U-Pb detrital zircon ages of upper jurassic continental successions: Implications for the provenance and absolute age of the jurassic-cretaceous boundary in the Neuquén Basin
Registro en:
Naipauer, Maximiliano., Tunik, Maisa A., Marques, Juliana C., Rojas Vera, Emilio A., Vujovich, Graciela I., y et al. (2015) U-Pb detrital zircon ages of upper jurassic continental successions: Implications for the provenance and absolute age of the jurassic-cretaceous boundary in the Neuquén Basin. Geological Soc Publ House; Geological Society of London Special Publication; 399; 131-154
0305-8719
Autor
Naipauer, Maximiliano
Tunik, Maisa A.
Marques, Juliana C.
Rojas Vera, Emilio A.
Vujovich, Graciela I.
Pimentel, Marcio P.
Ramos, Victor A.
Institución
Resumen
Fil: Naipauer, Maximiliano. Consejo Nacional de Investigaciones Científicas y Técnicas. Buenos Aires, Argentina. Fil: Tunik, Maisa A. Universidad Nacional de Río Negro. Instituto de Investigaciones en Paleobiología y Geología. Río Negro, Argentina. Fil: Marques, Juliana C. Universidade Federal do Rio Grande do Sul. Laboratorio de Geología Isotópica; Brasil. Fil: Rojas Vera, Emilio A. Consejo Nacional de Investigaciones Científicas y Técnicas. Buenos Aires, Argentina. Fil: Vujovich, Graciela I. Consejo Nacional de Investigaciones Científicas y Técnicas. Buenos Aires, Argentina. Fil: Pimentel, Marcio. Universidade Federal do Rio Grande do Sul. Laboratorio de Geología Isotópica; Brasil. Fil: Ramos, Victor A. Consejo Nacional de Investigaciones Científicas y Técnicas. Buenos Aires, Argentina. Fil: Naipauer, Maximiliano. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber". Buenos Aires, Argentina. Fil: Tunik, Maisa A. Consejo Nacional de Investigaciones Científicas y Técnicas. Buenos Aires, Argentina. Fil: Rojas Vera, Emilio A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber". Buenos Aires, Argentina. Fil: Vujovich, Graciela I. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber". Buenos Aires, Argentina. Fil: Ramos, Victor A. Universidad de Buenos Aires. Facultad de Ciencias Exactas y Naturales. Instituto de Estudios Andinos "Don Pablo Groeber". Buenos Aires, Argentina. true New U-Pb detrital zircon ages are presented for the Tordillo Formation. The ages indicate that the most important source region of sediment supply was the Jurassic Andean arc (peaks at c. 144, 153 and 178 Ma), although two secondary sources were defined at c. 218 and 275 Ma. Temporal variation in the provenance indicates that at the beginning of the sedimentation, Carboniferous to Lower Jurassic magmatic rocks and Lower Palaeozoic metamorphic rocks were the most important sources. Towards the top, the data suggest that the Andean arc becomes the main source region. The comparison between provenance patterns of the Tordillo Formation and of the Avilé Member (Agrio Formation) showed some differences. In the former, the arc region played a considerable role as a source region, but this is not identified in the latter. The results permit a statistically robust estimation of the maximum deposition age for the Tordillo Formation at c. 144 Ma. This younger age represents a discrepancy of at least 7 Ma from the absolute age of the Kimmeridgian and Tithonian boundary (from the chronostratigraphic timescale accepted by the International Commission of Stratigraphy, IUGS), and has strong implications for the absolute age of the Jurassic-Cretaceous boundary.