic scientific knowledge is difficult because of the inexistence of a scientific habitus, that is, mental schema systems that would let the teachers mentioned above connect themselves appropriately to the science and its practices. So, it has gotten a social representation of teaching geography based on contents strictly related to the reproduction of structures, mental schema from the educational field which attach themselves to the hegemonic pedagogical practices in the national scope
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L'objectif de cette étude est de comprendre la relation entre les situations didactiques faisant appel aux connaissances historiques et la construction de l'identité personnelle pour les enfants dans l'éducation de la petite enfance. Sa question centrale se demande si les connaissances sont offrent des contributions à la construction de l'identité personnelle par les enfants de la petite enfance. Se distingue, lui aussi, entend contribuer à élargir le débat sur l'enseignement et l'apprentissage des thèmes historiques dans l'éducation des enfants, et permettre un dialogue avec d'autres enseignants dans cette étape de l'éducation. Ont été analysés par des principes théoriques et méthodologiques de qualité et a assumé les orientations méthodologiques de la recherche collaborative. Il a été constaté que la systématisation des situations didactiques impliquant la connaissance historique dans l'éducation de la petite enfance contribue à la construction de l'identité personnelle de l'enfant. Ceci, pour prendre possession de ces connaissances, ils recueillent des renseignements qui permet le plus large éventail de relations, afin de comparer les pratiques culturelles de son temps avec des pratiques à d'autres moments. Ainsi orientée, l'enfant cherche à raconter son histoire avec le thème historique à laquelle elle a eu accès, d'organiser et de construire des réponses des explications sur leur environnement et de lui-même. Tout cela montre à la réalisation que le processus d'internalisation des connaissances historiques de l'enfant est construit comme un sujet et, par conséquent, cette connaissance peut être conçu comme un médiateur dans la formation de l'identité personnelle
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This work aims at studying the policies of teaching training and their impact in the actors and in the education systems of the countries in which these policies were implemented into the context of neoliberal reforms. We particularly studied these policies in three Latin America countries: Argentina, Brazil and Chile. The policies studied here are the ones implemented from the 90 s. However, the horizon of this study is at the beginning of the 80 s, period that starts one of the four intervention initiatives of education here studied: The Main Project of Education For Latin America and Caribbean (PROMEDLAC), which in 2002 goes into a new stage and it is called Regional Project of Education for Latin America and Caribbean (PRELAC), worked out by UNESCO as a request of government representatives of countries of the region, based on the suggestions of Declaration of Mexico , signed by them in 1979. These suggestions will be in the base of the other three initiatives: The Education For All (EPT); Ibero-American Conferences of Education (CIE) and The Hemisphere Action Plan of Education (PAHE), whose documents are the base to the production of an abundant legislation and normatization on education that created the parameters on which the policies of education reforms were worked out and implemented and the dynamism of our education systems from the last two decades of the twentieth century on. All these initiatives intend to work with objectives, projects and programs that, in some cases, in isolation or in groups, are under influence of their actions in a way that frequently it is difficult to identify which of them is the main responsible for some advances. It is important to stand out that not all of the suggestions produced by these initiatives were implemented as policies, and many of them to be implemented were changed in such a way that they were distorted, even they were a result of a multilateral deal, each country gave to them its own interpretation. Moreover, in all these processes the teaching entities had and keep having a fundamental role. The evidences, result of the evaluations of each initiative, show that education policies implemented produced advances in several aspects. They are still not the ideal ones, in truth, but they do exist. In relation to the teaching questions, there were and are still being implemented multiples and varied actions that did not have the expected impact in the education systems of the countries, objects of this study, but, many of them that go on, are promising and start to have a positive impact into the education systems. Even so, the teaching subject matter, even playing a central role in the agenda of all countries of the region, still represents one of the big challenges to the advance and improvement of our education systems
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This paper treats confessional printings as a non formal space for the female education. It reflects on the importance of the woman s role to the diffusion of Protestantism in general, and its Presbyterian trend in particular, besides commenting on the proliferation of printings at the First Republic and its relation with education. In this study, Brazilian Northeastern is seen as a relevant space to the diffusion of Protestantism in Brazil; especially on what concerns the relations between Rio Grande do Norte and Pernambuco. Thereby some fountains were fundamental, as the confessional printings, that is, newspapers, magazines, prospects and other materials recollected in archives located in Natal/RN and Recife/PE, and São Paulo. It was also provided a brief incursion on Portuguese confessional printings kept in Oporto, PT. New Cultural History was chosen as theoretic-methodological guide, franchising ways inside the history of book and reading with the help of concepts like Interdependence, Social Configuration (ELIAS, 1993, 1994) and Representation (CHARTIER, 1990), considering that the survey worked out culture-manufactured products that is, intentional materials. It is well known that publishing, or better, the dissemination of printed material used to be associated to Protestants missionary practices since Reform began and, as what concerns the investigated period, in Portuguese and Brazilian lands indistinctly. Printing material in general books, booklets, fragments, as well as the press itself played a central role in divulging reformed ideas, their social options and the means of being and intervening in the world. In this regard, the confessional printings established themselves as an educative, although non schooled, informal space, but, all considered, relevant, seen that they dialogue with another important demand of that social group: formal, literate education. Because it dealt with the diffusion of a printed culture supported by the written word, it required of that group a different modus operandi: formal education. The first letters schools at first, then the high schools later represented spaces established for the circulation of printing material in order that they should be read, divulged and comprehended. This survey intends at last to take a look at Protestantism which, in this context of self-affirmation, reserved a specific place to woman by working out a non formal educational proposal disseminated by printing material. Three models were highlighted in the reformed proposal: Christian education in itself, household education, whose references of motherhood and care towards the neighbor were present and, at last, education to the public space, with emphasis on the practice of teaching. This study also offers a brief dialogue between Brazil and Portugal because, when some periodic printing, book or something like that got to be published in one margin of the Atlantic Ocean, the other margin surely was affected by that feat, received it, divulged it, corroborating the argument in support of the circulation of these printings. It was not only the same language that survived in both maritime coasts; some protestant specificities also crossed out along that sea
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The present paper is a doctorate thesis, in the area of Education, that has as a goal to describe and to reflect on the construction/systematization of a relation between family and institution of Childhood Education, in favor of sharing the care and education actions of children, in the context of creation of a County Center of Childhood Education, located in the city of Natal-RN. Our intension with this paper is to share some of the ideas and actions collectively constructed by this experience, with the intention of bringing a contribution for the thematic debates concerning Childhood Education - as modality of education, in a general way; and the relations between families and Institutions of Childhood Education, in a more specific way. The paper presented here is endorsed by the postulates of the qualitative research with characteristics of a research-action, having as main instruments of the data construction the open or half-structuralized interviews, the personal notebook of registers, the participant s index cards characterizing the children and comments. Authors as Aries (1981); Bassedas, Huguet and Solé (1999); Bhering and Blatchford (1999); Brasil (1998); Bujes (2001); Didonet (2002 - 2003); Formosinho (2007); Gómez (2000); Heywood (2004); Kramer (2005); Marchesi and Martín (2003); Marschal and Zohar (2006); Thiollent (2004); Tiriba (2006), amongst others, had theoretically based this paper. The experience described here points to the possibilities of sharing the care and education actions between family and Institution of Childhood Education, emphasizing the relevance of participative praxis in the interior of the institution, so that its job can propitiate this sharing with the families, throughout activities as meetings, lectures, workshops, participation in didactic projects, open expositions to the community, commemorative parties and valuation of the local culture, amongst other chances of dialogue and interaction between the educative institution and the families
Resumo:
It is a case study that reports the construction of metal truss bridge in the river Potengi in Natal, Rio Grande do Norte, between the years 1912 and 1916. From testimonials on steel bridges in Brazil and worldwide including foundations. Documentary research from procurement of projects and contracts was performed. A chronology of construction, with a description of the equipment used and its original budget with the Brazilian government. Still, we used interviews and surveys with experimental sampling / testimonies, laboratory tests. This study aims to analyze historically and technically the Bridge over the River Potengi, emphasizing primarily the construction process, the qualities and characteristics of the materials used and the technological, chemical, mineralogical and microstructural properties of cement and concrete used in its construction. Taking as conclusions that cements pozolônicos ensured a good durability to the concrete in a hundred-year period and that the solution employed with the compressed air caissons was right
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A Indústria Farmacêutica é uma das mais competitivas indústrias do mundo contemporâneo, e um dos seus principais desafios está na comercialização de seus medicamentos, que na sua maioria depende da prescrição médica. O objetivo deste estudo é identificar as estratégias de avaliação de desempenho utilizadas pela Indústria Farmacêutica de origem multinacional que atua no nordeste Brasileiro e o papel dos seus gerentes, para avaliar os propagandistas vendedores de medicamentos. Para tanto, buscouse reunir elementos para uma abordagem satisfatória que contemple a complexidade da temática pesquisada: Avaliação de Desempenho, Estratégias da Indústria Farmacêutica, Propaganda Médica e Competências dos Propagandistas de Medicamentos. A temática justifica-se em razão da importância estratégica dos propagandistas de medicamentos para a indústria farmacêutica, que é uma das indústrias que mais investe em pesquisa na atualidade, e contribui para melhorar a qualidade de vida e a saúde humana. A metodologia é caracterizada como um survey, de natureza quali-quantitativa. O objeto de estudo é composto pelas empresas farmacêuticas multinacionais de origem Americanas, Europeias e Asiáticas, associadas à INTERFARMA que atuam no Nordeste do Brasil. A coleta de dados foi realizada através de um questionário fechado (instrumento de pesquisa), composto por 5 perguntas fechadas que abordam a temática central dessa dissertação, 27 afirmativas para medir a concordância(escala likert) e 1 tabela contendo 46 competências, aplicado junto a gerentes da indústria farmacêutica. A análise dos dados foi feita por meio das técnicas de estatística descritiva e uma análise quantitativa para estabelecer o Ranking Médio (RM) para a parte do questionário que utilizou escala tipo Likert de 5 pontos para mensurar o grau de concordância dos respondestes. Através dos resultados desta pesquisa foi possível identificar as estratégias de avaliação de desempenho, utilizadas pelas empresas farmacêuticas, que atuam no Nordeste do Brasil, na gestão dos propagandistas vendedores de medicamentos, e identificar as competências essenciais dos propagandistas de medicamentos, na percepção dos gestores. Os resultados demonstraram que a Indústria Farmacêutica desenvolve e utiliza várias estratégias para medir e avaliar o desempenho dos propagandistas de medicamentos no Brasil, assim como em outros países, e que na percepção dos gerentes da Indústria Farmacêutica existem competências consideradas essenciais ao bom desempenho profissional dos propagandistas de medicamentos da indústria farmacêutica, contribuindo de para avanço do conhecimento deste tema
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This research has the goal to analyze the urban setting of the Planalto neighborhood, in Natal /RN, seeking to unravel the processes, agents and contradictions associated with the production of the space. The choice of neighborhood is justified by the observation that changes in its urban setting have been growing in speedy way. We highlight the performance of the housing market, in partnership with the state, and the construction of condominiums and buildings closed by the housing program Minha Casa, Minha Vida. This has favored the reproduction of a new " urban reality in the neighborhood, setting an urban standard that differs from the original morphology, seen as peripheral within the urban dynamics of the city. The research is a qualitative study, through documents, interviews with stakeholders, and photographic documentation. In this perspective , we seek to understand the current phase (2000s) the production of space in the neighborhood process through the development of the housing market , as an extension of the urban development in central zone of Natal/RN, analyzing the performance of agents and their producers the "new " uses redefining the "old ". Thus, it can be seen that there is in the neighborhood, urban reality in a pluralistic constitution, from the existence of different social classes inhabiting the same space. On this way, the city is produced from the appropriation of space by different social classes, although due to the economic condition of each of them
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This study investigated the influence of intrinsic and extrinsic factors on the feeding ecology and foraging behavior of the whiptail lizard Ameivula aff. ocellifera, a new species widely distributed in the Brazilian Caatinga, and that is in process of description. In attendance to the objectives, the Dissertation was structured in two chapters, which correspond to scientific articles, one already published and the other to be submitted for publication. In Chapter 1 were analyzed the general diet composition, the relationship between lizard size and prey size, and the occurrence of sexual and ontogenetic differences in the diet. Chapter 2 contemplates a seasonal analysis of diet composition during two rainy seasons interspersed with a dry season, and the quantitative analysis of foraging behavior during two distinct periods. The diet composition was determined through stomach analysis of lizards (N = 111) collected monthly by active search, between September 2008 and August 2010, in the Estação Ecológica do Seridó (ESEC Seridó), state of Rio Grande do Norte. Foraging behavior was investigated during a rainy and a dry month of 2012 also in ESEC Seridó, by determining percent of time moving (PTM), number of movements per minute (MPM) and prey capture rate by the lizards (N = 28) during foraging. The main prey category in the diet of Ameivula aff. ocellifera was Insect larvae, followed by Orthoptera, Coleoptera and Araneae. Termites (Isoptera) were important only in numeric terms, having negligible volumetric contribution (<2%) and low frequency of occurrence, an uncommon feature among whiptail lizards. Males and females did not differ neither in diet composition nor in foraging behavior. Adults and juveniles ingested similar prey types, but differed in prey size. Maximum and minimum prey sizes were positively correlated with lizard body size, suggesting that in this population individuals experience an ontogenetic change in diet, eating larger prey items while growing, and at the same time excluding smaller ones. The diet showed significant seasonal differences; during the two rainy seasons (2009 and 2010), the predominant prey in diet were Insect larvae, Coleoptera and Orthoptera, while in the dry season the predominant prey were Insect larvae, Hemiptera, Araneae and Orthoptera. The degree of mobility of consumed prey during the rainy seasons was lower, mainly due to a greater consumption of larvae (highly sedentary prey) during these periods. Population niche breadth was higher in the dry season, confirming the theoretical prediction that when food is scarce, the diets tend to be more generalized. Considering the entire sample, Ameivula aff. ocellifera showed 61,0 ± 15,0% PTM, 2,03 ± 0,30 MPM, and captured 0,13 ± 0,14 per minute. Foraging mode was similar to that found for other whiptail lizards regarding PTM, but MPM was relatively superior. Seasonal differences were verified for PTM, which was significantly higher in the rainy season (66,4 ± 12,1) than in the dry season (51,5 ± 15,6). It is possible that this difference represents a behavioral adjustment in response to seasonal variation in the abundance and types of prey available in the environment in each season
Resumo:
The provident rights were results of intense fights in between the capital and work, claiming the interventions of the state for the creation of an ample social protection system. In Brazil the law, Providence Social mark, dated 1923, from then on, the advances and extensions were many, of this diverse categories of politics. Mean while, in the 1990 s, the Brazilian government adopted the examples of other developed countries, the new pattern that hinted the realization of substantial changes on the states purpose, the reached rights and the proper organization of working classes. For the Social Providence, the principal loses turned out in 1998 and 2003; respectively in FHC governments and Lula, with the realization of two counter reforms that restricted the provident rights and motivated the privatization of public providence. In the scenery, the CUT, one of the representative organizations from working classes, founded in 1983, that has always itself with changed direction, from fighting to negotiating. This inflection determined the proposition of the center before the offers of the counter reforms, of Social Providence. The present work has the objective to analyze the social politic content of the fights from Brazilian union movement in the period of the conquests and disassembled rights and, to analyze the proposition, acting and offers from CUT in the counter reform period from Providence in the Government FHC and Lula. To perform this study beyond the essential bibliographical revision to found and deepen the subject, we use, the documental search through the internet pages, resolutions, informations and others publications from CUT. Using CUT in the governments worked in an elegant way, the FHC government against-reforms, showed itself through diverse actions, even though they didn t have homogeneous inside, contrary the neoliberalists politicians from this government, also the offers and precaution changers. While during the reign of Lula it shoved itself priority negociative and propositive
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Until some years ago, weathering geochronology was primarily based on the K-Ar and 40Ar/39Ar dating of supergene minerals. Recent advances in the analysis of supergene goethite by the (U-Th)/He method expanded the number of suitable minerals for such purpose, as well as the time of application for weathering geochronology. This study represents the first systematic approach in Brazil, combining both the 40Ar/39Ar e (U-Th)/He methodologies to improve the knowledge on the weathering and the age of nonfossiliferous sediments. Supported by geologic and geomorphologic correlations, we identified different types of weathering profiles occurring in the interior and coastal areas of northeastern Brazil. These profiles were correlated to main regional geomorphological domains: the Borborema Plateau , the Sertaneja Depression , and the Coastal Cuestas and Plains, and respective planation surfaces, which study is fundamental to understand the landscape evolution of the northern portion of the eastern Borborema Province. The depth and stratigraphic organization of the weathering profiles in each of the geomorphological domains permitted to establish that: (i) the profiles on the highlands that cap the Borborema Surface are deeper (up to 100 m) and can be considered as typical lateritic profiles; (ii) on the lowlands that form the Sertaneja Surface , the weathering profiles are shallow and poorly developed (2-5 m deep); (iii) the profiles along the coastal area are moderately developed (up to 25 m deep), and are characterized by thick saprolites and mottle zones. Aiming to establish the timing of the evolution of northeastern Brazil, we studied 29 weathering profiles representing distinct topographic levels of the Borborema Province, from the highlands to the coast, through the analysis of 248 grains of supergene manganese oxides using laser step-heating 40Ar/39Ar geochronology. Additionally, we applied the (U-Th)/He method in 20 weathering profiles, by dating 171 grains of supergene iron oxides and hydroxides. Geochronological results for 248 grains of manganese oxides analyzed by the 40Ar/39Ar method indicate that the weathering profiles in the study area record the history of weathering from the Oligocene to the Pleistocene, with ages in the order of 31.4 ± 1.0 Ma to 0.8 ± 0.4 Ma. Dating of 171 grains of goethite by the (U-Th)/He method yielded ages ranging from 43.2 ± 4.3 Ma to 0.8 ± 0.1 Ma, suggesting the weathering processes last from the Eocene to the Pleistocene. The precipitation of supergene goethite in this interval confirms the age of the weathering processes identified from the manganese oxides record. 105 goethite grains from 8 different occurrences of the Barreiras Formation were dated by the (U-Th)/He method. Five grains collected from the cement in the Barreiras Formation sandstones, in the Lagoa Salgada and Rio do Fogo coastal cuestas, yielded ages of 17.6 ± 1.8 Ma, 17.3 ± 1.7 Ma, 16.3 ± 1.6 Ma, 16.2 ± 1.6 Ma and 13.6 ± 1.4 Ma. Results of 69 goethite grains from authigenic pisoliths collected in 7 different localities also yielded concordant ages, varying from 17.8 ± 1.8 to 7.5 ± 0.8 Ma. Results obtained from 31 detrital grains are concordant in 3 distinct localities (Lagoa Salgada, Praia da Garças e Ponta Grossa); they vary in the range of 43.2 ± 4.3 to 21.6 ± 2.2 Ma, and indicate that the maximum age for the Barreiras Formation deposition is around 22 Ma. 40Ar/39Ar results for 15 manganese oxides grains associated with the Barreiras Formation weathering profiles, in 3 different localities, vary from 13.1 ± 0.9 to 7.7 ± 0.4 Ma, in the same range of ages obtained by the (U-Th)/He method. The systematic application of the 40Ar/39Ar and (U-Th)/He methods, respectively for manganese oxides and goethites, show that the Barreiras Formation sediments were already deposited since ca. 17 Ma, and that the weathering processes were active until ca. 7 Ma ago. The ages obtained from manganese oxides collected in the Cenozoic basalts (Macau Formation) also reveal a weathering history between 19 and 7 Ma, pointing to hot and humid conditions during most of the Miocene. 40Ar/39Ar ages yielded by manganese oxides associated with the Serra do Martins Formation vary from 14.1 ± 0.4 to 10.5 ± 0.3 Ma. On the other hand, (U-Th)/He ages from iron oxides/hydroxides collected in the Serra do Martins Formation mesas vary from 20.0 ± 2.0 to 5.5 ± 0.6 Ma, indicating that those sediments are older than 20 Ma. 40Ar/39Ar and (U-Th)/He results produced in this study are in agreement with paleoclimatic interpretations based on stable isotopes and clay index values measured in the Atlantic Ocean sediments, validating the use of weathering geochronology to investigate paleoclimatic variations. The direct dating of the Barreiras Formation permitted, for the first time, confident inferences on the age of the brittle deformation recorded by this sedimentary unit in the Rio Grande do Norte and Ceará states. The first event, syn-deposition, occurred during the early Miocene; an younger event, related to the post-depositional deformation of the Barreiras Formation, is associated with tectonic activity from the very early Miocene to the Holocene. In agreement with data from other areas, results obtained in this study reveal that the depth and complexity of the weathering profiles reflect the time of exposition of such areas to the weathering agents close to the surface. However, there is no clear relationship between ages vs. altitude. The depth and the stratigraphic organization of weathering profiles in northeastern Brazil, contrary to the southeastern Brazil pattern, do not vary toward the coast. In our study area, field observations reveal the presence of ancient, thick and complex lateritic profiles preserved in the sedimentary mesas on the Borborema Plateau, as younger, narrow and incipient ones occur in the dissected areas. Geochronological results obtained for these profiles yielded older ages on the high altitudes, and younger ages in the lowlands, suggesting the scarp retreatment is the most reliable model to explain the regional landscape evolution. However, in the coastal lowlands, the relatively older ages obtained indicate that more complexes processes were involved in the modeling of the local relief
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The Xaréu Oil Field, located in the center-southern portion of the Mundaú Sub-Basin (eastern portion of the Ceará Basin), is characterized by a main Iramework of NW-trending and NE-dipping faults. The faults in the Xaréu Oil Field, among which the Xaréu Fautt stands out, are arranged according to an extensional-listriclan, rooted on a detachment surface corresponding to the Mundaú Fault, the border fautt of Mundaú Sub-Basin. During the tectonic-structural evolution of the Xaréu Oil Field and the Mundaú Sub-Basin, the Mundaú Fault played a crucial role on the control of the geometry of both compartments. The main carbonatic unit in the Xaréu Oil Field, named the Trairí Member(Paracuru Formation of Late Aptian to Early Albian age), contains the largest oil volume in the field, concentrated in structurally-controlled accumulations. The Trairí Member is composed by a variety of carbonatic rocks (massive, bedded or laminated calcilutites, ostracodites, calcarenites and carbonatic rudites, all of them presenting variable degrees of dolomitization). The carbonatic rocks are interbedded into thick packages of black shales and marls, besides local beds of siliciclastic conglomerates, sandstones, siltnes and argillites. From the spatial association and the genetic relationships between the carbonatic and siliciclastic units, it is possible to group them in three lithofacies associations (Marginal Plain, Ramp and Lacustrine Interior) that, together, were developed in a lacustrine system associated to a marginal sabkha. Structural studies based on drill coresthat sample the Trairí Member in the Xaréu Oil Field allowed to characterize two generations of meso- to microscale structures: the D1 group presents a typical hydroplastic character, being characterized by intra/interstratal to oblique-bedding shear zones. The hydroplastic character related to these structures allowed to infer their development at an early-lithilication stage of the Trairí Member, leading to infer an Early Cretaceous age to them. The second group of structures identified in the drill cores, nominated D2 and ascribed to a Neogene age, presents a strictly brttle character, being typilied by normal faults and slickenfibers of re-crystallized clayminerals, ali olthem displaying variable orientations. Although the present faults in the Xaréu Oil Field (and, consequently, in the Mundaú Sub-Basin) were classically relerred as struetures of essentially normal displacement, the kinematics analysis of the meso-to microscaie D1 struetures in the drill cores led to deline oblique displacements (normal with a clockwise strike-slip component) to these faults, indicating a main tectonic transport to ENE. These oblique movements would be responsible for the installation of a transtensive context in the Mundaú Sub-Basin, as part of the transcurrent to translormant opening of the Atlantic Equatorial Margin. The balancing of four struetural cross-sections ofthe Xaréu Oil Field indicates that the Mundaú Fault was responsible for more than 50% of the total stretching (ß factor) registered during the Early Aptian. At the initial stages of the "rifting", during Early Aptianuntil the Holocene, the Mundaú Sub-Basin (and consequently the Xaréu Oil Fleld) accumulated a total stretching between 1.21 and 1.23; in other words, the crust in this segment of the Atlantic Equatorial Margin was subjeeted to an elongation of about 20%. From estimates of oblique displacements related to the faults, it ws possible to construct diagrams that allow the determination of stretching factors related to these displacements. Using these diagrams and assuming the sense 01 dominant teetonictransport towards ENE, it was possible to calculate the real stretching lactors related to the oblique movement 0 of the faults in the Mundaú Sub-Basin. which reached actual values between 1.28 and 1.42. ln addnion to the tectonic-structural studies in the Xaréu Oil Field, the interpretation of remote sensing products, coupled wnh characterization of terrain analogues in seleeted areas along the northern Ceará State (continental margins of the Ceará and Potiguar basins), provided addnional data and constraints about the teetonic-structural evolution of the oil lield. The work at the analogue sites was particularly effective in the recognition and mapping, in semidetail scale, several generations of struetures originated under a brittle regime. Ali the obtained information (from the Xaréu Oil Field, the remote sensor data and the terrain analogues) were jointly interpreted, culminating with the proposnion of an evolutionary model lor this segment of the Atlantic Equatorial Margin; this model that can be applied to the whole Margin, as well. This segmentof the Atlantic Equatorial Margin was delormedin an early E-W (when considered lhe present-day position of the South American Plate) transcurrent to transform regime with dextral kinematics, started Irom, at least, the Early Aptian, which left its record in several outcrops along the continental margin of the Ceará State and specilically in the Xaréu off Field. The continuous operation of the regime, through the Albian and later periods, led to the definitive separation between the South American and African plates, with the formation of oceanic lithosphere between the two continental blocks, due to the emplacement off spreading centers. This process involved the subsequent transition of the transcurrent to a translorm dextral regime, creating lhe Equatorial Atlantic Oceano With the separation between the South American and African plates already completed and the increasing separation between lhe continental masses, other tecton ic mechanisms began to act during the Cenozoic (even though the Cretaceous tectonic regime lasted until the Neogene), like an E-W compressive stress líeld (related to the spreading olthe oceanic floor along lhe M id-Atlantic Ridge and to the compression of the Andean Chain) effective Irom the Late Cretaceous, and a state of general extension olthe horizontal surface (due to the thermal uplift ofthe central portion of Borborema Province), effective during the Neogene. The overlap of these mechanisms during the Cenozoic led to the imprint of a complex tectonic framework, which apparently influenced the migration and entrapment 01 hydrocarbon in the Ceará Basin