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Levantamento gravimétrico na Jazida Carbonífera Morungava-Chico Lomã, RSCavalheiro, Mara Lia Dias January 2016 (has links)
A presente dissertação foi desenvolvida conforme a norma 103 do Programa de Pós Graduação em Geociências da Universidade Federal do Rio Grande do Sul, que prevê a submissão da dissertação de mestrado em forma de artigo, antecedido de estado da arte do tema proposto. Na região sudeste da Bacia do Paraná estão localizados depósitos de carvão economicamente importantes nos estados do Paraná, Santa Catarina e Rio Grande do Sul. Esses depósitos são frequentemente muito alterados por intrusões vulcânicas. O objetivo principal desse estudo é mapear essas intrusões ígneas que afetam o nível de alteração térmica do carvão (rank) da Jazida carbonífera Morungava-Chico Lomã no RS. A Jazida Morungava-Chico Lomã foi descoberta no século passado e nunca foi minerada. É caracterizada por rochas orgânicas do Permiano, carvão e folhelho betuminoso, na porção sul da Bacia do Paraná. A aquisição gravimétrica foi realizada na área do depósito Morungava e na área do depósito Chico-Lomã. Para ambas a escolha dos locais de aquisição foi baseada em furos de sondagem anteriormente realizados. Com os dados dos furos de sondagem foram elaborados seguintes mapas temáticos: profundidade da primeira ocorrência de carvão; espessura cumulativa do carvão; profundidade da primeira ocorrência de diabásio; espessura cumulativa do diabásio; espessura cumulativa do diabásio na Formação Irati e espessura cumulativa do diabásio na Formação Rio Bonito. Na elaboração do artigo submetido foi realizada a sobreposição das isolinhas das espessuras cumulativa do carvão e do diabásio nos mapas de anomalia Bouguer filtrados. Essas sobreposições apresentaram correlações e auxiliaram na interpretação dos dados gravimétricos. A orientação preferencial predominante das anomalias foi NE-SW e uma orientação subsidiária de direção NW-SE, o que sugeriu um controle estrutural sobre a ocorrência de diques e/ou soleiras, sob os altos gravimétricos. Em Chico Lomã a ocorrência de uma extensa anomalia Bouguer positiva formando um trend de orientação NE-SW foi correlacionada a unidades geológicas da Planície Costeira do Rio Grande do Sul: altos gravimétricos caracterizaram a Barreira I e baixos gravimétricos, os Sistemas Lagunares I e II. O método gravimétrico se mostrou eficaz para a caracterização da jazida por meio da correlação de anomalias gravimétricas positivas com as ocorrências de diabásio. / The present dissertation was developed according to standard 103 of the Graduate Program in Geosciences of the Federal University of Rio Grande do Sul, which provides for the submission of the dissertation in the form of article, predates by state of the art proposed theme. In the southeastern region of the Paraná Basin are located economically important coal deposits in the states of Parana, Santa Catarina and Rio Grande do Sul. These deposits are often much altered by volcanic intrusions. The objective of this study is to map the igneous intrusions affecting the thermal change of level of coal (rank) of the coal deposit Morungava-Chico Lomã in RS. The coal deposit Morungava-Chico Lomã was discovered in the last century and has never been mining. It is characterized by organic rocks of the Permian, coal and bituminous shale, in the southern portion of the Paraná Basin. The gravimetric acquisition was carried in área of the deposit Morungava and in the area of the deposit Chico-Lomã. For both areas the choice of acquisition locations was based on previously conducted drilling holes. With data from the holes drilling were prepared these thematic maps: depth of the first occurrence of coal; cumulative thickness of coal; depth of the first occurrence of diabase; cumulative thickness of diabase; cumulative thickness of diabase in Irati Formation and cumulative thickness of the diabase in Rio Bonito Formation. In the elaboration of article submitted the overriding of the isolines of cumulative thickness of coal and diabase in the filtered Bouguer anomaly maps was performed. These overrides presented correlations and assisted in the interpretation of gravity data. The predominant preferential orientation of the anomalies was NE-SW and a subsidiary orientation NW-SE direction, suggesting a structural control on the occurrence of dikes and/or sills, on gravimetric high. In Chico Lomã the occurrence of an extensive positive Bouguer anomaly forming a trend of NE-SW orientation was correlated with geological units of Rio Grande do Sul Coastal Plain: gravimetric characterized the high Barrier I and low gravimetric, Systems Lagunar I and II. The gravimetric method proved efficient for the characterization of the deposit through the correlation of positive gravity anomalies with occurrences of diabase.
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Traumatic imagery after life-threatening cardiac eventsCurley, Alexandra Paula Marie January 2013 (has links)
Aims There is a growing body of evidence that some individuals are at risk of developing post-traumatic stress disorder (PTSD) after life-threatening cardiac events, such as myocardial infarction (MI) or cardiac arrest, which can result in distress, dysfunction and increased risk of mortality. In relation to this population, this thesis had two aims: to review the evidence regarding whether pain during MI predicts post-traumatic stress symptoms; and to explore the characteristics and impact of traumatic imagery experienced by individuals who develop symptoms of post-traumatic stress subsequent to MI or cardiac arrest. Methods A review of the evidence relating to pain as a potential risk factor for PTSD subsequent to MI is presented in the systematic review. The findings from a qualitative study investigating the characteristics of traumatic imagery and associated behaviours experienced by individuals who have symptoms of post-traumatic stress subsequent to MI or cardiac arrest, are presented in the journal article. Interpretative Phenomenological Analysis (IPA) was used to identify themes in the data. Results The systematic review indicated that there are mixed findings for pain as a risk factor for PTSD subsequent to MI. The limited number of studies in this area and significant methodological limitations within the existing evidence make it difficult to draw any firm conclusions with regard to the relationship between pain and PTSD post-MI. With regard to the qualitative study, the majority of imagery related to flashbacks of the event and were focused mainly on external experiences. Themes arising from the distressing flashback imagery included: loss of control; realisation of threat; negative impact on others; physical sensations; and actions of others. Imaginary elements and distortions were a feature of some traumatic imagery experienced, and non-flashback imagery connected with mortality was also experienced. Imagery was associated with avoidance behaviour and affected behaviour within relationships. Conclusions Findings from the systematic review indicate that further studies are warranted in this area to establish the link between pain and PTSD post-MI. These studies should seek to address methodological limitations of the current evidence by using a standardised pain measurement tool; adopting a prospective design; using a diagnostic tool to measure PTSD; ensuring PTSD is measured at least one month after the MI; assessing prior PTSD of non-cardiac origin; including a sufficient sample size and using an appropriate method of recruitment to improve generalisability. External experiences during a cardiac event are the main focus of traumatic visual imagery experienced by people with intrusive post-traumatic stress symptoms post cardiac event. Specific aspects of the cardiac event may be particularly distressing and these may be represented in post-traumatic visual imagery. Both gradual exposure and imagery rescripting techniques may be useful for reducing distress associated with the imagery, depending on the type of imagery experienced.
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Geothermal Potential of Sub-Volcanic Intrusions in a Typical Caldera Setting / Geotermisk potential av magma-intrusioner i en calderavulkanGestsson, Einar Bessi January 2018 (has links)
Sub-volcanic intrusions can form an extensive network of sills, dikes and other intrusion types that make up a plumbing system beneath volcanoes. Such intrusions are the heat source for high-temperature geothermal systems in volcanic areas and therefore, it is of great importance to study them in relation to geothermal exploration and production. In this thesis a part of the plumbing system of Breiðuvík caldera, an eroded central volcano in northeastern Iceland, is studied. A set of magmatic intrusions showing a great range in size and shapes, is exposed in Leirfjall, a mountain composed of the eroded caldera infill of the Breiðuvík volcanic system. Data from these intrusions and their host rock is used as the foundation for numerical modeling using finite element method (FEM) constructed in this thesis. The numerical modeling assumes heat transfer in porous media including conduction and convection where fluid flow is governed by the Darcy‘s law. The aims of it is to compare the cooling times of different intrusions and the temperature distribution caused by intrusions of different sizes and shapes. To obtain input parameters for the numerical modeling, a thermometry study based on the mineral chemistry of the magmatic intrusions in Leirfjall is conducted and the thermal and physical properties of the sedimentary host rock are estimated, while literature values are used for basaltic lava and hyaloclastite host rocks for comparison. The results of the numerical modeling suggest that higher maximum values of increased temperature are reached above one thick intrusions compared to multiple thinner intrusions. When comparing dikes and sills, the dikes raise the maximum temperature of the host rock more than the sills, while the sills raise the average temperature above the intrusions more than dikes. Results of the estimated heat transfer from an arrangement of intrusions similar to what is observed in Leirfjall suggests that a significant increase in maximum increased temperature caused by the intrusions would be short-lived, while the average increase would still be constant over a longer time. Despite of the simplified structure of the numerical models it is the hope that they will provide inspiring data for further research and contribute to a better understanding of the relationship between the shallow magmatic intrusions and geothermal systems. / Vulkaner är en viktig energikälla i många länder runt om i världen. Geotermisk vätska och ånga av högtemperatur som finns i vulkanområden kan utnyttjas för bland annat elproduktion och fjärrvärme. Värmekällan till de geotermiska områdena är magma som ligger ytligt i jordskorpan. All magma når inte ytan i utbrott, utan stannar under vulkanen i form av magmaintrusioner. Intrusionerna av olika former och storlekar utgör ett nätverk som tillsammans utgör vulkanens magma transportsystem. I denna studie studeras en uppsättning av magmaintrusioner på nordöstra Island. Intrusionerna har en gång befunnit sig längre ner i jordskorpan under ett aktivt vulkanområde men exponeras nu vid ytan på grund av glacial erosion. Intrusionernas storlek och form varierar, men de flesta återfinns som gångar, både vertikala och horisontella. När en magmatintrusion bildas värms omkringliggande berggrund och grundvatten upp. Studiens fokus är att undersöka hur temperaturfördelningen i omgivningen skiljer sig vid en stor intrusion jämfört med flera mindre intrusioner med totalt samma volym. Även effekten från olika typer av berggrund runt intrusionerna studerades genom att jämföra temperaturfördelningen och kylningstiderna för intrusioner i tre vanliga bergarter. Numerisk modellering användades för att besvara dessa frågor. Bergarternas fysiska och termiska egenskaper krävdes som ingångsparametrar för den numeriska modelleringen. Parametrana uppskattades genom laboratorieexperiment och termometriberäkningar från fältprover. Värden från publicerat material användes också i modelleringen. Resultaten från den numeriska modelleringen antyder att högre maximivärden för temperaturen nås i berget över en stor, enskild intrusion jämfört med flera mindre intrusioner. När man jämför vertikala og horisontella gångar, ökar de vertikala gångarna berggrundens temperatur mer än de horisontella, medan medeltemperaturen ökar mer över horisontella gångar än i vertikala gångar. Trots den numeriska modellens förenklade struktur är förhoppningen att den nya datan kan inspirera vidare forskning, och bidra till en bättre förståelse om förhållandet mellan grunda magmaintrusioner och geotermiska system.
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Levantamento gravimétrico na Jazida Carbonífera Morungava-Chico Lomã, RSCavalheiro, Mara Lia Dias January 2016 (has links)
A presente dissertação foi desenvolvida conforme a norma 103 do Programa de Pós Graduação em Geociências da Universidade Federal do Rio Grande do Sul, que prevê a submissão da dissertação de mestrado em forma de artigo, antecedido de estado da arte do tema proposto. Na região sudeste da Bacia do Paraná estão localizados depósitos de carvão economicamente importantes nos estados do Paraná, Santa Catarina e Rio Grande do Sul. Esses depósitos são frequentemente muito alterados por intrusões vulcânicas. O objetivo principal desse estudo é mapear essas intrusões ígneas que afetam o nível de alteração térmica do carvão (rank) da Jazida carbonífera Morungava-Chico Lomã no RS. A Jazida Morungava-Chico Lomã foi descoberta no século passado e nunca foi minerada. É caracterizada por rochas orgânicas do Permiano, carvão e folhelho betuminoso, na porção sul da Bacia do Paraná. A aquisição gravimétrica foi realizada na área do depósito Morungava e na área do depósito Chico-Lomã. Para ambas a escolha dos locais de aquisição foi baseada em furos de sondagem anteriormente realizados. Com os dados dos furos de sondagem foram elaborados seguintes mapas temáticos: profundidade da primeira ocorrência de carvão; espessura cumulativa do carvão; profundidade da primeira ocorrência de diabásio; espessura cumulativa do diabásio; espessura cumulativa do diabásio na Formação Irati e espessura cumulativa do diabásio na Formação Rio Bonito. Na elaboração do artigo submetido foi realizada a sobreposição das isolinhas das espessuras cumulativa do carvão e do diabásio nos mapas de anomalia Bouguer filtrados. Essas sobreposições apresentaram correlações e auxiliaram na interpretação dos dados gravimétricos. A orientação preferencial predominante das anomalias foi NE-SW e uma orientação subsidiária de direção NW-SE, o que sugeriu um controle estrutural sobre a ocorrência de diques e/ou soleiras, sob os altos gravimétricos. Em Chico Lomã a ocorrência de uma extensa anomalia Bouguer positiva formando um trend de orientação NE-SW foi correlacionada a unidades geológicas da Planície Costeira do Rio Grande do Sul: altos gravimétricos caracterizaram a Barreira I e baixos gravimétricos, os Sistemas Lagunares I e II. O método gravimétrico se mostrou eficaz para a caracterização da jazida por meio da correlação de anomalias gravimétricas positivas com as ocorrências de diabásio. / The present dissertation was developed according to standard 103 of the Graduate Program in Geosciences of the Federal University of Rio Grande do Sul, which provides for the submission of the dissertation in the form of article, predates by state of the art proposed theme. In the southeastern region of the Paraná Basin are located economically important coal deposits in the states of Parana, Santa Catarina and Rio Grande do Sul. These deposits are often much altered by volcanic intrusions. The objective of this study is to map the igneous intrusions affecting the thermal change of level of coal (rank) of the coal deposit Morungava-Chico Lomã in RS. The coal deposit Morungava-Chico Lomã was discovered in the last century and has never been mining. It is characterized by organic rocks of the Permian, coal and bituminous shale, in the southern portion of the Paraná Basin. The gravimetric acquisition was carried in área of the deposit Morungava and in the area of the deposit Chico-Lomã. For both areas the choice of acquisition locations was based on previously conducted drilling holes. With data from the holes drilling were prepared these thematic maps: depth of the first occurrence of coal; cumulative thickness of coal; depth of the first occurrence of diabase; cumulative thickness of diabase; cumulative thickness of diabase in Irati Formation and cumulative thickness of the diabase in Rio Bonito Formation. In the elaboration of article submitted the overriding of the isolines of cumulative thickness of coal and diabase in the filtered Bouguer anomaly maps was performed. These overrides presented correlations and assisted in the interpretation of gravity data. The predominant preferential orientation of the anomalies was NE-SW and a subsidiary orientation NW-SE direction, suggesting a structural control on the occurrence of dikes and/or sills, on gravimetric high. In Chico Lomã the occurrence of an extensive positive Bouguer anomaly forming a trend of NE-SW orientation was correlated with geological units of Rio Grande do Sul Coastal Plain: gravimetric characterized the high Barrier I and low gravimetric, Systems Lagunar I and II. The gravimetric method proved efficient for the characterization of the deposit through the correlation of positive gravity anomalies with occurrences of diabase.
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Petrografia e geoquímica das rochas intrusivas básicas da porção sudeste do Cinturão Dom Feliciano, RSBarbosa, Laércio Dal Olmo January 2017 (has links)
A participação de líquidos magmáticos extraídos do manto, registrados sob a forma de intrusões dioríticas, gabroicas e de rochas máficas-ultramáficas, tem sido apontada como uma componente determinante na geração de magmas intermediários a ácidos, em ambientes orogênicos a pós-colisionais. Neste contexto, a colocação de líquidos basálticos hidratados na base da crosta também é considerada um importante marcador petrogenético, já que além de fornecer calor, pode ainda contribuir com líquidos residuais fracionados, essenciais à geração de magmas evoluídos. Além disso, magmas pouco diferenciados podem igualmente ascender e atingir níveis superiores da crosta, interagindo com câmaras magmáticas silicosas. Assim, estas rochas acabam por registrar tanto os processos de extração e transporte de magmas do manto, resultando na acresção vertical de material à crosta, quanto os processos de interação entre esses dois componentes. Na porção sudeste do Cinturão Dom Feliciano (RS), constituída majoritariamente por granitoides, ocorrem rochas dioríticas e gabroicas de extensão reduzida (1 a 7 km) e caráter dominantemente básico, na região compreendida entre os municípios de Pinheiro Machado e Pedro Osório. Nesta dissertação, por meio da caracterização geológica, mineralógica, petrográfica e geoquímica destas rochas, propõe-se a separação de duas associações principais. A “Associação I” (AI) engloba os corpos do Passo da Fabiana, Passo da Olaria, Arroio Santa Fé e Desvio Herval, constituindo-se por rochas gabroicas comumente cumuladas, por vezes estratificadas A “Associação II” (AII), diorítica a gabroica, compreende rochas isótropas a localmente foliadas, nas ocorrências do Alto Alegre, Passo dos Machados e Campo Bonito. As duas associações são subalcalinas, com afinidade cálcio-alcalina médio-K (AI) e médio a alto-K (AII), exibindo altos teores de alumina (Al2O3 > 17%), mesmo para os termos não cumulados. Maiores valores de CaO e Mg# na AI, e de álcalis, P2O5, Zr, Nb, Y, e total de ETR na AII, bem como padrões distintos de ETR, referendam a separação das associações. O controle no posicionamento das rochas básicas por descontinuidades litosféricas é sugerido pelas assinaturas magnéticas, que teriam possibilitado a ascensão e colocação destes magmas em níveis superiores da crosta. Como processos petrogenéticos, sugere-se a participação de líquidos derivados do manto em câmaras magmáticas supracrustais, seja como pulsos precursores do magmatismo associado aos granitoides, ou por eventos de reabastecimento destes reservatórios, como predominantes na AI. Já na AII, rica em anfibólio, processos envolvendo a colocação e evolução de magmas do manto nas DCHZ (deep crustal hot zones), originando líquidos hidratados, parecem ser mais expressivos. / The participation of mantle-derived melts, recorded as dioritic, gabbroic and mafic-ultramafic rocks, has been identified as a determinant component in the generation of intermediate to acid magmas, in orogenic to post-collisional settings. In this context, the emplacement of hydrous basaltic liquids at the base of the crust is also considered an important petrogenetic marker, not only providing heat, but also producing residual fractionated liquids, essential to the generation of evolved magmas. Furthermore, less differentiated magmas can also ascend and reach upper crustal levels, interacting with silicic magma chambers. Therefore, this rocks record both magma extraction and transport processes from the mantle, resulting in vertical material accretion to the crust, as well as the interaction between these two components. In the southeastern portion of Dom Feliciano Belt (RS), which is composed mainly by granitoids, minor dioritic and gabbroic rocks occur (1 to 7 km), with predominantly basic character, in the region between Pinheiro Machado and Pedro Osório. This thesis presents geological, mineralogical, petrographic and geochemical characterization of these rocks, proposing thus the separation of two main associations. The "Association I" (AI) comprises the bodies Passo da Fabiana, Passo do Olaria, Arroio Santa Fé and Desvio Herval, and is composed by gabbroic rocks, commonly as cumulates, sometimes in layered intrusions The "Association II" (AII), dioritic to gabbroic, comprises isotropic to locally foliated rocks, in the occurrences of Alto Alegre, Passo dos Machados and Campo Bonito. Both associations are subalkaline, with medium-K (AI) and medium to high-K (AII) calc-alkaline affinity, showing high-alumina contents (Al2O3 > 17%), even for the non-cumulated terms. Higher CaO and Mg# values in AI, and alkalis, P2O5, Zr, Nb, Y, and total REE in AII, as well as distinct REE patterns, support the proposed associations. The control on the emplacement of the basic rocks by lithospheric discontinuities is suggested by magnetic signatures, which would have enabled the ascent and emplacement of these magmas to upper crustal levels. As petrogenetic processes, the participation of mantle-derived liquids in supracrustal magma chambers is suggested, either as precursor pulses of the magmatism associated with the granitoids, or by replenishment events in these reservoirs, as prevalent in AI. In the AII, amphibole-rich, processes involving the emplacement and evolution of mantle-derived magmas in DCHZ (deep crustal hot zones), originating hydrous liquids, seems to be more expressive.
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Sacred ceremony and magical praxis in Jewish texts of early and late antiquityBloom, Miriam January 1999 (has links)
The thesis examines texts that indicate how Jews of Early and Late Antiquity dealt with a world ruled by an omnipotent God who governed a cosmos where disorder vied with order. God's bounty reflected his good will towards those faithful to his laws, and disobedience resulted in the infliction of misfortune. A state of disorder, labelled “the ways of the Emorites”, was perceived by Judaeans as the realm of superstition and foreign practices, typified by idolatry, incest and bloodshed. Sacrifice in the Temple allowed people to fulfil God's commandments, drawing near to him by means of animal or cereal offerings. When the Temple was destroyed, prayer rituals replaced the sacrifices. The absence of priestly authority allowed Rabbis to take control of everyday religious laws and customs. Concepts such as the sacred and mundane, and ritual purity and impurity, are integral to the scriptural texts. Later texts retained paradoxical notions relating to these older traditions concerning ambiguity or ambivalence associated with purification and pollution, and these notions remained within the ambit of the rabbinic purview. The transformation of public sacrifice into communal prayer was accompanied by aspirations to draw near to God, no longer simply as an act of obedience, but to attain aspects of his wisdom and power. God was no longer present in his Temple, but had taken on the role of King of Heaven, seated upon his Throne in the celestial heights, and the power attained by some Rabbinic sages in mystical ascents enabled them to perform miraculous feats. Ideas of the sacrificial cult and notions of ritual purity retained their influence in prayers, and esoteric Rabbinic traditions were appropriated by exponents of private magical rituals. Angels and demons inhabited the Talmudic cosmology, and angelic forces summoned in God's name might control the misfortune resulting from demonic intrusions.
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Mafické a intermediální intruze jako průvodci peraluminických granitů krušnohorského batolitu / Mafic and intermediate intrusions accompanying peraluminious granites of the Krušné hory Mts.batholitHolečková, Pavla January 2012 (has links)
Mafic and intermediate intrusions commonly accompany Variscan granitoid plutons in Europe. They are documented from different localities of Iberian Peninsula, from the French Massif Central, Schwarzwald, from different parts of the Bohemian Massif, in Romania, Greece, Corsica and Sardinia. They comprise wide petrographic varieties from quartz gabbros, diorites, granodiorites to monzonites. They usually constitute small bodies or veins, they often occur as mafic microgranular enclaves (MME) in granodiorites and in some granites. Dioritic intrusions are characterized by a relatively high amounts of lithophile elements (Rb, Sr, Ba, Cs, LREE), and they are simultaneously high in compatible elements (Ni, Cr, V a Co). Their isotopic ratios 87 Sr/86 Sr are in all compared locations similar and are close to the Bulk Earth (0.704 - 0.708). εNd values show larger scatter, some intrusions have more crustal composition (to -8), on the other hand, another intrusions have εNd positive, that points to a contribution of basic magma. The age of dioritic intrusions differs according to individual locality suggesting more than one magmatic episode. The oldest occur in the French Massif Central (361 - 365 Ma), whereas the youngest are documented in Iberia (312 - 310 Ma). The oldest mafic intrusions in the Bohemian...
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Statistical and wavelet analysis of density and magnetic susceptibility data from the Bushveld Complex, South AfricaSepato, Obone January 2015 (has links)
A dissertation submitted to the Faculty of Science, University of the Witwatersrand, in fulfilment of the requirements for the degree of Master of Science.
Johannesburg, 2015 / The Bushveld Complex (BC) is the largest known layered intrusion. This suite of rock crop out in northern South Africa to form the Western, Eastern and Northern Limbs. Most research carried out focuses on the mineralized horizons in the Rustenburg Layered Suite (RLS) of the BC. This study presents a large database of wireline geophysical logs across a substantive part of the stratigraphy of the RLS. These consist of density and magnetic susceptibility datasets sampled at 1 cm. The major lithologies of the RLS intersected in the boreholes presented are gabbro, gabbronorite, norite and anorthosite whose density histograms reveal that they are predominantly normally distributed, with density averages of 2.86-2.91 g/cm3. The lithologies consist of mainly two minerals, pyroxene and plagioclase. In general, the average density increases with an increase in pyroxene. The distribution of the magnetic susceptibility for these lithologies has a large variation from SI to 13.2 SI, which is typical of layered intrusions. Susceptibility distributions are also multi-modal, asymmetric and not normally distributed, which makes the average magnetic susceptibilities less representative of the lithologies.
Cross-correlation plots between density and magnetic susceptibility for several boreholes show that the above-mentioned lithologies form clusters (circular to elliptical), which typically overlap. This has been further investigated using k-means classification, to automatically detect these clusters in the cross-correlation plots and to compare these with those created by lithologies. The comparison shows some degree of correlation, implying that physical properties can be used to identify lithologies. This is particularly true for the Eastern Limb. However the classification has not been effective in all of the boreholes and often becomes complicated and an inaccurate representation of lithology log. This occurs in boreholes in which there is an overlap in the physical properties of the abovementioned lithologies.
Analysis on the density and magnetic susceptibility data has also been carried out using wavelet analysis at individual locations across the BC. This has revealed multi-scale cyclicity in all of the boreholes studied, which is attributed to subtle layering created by variations in modal proportions between plagioclase and pyroxene. In addition to this, since layering is generally ubiquitous across layered intrusions, this cyclicity can be assumed to be present across the entire BC. This technique may become increasingly important should the cyclicity in physical property data correlate with reversals in fractionation trends since this may suggest zones of magma addition, whose thickness or
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volumes can be quantified using wavelet analysis. This could be an important contribution since the current perspective on magma addition in the RLS is that four major additions have formed this 8 km thick suite of rocks, as opposed to smaller periodic influxes of magma.
Wavelet-based semblance analysis has been used to compare the wavelengths at which the cyclicity occurs across boreholes. A comparison of wavelengths of this cyclicity shows that boreholes in the northern Western Limb show positive correlation in the density data at wavelengths >160 m and 20-60 m, while those further south show correlations at wavelengths of 120-200 m and 60-80 m. Boreholes of the Eastern Limb show positive correlation in the density and magnetic susceptibility data at wavelengths of 10-20 m, 20-30 m and 5m. These positive correlations across boreholes in density and magnetic susceptibility respectively, may imply that cyclicity may be produced by a chamber-wide process for several kilometres of the BC.
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Fractional crystallization and intrusion mechanisms, spur slice (Block 4), Cape Smith, New QuébecBédard, Jean H. January 1981 (has links)
No description available.
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Petrogenesis of the McGerrigle plutonic complex, Gaspe, QuebecWallace, Graeme M. B. January 1988 (has links)
No description available.
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