Epidote
Mostrando 1-12 de 16 artigos, teses e dissertações.
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1. Micro-structural and compositional variations of hydrothermal epidote-group minerals from a peralkaline granite, Corupá Pluton, Graciosa Province, South Brazil, and their petrological implications
Minerais do grupo do epidoto, com albita, quartzo, fluorita, filossilicatos pobres em Al e ricos em Fe, zircão e quantidades menores de óxidos e sulfetos são fases hidrotermais típicas em álcali-feldpato granitos peralcalinos do Pluton Corupá, Província Graciosa, Sul do Brasil. Os minerais do grupo do epidoto ocorrem como cristais individuais ou agreg
Anais da Academia Brasileira de Ciências. Publicado em: 26/04/2012
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2. Magmatic epidote and amphibole from the Rio Espinharas hybrid complex, Northeastern Brazil
The petrography and chemistry of epidote and amphibole from the Rio Espinharas hybrid complex (REHC), northeastern Brazil are reported. The Rio Espinharas complex is composed of an intimate association of diorite to shoshonitic metaluminous quartzmonzonite to slightly peraluminous syenogranite. The epidote shows four textural relationships: three are primary
Publicado em: 2010
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3. Geoquímica de rochas metabasálticas da mina da Palma, Bloco São Gabriel, escudo sul-rio-grandense: um possível platô oceânico
The Mina da Palma oceanic plateau is described for the first time in the São Gabriel Block, southern Brazilian Shield. It is composed mostly of metabasalts, marbles and metachert. Two deformational events are recognized in the Palma region, thrust faulting followed by dextral subvertical shearing. The rocks were metamorphosed in the greenschist facies, as s
Publicado em: 2010
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4. Áreas fontes dos minerais pesados e sua distribuição sobre a plataforma continental sul-brasileira, uruguaia e norte-argentina
The heavy mineral fraction of sedimentary rocks and sediments can provide important information about provenance in sedimentary basins studies because some minerals or group of minerals can be traced to a source rock or terrain of specific composition. This work is a provenance study based on heavy mineral analyses of samples collected on the Rio Grande do S
Publicado em: 2010
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5. Inclusões fluidas nos minerais associados a mineralização uranífera da jazida do Engenho (anomalia 09), Província Uranífea de Lagoa Real, Bahia / Fluid Inclusions in minerals associated to uranium mineralization in Engenho Deposit (anomaly 09) Lagoa Real Uranium Province Bahia
The Engenho deposit (anomaly 09) is south-eastern from Cachoeira Mine (anomaly 13), in the northern part of the Province. The uranium mineralization is associated to albitites (over 70% of albite/oligoclase). Epidosites with uranium may also occur. The albitite main minerals are pyroxene, garnet, albite/oligoclase feldspar, amphibole and biotite. Pyroxene, g
Publicado em: 2009
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6. Características epigenéticas do depósito de cu-au chapada, arco magmático de goiás
The Cu-Au Chapada deposit is located from 8km of Alto Horizonte-GO. The geologic picture is dominated by metavulcanic sedimentary sequences that integrate the Neoproterozoic Magmatic Arc of Mara Rosa, located in the central portion of the Tocantins Province. The framework of the deposit is represented by an antiform whose core is composed by association of t
Publicado em: 2009
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7. Datação química U-Th-Pb de minerais dos albitidos uraniferos da região de Lagoa Real (BA) por microssonda eletrônica
Different works in literature have used U-Th-Pb electron microprobe analyses for the chemical dating of U-Th-Pb system closing episodes in minerals. These episodes could have either metamorphic, thermal, and weathering nature or could be related to natural fission processes. Different thorium and uranium-bearing minerals which contain radiogenic lead have be
Publicado em: 2008
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8. Petrologia e metalogenia do Depósito de Cobre Bom Jardim de Goiás (GO)
The Bom Jardim de Goiás Deposit is located at western Goiás State, on the western border of the Arenópolis magmatic arc. A reserve of 4,575,660 t, containing 0,92% Cu, was estimated by Serviço Geológico do Brasil (CPRM). The country rocks comprise vulcanoclastic rocks assigned to the Córrego da Aldeia formation from the Bom Jardim de Goiás Group, with
Publicado em: 2007
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9. Analise de traços de fissão em epidoto : obtenção de idades e estudo de annealing / Epidote fission-track analysis : age obtention and annealing experiments
Epidote fission-track ages for samples from the Serra da Mantiqueira were obtaine via both Population an External Detector Methods (EDM) an the mean value was (201 ± 15) Ma. The ages showe internal consistency an are place between those obtained through apatite, (127 ± 10) Ma, and the zircon fission-track dating, (369 ± 15) Ma. Studies concerning the epid
Publicado em: 2005
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10. Oxygen isotopes internal equilibrium in magmatic epidote-bearing granitoids
Anais da Academia Brasileira de Ciências. Publicado em: 2002-09
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11. Estudo da datação por traços de fissão em epídoto
Epidote is a mineral with promising applications in the Fission Tracks Method (FTM). Among them, can be stressed his formation in fault zones and his high closure temperature compared with the better studied mineral, the apatite. In the 1970´s, the fission-track community turned the attention to epidote but abandoned it in the next decade due to difficultie
Publicado em: 2002
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12. Ion microprobe (SHRIMP) dates complex granulite from Santa Catarina, southern Brazil
Complex polymetamorphic granulites have been dated in the Santa Catarina granulite complex of southern Brazil through SHRIMP study of zircon. This complex is dominated by intermediate-acid plutonic rocks and contains small volumes of mafic and ultramafic rocks, and minor quartzite and banded iron formation. Porphyroblasts of orthopyroxene, clinopyroxene and
Anais da Academia Brasileira de Ciências. Publicado em: 2000-12