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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Magnetisation transfer contrast as a quantitative MRI technique for the study of bio-polymer systems

Pidwell, Anna Louise January 2001 (has links)
No description available.
12

The singer's psyche : a psychological approach to vocal performance training

Borland, Denise January 2011 (has links)
No description available.
13

Portfolio of composition with accompanying commentary

Goves, Lawrence January 2010 (has links)
This is the written commentary on a practice-based period of research. This research has focussed on the development of a substantial series of new musical compositions considering the development of unique and personal identity in composition. As well as broader technical consideration the commentary emphasises the incorporation of new technology and electronic media into composition, collaborations with other creative artists and performers and in developing vocal music with Matthew Welton, a literary collaborator. The commentary prioritises three main compositions; the terminus wreck for cello and electronics; My name is Peter Stillman. That is not my real name. for piano and electric piano and; Things that are blue, things that are white and things that are black. for piano, electric piano, prepared piano with clarinet/bass clarinet, cor anglais, horn, viola, cello and at least 16 violins. These are all substantial pieces between 15 and 30 minutes in duration for a variety of forces and, particularly between the two piano works, demonstrate a clear trajectory of development. Chapters are also dedicated to smaller-scale chamber works, vocal music, collaboration and the house of bedlam, a new ensemble formed as an element of the research.
14

Jean Sibelius : progressive techniques in the symphonies and tone-poems

Howell, Timothy B. January 1985 (has links)
As an analytical and critical survey of Sibelius' symphonies and tone-poems, this study is designed to fill a significant gap in the research of this composer which hitherto has been primarily concerned with historical and musicological issues. Those analytical investigations which exist, typically as a supplement to more biographical concerns, have not made use of modern techniques nor are they comprehensive. Beyond this self-evident purpose of processing analytical findings, the thesis aims not only to demonstrate a symposium of Sibelius' compositional techniques but also to give a new perspective to these achievements. The layout and presentation of material has been designed to facilitate this dual purpose, dispensing with a mere catalogue of analyses in favour of grouping their findings into considerations of larger issues. Thus, Part I - 'The Symphonies' - reflects the layered analytical approach to each work in chapters which move from the general to the particular (Style, Form, Tonality, Thematic Process) selecting examples from the entire genre appropriate to each issue. The final chapter in this section concludes by synthesising those areas in a detailed analysis of a single work. Part II - 'The Tone-Poems' - opens with a more general discussion of the two genres in question revealing cChtrasts and consistencies. Thereafter, their survey divides into two apparently chronological sections, though in fact the distinction is a stylistic one and complements internal considerations of the symphonies themselves. The application of reductive, layered analysis appears to be new in this context and its findings reveal a more progressive compositional attitude than has previously been credited to a figure generally viewed as reactionary. Its evidence, notably in the areas of extended tonality and formal compression, suggests an historical placing for Sibelius within twentieth-century musical developments, indicating both his awareness of the problems facing composers of the period and his personal solutions. The final chapter discusses this essentially speculative topic, its more subjective standpoint balancing the analytical objectivity which constitutes the majority of the thesis. Its conclusion is modest: Sibelius as neither reactionary nor revolutionary, but, nevertheless, progressive.
15

Portfolio of compositions with accompanying commentary

Elia, Marios Joannou January 2010 (has links)
The commentary focuses on the predominantly applied extraneous media in my music, that is, the inclusion of literary sources. The discourse begins with a biographical sketch (Chapter 1), followed by a succinct description of the concept of polymediality, which involves two dimensions: the work-immanent compositional and polymediality on the process of staging (Chapter 2). Chapter 3 considers literary sources as a constituent component of music's polymediality. The first part is preoccupied with the implementation of textual elements and vocality in instrumental works, with special reference to the orchestral piece AKANTHAI. Simultaneously, this section elucidates a series of fundamental architectural tools and aspects of the music, encompassing (a) the methodological advancement concerning analogous relationships, (b) the processing of linear transitions and polyphonic settings depending on the model of imitative interaction, (c) the polydimensional articulation of homogeneity, (d) the aspect of permanent fleetingness, (e) the different facets of hybridization and their implications, (f) the question of the musico-literary intermediality form, and (g) the concept of polyaesthetics. To this extent, the commentary reports on a research aiming at elaborating the hypothesis that musical and non-musical elements, like the literary sources, are mustered from a diversified spectrum of coherent principles. Turning to the example of the opera entitled DIE JAGD, the second part of Chapter 3 is concerned with the situative conditions resulting from the abrupt omission of the relationship to the libretto, whereby the focus is displaced 'outside' the textual frame of reference. Chapter 4 briefly highlights the scope of three further text-related parameters of the music in conjunction with their aesthetic issues: the specified titles of the works, the delineated expressive nuances, as well as the descriptive commentaries and textual depictions found on the score. Furthermore, the chapter outlines the consequences of two-dimensional theatricality and meta-theatricality. In conclusion, the commentary argues that the compositional procedure adopts literary references for the benefit of creating self-generated concepts. In other words, constituted within a plethora of musical and extra-musical elements, texts function as energetic catalytic stimuli; they become the key mechanism to enhance interactive system performance amidst the music's structural-strategic and conceptual framework.
16

Composition portfolio & written commentary

Ilzetzki, Ophir N. January 2012 (has links)
Interpreting a scored musical composition entails the composer’s relinquishing some control over the piece to the performer. In ‘open’ scores the composer relinquishes most control and in effect allows the performer to collaborate in the compositional process; in traditional scores the composer specifies as much as possible in order to leave little to no room for the performer to use personal judgment regarding interpretation. The principal focus of this portfolio will be to examine, through different scores and compositional techniques, a possible available spectrum between these two types of scores and to define more clearly different options presenting varying degrees of control over a score. The initial stimulus for this research stems from a fascination with alternative compositional scenarios that consequentially aid the creation of incidental musical materials that are not specified or scored. These moments resemble an improvisation in their immediacy of execution and erratic sound characteristics. Hence, it is this quality that many of the ‘open’ elements in these portfolio pieces try to extract, but not exclusively so. The thesis will also dwell on elements of performance psychology in attempts to better define the mechanisms at work in different interpretation/improvisation scenarios, as well as refer to non-classical musical traditions as an example of alternative didactic systems leading towards a non-score based, quasiimprovisational practice. Finally, each portfolio composition will be described in detail with a particular emphasis on its erratic sound-qualities, its ‘open’ element, or both.
17

Flora e estrutura do estrato arbóreo e relações solo-vegetação de cerradão em Barão de Melgaço, pantanal de Mato Grosso, Brasil / Flora and structure of the tree component and soil-vegetation relations of woodland savanna in Barão de Melgaço, pantanal of Mato Grosso, Brazil

Lima Júnior, Gilmar Alves 02 April 2007 (has links)
Submitted by Marco Antônio de Ramos Chagas (mchagas@ufv.br) on 2016-05-18T15:33:59Z No. of bitstreams: 1 texto completo.pdf: 3393291 bytes, checksum: 70d4732d9ffad3915c30bf8008c5e963 (MD5) / Made available in DSpace on 2016-05-18T15:33:59Z (GMT). No. of bitstreams: 1 texto completo.pdf: 3393291 bytes, checksum: 70d4732d9ffad3915c30bf8008c5e963 (MD5) Previous issue date: 2007-04-02 / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior / O objetivo deste estudo foi analisar a relação vegetação-solo da flora arbórea de duas áreas de cerradão no Pantanal Norte, localizadas na RPPN SESC Pantanal, Barão de Melgaço, MT (16°37’S e 56°15’W). Foram demarcadas cinco parcelas de 20 x 50 m em cada área, divididas em subparcelas de 10 m 2 . Amostraram-se todos os indivíduos arbóreos com DAS = 4,7 cm. Foram calculados os parâmetros fitossociológicos, riqueza de espécies e diversidade. Para a análise do solo foram coletadas amostras compostas do horizonte superficial do solo (0-20 cm). O levantamento apresentou um total de 72 espécies, distribuídas em 56 gêneros e 28 famílias botânicas, sendo que nove e 30 espécies foram exclusivas da área I e II, respectivamente. As famílias Fabaceae, Malvaceae e Bignoniaceae se destacaram em número de espécies. O gênero Tabebuia foi o mais rico, com três e quatro espécies nas Áreas I e II, respectivamente. As duas áreas de cerradão estudadas caracterizaram-se como uma transição, com espécies de Cerrado e espécies de Floresta Estacional. Os resultados das análises entre as variáveis do solo e a vegetação (parcelas) demonstraram que a ocorrência e a distribuição das espécies nas duas áreas não apresentaram um padrão com relação ao solo, sugerindo assim que outros fatores exercem maior influência para estas áreas no Pantanal, como a camada mais profunda do solo, diferença na posição no gradiente topográfico ou o tipo de drenagem do solo. / The objective of this study was to analyze the vegetation-soil relation of the tree flora of two areas of woodland savanna in a RPPN SESC Pantanal (Nature Patrimony Private Reserve – NPPR), Barão de Melgaço, state of Mato Grosso (16°37’S, 56°15’W). Five of 20 x 50 m plots were marked in each area and divided in sub-plots of 10m 2 , all tree individuals of diameter at breast height = 4.7 cm were sampled. The phytosociologic parameters, species richness and diversity were calculated. Composite samples for the soil analysis were collected in the surface layer (0-20 cm). A total of 72 species, in 56 genera and 28 botanic families were registered in the area of 1 ha; 9 and 30 species were exclusive to area I and II, respectively. The families Fabaceae, Malvaceae and Bignoniaceae were represented by the highest number of species. Genus Tabebuia was the richest, with 3 and 4 species in the Areas I and II, respectively. The two Cerradão areas under study were characterized as transition regions, since Cerrado as well as Seasonal Forest species were found. The analyses of soil and vegetation data (plots) showed no tendency of a relation between species occurrence and distribution and the soil in the two areas. This indicates that the influence of other factors is greater on these Pantanal areas, i.e., the deeper soil layer, difference in the position in the topographic gradient or the type of soil drainage. / Dissertação antiga
18

Estrutura geoelétrica da crosta superior revelada por dados magnetotelúricos 2d na bacia do Jaibaras, NW do Ceará / Geoeletric structure of upper crust revealed by 2d magnetotellurics data in the Jaibaras basin, Ceará NW.

Silva, Nilton Cesar Vieira January 2016 (has links)
SILVA, Nilton Cesar Vieira. Estrutura geoelétrica da crosta superior revelada por dados magnetotelúricos 2d na bacia do Jaibaras, NW do Ceará. 2016. 97 f. Dissertação (Mestrado em Geologia)-Universidade Federal do Ceará, Fortaleza, 2016. / Submitted by JOÃO CAVALCANTI JUNIOR (jbeniciojunior@yahoo.com.br) on 2017-07-13T12:26:04Z No. of bitstreams: 1 2016_dis_ncvsilva.pdf: 7471475 bytes, checksum: 3b090590e1ab516256dd34780c7cb072 (MD5) / Approved for entry into archive by Jairo Viana (jairo@ufc.br) on 2017-07-13T19:08:11Z (GMT) No. of bitstreams: 1 2016_dis_ncvsilva.pdf: 7471475 bytes, checksum: 3b090590e1ab516256dd34780c7cb072 (MD5) / Made available in DSpace on 2017-07-13T19:08:11Z (GMT). No. of bitstreams: 1 2016_dis_ncvsilva.pdf: 7471475 bytes, checksum: 3b090590e1ab516256dd34780c7cb072 (MD5) Previous issue date: 2016 / We have presented a magnetotelluric survey at 14 sites at Jaibaras Paleozoic Basin which is located in the northeastern part of Ceará, in municipalities of Mucambo and Pacujá. Basin structures were subjected to reactivation, influenced by Transbraziliano Lineament among others. In previous works, the reactivation of the so-called Sobral Pedro II lineament with gravity anomalies was interpreted as graben. The geological setting of this basin is still unknown, especially due to lack of detailed geophysical work. As well there were no direct geological information’s. With an integration of geological and geophysical data, 14 magnetotelluric sites was performed in order to understand the geoelectrical structure of the area, as an interpretation of two-dimensional MT section. Firstly, time series processing was preformed and 1-D inversion. After TE+TM mode inversion was done. The aim was to highlight crustal structure in the regional context with the help of geoelectrical inversion. It was possible to highlight shallow structures and delimitate between the geoelectrical units (horizontal structures) and contrasts between the vertical facies (vertical structures). MT section shows us that part of the Jaibaras rift was delimited with high-resistivity values which denote sub vertical structures, shear zones that are dipping in Jaibaras rift, part of the Transbrasiliano Lineament (Sobral-Pedro II shear zone). Other important lineaments have been identified such as Café-Ipueiras fault. Post-tectonic Mucambo granite and sediments of Parnaíba Basin looks clearly mapped. Two dimensional MT section presents a geoelectrical/geological interpretation of the upper part of the crust in that region. / Este trabalho apresenta resultados de 14 sondagens magnetotelúricas realizadas na bacia eo- paleozoica do Jaibaras localizada no noroeste do Estado do Ceará, envolvendo os municípios de Mucambo e Pacujá. As estruturas geradoras desta bacia sofreram reativações tectônicas, influenciadas pelo o lineamento Transbrasiliano, entre outros, localmente conhecido como Zona de Cisalhamento Sobral-Pedro II (ZCSPII), esta mesma região apresenta, em trabalhos prévios, baixos gravimétricos, interpretados como grábens. A configuração dessa bacia em subsuperfície ainda é desconhecida, sobretudo por falta de trabalhos detalhados de geofísica. A integração dos dados geológicos com as informações geofísicas, através de 14 sondagens magnetolúricas (MT) empreendidas com o objetivo de compreender o comportamento geoelétrico subsuperficial da região, que é apresentado através da interpretação de uma seção MT2D. Essa seção teve os dados de campo processados através de vários procedimentos nas séries temporais e inversão 1D dos dados. Finalmente, com o intuito de diminuir a interpretação ambígua realizou-se a inversão conjunta dos modos TE e TM (seção 2D), sendo apresentada a seção invertida MT2D. Esse processamento almejou realçar estruturas da crosta superior, além de informações sobre a estratigrafia elétrica da região, em contexto regional. Ainda, foi possível realçar estruturas de menor profundidade, delimitações de unidade geoelétricas (estruturas horizontalizadas) e contrastes de feições distribuídas verticalmente (estruturas verticalizadas). A seção MT2D mostra que esta porção do rifte Jaibaras é delimitada por altos valores de resistividade que denotam estruturas subverticais e estão relacionadas as zonas de cisalhamentos que balizam o rifte Jaibaras, dentre elas o Lineamento Transbrasiliano (Zona de Cisalhamento Sobral-Pedro II). Outros importantes lineamentos também puderam ser identificados, a exemplo da Falha Café-Ipueiras, bem como o Granito Mucambo e sedimentos da Bacia do Parnaíba. Por fim, a seção MT2D apresenta uma configuração geoelétrica/geológica preliminar da porção superior da crosta naquela região.
19

As faces e interfaces do processo de trabalho de enfermagem em instituições hospitalares de Cuiabá/MT

Moreira, Leocarlos Cartaxo January 2004 (has links)
Tese (doutorado) - Universidade Federal de Santa Catarina, Centro de Ciências da Saúde. Programa de Pós-graduação em Enfermagem / Made available in DSpace on 2012-10-21T21:08:34Z (GMT). No. of bitstreams: 0 / O processo de trabalho de enfermagem vem acumulando no transcurso de sua história, um conjunto de características, demonstrando ser um trabalho relacional, às vezes complementar, porém imprescindível, face à relevância da sua força de trabalho, produção de serviços empreendida nas instituições de saúde em geral, e, fundamentalmente, pela sua própria conformação, em estreita relação com os demais processos de trabalho na área de saúde. Essas dimensões foram decisivas para tomar o "processo de trabalho de enfermagem" como objeto de estudo dessa investigação. Os objetivos estabelecidos procuraram contemplar as diferentes dimensões do trabalho de enfermagem que envolvem: a natureza, o objeto, os instrumentos, as condições de trabalho e o olhar do trabalhador acerca daquilo que é produzido e vivido nos espaços hospitalares público e privado de Cuiabá/MT. O "lócus" da investigação deu-se em duas instituições hospitalares, sendo uma de natureza pública e outra privada. Os dados apreendidos através de observações sistemáticas e entrevistas, elaboradas a partir da realidade empírica investigada, apontaram configurações diversas, por vezes ambíguas; mostrando que a natureza, o objeto, os instrumentos e a conformação do trabalho são concebidos sob diferentes perspectivas, todavia, voltados para uma finalidade: a recuperação de corpos adoecidos. Analisou-se as condições injuntivas ao trabalho de enfermagem, que mostram peculiaridades em ambas as instituições, e, sobretudo, imprimem no trabalhador um frenético senso de ordenamento dos instrumentos de trabalho, disciplinarização no ato operatório de cuidar e um rígido monitoramento de sua produção. O comando efetivo dessas atividades recai sobre o enfermeiro, que passa a assumir a condução do processo de trabalho, numa clara diferenciação entre trabalho intelectual e manual, em aderência aos interesses institucionais. A absoluta hegemonia e centralidade do trabalho médico e o acentuado processo de divisão social e técnica no trabalho, acabam por reforçar uma condição de dominação-expropriação do trabalhador. Este, reconhecido como "agente" ou "executor" do processo de produção de cuidados, tende a se enquadrar mais na condição de sujeito objetificado do que de sujeito participante e transformador de uma prática laboral, que via de regra, desenha-se com características de parcelamento das tarefas, abundância de atividades, altos riscos, condições espúrias de trabalho e alienação, as quais estão intrinsecamente soantes com a racionalidade aplicada aos serviços de saúde. Mesmo dentro dessas delimitações, o trabalhador de enfermagem vislumbra possibilidades de resistência e objetivação, que emergem do cotidiano de seu ofício, por reconhecer, com lucidez e convicção, sua importância no espaço de trabalho que ocupa, almejando, no futuro, uma condição diferenciada e emancipatória no trabalho. The process of the work of nursing has accumulated through its history a series of characteristics showing that it is a job that is relation, at times complement but essential because of the importance of its work force, its services given in health institutions in general, and, mainly for its structure in strict relation to other jobs in the health area. These dimensions were decisive to make the "process of the work in nursing" as the aim of study of this investigation. The proposed aims attempted to focus on the different aspects of the nursing work that consists of the nature, the object, the instruments, the working conditions and the opinion of the worker about what is produced and lived in public and private hospitals of Cuiabá-MT. The "locus" of the investigation happened in two hospitals, one public and the other private. Data were collected through systematic observations and interviews based on empirical reality revealed various configurations, sometimes ambiguous showing that the nature, the object, the instruments and the organization of the work are seen under different perspectives, however with one objective: the recovery of sicks bodies. The conditions of working nursing analysed showed peculiarities in both institutions and above all give the worker a strong sense of order in the working instruments, discipline in the act of care and a rigid monitoration of production. The effective command of these activities fall on the nurse who conducts the working process separating clearly the intellectual work from the manual according to the institutional interest. The absolute supremacy and centrality of the medical work and the emphasized process of the social and technical division of the work reinforce a condition of domination-expropriation of the worker. This one known as "an agent" or a "doer" of the process of care production, fits more into the condition of an objectified subject instead of a participant subject and changer of a laboral practice that shows characteristics of a division of the tasks, excess of activities, high risks, bad working conditions, alienation which are intrinsically part of the rationality used in health care. Even with these limitations, the nursing worker sees possibilities of resistance and objectivity that emerge from the work place where they occupy, hoping to have in the future a different and emancipating condition. El proceso de trabajo de enfermería viene acumulando, en el transcurso de su historia, un conjunto de características, demostrando ser un trabajo relacional, algunas vezes complementario, sin embargo, inprescindible, frente a la relevancia de su fuerza de trabajo, producción de servicios, emprendida en las instituciones de salud en general, y, fundamentalmente, por su propia conformación, em relación estrecha con los demás procesos de trabajo en el área de salud. Esas dimensiones fueron decisivas para tomar el "Proceso de Trabajo de Enfermería" como objeto de estudio de esta investigación. Los objetivos establecidos procuraron contemplar las diferentes dimensiones del trabajo de enfermería que envuelven: la naturaleza, el objeto, los instrumentos, las condiciones de trabajo y la mirada del trabajador acerca de aquello que se produce y se vive en los espacios hospitalarios público y privado de Cuiabá/MT. El "locus" de la investigación se dió en dos instituciones hospitalares, siendo una de naturaleza pública y otra privada. Los datos obtenidos a través de observaciones sistemáticas y entrevistas, elaboradas a partir de la realidad empírica investigada, señalaron diversas configuraciones, algunas veces ambíguas; mostrando que la naturaleza, el objeto, los instrumentos y la confrontación del trabajo son concebidos bajo perspectivas diferentes, aún volcadas para una finalidad: la recuperación de cuerpos enfermos. Se analizó las condiciones impuestas al trabajo de enfermería, que muestran peculiaridades en ambas instituciones, y, sobretodo, imprimen en el trabajador un senso frenético de ordenamiento de los instrumentos de trabajo, disciplinización en el acto operativo de cuidar y un monitoriamento de su producción. El comando efectivo de esas actividades recae sobre el enfermero, que pasa a asumir la conducción del proceso de trabajo, en una clara diferenciciación entre trabajo intelectual y manual, en aderencia a los intereses institucionales. La hegemonía absoluta y centralización del trabajo médico y el acentuado proceso de división social y técnica en el trabajo, acaban reforzando una condición de dominación-expropiación del trabajador. Este, reconocido como "agente" o "ejecutor" del proceso de producción de cuidados, tiende a encuadrarse mas en la condición de sujeto objetivado, que de sujeto participante y transformador de una práctica laboral, que generalmente, se diseña con características de parcelamiento de las tareas, abundancia de actividades, altos riesgos, malas condiciones de trabajo y alienación, las cuales están intrínsicamente relacionadas con la racionalidad aplicada a los servicios de salud. Aún dentro de esas delimitaciones, el trabajador de enfermería vislumbra posibilidades de resistencia y objeticación, que emergen del cotidiano de su oficio, por reconocer, con lucidez y convicción, su importancia en el espacio que ocupa en el trabajo, construyendo, en el futuro, una condición diferenciada y emancipada en el trabajo.
20

Anisotropia crustal na região de Porto dos Gaúchos - MT, Brasil / Crustal anisotropy in Porto dos Gaúchos – MT, Brazil

Lemos, Davi Araújo Quaresma 10 April 2013 (has links)
Dissertação (mestrado)—Universidade de Brasília, Instituto de Geociências, 2013. / Submitted by Albânia Cézar de Melo (albania@bce.unb.br) on 2013-08-09T12:57:35Z No. of bitstreams: 1 2013_DaviAraujoQuaresmaLemos.pdf: 2568743 bytes, checksum: 66b39e735f60fb643fec4648105bfa29 (MD5) / Approved for entry into archive by Guimaraes Jacqueline(jacqueline.guimaraes@bce.unb.br) on 2013-08-09T14:32:04Z (GMT) No. of bitstreams: 1 2013_DaviAraujoQuaresmaLemos.pdf: 2568743 bytes, checksum: 66b39e735f60fb643fec4648105bfa29 (MD5) / Made available in DSpace on 2013-08-09T14:32:04Z (GMT). No. of bitstreams: 1 2013_DaviAraujoQuaresmaLemos.pdf: 2568743 bytes, checksum: 66b39e735f60fb643fec4648105bfa29 (MD5) / Nessa dissertação são apresentados dados de onda de cisalhamento registrados por uma rede sismográfica com três estações de três componentes dispostas em uma área com 12 km de diâmetro, nas proximidades de Porto dos Gaúchos (11°31’S, 57°24’O) no centro norte do estado do Mato Grosso. As estações ficaram operantes entre março de 2005 e julho de 2005 e uma delas continua em operação até a presente data. Essa rede tinha o objetivo de gravar as contínuas réplicas após o abalo principal de março de 2005. Foram feitas rotações de acordo com o azimute do evento à estação e à polarização nas ondas de cisalhamento, na tentativa de detectar a divisão da onda, e em caso positivo, identificar o tempo de atraso da onda S lenta e a direção de polarização da onda S rápida . O padrão da direção de polarização mostrado é consistente com a direção da foliação Pré-cambriana observada na área. Essa interpretação é baseada no fato de que a direção da onda S rápida concorda com a direção noroeste – sudeste da foliação Pré-cambriana. Essa conclusão está de acordo com do Nascimento et al.(2002, 2004), e tem importantes implicações na interpretação de observações da divisão de onda de cisalhamento feitas em rochas cristalinas na crosta, pois outros autores afirmam que essa divisão resulta dos efeitos das fraturas cheias de fluidos alinhadas ao esforço (anisotropia de dilatância extensiva - EDA). EDA é a assinatura do campo de esforço atual na região. Existe uma evidência com base no trabalho de Barros (2010), de que o máximo esforço compressional atualmente atuante na região tem direção E-W, sendo possível concluir que os dados obtidos estão em conflito com a interpretação da anisotropia em termos da EDA. ______________________________________________________________________________ ABSTRACT / In this dissertation we present splitting shear-wave data recorded at a three- component five-stations seismograph network distributed in a 12 km aperture, which operated from March 2005 to July 2005 near Porto dos Gaúchos (11°31'S, 57°24'W) - Brazil, to record the continued aftershocks activity after the main shock in March 2005, which had magnitude 5.0 m b. The pattern of polarization directions shown is consistent with the trend of Precambrian foliation observed in the field. This interpretation is based on the fact that the direction of the fastest splitting S wave agrees with the northwest-southeast trending Precambrian fabric. This conclusion, in accordance to those taken by do Nascimento et al (2002, 2004), has important implications for the interpretation of splitting shear-wave observations made in crustal crystalline rocks. Others authors have asserted that splitting shear-wave normally results from the effects of stress-aligned fluid-filled cracks (extensive dilatancy anisotropy or EDA). EDA is, by contrast, a signature of the present-day stress field in the region. There is strong evidence that in present-day maximum compressional stress is E-W direction. We therefore conclude that our present data are in conflict with an interpretation in terms of EDA.

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