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Στην εργασία αυτή παρατίθενται γεωλογικά, τεκτονικά και γεωχημικά στοιχεία για την ευρύτερη περιοχή της πόλης Gaspe αλλά και πιο συγκεκριμένα του δόμου Lemieux. Τα στοιχεία αυτά έχουν συλλεχθεί με την μέθοδο PIMA, της οποίας και αναφέρεται η χρησιμότητα, η λειτουργία και η καινοτομία. Με βάση αυτά τα στοιχεία καθώς και με την βοήθεια του προγράμματος mapinfo δίνονται χάρτες της περιοχής μελέτης με τις συγκεντρώσεις των σημαντικότερων στοιχείων, ώστε να οδηγηθούμε στα απαραίτητα συμπεράσματα σχετικά με την κοιτασματολογία του δόμου καθώς και με τις πιθανές θέσεις μεταλλοφορίας. / In this paper geological, tectonic and geochemical data are presented for the region of Gaspe town and more specifically for the Lemieux Dome. These data were collected using the PIMA method, of which are indicated the usefulness, functionality and innovation. On this basis and with the help of the given mapinfo maps of major element's concentrations of the exploration area, we are led to the necessary conclusions on the mineralogy of the dome and the possible drilling targets.

Orientador: Daniel Marcos Bonotto / Banca: Francisco Yukio Hiodo / Banca: Wanilson Luiz Silva / Banca: Rosemarie Rohn Davis / Banca: Antônio Carlos Artur / Resumo: O gás radônio, resultado do decaimento radioativo do 238U e 232Th, é motivo de grande preocupação para o homem. Ele é uma das mais importantes fontes de radiação ionizante de origem natural que as pessoas estão expostas, sendo considerado pela OMS (Organização Mundial da Saúde) como o segundo maior causador de câncer de pulmão. O carvão mineral como qualquer outro combustível fóssil está associado a materiais radioativos naturais, devido principalmente ao seu conteúdo de 238U e 232Th. Para a compreensão do comportamento do gás radônio em área de mineração de carvão e determinar o grau de exposição das pessoas ao gás nesta área, foram determinadas a taxa de exalação de radônio de amostras de carvão, cinza, siltito e tufo vulcânico coletadas na mina Amado Simões PI-08 (Companhia Carbonífera do Cambuí), em Figueira (PR), a concentração de radônio no ar do interior da mina e a concentração de radônio, parâmetros físicos e químicos dos solos próximos à mina. As taxas de exalações foram obtidas por curvas experimentais da concentração de radônio em função do tempo, e variaram de 0,064 a 0,717 Bq/kg.h. Observou-se que o gás radônio entrou em equilíbrio radioativo após 180 horas de análise. A concentrações de radônio dissolvido no ar do interior da mina variaram de 7,2 a 770,5 Bq/m³, observou-se que o radônio tem maior escape das rochas por fraturas presentes nas frentes de lavra e que maior taxa de exalação vem das rochas encaixantes, remetendo em um problema radiológico à área de d... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: Radon gas, the result of the radioactive decay of 238U and 232Th, is a matter of great concern to man. It is one of the most important sources of naturally occurring ionizing radiation that people are exposed to and is considered by the World Health Organization (WHO) to be the second largest cause of lung cancer. Mineral coal like any other fossil fuel is associated with natural radioactive materials, mainly due to its content of 238U and 232Th. In order to understand the behavior of the radon gas in the coal mining area and determine the degree of exposure of the people to the gas in this area, the radon exhalation rate of samples of coal, ash, silt, and volcanic tuff collected at the Amado mine Simões PI-08 (Companhia Carbonífera do Cambuí), in Figueira (PR), the radon concentration in the air inside the mine and the radon concentration, physical and chemical parameters of the soils near the mine. The exhalation rates were obtained by experimental curves of the radon concentration as a function of time, and ranged from 0.064 to 0.717 Bq / kg.h. It was observed that the radon gas entered into radioactive equilibrium after 180 hours of analysis. The concentrations of radon dissolved in the air inside the mine varied from 7.2 to 770.5 Bq / m³, it was observed that the radon has greater escape of the rocks by fractures present in the mining fronts and that higher exhalation rate comes from encasing rocks, sending in a radiological problem to the area of discard. The concentrat... (Complete abstract click electronic access below) / Mestre

Intense interest in uranium in the past decade has led to the discovery of new kinds of deposits of which the so-called unconformity-type are economically the most important. Presently known occurrences are restricted to Australia and Canada where they are characterized chiefly by their spatial relationship to Lower-Middle Proterozoic unconformities. Other common features include similar host-rock assemblages, structural controls, alteration, mineralogy, age relationships and fluid-inclusion data. Similar characteristics in other vein-type deposits, including those of the Beaverlodge district in Canada, deposits in France and Portugal, and the Schwartzwalder mine in the United States, suggest that they may also be of the unconformity-type. Various interpretations of the geological relationships of unconformity-type deposits have resulted in a number of genetic hypotheses, which require different exploration philosophies. Nearsurface supergene processes are considered to be most important although other mechanisms may have played contributing roles in the concentration of uranium. There is considerable potential for further discoveries of unconformity-type uranium deposits throughout the world. No such deposits are yet known in southern Africa although several favourable Precambrian unconformities are present.

This thesis deals with fluid inclusion study of quartz samples from Ratibořské Hory and Stará Vožice and baryte samples from Stříbrná Skalice and Černé Voděrady. Samples were studied by methods of microthermometry of fluid inclusions, Raman spectrometry, UV-fluorescence spectrometry and EDX analysis. In quartz sample from Stará Vožice there were detected low-salinity H2O-CO2-N2 fluids that were trapped at min. 240 MPa and 260 řC. This mineralization is probably connected with initial stages of structural evolution of the Blanice Graben. Late-metamorphic fluids were probable source of these solutions. In sample of quartz containing grains of galena there were trapped mesothermal (Th = 110-195 řC) low- to medium-salinity H2O-NaCl fluids, hydrocarbon fluids and low- salinity (H2O)-CO2-N2-CH4 fluids (containing max. 13 mol. % N2+CH4 in carbonic phase) trapped at low pressure (max. 10 MPa) and relatively low temperature (105-120 řC). In Ratibořské Hory there were detected heterogeneously trapped low- to medium-salinity H2O±CO2±N2±CH4- NaCl±KCl±MgCl2±FeCl2 (with max. 26 mol. % N2+CH4 in carbonic phase) fluids trapped at 1-25 MPa and 160-315 řC. In barite sample from Černé Voděrady were detected low- to high-salinity aqueous fluids with Na and Ca ± K, Fe, Mg chlorides. These solutions are probably derived...

Made available in DSpace on 2014-06-11T19:26:14Z (GMT). No. of bitstreams: 0 Previous issue date: 2012-06-15Bitstream added on 2014-06-13T18:54:23Z : No. of bitstreams: 1 dias_cat_me_rcla.pdf: 1344683 bytes, checksum: 1acaaa814f2b0f234d70b3f93d51ba24 (MD5) / Coordenação de Aperfeiçoamento de Pessoal de Nível Superior (CAPES) / A mina Bom Futuro é atualmente uma das maiores produtora de estanho do país, com uma produção média anual nos últimos 10 anos de cerca de 2400 toneladas de estanho. As atividades industriais de extração de cassiterita na mina se concentram no morro Bom Futuro e adjacências, em depósitos primários e secundários, respectivamente. No morro Bom Futuro são reconhecidos dois pipes brechados alojados em gnaisses e anfibolitos, que são cortados por diques radiais e anelares de pórfiros graníticos com topázio, os quais são incluídos na Suíte Intrusiva Granitos Últimos de Rondônia (998 a 974 Ma). Pelo menos duas fases distintas de mineralização primária de estanho são identificadas com idades 40Ar/39Ar em zinnwaldita de 994±3 Ma e 993±3 Ma e são representadas por lentes, veios e vênulas de pegmatito e de quartzo. O pegmatito estudado ocorre na porção nordeste do morro, onde aparece hospedado em brechas de pipe e dique de topázio riólito pórfiro e cortado por dique de topázio granito pórfiro. Trata-se de um dique com mais de 200 m de comprimento, espessura variando 3 a 12 metros e de atitude geral N20E/45°SE. Na seção estudada com detalhe, o pegmatito mostra um zoneamento interno bem distinto, dado por camadas ou leitos subconcordantes entre si e com as paredes do dique. Pelo menos três zonas foram reconhecidas com base na mineralogia dominante, são elas do muro ao teto: zona do quartzo e topázio, zona do feldspato potássico e mica, e zona granítica (quartzo e feldspato potássico). Uma provável quarta zona não foi observada, mas segundo os garimpeiros, um leito de até 10 cm de espessura de cassiterita maciça ocorre de modo descontínuo junto ao muro do corpo. A estrutura das zonas é maciça e a granulação varia de média a grossa na zona granítica para grossa a muito grossa ou gigante (?) nas outras... / The mine Bom Futuro is currently one of the largest tin producer in the country with an average annual production over the past 10 years around 2400 tonnes of tin. The extraction industrial activities of cassiterite concentrate on the hill Bom Futuro and surrounding areas in primary and secondary deposits, respectively. On the hill Bom Futuro two breccia pipes are recognized hosted in gneisses and amphibolites, which are cut by radial and ring dikes of granite porphyry with topaz, which are included in the Intrusive Suite Latest Granites of Rondônia (998-974 Ma). At least two distinct phases of primary tin mineralization are identified with zinnwaldita 40Ar/39Ar ages of 994 ± 3 Ma and 993 ± 3 Ma and is represented by lenses, veins and venules of quartz and pegmatite. The studied pegmatite occurs in the northeastern portion of the hill, where it appears hosted in breccias pipe and topaz rhyolite porphyry dike cut by topaz granite porphyry dike. It is a dike over 200 meters in length, thickness ranging 3-12 meters and general attitude N20E/45 ° SE. In the studied section in detail, the pegmatite shows a very distinct internal zoning, given by layers or beds sub concordant among themselves and with the walls of the dike. At least three zones were recognized based on the dominant mineralogy, they are from the wall to the ceiling: zone of quartz and topaz, zone of mica and feldspar, and granitic zone (quartz and feldspar).A possible fourth zone was not observed, but according to the miners, a bed with 10 cm thick of massive cassiterite occurs discontinuously along the wall of the body. The structure of the zones are massive and the granulation varies from medium to coarse in the granite zone and coarse to very coarse or giant (?) In the other two. The primary mineralogy is relatively simple: the quartz is gray to milky white, the... (Complete abstract click electronic access below)

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Orientador: Washington Barbosa Leite Jr / Banca: Sebastião Gomes de Carvalho / Banca: César D'Abronzo Martinelli / Resumo: A mina Bom Futuro é atualmente uma das maiores produtora de estanho do país, com uma produção média anual nos últimos 10 anos de cerca de 2400 toneladas de estanho. As atividades industriais de extração de cassiterita na mina se concentram no morro Bom Futuro e adjacências, em depósitos primários e secundários, respectivamente. No morro Bom Futuro são reconhecidos dois pipes brechados alojados em gnaisses e anfibolitos, que são cortados por diques radiais e anelares de pórfiros graníticos com topázio, os quais são incluídos na Suíte Intrusiva Granitos Últimos de Rondônia (998 a 974 Ma). Pelo menos duas fases distintas de mineralização primária de estanho são identificadas com idades 40Ar/39Ar em zinnwaldita de 994±3 Ma e 993±3 Ma e são representadas por lentes, veios e vênulas de pegmatito e de quartzo. O pegmatito estudado ocorre na porção nordeste do morro, onde aparece hospedado em brechas de pipe e dique de topázio riólito pórfiro e cortado por dique de topázio granito pórfiro. Trata-se de um dique com mais de 200 m de comprimento, espessura variando 3 a 12 metros e de atitude geral N20E/45°SE. Na seção estudada com detalhe, o pegmatito mostra um zoneamento interno bem distinto, dado por camadas ou leitos subconcordantes entre si e com as paredes do dique. Pelo menos três zonas foram reconhecidas com base na mineralogia dominante, são elas do muro ao teto: zona do quartzo e topázio, zona do feldspato potássico e mica, e zona granítica (quartzo e feldspato potássico). Uma provável quarta zona não foi observada, mas segundo os garimpeiros, um leito de até 10 cm de espessura de cassiterita maciça ocorre de modo descontínuo junto ao muro do corpo. A estrutura das zonas é maciça e a granulação varia de média a grossa na zona granítica para grossa a muito grossa ou gigante (?) nas outras... (Resumo completo, clicar acesso eletrônico abaixo) / Abstract: The mine Bom Futuro is currently one of the largest tin producer in the country with an average annual production over the past 10 years around 2400 tonnes of tin. The extraction industrial activities of cassiterite concentrate on the hill Bom Futuro and surrounding areas in primary and secondary deposits, respectively. On the hill Bom Futuro two breccia pipes are recognized hosted in gneisses and amphibolites, which are cut by radial and ring dikes of granite porphyry with topaz, which are included in the Intrusive Suite Latest Granites of Rondônia (998-974 Ma). At least two distinct phases of primary tin mineralization are identified with zinnwaldita 40Ar/39Ar ages of 994 ± 3 Ma and 993 ± 3 Ma and is represented by lenses, veins and venules of quartz and pegmatite. The studied pegmatite occurs in the northeastern portion of the hill, where it appears hosted in breccias pipe and topaz rhyolite porphyry dike cut by topaz granite porphyry dike. It is a dike over 200 meters in length, thickness ranging 3-12 meters and general attitude N20E/45 ° SE. In the studied section in detail, the pegmatite shows a very distinct internal zoning, given by layers or beds sub concordant among themselves and with the walls of the dike. At least three zones were recognized based on the dominant mineralogy, they are from the wall to the ceiling: zone of quartz and topaz, zone of mica and feldspar, and granitic zone (quartz and feldspar).A possible fourth zone was not observed, but according to the miners, a bed with 10 cm thick of massive cassiterite occurs discontinuously along the wall of the body. The structure of the zones are massive and the granulation varies from medium to coarse in the granite zone and coarse to very coarse or giant (?) In the other two. The primary mineralogy is relatively simple: the quartz is gray to milky white, the... (Complete abstract click electronic access below) / Mestre

Made available in DSpace on 2014-10-09T12:24:13Z (GMT). No. of bitstreams: 0 / Made available in DSpace on 2014-10-09T14:07:12Z (GMT). No. of bitstreams: 1 01038.pdf: 2373326 bytes, checksum: 6700d091a3c179334b03259e2a632223 (MD5) / Dissertacao (Mestrado) / IEA/D / Escola Politecnica, Universidade de Sao Paulo - POLI/USP

Abstract Recent sea floor sulfide deposits form when seawater, heated within the oceanic crust, discharges to the sea floor. Upon mixing with cold seawater, sulfide-forming elements such as sulfur, iron, copper, and zinc are precipitated from the fluid. Actively forming sea floor massive sulfide deposits are found from different lithologic and tectonic environments varying from mid-ocean ridges to back-arc spreading centers. At a few localities, sulfide deposits are associated with turbiditic sediments that cover the axial valley of the spreading center. The southern part (Escanaba Trough) of the Gorda Ridge (NE Pacific) is one such example. At Escanaba Trough, massive sulfide deposits are associated with small sediment hills, which were uplifted by the intrusion of sills and laccoliths within the sediments. Hydrothermal deposits are dominated by pyrrhotite-rich massive sulfides, with subordinate amounts of sulfate-rich precipitates and polymetallic sulfides. Compared to deposits hosted by volcanites, Escanaba Trough sulfides contain relatively low amounts of copper and zinc. However, the average gold concentration is relatively high for a sediment-hosted deposit, and is comparable with other, Au-enriched, sea floor sulfide deposits. Despite the relatively high Au concentration in many volcanic-hosted sea floor sulfide deposits, discrete Au grains are rare. They occur mostly with sphalerite, pyrite, chalcopyrite and tetrahedrite-tennantite. Sixteen of the pyrrhotite-rich samples from Escanaba Trough were found to contain visible Au grains. They occur mostly with native Bi and various BiTe phases, and to lesser degree, with Fe-Co sulfarsenides. Transport of Au in sea floor hydrothermal systems is attributed to the presence of Au(HS)2- complex, which is destabilized when the fluid mixes with seawater. Hydrothermal fluids are generally undersaturated with respect to Au complexes and additional mechanisms, such as remobilizing earlier precipitated Au is required to explain the high Au concentrations encountered in many deposits. At Escanaba Trough the mechanism is attributed to early precipitation of Bi as melt droplets, at temperatures greater its melting temperature, as liquid Bi is capable of collecting Au even from an undersaturated fluid. Upon cooling Au is exsolved from the Bi host as native Au or maldonite (Au2Bi).