Estudo da funcionalidade de espécies comestíveis do semiárido nordestino e estratégias para sua utilização como ingredientes para fins alimentícios

The Brazilian caatinga is characterized by low annual rainfall and arid soils. Several cactaceae, either native or adapted species, grow in this semi-arid region, including the prickly pear (Opuntia fícus indica) and facheiro ((Philosocereus pachycladus Ritter) which produce underexploited edible fruits. In addition to these species, the algaroba is a leguminous with little studied technological applications and bioactive potential so far. Therefore, this research aims to investigate the physicochemical, bioactive and functional attributes of the prickly pear and facheiro fruit pulps and the algaroba flour. Specifically, this study approaches the physicochemical characterization, total phenolic compounds (TPC) and the betalain identification and quantification by HPLC-DAD-ESI-MS. It is also investigated the DPPH antioxidant capacity and the antienzymatic activities against alpha-amylase and alphaglucosidase of water and ethanolic extracts of these food material. In order to address their potential to be used as food ingredients, juice blends prepared with mixtures of cajá and prickly pear, biofilms with facheiro and cereal bars with algaroba flour were elaborated and analyzed. The prickly pear fruits presented low acidity and high sugar content when compared to facheiro. The Philosocereus pachycladus Ritter fruits had higher protein and ash content, but the algaroba flour was the species with higher protein and sugar content among all. The algaroba flour also presented outstanding food fiber content, which reveals its potentiality to be used as a natural intestinal regulator. The TPC of water and ethanol extracts ranged from 3.87 to 16.21 mg GAE/100g for algaroba flour, 79.24 to 110.20 GAE/ 100g for prickly pear and 412.23 to 539.14 mg GAE/100g for facheiro. The 70% (w/v) ethanol extract reached the highest DPPH antioxidant activity, which was linearly correlated to its high TPC content. In regard to the enzymatic inhibitory activities, the best performance was observed for the prickly pear extracts which presented a moderate inhibition for both investigated enzymes, but interestingly, no alpha-glucosidase inhibition was observed for facheiro extracts. This work shows, for the first time in the literature, the functional attributes of facheiro fruits, as well as the presence of betacianins and isobetanin in the pulp of this exotic fruit. When it comes to the food products developed here, the sensory attributes that better described the juice blend cajá-prickly pear were sweetness, acidity, color yellow-orange, body, turbidity and cajá flavor. The discriminative test applied for cereal bars produced with and without algaroba revealed that the texture was the only sensory attribute that differed (p<0.05) between these two samples. It was also observed that the addition of facheiro extracts did not influence the visual characteristics of the biofilms. Overall, this work unveils the physicochemical and bioactive attributes of these commercial and technologically underexploited species widely found in the Brazilian caatinga and presents alternatives for their rational use

O imaginário da mediunidade no processo de escritura em Fernando Pessoa

The answer to creating a fictional world? Repulsion or form of reaction to an outside world? Mental illness, whose brand can be symbolic simulation or depersonalization? Hard to take a stand when the deed is a poet Fernando Pessoa as what is at stake. Notes Schlafman Léo (1998) who, at the age of 20 years, Fernando Pessoa wrote in English, in his diary, "One of my mental complications is the fear of madness, which in itself already is crazy." What rid of madness, notes Robert Bréchon (1986), was the taste of the game and was playing it for your writing. Even though it has rid the madness, the poet does not quit seeking explanations - or provide it - for the phenomena much bother him, or defined.'s where we come across the alignment of Fernando Pessoa within philosophical as occultism and reading about psychological and mental disorders treated. paths were pursued by him to explain the existence of his heteronyms and its entry process. This work therefore presents main objective: to analyze the personal papers of Fernando Pessoa, whose outstanding feature is the presence of occult and alleged mediumship demonstrations held in response to non-literary and heteronímicas. Therefore, I focused on specific goals, which are: a) to study the speech of Fernando Pessoa on his mediumship / occult b) analyzing specific texts that are, for the poet, psychic demonstrations, c) study of a series of excerpts personal letters in which Fernando Pessoa suggested to be a medium. Admittedly, this essay will touch many arguments already made by scholars and experts of Fernando Pessoa, but consider the possibility of developing issues and contribute to the critical fortune of the poet. We assume that announces the Portuguese scholar Jerome Pizarro (2006), one of the greatest scholars of the work Pessoan: those interested in Fernando Pessoa be lost in the maze created by him. It is the image of a person-Minotaur, devouring all but, holding us in its labyrinthine tessitura, as marked by mystery. Will draw on our analysis, a theory aligned themselves to objects of research, whose main authors are Sigmund Freud (1908) Carl Jung (1991.1996). Gaston Bachelard (1996), Helena Blavatsky (2008), among others

No céu da boca das gentes, tem estrela e maravilhas: atualização e permanência das narrativas populares nos contos de enganar a morte

This current study consists in an analysis of the work Contos de enganar a morte (2004), of the novelist, illustrator and researcher of popular culture Ricardo Azevedo, aiming to highlight aspects and elements present in this work which show the update and the permanence of traditional popular narratives, widespread by orality, especially those collected by the Luís da Câmara Cascudo in Literatura oral no Brasil (1984), linked to the category of the Cycle of the Death and Tales of the Deceived Demon. It is argued that the symbolic, playful, humor and aspects of orality, evident in these narratives are cultural possessions own of a popular tradition that diffuses, is updated and maintained by the memory of handmade anonymous narrators (BENJAMIN, 1994), poets and brazilian singers of cordel, holders of the traditional knowledge not established, but polyphonic, dialogical and democratic in essence (BAKHTIN, 1996). Still, alongside the people who know and counts the stories of Trancoso and Fairies, the tale, as a written literary genre, has allowed to maintain outstanding the same subjects successively renewed, enabling the resistance of popular narrative tradition and understanding and appreciation of popular orality (ZUMTHOR, 1993; 2000) and of the updates performed in the contemporarity (CANDIDO, 1976), without losing sight of the singularity and autonomy of the literary work

Inferências carioevolutivas sobre grupos crípticos de peixes marinhos e estuarinos

Cytogenetic studies have been revealing a great diversity not detected, until then, in several families of fishes. Many of these groups, especially those that exhibit great diversity, like Perciformes and Siluriformes, possess species with difficult morphologic characterization, called cryptic species, commonly detected through karyotypic analyses, which reveals outstanding interespecific variations with relationship to the number and its chromosomal structures. Thus, the present work intends to contribute for the cytogenetic knowledge of marine and brackish fish species, because they peculiar life habits and by lack of cytogenetic data of your genetic aspects. Therefore, cytogenetic studies were developed in a species of Apogonidae (Perciformes), two species of sea catfishes of the family Ariidae (Siluriformes) and brackish fish Paurachenipterus galeatus (Siluriformes, Auchenipteridae), through C banding, Ag-NOR, use of base-specific flourochromes (DAPI and CMA3), as well as FISH (Fluorescent in situ hybridization) using ribosomal DNA probes 5S and 18S. The present results contribute to a better understanding of the processes of differentiation patterns and chromosome evolution in these groups. The use of other approaches (the morphology and molecular tools) will allow a larger understanding of the genetic and biological diversity of the Brazilian ichthyofauna.

Levantamento cariotípico em espécies de peixes marinhos costeiros de fundo arenoso (Osteichthypes, Perciformes)

Cytogenetics analyses in fish are important because they compose a private group among the vertebrates, occupying a central position in the animal evolution. The Perciforms Order, dominant in the marine and freshwater environment, it constitutes a model potentially useful in the genetic evaluation of populations, as well as in the understanding of its evolutionary processes. In spite of this, cytogenetics studies in this great group is scarce, above all for the inhabitants of sandy bottom and pelagics habits. The present work proposed to contribute for the cytogenetic characterization of nine species of fish marine of sandy bottom of the coast of Rio Grande do Norte (Brazil), identifying the evolutionary patterns related to the karyotype in these species and the existence of filogenetics affinities between them and other Perciformes. The animals were collected in the beaches of the Redinha, Ponta Negra and Búzios (Coast of Rio Grande do Norte) and in Saint Peter and Saint Paul Archipelago. Later on they were submitted to the cytogenetics technical that consist of mitotic estimulation, obtaining of mitotics chromosomes, proceeded by techniques of conventional coloration (Giemsa) and chromosomic bands (Ag-RONs and C band). Diploid number and fundamental number equal to 48 were observed in most of the species: Menticirrhus americanus, Ophioscion punctatissimus, Pareques acuminatus (Sciaenidae); Chloroscombrus chrysurus (Carangidae); Echeneis sp. 2 (Echeneidae); Archosargus probatocephalus (Sparidae) and Orthopristis ruber (Haemulidae). Trachinotus goodei (NF=52) (Carangidae) and Echeneis sp. 1 (Echeneidae) (NF=54) presented variation in NF, staying constant a diploid number equal to 48. RONs was situated in pericentromeric position in whole the scianids, and in the species Echeneis sp. 2 (22° pair), O. ruber and A. probatocephalus (1° pair), coinciding with great heterocromatics blocks in M. americanus (1° pair), P. acuminatus (2° pairl) and O. ruber (1° pair). RONs was also located in the telomeric area of the short arm of the 5° and 11° acrocentrics pairs in T. goodei, 4° and 19° pairs of C. chrysurus, 1° pair (sm) of Echeneis sp. 1. The C band detected centromeric blocks in most of the chromosomes of the species of Sciaenidae, Carangidae and Echeneidae, with great blocks in A. probatocephalus (4° pair). Heterocromatic blocks in telomeric areas in submetacentrics of Echeneis sp. 1, and pericentromerics in M. americanus (1° and 8° pairs), O. punctatissimus (1° pair) and P. acuminatus (2° pair) were also observed. It is noticed a marked conservatism cromossomic in the species of the family Scianidae and Haemulidae in what says respect to the number of acrocentrics chromosomes and the location of RONs. Even so it is outstanding the presence of heterocromatinization events during the karyotypic evolution of this family. Already in the families Sparidae and Carangidae, the obtained results reaffirm examples of small variations structural resultants of inversion and translocation Robertsonian, as important mechanisms of diversification karyotipical, as well as a pattern numerical evolutionary conserved, also observed in representatives of Echeneidae of Atlantic in relation to Pacific. The presence of RONs multiple, observed in the species T. goodei and C. chrysurus seems to represent a character derived in the family Carangidae. The results for the species O. ruber and A. probatocephalus suggest the presence of possible geographical or climatic barriers among populations of NE of Brazil in relationship the one of the SE

O papel das relações sociais e da atenção social durante tarefas cooperativas em Callithrix jacchus

Several studies on nonhuman primates show that the relationships between individuals strongly influence the expression of cooperative behavior, both in natural environment and in captivity settings. Recent studies suggest that cooperative breeders present outstanding performance in tasks involving social cognition, such as cooperative tasks with experimental apparatuses. In experimental research on this subject it is crucial to differentiate between real cooperation (or communicative cooperation, mediated by social attention) and by-product cooperation that results from simultaneous actions of individuals. The present study assessed, in Callithrix jacchus, a cooperative breeder species, if social relationships and social attention between subjects are important factors during performance in cooperative tasks. During the experimental procedure the animals participated in three different cooperative tasks: cooperation task, prosocial task and control task. Diverging from the literature, matrix correlation tests revealed no significant relationship between grooming or proximity and the execution of the tasks, suggesting that other factors such as age or hierarchy may have an effect on the performance in cooperative tasks in this species. There was also no relationship between the execution of the cooperative tasks and social glances, suggesting that there was no social attention during the tasks. Moreover, there were lower rates of social glances in the cooperative tasks as opposed to the control tasks. However, the small number of pulls in prosocial tasks suggests that the animals distinguished between tasks that benefited only a partner and tasks that generated benefits to themselves, choosing the latter. We conclude that, for the tasks presented in this study, we could neither detect the role of social relationships on the cooperative tasks nor assert that there were true cooperation and prosocial behavior

Avaliação das características de afetividade em crianças e jovens com síndrome de down

This work presents the processes and the results of a research concerning the affectivity in children suffering from the Down´s Syndrome (DS). The relevance of the study is justified due to the need of the development of researches, in the area of psychological evaluation of people who suffers from Down´s Syndrome (DS), that are backed by the use of appropriate instruments for such purpose. The thematic discussed focuses the characteristics of the affectivity of children suffering from Down´s Syndrome. Affectivity, conceptually, is considered a wide phenomenon, including several aspects such as emotions, passions, anxiety, anguish, sadness, happiness and even the pleasure sensations and pain. The general objective of the study consisted of investigating the manifestation of the affectivity in children and young with Down´s Syndrome and the parents´ and educators´ perception concerning the expression of the affectivity in the behavior and in the social activities. The specific objectives were: to identify the parents' perceptions about the several manifestations of indicative behaviors of affectivity; to verify in the social atmosphere, outside home, through the teachers' perception, the several forms and intensities of the expression of the affectivity; and, to make possible the use of the technique of Zulliger (Z-test) in people with Down´s Syndrome. 70 (seventy) children and young with Down´s Syndrome participated in the research, in the age group from 04 to 26 years old, which are attended by Institutions of Paraíba and of Rio Grande do Norte. The instruments used were two questionnaires, applied with the parents and teachers, and the projective technique, Z-test, applied, individually, with the children and young with Down´s Syndrome. For analysis of the data of the questionnaires, the program Trideux-Mots was used, with the intention of selecting the main outstanding words for the parents and teachers concerning the expression of the children's affectivity and young with Down´s Syndrome. For so much, it was organized a database that was processed by that program and, soon after, interpreted through the Factorial Analysis by Correspondence (AFC), looking for to clear the modalities of presented answers in an organized way, through a graph. The data of the Z-test were analyzed, taking in consideration the need to characterize the aspects of the affectivity and the elaboration of specific norms for this sample type, through normalized scores. In agreement with the data presented by Tri-deux-Mots, it was observed that in the affective behavior and in the relationship with the other, home and in the school, the children and young with Down´s Syndrome they express your affectivity through positive and negative characteristics, in the same way that any other child that doesn't have to syndrome. The Z-test made possible initial elements to work with that population, however it is necessary that grow other researches with the intention of investigating the reason of the answers they present not the specific categories that you/they are related to the affectivity, since it was well-known the diversity of affective characteristics presented by the researched group

Suporte ao uso de álcool e drogas na atenção primária: um estudo com equipes de Natal/RN

National surveys indicate that 6.8 % of the brazilian population is dependent on alcohol and 1 % dependent on illicit drugs, representing a significant portion of the population affected by this issue . Primary Care becomes instrumental in expanding the coverage of this demand and in reducing unnecessary referrals for specialized care. This study aimed to investigate the responsiveness and institutional support of Primary Care Teams in relation to the demands of alcohol and drugs users. The research was conducted in a Family Health Unit in West Sanitary District of Natal City. With quantitative and qualitative nature, our study consisted of two stages. At first, we performed a mapping of alcohol and other drugs abusive use in a sample of the population assisted by Family Heath Teams, using sociodemographic questionnaire and ASSIST (Alcohol, Smoking and Substance Involvement Screening Test). 406 questionnaires were completed. Of these questionnaires, 27.8% are men and 72.2% women, of which 56% are between 20 and 39 years-old, they are housewives, have a stable relationship and are consumers of tobacco (37.6%), marijuana (13%) and especially alcohol (57%). In second stage, two Conversation Circles with Family Health Teams and the referential Family Health Support Center were formed to discuss the data of the mapping realized in the previous phase. The circles, which had participation of 20 of the 37 professional teams from Family Health and 2 from Family Health Support Center, showed a lack of professional training in the subject; inability of the healthcare network in the user embracement; belief of professionals that nothing can be done when matter is alcohol and drugs; and referencing as the only care action performed by teams. Thus we point out the need to support an approach on issues of alcohol and drugs which consider gender issues, investing in Harm Reduction Policy as a possibility of working in this context for recognizing each user in their uniqueness and strategizing with them to promote health in a broad and contextualized way

Adolescentes preocupadas em conquistar um corpo magro: Um estudo sobre discursos produzidos em diários eletrônicos

The concern about a good physical condition is heavily present nowadays, in documentary films about health and in the media, and it is also expressed through the outstanding growth of physical academies, beauty institutes and aesthetic medicine and all kind of aesthetic surgeries. In the western world the body wave is a significant trend, characterized by the great investments in body image. However, what is overlooked is the fact that in parallel trend grows the number of teenagers, especially females, with all kind of problems related to their body image. As adolescence is a moment of transformations, teenagers tend to be more aware of their body image and often neglect food ingestion and try to build their bodies following the images they have from top models and movie stars. The low self-esteem accompanying this sort of experience is an additional problem. Therefore the research aim to analyze discourses regarding the body image produced in world wide web diaries (blogs). The blogs selection was made through the site www.blogs.com.br, which is considered the widest guide of electronic diaries in Brazil. We looked after blogs including the keyword body and from adolescents aged 10 to 19, who showed concern about a slim body. Three blogs were chosen, considering the example criteria. Discourse analysis shows that these teenagers feel unsatisfied with their bodies, searching by all means the thinness presented as a aesthetic paradigm in western societies which often implies neglecting their own health, using appetite inhibitor drugs, restricting or totally abstaining food ingestion for long periods of time, or provoking themselves vomits after ingesting food. These behaviors, together with intense fear of gaining weight, can be characterized as alimentary disorders, related to the body image. As they usually hide this sort of behaviors from family and friends who do not share this concern, the blogs seem to be an easy tool for adolescents to find peers with whom to share common values and ideas and reaffirm their identities and virtual sense of community

O dispositivo alta nos Centros de Atenção Psicossocial/CAPS : loucura, vida cotidiana e organização social

The present paper proposes an analysis about the Brazilian Psychiatric Reform as a public policy and deriving from a research developed with the workers of a Psychosocial Attention Centre III (CAPS III) and the managers of the Psychosocial Attention Web (REAP) in Aracaju. This analysis is developed as an investigation of the discharge at those services, understood not as a procedure, but as a dispositive from which different elements can be articulated: users, knowledge, technical procedures, police measures, juridical decisions, laws, services edifying. This, form the background of the articulation between mental alienation and the subject of right alienation, in the ways through which this articulation develops to the relations between madness,citizenship, internment and substitutive practices. Our investigation about the discharge as a dispositive was built with some narrative constructions, as a discourse analysis inspired by Michel Foucault s method, from the perspective of some of the main dispositive operators: workers and managers. The main aspect observed were: the articulations built by the discharge as a dispositive based on two discursive grate, the Reform as a new treatment substituting internship, and the Reform as juridical insertion and users rights practice; the exercise of these discursive grades based on the workers and managers perspective; the transference of limitations and contradictions of these grades to the competence of the dispositive operators, emerged in an outstanding way, as sometimes those operators are liable for the emergent limitations and difficulties, and some other times they are restrained by their institutional role, which is to maintain the domination relations articulated by the dispositive; finally, some aspects extracted which the dispositive operators - when they were expected to act in a way to maintain certain power relations - were capable to resist, managing other power relations from the dispositive, that we call, as Agamben, dispositive profanity

Aplicação de sabões de ácidos graxos epoxidados como inibidores de corrosão em oleoduto

Corrosion usually occurs in pipelines, so that it is necessary to develop new surface treatments to control it. Surfactants have played an outstanding role in this field due to its capacity of adsorbing on metal surfaces, resulting in interfaces with structures that protect the metal at low surfactant concentrations. The appearance of new surfactants is a contribution to the area, as they increase the possibility of corrosion control at specific conditions that a particular oil field presents. The aim of this work is to synthesize the surfactants sodium 12 hydroxyocadecenoate (SAR), sodium 9,10-epoxy-12 hydroxyocadecanoate (SEAR), and sodium 9,10:12,13-diepoxy-octadecanoate (SEAL) and apply them as corrosion inhibitors, studying their action in environments with different salinities and at different temperatures. The conditions used in this work were chosen in order to reproduce oil field reality. The study of the micellization of these surfactants in the liquid-gas interface was carried out using surface tensiometry. It was observed that cmc increased as salt concentration was increased, and temperature and pH were decreased, while cmc decreased with the addition of two epoxy groups in the molecule. Using the values of cmc and the Gibbs equation, the values of Gibbs free energy of adsorption, area per adsorbed molecule, and surface excess were calculated. The surface excess increases as salt concentration and temperature decreases, increasing as pH is increased. The area per adsorbed molecule and the free energy of adsorption decrease with salt concentration, temperature, and pH increase. SAXS results showed that the addition of epoxy group in surfactant structure results in a decrease in the repulsion between the micelles, favoring the formation of more oblong micellar structures, ensuring a better efficiency of metal coverage. The increase in salt and surfactant concentrations provides an increase in micellar diameter. It was shown that the increase in temperature does not influence micellar structure, indicating thermal stability that is advantageous for use as corrosion inhibitor. The results of inhibition efficiency for the surfactants SEAR and SEAL were considered the best ones. Above cmc, adsorption occurred by the migration of micelles from the bulk of the solution to the metal surface, while at concentrations below cmc film formation must be due to the adsorption of semi-micellar and monomeric structures, certainly due to the presence of the epoxy group, which allows side interactions of the molecule with the metal surface. The metal resistance to corrosion presented values of 90% of efficiency. The application of Langmuir and Frumkin isotherms showed that the later gives a better description of adsorption because the model takes into account side interactions from the adsorbing molecules. Wettability results showed that micelle formation on the solid surface occurs at concentrations in the magnitude of 10-3 M, which isthe value found in the cmc study. This value also justifies the maximum efficiencies obtained for the measurements of corrosion resistance at this concentration. The values of contact angle as a function of time suggest that adsorption increases with time, due to the formation of micellar structures on metal surface

Potencial de uso dos recursos vegetais em uma comunidade rural do semiárido do Rio Grande do Norte

The aim of the present study was to identify the main plant use categories of native varieties from the Caatinga biome, in the rural community of Caicó, Rio Grande do Norte state (Northeastern Brazil). Semi-structured and structured interviews were used to gather information from local specialists about the use of the plants. The uses of 69 species are described by 23 observers (woodsmen, herb doctors, healers, farmers and housewives) aged 35 years or more. These species were allocated to seven categories: medicinal, wood plants, nutritional, mystic, fuel, forage plants and domestic use. The most represented families were Fabaceae (14 spp.), Euphorbiaceae (6 spp.), Cucurbitaceae (3 spp.) and Cactaceae (3 spp.). The calculation of use- value showed that the cumaru (Amburana cearensis (Allemão) A. C. Sm) and the jurema-preta (Mimosa tenuiflora (Willd.) Poir) were the most commonly mentioned, in addition to having the largest number of uses. The data obtained confirm the potential of the plants from the Seridó region and reinforce the importance of biodiversity for rural communities, underscoring the need for local plant management

Caracterização tectono-estratigráfica da sequência transicional na sub-bacia de Sergipe

This thesis deals with the tectonic-stratigraphic evolution of the Transitional Sequence in the Sergipe Sub-basin (the southern segment of the Sergipe-Alagoas Basin, Northeast Brazil), deposited in the time interval of the upper Alagoas/Aptian stage. Sequence boundaries and higher order internal sequences were identified, as well as the structures that affect or control its deposition. This integrated approach aimed to characterize the geodynamic setting and processes active during deposition of the Transitional Sequence, and its relations with the evolutionary tectonic stages recognized in the East Brazilian Margin basins. This subject addresses more general questions discussed in the literature, regarding the evolution from the Rift to the Drift stages, the expression and significance of the breakup unconformity, the relationships between sedimentation and tectonics at extensional settings, as well as the control on subsidence processes during this time interval. The tectonic-stratigraphic analysis of the Transitional Sequence was based on seismic sections and well logs, distributed along the Sergipe Sub-basin (SBSE). Geoseismic sections and seismic facies analysis, stratigraphic profiles and sections, were compiled through the main structural blocks of this sub-basin. These products support the depositional and tectonic-stratigraphic evolutionary models built for this sequence. The structural analysis highlighted similarities in deformation styles and kinematics during deposition of the Rift and Transitional sequences, pointing to continuing lithospheric extensional processes along a NW trend (X strain axis) until the end of deposition of the latter sequence was finished by the end of late Aptian. The late stage of extension/rifting was marked by (i) continuous (or as pulses) fault activity along the basin, controling subsidence and creation of depositional space, thereby characterizing upper crustal thinning and (ii) sagstyle deposition of the Transitional Sequence at a larger scale, reflecting the ductile stretching and thinnning of lower and sub crustal layers combined with an increasing importance of the thermal subsidence regime. Besides the late increments of rift tectonics, the Transitional Sequence is also affected by reactivation of the border faults of SBSE, during and after deposition of the Riachuelo Formation (lower section of the Transgressive Marine Sequence, of Albian age). It is possible that this reactivation reflects (through stress propagation along the newlycreated continental margin) the rifting processes still active further north, between the Alagoas Sub-basin and the Pernambuco-Paraíba Basin. The evaporitic beds of the Transitional Sequence contributed to the development of post-rift structures related to halokinesis and the continental margin collapse, affecting strata of the overlying marine sequences during the Middle Albian to the Maastrichtian, or even the Paleogene time interval. The stratigraphic analysis evidenced 5 depositional sequences of higher order, whose vertical succession indicates an upward increase of the base level, marked by deposition of continental siliciclastic systems overlain by lagunar-evaporitic and restricted marine systems, indicating that the Transitional Sequence was deposited during relative increase of the eustatic sea level. At a 2nd order cycle, the Transitional Sequence may represent the initial deposition of a Transgressive Systems Tract, whose passage to a Marine Transgressive Sequence would also be marked by the drowning of the depositional systems. At a 3rd order cycle, the sequence boundary corresponds to a local unconformity that laterally grades to a widespread correlative conformity. This boundary surface corresponds to a breakup unconformity , being equivalent to the Pre-Albian Unconformity at the SBSE and contrasting with the outstanding Pre-upper Alagoas Unconformity at the base of the Transitional Sequence; the latter is alternatively referred, in the literature, as the breakup unconformity. This Thesis supports the Pre-Albian Unconformity as marker of a major change in the (Rift-Drift) depositional and tectonic setting at SBSE, with equivalent but also diachronous boundary surfaces in other basins of the Atlantic margin. The Pre-upper Alagoas Unconformity developed due to astenosphere uplift (heating under high lithospheric extension rates) and post-dates the last major fault pulse and subsequent extensive block erosion. Later on, the number and net slip of active faults significantly decrease. At deep to ultra deep water basin segments, seaward-dipping reflectors (SDRs) are unconformably overlain by the seismic horizons correlated to the Transitional Sequence. The SDRs volcanic rocks overly (at least in part) continental crust and are tentatively ascribed to melting by adiabatic decompression of the rising astenospheric mantle. Even though being a major feature of SBSE (and possibly of other basins), the Pre-upper Alagoas Unconformity do not correspond to the end of lithospheric extension processes and beginning of seafloor spreading, as shown by the crustal-scale extensional structures that post-date the Transitional Sequence. Based on this whole context, deposition of the Transitional Sequence is better placed at a late interval of the Rift Stage, with the advance of an epicontinental sea over a crustal segment still undergoing extension. Along this segment, sedimentation was controled by a combination of thermal and mechanical subsidence. In continuation, the creation of oceanic lithosphere led to a decline in the mechanical subsidence component, extension was transferred to the mesoceanic ridge and the newly-formed continental margin (and the corresponding Marine Sequence) began to be controlled exclusively by the thermal subsidence component. Classical concepts, multidisciplinary data and new architectural and evolutionary crustal models can be reconciled and better understood under these lines

Evolução geodinâmica e condicionamento estrutural dos terrenos Piancó-Alto Brígida e Alto Pajeú, domínio da zona transversal, NE do Brasil

This thesis aims to advance in the geological knowledge of the region comprising the Piancó-Alto Brígida (TPAB) and Alto pajeú (TAP) terranes, in the Transversal Zone Domain (Borborema Province, NE Brazil), with the main objective of understanding the geodynamic evolution and the structural framework of these units. To reach this objective, and besides field work and interpretation of traditional aerial photographs, other tools were employed like of remote sensing products (Landsat 7 ETM+, aeroradiometrics, aeromagnetics and topographical images), lithogeochemical (whole rock) analyses and geochronological dating (U-Pb in zircon), besides integration with literature data. In the area, several precambrian geological units outcrop, represented in the TAP by the paleoproterozoic Serra Talhada and Afogados da Ingazeira complexes, Riacho Gravatá Complex (metavolcano-sedimentary sequence of Stenian-Tonian age) and Cariris Velhos orthogneisses (of Tonian age). The TPAB comprises the Santana do Garrote (lower unit) and Serra do Olho d'Água (upper unit) formations of the Cachoeirinha Group (Neoproterozoic III), besides the Piancó orthogneisses and Bom Jesus paragneisses; the latter correspond to an older (basement ?) block and a possible high grade equivalent of the Cachoeirinha Group (or Seridó Group ?), respectively. Several Brasiliano-age plutons occur in both terranes.The aeromagnetic data show the continuity, at depth, of the main shear zones mapped in the region. The Patos, Pernambuco, Boqueirão dos Cochos, Serra do Caboclo, Afogados da Ingazeira/Jabitacá and Congo-Cruzeiro do Nordeste shear zones reach depths greater than to 6-16 km. The aeromagnetic signature of other shear zones, like the Juru one, suggests that these structures correspond to shallower crustal features. The satellite images (Landsat 7 ETM+) and aerogamaspectrometric images discriminate different geological units, contributing to the mapping of the structural framework of the region. The Serra do Caboclo Shear Zone was characterized as the boundary/suture between the TPAB and TAP. This structure is an outstanding, pervasive feature that separates contrasting geological units, such as the Neoproterozoic III Cachoeirinha Group in the TPAB and the Riacho Gravatá Complex and the Cariris Velhos metaplutonics, of Stenian-Tonian age, in the TAP. Occupying different blocks, these units are not found in authoctonous relations, like unconformities and intrusive contacts. Concerning the Cariris Velhos (ca. 1,0 Ga old) event is recorded by radiometric ages of the Riacho Gravatá Complex metavolcanics and intrusive augen and orthogneisses, all of them displaying geochemical affinities of arc or collisional settings. A structural signature of this event was not recorded in the region, possibly due to its low grade/low strain style, obliterated by the overprinting of younger, higher grade/high strain Brasiliano-age fabrics.The first tectonic event (D1) observed in the Cariris Velhos lithotypes presents contractional kinematics with transport to the NW. Neoproterozoic III geochronologic dates, obtained in late-D1 granitoids, imply a Brasiliano age (ca. 610-600 Ma) for this deformation event. The second tectonic event (D2) characterized in the region corresponds to the Brasiliano transcurrent kinematics of the outstanding shear zones and associated granitoid plutons. The geochronological (U-Pb in zircon) data obtained during this thesis also confirms the occurrence of the Cariris Velhos magmatic suite in the TAP, as well as the Neoproterozoic III age to the Cachoeirinha Group in the TPAB. The TAP (Riacho Gravatá Complex, augen and orthogneisses) is interpreted as a continental arc possibly accreted to a microcontinent during the Cariris Velhos (Stenian-Tonian) event. Later on, this terrane collided with the TPAB at the beginning of the Brasiliano orogeny (D1 contractional deformation), and both domins were reworked by the transcurrent shear deformation of the D2 event

Litoestratigrafia e deformação cenzóica na região de Icapuí, Ceará, e implicações para a estruturação de campos de petróleo na borda ocidental da bacia Potiguar(NE do Brasil)

This thesis deals with the sedimentological/stratigraphic and structural evolution of the sedimentary rocks that occur in the NW continental border of the Potiguar Basin. These rocks are well exposed along coastal cliffs between the localities of Lagoa do Mato and Icapuí, Ceará State (NE Brazil). The sedimentological/stratigraphic study involved, at the outcrop scale, detailed facies descriptions, profile mapping of the vertical succession of different beds, and columnar sections displaying inferred lateral relationships. The approach was complemented by granulometric and petrographic analyses, including the characterization of heavy mineral assemblages. The data set allowed to recognize two kinds of lithological units, a carbonate one of very restricted occurrence at the base of the cliffs, and three younger, distinct siliciclastic units, that predominate along the cliffs, in vertical and lateral extent. The carbonate rocks were correlated to the late Cretaceous Jandaíra Formation, which is covered by the siliciclastic Barreiras Formation. The Barreiras Formation occurs in two distinct structural settings, the usual one with nondeformed, subhorizontal strata, or as tilted beds, affected by strong deformation. Two lithofacies were recognized, vertically arranged or in fault contacts. The lower facies is characterized by silty-argillaceous sandstones with low-angle cross bedding; the upper facies comprises medium to coarse grained sandstones, with conglomeratic layers. The Tibau Formation (medium to coarse-grained sandstones with argillite intercalations) occurs at the NW side of the studied area, laterally interlayered with the Barreiras Formation. Eolic sediments correlated to the Potengi Formation overly the former units, either displaying an angular unconformity, or simply an erosional contact (stratigraphic unconformity). Outstanding structural features, identified in the Barreiras Formation, led to characterize a neocenozoic stress field, which generated faults and folds and/or reactivated older structures in the subjacent late cretaceous (to paleogene, in the offshore basin) section. The structures recognized in the Barreiras Formation comprise two distinct assemblages, namely a main extensional deformation between the localities of Ponta Grossa and Redonda, and a contractional style (succeeded by oblique extensional structures) at Vila Nova. In the first case, the structural assemblage is dominated by N-S (N±20°Az) steep to gently-dipping extensional faults, displaying a domino-style or listric geometry with associated roll-over structures. This deformation pattern is explained by an E-W/WNW extension, contemporaneous with deposition of the upper facies of the Barreiras Formation, during the time interval Miocene to Pleistocene. Strong rotation of blocks and faults generated low-angle distensional faults and, locally, subvertical bedding, allowing to estimate very high strain states, with extension estimates varying between 40% up to 200%. Numerous detachment zones, parallel to bedding, help to acommodate this intense deformation. The detachment surfaces and a large number of faults display mesoscopic features analoguous to the ones of ductile shear zones, with development of S-C fabrics, shear bands, sigmoidal clasts and others, pointing to a hydroplastic deformation regime in these cases. Local occurrences of the Jandaíra limestone are controled by extensional faults that exhume the pre-Barreiras section, including an earlier event with N-S extension. Finally, WNWtrending extensional shear zones and faults are compatible with the Holocene stress field along the present continental margin. In the Vila Nova region, close to Icapuí, gentle normal folds with fold hinges shallowly pluging to SSW affect the lower facies of the Barreiras Formation, displaying an incipient dissolution cleavage associated with an extension lineation at high rake (a S>L fabric). Deposition of the upper facies siliciclastics is controlled by pull-apart graben structures, bordered by N-NE-trending sinistral-normal shear zones and faults, characterizing an structural inversion. Microstructures are compatible with tectonic deformation of the sedimentary pile, burried at shallow depths. The observed features point to high pore fluid pressures during deformation of the sediments, producing hydroplastic structures through mechanisms of granular flow. Such structures are overprinted by microfractures and microfaults (an essentially brittle regime), tracking the change to microfracturing and frictional shear mechanisms accompanying progressive dewatering and sediment lithification. Correlation of the structures observed at the surface with those present at depth was tested through geophysical data (Ground Penetrating Radar, seismics and a magnetic map). EW and NE-trending lineaments are observed in the magnetic map. The seismic sections display several examples of positive flower structures which affect the base of the cretaceous sediments; at higher stratigraphic levels, normal components/slips are compatible with the negative structural inversion characterized at the surface. Such correlations assisted in proposing a structural model compatible with the regional tectonic framework. The strong neogenepleistocene deformation is necessarily propagated in the subsurface, affecting the late cretaceous section (Açu and Jandaíra formations), wich host the hydrocarbon reservoirs in this portion of the Potiguar Basin. The proposed structural model is related to the dextral transcurrent/transform deformation along the Equatorial Margin, associated with transpressive terminations of E-W fault zones, or at their intersections with NE-trending lineaments, such as the Ponta Grossa-Fazenda Belém one (the LPGFB, itself controlled by a Brasiliano-age strike-slip shear zone). In a first step (and possibly during the late Cretaceous to Paleogene), this lineament was activated under a sinistral transpressional regime (antithetic to the main dextral deformation in the E-W zones), giving way to the folds in the lower facies of the Barreiras Formation, as well as the positive flower structures mapped through the seismic sections, at depth. This stage was succeeded (or was penecontemporaneous) by the extensional structures related to a (also sinistral) transtensional movement stage, associated to volcanism (Macau, Messejana) and thermal doming processes during the Neogene-Pleistocene time interval. This structural model has direct implications to hydrocarbon exploration and exploitation activities at this sector of the Potiguar Basin and its offshore continuation. The structure of the reservoirs at depth (Açu Formation sandstones of the post-rift section) may be controlled (or at least, strongly influenced) by the deformation geometry and kinematics characterized at the surface. In addition, the deformation event recognized in the Barreiras Formation has an age close to the one postulated for the oil maturation and migration in the basin, between the Oligocene to the Miocene. In this way, the described structural cenario represents a valid model to understand the conditions of hydrocarbon transport and acummulation through space openings, trap formation and destruction. This model is potentially applicable to the NW region of the Potiguar Basin and other sectors with a similar structural setting, along the brazilian Equatorial Atlantic Margin