Manioc : Portail | resultats 81 - 100 pour la recherche: Silva, J. M. R.

Fleuves de l'Amérique du sud :1877-1879. Missions du ministère de l'instruction publique
Auteur(s) : Crevaux, Jules (1847-1883)
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Six months in the West Indies, in 1825
Auteur(s) : Coleridge, Henry Nelson (1798-1843)
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Flora brasiliensis : enumeratio plantarum in Brasilia hactenus detectarum quas suis aliorumque botanicorum studiis descriptas et methodo naturali digestas partim icone illustratas. Volumen IV, Pars II
Auteur(s) : Eichler, August Wilhelm (1837-1887) Masters, Maxwell Tylden (1833-1907) Solms-Laubach, Hermann zu (1842-1915) Caspary, Robert (1814-1887) Schumann, Karl (1851-1904)
Auteurs secondaires : Martius, Karl Friedrich Philipp von (1794-1868)
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Ensaio corografico sobre a provincia do Para
Auteur(s) : Baena, Antonio Ladislau Monteiro (1782-1850)
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Guyane indépendante
Auteur(s) : Cook, Auguste
Auteurs secondaires : Hays, Samuel
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Faits relatifs à la traite des Noirs
Auteur(s) : Société de la morale chrétienne (France). Comité pour l'abolition de la traite des noirs
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U-Pb ages of plutonic and metaplutonic rocks in southern Borborema Province (NE Brazil): Timing of Brasiliano deformation and magmatism
Auteur(s) : Neves, S. P. Bruguier, Olivier Bosch, Delphine Silva, J. M. R. Mariano, G.
Auteurs secondaires : Departamento de Geologia, Universidade Federal de Pernambuco, Recife ; Université du Québec Géosciences Montpellier ; Université des Antilles et de la Guyane (UAG) - Institut national des sciences de l'Univers (INSU - CNRS) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS)

Éditeur(s) : HAL CCSD Elsevier
Résumé : International audience
The Borborema Province of northeastern Brazil is divided into three main domains: northern, central, and southern. Several U-Pb zircon ages of plutons and orthogneisses became available in the recent years in the central and northern domains, but similar results are scarce in the southern domain. This study reports U-Pb dates for single zircon grains from one orthogneiss (Jupi orthogneiss) and two plutons (Cachoeirinha syenitic pluton and Cabanas granite) south of the East Pernambuco shear zone system (EPSZ). The results provide geochronological constraints on the timing of deformation and magmatism in this part of the southern domain and allow correlations with the central domain. The Jupi orthogneiss was emplaced and deformed during development of the regional flat-lying foliation. A Pb-206/U-238 weighted apparent mean age of 606 +/- 8 Ma is interpreted as the crystallization age of the protolith of the orthogneiss and consequently the age of high-grade Brasiliano metamorphism. The NNE-trending Cachoeirinha pluton is only locally affected by strike-slip deformation, whereas the ENE-trending Cabanas granite is intensely affected by deformation related to the EPSZ. The 587 8 Ma and 573 4 Ma ages of the Cachoeirinha pluton and Cabanas granite, respectively, bracket the main period of activity of the EPSZ. Tectonomagmatic activity in the study area is similar to the age of Brasiliano events in the central domain, north of the EPSZ. In addition, xenocrystic zircons in the Jupi orthogneiss and Cabanas granite are interpreted as inherited from Paleoproterozoic source rocks, suggesting the presence of widespread reworked old crust in the southern domain, similar to the central domain. These results support the idea that the central and southern domains belonged to the same crustal block before the onset of the Brasiliano orogeny.
ISSN: 0895-9811

hal-00411394
https://hal.archives-ouvertes.fr/hal-00411394
DOI : 10.1016/j.jsames.2007.06.003

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