High-precision U-Pb zircon age from the Anfiteatro de Ticó Formation: Implications for the timing of the early angiospermdiversification in Patagonia

The Baqueró Group is one of the most relevant units regarding the study of the early diversification of angiosperms in South America. Whereas the age of the upper part of the Group, namely the Punta del Barco Formation, has been recently dated at 114.67 ± 0.18 Ma, the rest of the unit still lacks pr...

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Detalhes bibliográficos
Autores: Perez Loinaze, Valeria Susana, Vera, Ezequiel Ignacio, Passalia, Mauro Gabriel, Llorens, Magdalena, Friedman, Richard, Limarino, Carlos Oscar, Cesari, Silvia Nelida
Tipo de documento: artigo
Estado:Versão publicada
Data de publicação:2013
País:Argentina
Recursos:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositório:CONICET Digital (CONICET)
Idioma:inglês
OAI Identifier:oai:ri.conicet.gov.ar:11336/5366
Acesso em linha:http://hdl.handle.net/11336/5366
Access Level:Acceso aberto
Palavra-chave:Cretaceous
Aptian
Palynology
Paleobotany
https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
Descrição
Resumo:The Baqueró Group is one of the most relevant units regarding the study of the early diversification of angiosperms in South America. Whereas the age of the upper part of the Group, namely the Punta del Barco Formation, has been recently dated at 114.67 ± 0.18 Ma, the rest of the unit still lacks precise dating. In this contribution a CA-TIMS U–Pb zircon age of 118.23 ± 0.09 Ma for a tuff interlayered with fossiliferous rocks of the Anfiteatro de Ticó Formation (lower part of the Baqueró Group) is reported. This age constrains the duration of deposition of the Baqueró Group to approximately 4 Ma and provides new evidence for the age interpretation of the previously described angiosperm flora and associated pollen assemblages from this unit, until now interpreted as early Aptian or possibly Barremian in age. The Aptian age of the Baqueró Group allows a better comparison between the paleofloras from this southernmost region.