IGEBA   23946
INSTITUTO DE GEOCIENCIAS BASICAS, APLICADAS Y AMBIENTALES DE BUENOS AIRES
Unidad Ejecutora - UE
artículos
Título:
High-precision UePb zircon age from the Anfiteatro de Ticó Formation: Implications for the timing of the early angiosperm diversification in Patagonia
Autor/es:
V.S. PEREZ LOINAZE; EZEQUIEL IGNACIO VERA; MAURO PASSALIA; FRIEDMAN RICHARD; C.O. LIMARINO; MAGDALENA LLORENS; CESARI, S.N.
Revista:
JOURNAL OF SOUTH AMERICAN EARTH SCIENCES
Editorial:
PERGAMON-ELSEVIER SCIENCE LTD
Referencias:
Lugar: Amsterdam; Año: 2013 vol. 48 p. 97 - 105
ISSN:
0895-9811
Resumen:
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 UePb 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.