Metasediments
Mostrando 13-16 de 16 artigos, teses e dissertações.
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13. Caracterização tectono-metamorfica do deposito aurifero Ambrosio, Greenstone Belt do Rio Itapicuru - Bahia
The Ambrósio lode gold deposit, located in the northem sector ofthe lower Proterozoic (2.200 to 2.000 Ma) Rio Itapicuru greenstone belt, northeast Brazil, is enclosed within a narrow belt ofhighly deformed supracrustals, tightly squeezed between two syn-tectonic granitic batholiths (pedra Alta and Ambrósio domes). The deposit is hosted at the contact of am
Publicado em: 1996
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14. Aspectos tectono-estruturais do "Greenstone Belt" de Piumhi, MG em relação a mineralização de cromita e ouro
The Piumhi greenstone belt of Archaean age in SW Minas Gerais State, Brazil, is located within the limits of the Tocantins and São Francisco provinces of Almeida et aI. (1981). This belt is made up of a lower volcanic sequence , the Ribeirão Araras Group, consisting of komatiites, tholeiites, acid and intermediate volcanic rocks, overlain by metasediments
Publicado em: 1996
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15. Evolução geologica do pre-cambriano da porção centro-leste da serra do Espigão meridional e metalogenese associada
A porção centro-leste da Serra do. Espinhaço Meridional é caracterizada principalmente por terrenos de idade Pré-Cambriana, incluindo seqüências do Arqueano (Complexo de Gouveia, de alto grau metamórfico, e Grupo Pedro Pereira, de baixo grau) e do Proterozóico (todas de baixo grau metamórfico: Grupo Costa Sena, Supergrupo Espinhaço "sensu stricto"
Publicado em: 1990
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16. Branched aliphatic alkanes with quaternary substituted carbon atoms in modern and ancient geologic samples
A pseudohomologous series of branched aliphatic alkanes with a quaternary substituted carbon atom (BAQCs, specifically 2,2-dimethylalkanes and 3,3- and 5,5-diethylalkanes) were identified in warm (65°C) deep-sea hydrothermal waters and Late Cretaceous black shales. 5,5-Diethylalkanes were also observed in modern and Holocene marine shelf sediments and in sh
National Academy of Sciences.