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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.)

Geology and geochronology of the Betara region in south-southeastern Brazil: Evidence for possible Statherian (1.80-1.75 Ga) and Calymmian (1.50-1.45 Ga) extension events

Texto completo
Autor(es):
Siga, Jr., Oswaldo [1] ; Cury, Leonardo Fadel [1] ; McReath, Ian [1] ; de Almeida Leite Ribeiro, Ligia Maria [1] ; Sato, Kei [1] ; Stipp Basei, Miguel Angelo [1] ; Passarelli, Claudia Regina [1]
Número total de Autores: 7
Afiliação do(s) autor(es):
[1] Univ Sao Paulo, Inst Geociencias, BR-05508900 Sao Paulo - Brazil
Número total de Afiliações: 1
Tipo de documento: Artigo Científico
Fonte: GONDWANA RESEARCH; v. 19, n. 1, SI, p. 260-274, JAN 2011.
Citações Web of Science: 15
Resumo

The results of geological mapping, chemical analysis and radiometric dating of metabasic rocks of Betara Formation, and mapping and dating of those present in the Betara basement nucleus together with mylonitic granodiorite and syenogranite are reported here. U-Pb analysis of bulk zircon fractions from the metabasic rocks of the basement nucleus yielded a Statherian age of 1790 +/- 22 Ma, while the metabasic rocks from the upper part of the Betara Formation yielded a Calymmian age between 1500 and 1450 Ma. This age is a minimum for the deposition of the Betara Formation. The older metabasic rocks are associated with post-tectonic, possibly anorogenic syenogranite, while the younger ones are gabbro or very porphyritic ankaramite whose REE patterns are consistent with crystallization from an N-MORB parent magma. The observations and data point to the probable events associated with extensional processes of the end of Paleoproterozoic and early Mesoproterozoic. Similar registers of Statherian (1.80-1.75 Ga) and Calymmian (1.50-1.45 Ga) extensional events are recorded in other parts of the South American and African continents. The Neoproterozoic witnessed the formation and junction of the tectonic slices which formed the Apiai domain during the assemblage of western Gondwana. (C) 2010 International Association for Gondwana Research. Published by Elsevier B.V. All rights reserved. (AU)

Processo FAPESP: 05/58688-1 - A América do Sul no contexto dos supercontinentes: fusão e fissão
Beneficiário:Miguel Angelo Stipp Basei
Linha de fomento: Auxílio à Pesquisa - Temático
Processo FAPESP: 06/03608-6 - Estudo geocronológico e litogeoquimico do domínio Paranaguá (Iguape/ SP - São Francisco do Sul/ SC): implicações tectônicas
Beneficiário:Oswaldo Siga Junior
Linha de fomento: Auxílio à Pesquisa - Regular