Ophiolite
Mostrando 1-8 de 8 artigos, teses e dissertações.
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1. Petrologia e geocronologia do complexo máfico-ultramáfico trincheira, sudoeste do cráton amazônico: implicações tectônicas do mesoproterozóico
The tectonic framework of the ultramafic-mafic rocks of the southwestern Amazon Craton is generally little known. Most of work this cratonic portion is focused on the geochronological studies of granitoids, so that little is known about the origin and tectonic significance of these rocks. In this context, this study contributes to the knowledge of the tecton
IBICT - Instituto Brasileiro de Informação em Ciência e Tecnologia. Publicado em: 2012
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2. Geoquímica e isótopos de Nd de rochas metavulcânicas da antiforme Capané, complexo metamórfico Porongos, RS
The Capané Antiform, located in the northern part of the Neoproterozoic Porongos Metamorphic Complex (RS), is composed of a supracrustal sequence metamorphosed under greenschist (eastern flank) to amphibolite (western flank) facies. Four groups of rocks were recognized. Groups 1 and 2 are constituted of felsic and mafic rocks from the central and western pa
Publicado em: 2010
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3. Complexo ofiolítico Quatipuru, Pará, Brasil
Os tratos oceânicos existentes entre os blocos continentais descendentes do supercontinente Rodínia são registrados na Faixa Araguaia por meio de corpos ofiolíticos. Tais corpos frequentemente não apresentam a clássica pseudo-estratigrafia de ofiolitos, sendo representados principalmente por peridotitos mantélicos serpentinizados e derrames basáltico
Publicado em: 2009
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4. Mid amphibolite facies metamorphism of harzburgites in the Neoproterozoic Cerro Mantiqueiras Ophiolite, southernmost Brazil
O estudo integrado de relações geológicas, micro-estruturais e composição química de minerais resultou na obtenção de informações muito valiosas sobre a evolução dos harzburgitos do Ofiolito Cerro Mantiqueiras, de idade Neoproterozóica. Este importante marcador geotectônico da evolução geológica do extremo sul do Escudo Brasileiro foi serpen
Anais da Academia Brasileira de Ciências. Publicado em: 2003-03
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5. Caracterização metalogenetica do deposito cromotiferos de Pedras Pretas, Santa Luz - BA
The chromitiferous mineralization of Pedras Pretas Intrusive Suite, Bahia, Brazil, is host in serpentinites intrusive into meta-sedimentary and meta-igneous rocks comparable to the 2.2-2.0 Ga old Itapicuru River Greenstone Belt. Field relationships and petrographic data indicate that the study area has undergone four major deformation phases with metamorphic
Publicado em: 1998
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6. 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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7. Caracterização da "Zona de Sutura" Jacui-Conceição da Aparecida, MG - limite norte do Cinturão Alto Rio Grande : im plicações geotectonicas e metalogeneticas
An are a in the Southwest of Minas Gerais, including the town of Petúnia, was divided into two distinct terrains, namely, Campos Gerais Belt and Petúnia Complex, both collectively called Campos Gerais Complex in earlier works. The former, and older, is an autochtonous terrain regarded as the basement to the latter. It is located in the northern part of the
Publicado em: 1993
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8. High-pressure highly reduced nitrides and oxides from chromitite of a Tibetan ophiolite
The deepest rocks known from within Earth are fragments of normal mantle (≈400 km) and metamorphosed sediments (≈350 km), both found exhumed in continental collision terranes. Here, we report fragments of a highly reduced deep mantle environment from at least 300 km, perhaps very much more, extracted from chromite of a Tibetan ophiolite. The sample consi
National Academy of Sciences.