Volcanic Structures
Mostrando 13-16 de 16 artigos, teses e dissertações.
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13. Petrogenese das intrusões graniticas compostas de Teofilandia e Barrocas, Greenstone Belt do Rio Itapicuru, Bahia, Brasil
The Rio Itapicuru Greenstone Belt (RIGB) is a Paleoproteozoic sequence situated in the northern portion of the São Francisco Craton, Bahia state, Brazil. Overlying a basement consisting of gnaisse and migmatites, this volcanic-sedimentary belt is intruded by several granitoid intrusions of different chemical compositions. Two of the most important intrusive
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 26/08/2002
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14. Rochas metamorficas maficas e ultramaficas do Greenstone Belt Barbacena na região de Itutinga, MG
In the area around ltutinga-Nazareno, Minas Gerais State, at the southeastem limit of São Francisco Craton, there are outcrops of thick successions of volcanic mafic and ultramafic rocks that are the subbject of the present study. This volcano-sedimentary succession is mainly constituted by metabasalts, metakomatiites and minor metassedimentary rocks, and i
Publicado em: 2000
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15. 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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16. 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