Monazite
Mostrando 1-12 de 20 artigos, teses e dissertações.
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1. Metamorphic modeling and petrochronology of metapelitic rocks from the Luminárias Nappe, southern Brasília belt (SE Brazil)
Abstract The Luminárias Nappe was formed in the agglutination of West Gondwana. A high-pressure metamorphic gradient oblique to the geological contacts is recorded in metapelitic rocks from this Nappe. In the northern portion, the metamorphic peak conditions are at high-pressure lower-amphibolite facies at 580 ± 4°C and ca. 0.9 GPa (Chl + Ky + St + Ms + Q
Braz. J. Geol.. Publicado em: 06/06/2019
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2. Electron microprobe Th-U-Pb monazite dating and metamorphic evolution of the Acaiaca Granulite Complex, Minas Gerais, Brazil
Abstract The Acaiaca Complex (AC) is located in southeastern Minas Gerais state, and comprises felsic, mafic, ultramafic, and aluminous granulites as well as lower grade gneisses and mylonites. The complex is distributed over an area of ca. 36 km by 6 km, surrounded by amphibolite facies gneisses of the Mantiqueira Complex (MC). The discrepancy in the metamo
Rem: Rev. Esc. Minas. Publicado em: 2016-03
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3. Thermobarometry and electron-microprobe Th-U-Pb monazite dating in garnet metapelites from the Capelinha Formation, Araçuaí Orogen, Brazil
Abstract The Capelinha Formation (Macaúbas Group) consists of a lower quartzitic unit with metamafic intercalations and an upper metapelitic sequence. It occurs in a complex tectono-metamorphic sector of the Araçuaí orogen, where post-collisional collapse-related structures superimposed collisional structures. The garnet-bearing assemblages started crysta
Rem: Rev. Esc. Minas. Publicado em: 2016-03
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4. Monazite ID-TIMS U-Pb geochronology in the LAGIR laboratory, Rio de Janeiro State University: protocols and first applications to the assembly of Gondwana supercontinent in SE-Brazil
Procedimentos químicos e espectrométricos do método geocronológico U-Pb em monazita, recentemente instalado no Laboratório LAGIR, são descritos em detalhe. Adicionalmente, resultados preliminares de amostras de monazita das faixas Brasília e Ribeira são relatados e discutidos no contexto geológico regional. Vários experimentos de calibração de co
An. Acad. Bras. Ciênc.. Publicado em: 2014-03
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5. Ocorrência e variabilidade de composição dos fosfatos do grupo monazita em carbonatitos
Monazite structural group includes arsenates, phosphates, and silicates, with general formulae A B O4 , (A = Bi, Ca, Rare Earth Elements, Th, U and B = As5+, P5+, Si4+). Among them, the phosphate monazite is the most abundant independent Rare Earth Element mineral, occurring in several geological sites. It presents a variable composition and morphology and h
Publicado em: 2010
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6. Avaliação da presença de monazita em concentrado de ilmenita produzido na mina do Guaju (PB)
A ilmenita é um mineral fonte de dióxido de titânio, matéria-prima utilizada como pigmento branco na fabricação de tintas e vernizes, principalmente. O concentrado de ilmenita, avaliado nesse estudo, provém da Mina do Guaju, no Estado da Paraíba, operada pela empresa Millennium Inorganic Chemicals do Brasil S/A. Esse concentrado contém monazita, que
Publicado em: 2010
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7. Evolução quimica e isotopica dos fluidos associados a mineralização de Fe-Cu-Au do deposito Alvo 118, provincia mineral de Carajas - PA / Chemical and isotopic evolution of the fluids from the Alvo 118 Fe-Cu-Au do deposit, Carajas mineral province (PA)
The Alvo 118 iron oxide-copper-gold (IOCG) deposit (170 Mt @ 1,0 wt% Cu, 0,3 g/t Au), together with the world-class Sossego and Cristalino deposits, lie in the southern sector of the Carajas Mineral Province (CMP) along a steeply-dipping, WNW-ESE-striking, 60 km-long shear zone, close to the contact of the Itacaiunas Supergroup metavolcano-sedimentary sequen
Publicado em: 2009
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8. Geology of high pressure granulites of Carvalhos Klippe, southern Brasília Belt / Geologia dos granulitos de alta pressão da Klippe Carvalhos, extensão sul da Faixa Brasília
At the top of Andrelândia Nappes System, southern border of São Francisco craton, occur nappes formed dominantly by metasedimentary rocks with subordinated metabasics and metaultramafics which record metamorphism of high pressure granulite facies in the Ediacaran. These nappes are Três Pontas - Varginha, Pouso Alto and Klippen Airuoca and Carvalhos. In Ca
Publicado em: 2009
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9. Geologia do Terreno Paranaguá / Geology of Paranaguá Terrane
The Paranaguá Terrane is composed of precambrian geological units distributed in a NE-SW elongated swath, about 250 km long and 30 km wide, in south-southeastern Brazil, within the States of São Paulo (Nothern Paranaguá Terrane), Paraná and Santa Catarina (Southern Paranaguá Terrane). This terrane is constituted mainly by an igneous complex, represented
Publicado em: 2009
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10. Geologia, geometalurgia, controles e gênese dos depósitos de fósforo, terras raras e titânio do complexo carbonatítico Catalão i , GO
This work describes the geological and geometallurgical characteristics of the phosphate, titanium, niobium and rare-earth elements deposits in the northeast part of the Catalão I carbonatite complex, Central Brazil. The mineralization controls were determined for magmatic, metasomatic and weathering processes. The ore types were defined on the basis of geo
Publicado em: 2008
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11. Fatores condicionantes na gênese dos argilominerais dos folhelhos negros e pelitos associados da formação Irati no norte da bacia do Paraná
The Permian Irati Formation has an extensive distribution in the Paraná basin, and is frequently intruded by diabase sills. The heterogeneous geometry of the basin in the depositional time propitiated the development of different sedimentary facies in this unit and favored the deposition of terrigenous rocks in the south portion of the basin and carbonate a
Publicado em: 2008
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12. Evolução de terrenos tectono-metamórficos da Serrania do Ribeira e Planalto Alto Turvo (SP, PR) / Evolution of tectono-metamorphic terranes of the Ribeira Ridge and Alto Turvo Plateau, SE Brazil
Numerous Precambrian terranes of enigmatic origin are recognized in the Ribeira Valley and Alto Turvo Plateau regions (Southeastern Brazil), based on contrasting evolutive histories and distinct lithotectonic, metamorphic and structural patterns. These suspect terranes form three major composite terranes juxtaposed during the late Brasiliano Cycle: Apiaí Te
Publicado em: 2008