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(Referência obtida automaticamente do Web of Science, por meio da informação sobre o financiamento pela FAPESP e o número do processo correspondente, incluída na publicação pelos autores.)

Timing of the HT/LP transpression in the Neoproterozoic Serido Belt (Borborema Province, Brazil): Constraints from U-Pb (SHRIMP) geochronology and implications for the connections between NE Brazil and West Africa

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Autor(es):
Archanjo, Carlos J. [1] ; Viegas, Luiz G. F. [1] ; Hollanda, Maria Helena B. M. [1] ; Souza, Laecio C. [2] ; Liu, Dunyi [3]
Número total de Autores: 5
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Inst Geociencias, BR-05508080 Sao Paulo - Brazil
[2] CCET UFRN, Dept Geol, BR-59000900 Natal, RN - Brazil
[3] Chinese Acad Geol Sci, Beijing SHRIMP Ctr, Beijing 10037 - Peoples R China
Número total de Afiliações: 3
Tipo de documento: Artigo Científico
Fonte: GONDWANA RESEARCH; v. 23, n. 2, SI, p. 701-714, MAR 2013.
Citações Web of Science: 33
Resumo

The Serido schist belt is a classical domain of the Borborema Province (NE Brazil) recording crustal melting at HT/LP conditions in a tectonic setting dominated by dextral transpressive deformation. A comparable tectonometamorphic setting has been described in the Pan-African Igarra and Ilesha schist belts of south Nigeria (Africa). The HT-transpression of the Serido has previously been imprecisely dated by using a range of isotopic methods on a suite of syntectonic granites. We provide new U-Pb zircon ages of the Acari granite and Santa Luzia migmatite that constrain the HT/LP metamorphism of the Serido at c. 575 Ma. Anisotropy of magnetic susceptibility of the Santa Luzia migmatite shows that the magnetic fabric records the NE-trending dextral kinematics similar to those previously described in the Acari pluton. On the other hand, the U-Pb ages of the Totoro pluton provide evidence for an older, mostly mafic to intermediate magmatism intruding the pelitic schist that precedes the HT/LP metamorphism by approximately 15 m.y. In contrast with the Acari pluton and Santa Luzia migmatite, the magnetic fabrics of Totoro show a concentric steep-dipping structure apparently related to magma ascent. Thermobarometric studies in the Serido, Igarra and Ilesha schist belts indicate that a large domain in the northern Borborema and south of the Nigeria shields was deformed at a high temperature and at relatively shallow depths. Although the tectonic setting for such a post-collision HT event remains an open issue, it allows us nevertheless to refine the across-Atlantic geological correlation between the continents. (C) 2012 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved. (AU)

Processo FAPESP: 09/17537-1 - Mecanismos de deformação e cronologia de eventos na zona de cisalhamento Patos, Província Borborema (Nordeste do Brasil)
Beneficiário:Luís Gustavo Ferreira Viegas
Linha de fomento: Bolsas no Brasil - Doutorado
Processo FAPESP: 10/50060-1 - Domos migmatiticos e milonitos do lineamento patos (provincia borborema, ne brasil): estudo estrutural e geocronologico dos eventos e alta temperatura.
Beneficiário:Carlos José Archanjo
Linha de fomento: Auxílio à Pesquisa - Regular