Submitted by Andrei Francalacci de Castro Faria (andrei.francalacci@bndes.gov.br) on 2016-06-07T19:21:30Z No. of bitstreams: 1 Dissertação Andrei Francalacci.pdf: 2215041 bytes, checksum: 671600e92ce454211d0c6493c0ba75bc (MD5) / Approved for entry into archive by GILSON ROCHA MIRANDA (gilson.miranda@fgv.br) on 2016-06-10T12:18:57Z (GMT) No. of bitstreams: 1 Dissertação Andrei Francalacci.pdf: 2215041 bytes, checksum: 671600e92ce454211d0c6493c0ba75bc (MD5) / Approved for entry into archive by GILSON ROCHA MIRANDA (gilson.miranda@fgv.br) on 2016-06-20T16:21:18Z (GMT) No. of bitstreams: 1 Dissertação Andrei Francalacci.pdf: 2215041 bytes, checksum: 671600e92ce454211d0c6493c0ba75bc (MD5) / Made available in DSpace on 2016-06-27T18:56:29Z (GMT). No. of bitstreams: 1 Dissertação Andrei Francalacci.pdf: 2215041 bytes, checksum: 671600e92ce454211d0c6493c0ba75bc (MD5) Previous issue date: 2016-05-31 / We studied the effects on Petrobras shares arising from the presentation of the earnings announcements of 2014´s third and fourth quarter, the first announcements made after the beginning of the corruption investigation called Operação Lava Jato. We evaluate the impact on prices of the company's stocks with an Event Study. As a control, we analyzed the effects of the disclosure of 1,152 quarterly earnings announcements on other 48 stocks that are part of the IBOVESPA´s theoretical portfolio in the period between 2010 and 2015. We seek to identify the presence of abnormal returns and verify that all information is automatically transferred to prices, suggesting the semi-strong efficiency of the Brazilian stock market in accordance with the Market Efficiency Hypothesis (EMH) developed by Fama (1970). At the end we compare the results of the two specific earning announcements studied with the observed results of other earnings announcements of Petrobras. No evidence was found of market efficiency during the 2010-2015 period neither for the group of 48 stocks, NÃO_PETRO, nor for the PETRO group, formed by the two Petrobras shares. We then analyzed the results in two periods. The first, called Bonanza (2010-2013), showed the same results as the 2010-2015 period, with no significant abnormal returns in the event window [0,1]. The results of the Crisis period (2014 -2015) showed that the information of the earning announcements ha a statistical significant impacted on the prices of the studied stocks. To analyzing the results of the individual earning announcements of Petrobras, we identified the need for additional information, extrapolating the scope of an event study. / Este trabalho propõe-se a estudar os efeitos sobre as ações da Petrobras decorrentes da apresentação dos balanços do terceiro e quarto trimestre de 2014, primeiros balanços apresentados após as denúncias da Operação Lava Jato. Avaliamos os impactos nos preços das ações da empresa através de um Estudo de Evento. Como controle, analisamos os efeitos da divulgação de 1.152 balanços trimestrais sobre outras 48 ações de que fazem parte da Carteira Teórica do IBOVESPA no período entre 2010 e 2015. Buscamos identificar a presença de retornos anormais e verificar se toda informação se transfere automaticamente aos preços, sugerindo a eficiência semiforte do mercado de ações brasileiro de acordo com a Hipótese de Eficiência do Mercado (HEM) desenvolvida por Fama (1970). Ao final comparamos os resultados específicos dos balanços em estudo com os resultados observados em outros balanços da própria Petrobras. Não foram encontradas evidências de eficiência de mercado durante o período 2010-2015 nem para o grupo de 48 ações, chamadas de NÃO_PETRO, nem para o grupo PETRO, formado pelas duas ações da Petrobras. Ao dividir os mesmos grupos em dois momentos, os resultados para o período batizado de Bonança (2010-2013), permanecem iguais ao do período completo, ao passo que o período chamado de Crise (2014 -2015) apresenta retornos anormais estatisticamente significativos nas janelas de eventos. Ao avaliar os retornos de balanços individuais da Petrobras, identificamos a necessidade de informações adicionais, extrapolando o escopo de um estudo de evento.

Les arythmies sont des perturbations du rythme cardiaque qui peuvent entrainer la mort subite et requièrent une meilleure compréhension pour planifier leur traitement. Dans cette thèse, nous intégrons des données structurelles et fonctionnelles à un maillage 3D tétraédrique biventriculaire. Le modèle biophysique simplifié de Mitchell-Schaeffer (MS) est utilisé pour étudier l’hétérogénéité des propriétés électrophysiologiques (EP) du tissu et leur rôle sur l’arythmogénèse. L’ablation par radiofréquence (ARF) en éliminant les activités ventriculaires anormales locales (LAVA) est un traitement potentiellement curatif pour la tachycardie ventriculaire, mais les études EP requises pour localiser les LAVA sont longues et invasives. Les LAVA se trouvent autour de cicatrices hétérogènes qui peuvent être imagées de façon non-invasive par IRM à rehaussement tardif. Nous utilisons des caractéristiques d’image dans un contexte d’apprentissage automatique avec des forêts aléatoires pour identifier des aires de tissu qui induisent des LAVA. Nous détaillons les sources d’erreur inhérentes aux données et leur intégration dans le processus d’apprentissage. Finalement, nous couplons le modèle MS avec des géométries du coeur spécifiques aux patients et nous modélisons le cathéter avec une approche par un dipôle pour générer des électrogrammes normaux et des LAVA aux endroits où ils ont été localisés en clinique. Cela améliore la prédiction de localisation du tissu induisant des LAVA obtenue par apprentissage sur l’image. Des cartes de confiance sont générées et peuvent être utilisées avant une ARF pour guider l’intervention. Les contributions de cette thèse ont conduit à des résultats et des preuves de concepts prometteurs. / Cardiac arrhythmias are heart rhythm disruptions which can lead to sudden cardiac death. They require a deeper understanding for appropriate treatment planning. In this thesis, we integrate personalized structural and functional data into a 3D tetrahedral mesh of the biventricular myocardium. Next, the Mitchell-Schaeffer (MS) simplified biophysical model is used to study the spatial heterogeneity of electrophysiological (EP) tissue properties and their role in arrhythmogenesis. Radiofrequency ablation (RFA) with the elimination of local abnormal ventricular activities (LAVA) has recently arisen as a potentially curative treatment for ventricular tachycardia but the EP studies required to locate LAVA are lengthy and invasive. LAVA are commonly found within the heterogeneous scar, which can be imaged non-invasively with 3D delayed enhanced magnetic resonance imaging (DE-MRI). We evaluate the use of advanced image features in a random forest machine learning framework to identify areas of LAVA-inducing tissue. Furthermore, we detail the dataset’s inherent error sources and their formal integration in the training process. Finally, we construct MRI-based structural patient-specific heart models and couple them with the MS model. We model a recording catheter using a dipole approach and generate distinct normal and LAVA-like electrograms at locations where they have been found in clinics. This enriches our predictions of the locations of LAVA-inducing tissue obtained through image-based learning. Confidence maps can be generated and analyzed prior to RFA to guide the intervention. These contributions have led to promising results and proofs of concepts.

[pt] A presente dissertação investiga e analisa a instrumentalização do processo penal, convertido em arma de guerra – lawfare -, para viabilizar práticas autoritárias punitivas amparadas no casuísmo, no âmbito da chamada Operação Lava Jato, bem como analisa o manejo/utilização/implementação de mecanismos de exceção dentro da rotina democrática brasileira com o fim de eliminar um inimigo personificado na figura do ex-presidente Lula, objetivando retirá-lo da corrida eleitoral de 2018, estabelecendo, assim, a consolidação do golpe iniciado em 2016, com a derrubada da Presidenta Dilma Rousseff. O trabalho discute a Operação Lava Jato abordando o fenômeno do intercruzamento entre direito e política (ativismo judicial, judicialização da política e politização da justiça), analisando criticamente a atuação da grande mídia hegemônica oligopolista brasileira. Desta forma, esta pesquisa enfrenta essa questão a partir do fenômeno identificado como lawfare. No capítulo introdutório, é apresentado o tema, problema, hipóteses, objeto da pesquisa, a justificativa do trabalho, referencial teórico e metodologia da pesquisa. No segundo capítulo são apresentadas algumas abordagens conceituais sobre o termo lawfare, desenvolvidas por diversos intelectuais que se debruçaram sobre o tema, trazendo a discussão para o contexto brasileiro. No terceiro capítulo, analisase o lawfare para fins geopolíticos e empresariais, a extraterritorialidade coercitiva universal estadunidense e como esse emaranhado de legislação internacional impacta na soberania econômica do Brasil. No quarto capítulo defende-se que a Operação Lava Jato foi um maxiprocesso jurídico-político-midiático utilizado como instrumento de lawfare, interferindo no realinhamento de forças políticas no país e abrindo caminho para implantação de um governo neoliberal extremado, com suporte da mídia hegemônica oligopolista e da ofensiva restauradora do campo neoliberal ortodoxo. No Anexo 1, apresenta-se parte das mensagens periciadas pela Polícia Federal no bojo da Operação Spoofing. No anexo 2, apresenta-se a decisão favorável ao ex-Presidente Lula, proferida pelo Comitê de Direitos Humanos da ONU. / [en] The present dissertation investigates and analyzes the instrumentalization of the criminal process, converted into a weapon of war - lawfare -, to enable punitive authoritarian practices supported by casuism, within the scope of the so-called Operation Car wash, as well as analyzing the management/use/implementation of mechanisms of exception within the Brazilian democratic routine in order to eliminate an enemy personified in the figure of former President Lula, aiming to remove him from the 2018 electoral race, thus establishing the consolidation of the coup that began in 2016, with the overthrow of President Dilma Rousseff. The paper discusses Operation Car Wash addressing the phenomenon of the intersection between law and politics (judicial activism, judicialization of politics and politicization of justice), critically analyzing the performance of the Brazilian oligopolistic hegemonic media. Thus, this research addresses this issue from the phenomenon identified as lawfare. In the introductory chapter, the theme, problem, hypotheses, research object, work justification, theoretical framework and research methodology are presented. The second chapter presents some conceptual approaches to the term lawfare, developed by several intellectuals who have focused on the subject, bringing the discussion to the Brazilian context. In the third chapter, we analyze lawfare for geopolitical and business purposes, the universal coercive extraterritoriality of the United States and how this tangle of international legislation impacts Brazil s economic sovereignty. In the fourth chapter it is argued that Operation Car Wash was a legal-political-media maxi-process used as an instrument of lawfare, interfering in the realignment of political forces in the country and opening the way for the implantation of an extreme neoliberal government, with the support of the oligopolistic hegemonic media. and the restorative offensive of the orthodox neoliberal camp. In Annex 1, part of the messages examined by the Federal Police in the context of Operation Spoofing is presented. Annex 2 presents the decision in favor of former President Lula, delivered by the UN Human Rights Committee.

Submitted by Filipe dos Santos (fsantos@pucsp.br) on 2018-06-26T12:35:22Z No. of bitstreams: 1 Rayssa Pereira do Nascimento Mendes.pdf: 1005048 bytes, checksum: 95f1d9ed418e3c6a58dacf51908292e7 (MD5) / Made available in DSpace on 2018-06-26T12:35:22Z (GMT). No. of bitstreams: 1 Rayssa Pereira do Nascimento Mendes.pdf: 1005048 bytes, checksum: 95f1d9ed418e3c6a58dacf51908292e7 (MD5) Previous issue date: 2018-03-23 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / This research aims to investigate the relation between Petrobrás and the current political crisis in Brazil. As part of a strategic sector, the state company was the target of uncountable onslaughts in the beginning of Operation Car Wash, what has spotlighted it in front of public opinion, through certain media approaches. The theoretical framework setting this analysis is the propositions of John B. Thompson about the structuring of political scandals, having the reputation of Petrobrás as its core element under dispute. Firstly, we will describe a historical, economic and geopolitical overview of the state company, which demonstrates its importance and, accordingly, potential interests that it awakes in a global scenery whose actors guide their conflicts by the production and trade of petroleum. We will present elements that compose the context of Petrobrás, aiming to illustrate how such a political crisis was significantly viable thanks to the strategic position of the company. It has allowed the construction and legitimation of the Operation Car Wash in front of public opinion, which constitutes the national political crisis scenery of current years. The operation emerges in a very “convenient” moment: 2014, during the global crisis of petroleum. However, nor the international crisis of petroleum or any of those historical events were mentioned by the major media vehicles at that moment. Thus, the methodology of agenda setting and framing of these major media vehicles is fundamental to understand how the political crisis scenery – and the Operation Car Wash – were shaped by a discourse of crisis of Petrobrás. Finally, we will observe some actors involved in the construction of such scandal – and of the crisis, therefore – in order to understand how they articulate (currently and in the past) through the exercise of symbolic power, which is subjective by definition. Despite this subjectivity, these actors – judicial power and major media vehicles – act with a supposed neutrality and objectivity, expressively influencing the political and economic scenery. Such alliance aims to delegitimise the traditional political class, not contributing to a more consistent and effective articulation of the public debate, majorly affecting Petrobrás and Democracy itself at different levels / Esta pesquisa tem por objetivo investigar a relação entre a Petrobrás e a atual crise política no Brasil. Por se tratar de um setor estratégico, a estatal foi alvo de inúmeras ofensivas no início da Operação Lava Jato, o que contribuiu, a partir de determinadas abordagens midiáticas, para que a operação ganhasse destaque perante a opinião pública. Tal análise tem como referencial teórico as proposições de John B. Thompson no que diz respeito à estruturação dos escândalos políticos, tendo a reputação da Petrobrás como elemento central de disputa. Assim, primeiramente, procuraremos descrever um panorama do contexto histórico, econômico e geopolítico da estatal, que demonstra a sua importância e, por consequência, possíveis interesses que desperta,em um cenário global cujos atores têm seus conflitos pautados pela produção e comercialização do petróleo.Apresentaremos elementos que compõem o contexto da Petrobrás, procurando ilustrar como uma crise política de tal dimensão foi grandemente viabilizada pela posição estratégica da empresa, permitindo a construção e legitimação da Operação Lava Jato perante a opinião pública, que comporiam, ao longo dos últimos anos, um cenário de crise política nacional. Aoperação surge em um momento bastante “propício”: o ano de 2014 vivenciou uma crise do petróleo, em âmbito global. No entanto, nem a crise internacional do petróleo ou qualquer desses elementos históricos foram abordados naquele momento pelos jornais de grande circulação brasileiros. Assim, a utilização de aspectos metodológicos das teorias de agendamento e enquadramento para a análise discursiva, observando a atuação de alguns desses veículos midiáticos, é fundamental para um melhor entendimento de como o cenário de crise política – e a Operação Lava Jato – se emolduraram a partir de um discurso de crise da Petrobrás. Por fim, observaremos alguns dos atores envolvidos na construção desse escândalo – e da crise, por extensão-, procurando entender como se articularam e articulam a partir do exercício do poder simbólico, subjetivo por definição. Apesar dessa subjetividade, esses atores –Poder Judiciário e veículos de comunicação em massa - atuam com pretensa neutralidade e objetividade, influenciando grandemente o cenário político e econômico. Tal aliança visa a deslegitimação da classe política tradicional sem contribuir para que o debate público seja articulado de forma consistente e efetiva,de modo que, em diferentes escalas, seus prejuízos acabam por afetar, majoritariamente, a Petrobrás e a própria Democracia

Submitted by (lucia.rodrigues@ufrpe.br) on 2017-02-21T13:55:26Z No. of bitstreams: 1 Cicero Nicolini.pdf: 1169299 bytes, checksum: e932282294084c1947939ed928971bcb (MD5) / Made available in DSpace on 2017-02-21T13:55:26Z (GMT). No. of bitstreams: 1 Cicero Nicolini.pdf: 1169299 bytes, checksum: e932282294084c1947939ed928971bcb (MD5) Previous issue date: 2011-09-01 / Conselho Nacional de Pesquisa e Desenvolvimento Científico e Tecnológico - CNPq / Brazil is the world’s largest passion fruit producer. The sanitary problems, mainly diseases caused by viruses are among the limiting factors for increasing productivity and longevity of the plantations. In Brazil, passion fruit woodiness, caused by Cowpea aphid-borne mosaic virus (CABMV) is the major viral disease of this crop. CABMV is also causing agent of the potyvirus mosaic, a viral disease that produces serious damages in cowpea. This crop in Brazil is important mainly in the Northeastern region and represents a relevant source of protein and starch for the population. Some years ago, in the state of Pernambuco it was found a potyvirus naturally infecting “lava-pratos”, leguminous plant native to Atlantic Forest commonly found on the margins of passionflower and cowpea crops. In the city of Paudalho it was found a group of “lava-pratos” plants presenting very intense symptoms with yellow spot on the leaves. From those plants, preparations examined in a transmission electron microscope showed the presence of elongated flexuous particles and cylindrical inclusions typical of potyvirus as well as isometric particles in high concentration and vesicles on the periphery of the chloroplasts which suggested the occurrence of a tymovirus. Serological analyses and coat protein sequencing to identify the potyvirus as well as studies on host adaptation in passionflower and cowpea, using isolates from these crops were undertaken. The virus with isometric particles was chemically purified to produce polyclonal antiserum and subjected to serological studies, host range and genome sequencing for characterization. It was concluded that the potyvirus found in “lava-pratos” is CABMV and phylogenetically observed the host adaptation of this virus to the families Fabaceae and Passifloraceae. For some strains geographical distance was not the strongest factor for genetic grouping and the Brazilian isolates form a large group distinct to other countries. According to the criteria of taxonomy, using amino acid sequence of coat protein and conserved region "tymobox", it was determined the presence of a tymovirus in “lava-pratos”, for which was proposed to be a new species named Cassia yellow mosaic-associated virus (CAYMaV). / O Brasil é o maior produtor mundial de maracujá. Os problemas fitossanitários especialmente as doenças ocasionadas por vírus estão entre os fatores limitantes ao aumento de produtividade e longevidade dos plantios. A principal virose do maracujazeiro no Brasil é o endurecimento dos frutos causado por Cowpea aphid-borne mosaic virus (CABMV). O CABMV também é o agente do mosaico de potyvírus em feijão-caupi, virose que provoca sérios danos nessa cultura. No Brasil, o feijão-caupi é produzido principalmente na Região Nordeste e representa fonte importante de proteína e amido para a população. Há alguns anos atrás, um potyvírus foi encontrado em Pernambuco infectando naturalmente o lava-pratos, uma leguminosa nativa da Mata Atlântica comumente encontrada nas bordas de cultivos de maracujá e feijão-caupi. No município de Paudalho foi observado um grupo de plantas de lava-pratos apresentando sintomas muito intensos com manchas amarelas nas folhas. Dessas plantas, ao ser analisadas preparações em microscópio eletrônico de transmissão, além da presença de partículas alongadas flexuosas e de inclusões cilíndricas típicas de potyvírus foram detectadas partículas isométricas em alta concentração e vesículas nas bordas dos cloroplastos, o que sugeria ser de um tymovírus. Foram realizadas análises sorológicas e seqüenciamento da capa protéica para identificação do potyvírus, assim como estudar a adaptação hospedeira a maracujazeiro e feijão-caupi, utilizando-se isolados obtidos dessas culturas. O vírus com partículas isométricas foi purificado quimicamente para produção de antissoro policlonal e submetido a estudos sorológicos, gama de hospedeiros e seqüenciamento de parte do genoma para caracterização. Concluiu-se que o potyvírus encontrado em lava-pratos é o CABMV e filogeneticamente se observou que ocorre adaptação hospedeira deste vírus em plantas das famílias Fabaceae e Passifloraceae. Para alguns isolados, a distância geográfica não foi o fator mais forte para agrupamento genético e os isolados brasileiros formam um grande grupo distinto aos de outros países. De acordo com os critérios de taxonomia, usando-se seqüência de aminoácidos da capa protéica e região conservada “tymobox”, foi determinada a presença em lava-pratos de um tymovírus, para o qual foi proposto ser uma nova espécie nomeada Cassia yellow mosaic-associated virus (CAYMaV).

Throughout its eruptive history, Mount Hood has produced compositionally similar calc-alkaline andesite as lava flows and domes near the summit and basaltic andesitic flows from flank vents. Found within the andesite are slightly more mafic inclusions that are compositionally similar to the host andesite (or host lavas); no inclusions were found in the flank lavas. Host lavas and inclusions have the following mineral assemblage: plag + opx ± cpx ± amp + oxides. Flank lava mineralogy is similar to the inclusions and host lavas, but since they are more mafic they contain olivine instead of amphibole. Average silica content among samples analyzed ranges from 57.6 to 62.7 weight percent; however the incompatible trace element composition is more variable at lower silica contents and becomes less variable at higher silica contents. In terms of incompatible trace element composition, the host lavas and inclusions are either depleted (no amp) or enriched (amp± cpx).

Instrumental Neutron Activation Analysis (INAA) was used to identify geochemical groups in Boring Lava along the west side of the Tualatin Mountains, and in sediments of the Portland and Tualatin basins. Samples of Boring Lava were obtained from TriMet drill core collected during planning of the tunnel alignment for the Westside Light Rail line. Additional samples of Boring Lava were collected from outcrops along the west side of the Tualatin Mountains. Samples of sediment from the Tualatin and Portland basins were obtained from drill core collected during an Oregon Department of Geology and Mineral Industries (DOGAMI) Earthquake Hazards Mapping project. INAA of Boring Lava samples resulted in the identification of three geochemical groups. Additional data sets, including x-ray fluorescence geochemistry, magnetic polarity, and age dates, allowed for the distinction of three Boring Lava units. The Boring Lava of Barnes Road is a young, normal unit, the Boring Lava of Sylvan Hill is an older normal unit, and the Boring Lava of Cornell Mountain is the oldest, reversed unit. The surf ace distribution, identified using topography and outcrop geochemistry, is consistent with the subsurface distribution, identified using boring logs and core geochemistry. Volcanic vent locations are proposed at topographic highs within the identified surface distribution of the Boring Lava of Barnes Road. INAA of sediment samples resulted in the identification of seven groups: (1) Columbia River source sediments, (2) lower Troutdale Formation, (3) Reed Island ashes, (4) young Columbia River sediments, (5) highalumina basalt sediments, (6) episodic Cascadian volcanic sediments, and (7) Columbia River Basalt Group (CRBG) sediments. Only the CRBG sediments group was identified in the Tualatin basin, while all seven groups were identified in the Portland basin. This appears to demonstrate that the sediment packages in the two basins are different. Finally, each sediment group can be placed into one of three broad geochemical categories: Columbia River source sediments and lower Troutdale Formation represent a Columbia River or continental source; Reed Island ashes, young Columbia River sediments, high-alumina basalt sediments, and episodic Cascadian volcanic sediments represent a Cascadian or local source; and CRBG sediments represent residual soils or sediments overlying Columbia River basalt flows.

Understanding continental crust formation and modification is a fundamental and longstanding geologic problem. Influx of mantle-derived basaltic magma and partial melting of the crust are two ways to drive crustal differentiation. This process results in a low density upper crust and denser, more refractory lower crust, creating significant and vastly different geochemical reservoirs over time. The High Lava Plains (HLP) and Northwestern Basin and Range (NWBR) in central and eastern Oregon provide an excellent example of intraplate volcanism where we can examine the beginnings of segregation of a relatively young, recently accreted crust. The origins of continental magmatism and its relationship to plate tectonics, especially away from the continental margins, are only slowly becoming revealed. The western United States is the most volcanically active part of North America during Cenozoic time, and this activity includes the enigmatic volcanism of the HLP and NWBR. Rhyolitic volcanism in the HLP and NWBR is age-progressive but in a direction that is nearly perpendicular to North American Plate motion. Despite being erupted through a similar crust and with a similar composition of mafic input, the HLP province is strongly bimodal (basalt-rhyolite) while the NWBR province exhibits a continuum of compositions. High silica rhyolites are commonplace in the HLP, with approximately a 1:1 ratio of rhyolite to basalt, even though the crust is comprised of mafic accreted terranes. Asthenospheric flow, mantle melting and crustal extension coupled with southwesterly North American plate motion explain the age-progressive volcanism of the HLP and NWBR. Differential asthenopheric counterflow and mantle upwelling created by the down-going Cascadia slab, coupled with transtensional stresses related to the rotation of the North American plate and Basin and Range extension, decreasing to the north, can produce the observed variations in rhyolite compositions and volumes in the two adjacent provinces. These differences are caused by fundamentally different petrogenetic processes that take place in the crust. In the HLP, an increase in mantle-derived magma flux into the lower crust has created low silica rhyolite via partial melt that separated, coalesced and rose buoyantly. This low silica rhyolite may erupt, solidify in the upper crust, or differentiate by fractional crystallization to produce high-iron, high-silica rhyolite containing an anhydrous phase assemblage. In the NWBR, a smaller flux of basaltic magma, coupled with greater transtension resulted in small crustal processing zones where fractional crystallization coupled with magma mixing and recharge created a wide range of compositions. Partial melting to form rhyolites was limited. These rhyolites have lower iron, and hydrous phases (biotite, amphibole) are common. These processes modify the crust in different ways, leaving a stratified crust in the HLP but a less modified crust in the NWBR. Recent geophysical and isotopic studies bear out these differences and allow for a unified, internally consistent model for both provinces, one that relies only on partial melt generation driven by current plate movements and do not require a mantle plume contribution. The bimodal volcanism of the HLP is a direct consequence of the processes that cause the gravitational differentiation of the continental crust into upper and lower units. The model for the HLP is generally applicable to other localities that have predominantly mafic crust and a similar balance of crustal transtension and mantle-derived basaltic flux. One such place is Iceland, which has strongly bimodal (basalt – rhyolite) volcanism. In areas where silicic crust has become substantially more mafic due to a high flux of intraplated basalts, such as in the bimodal Snake River Plain, the model is also applicable. / Graduation date: 2012 / In order for the .age files to run, the add-in called ArArCalc for Excel (version 200 or 2003) must be installed. ArArCalc is available from the website Earthref.org

Graduation date: 2002

No description available.