The Lower Cretaceous Chanarcillo and Neuquen Andean basins: ammonoid biostratigraphy and correlations

• Published in: Geological Journal
• Main Authors: Aguirre-Urreta, M.Beatriz, Mourgues, F.Amaro, Rawson, Peter.F., Bulot, Luc Georges, Jaillard, Etienne
• Other Authors: Laboratorio de Bioestratigrafıa de Alta Resolucion Buenos Aires, Instituto de Estudios Andinos “Don Pablo Groeber” (INDEAN), Consejo Nacional de Investigaciones Científicas y Técnicas Buenos Aires (CONICET)-Facultad de Ciencias Exactas y Naturales Buenos Aires (FCEyN), Universidad de Buenos Aires Buenos Aires (UBA)-Universidad de Buenos Aires Buenos Aires (UBA)-Consejo Nacional de Investigaciones Científicas y Técnicas Buenos Aires (CONICET)-Facultad de Ciencias Exactas y Naturales Buenos Aires (FCEyN), Universidad de Buenos Aires Buenos Aires (UBA)-Universidad de Buenos Aires Buenos Aires (UBA), Servicio Nacional de Geologia y Mineria (SERNAGEOMIN), Laboratoire des Mécanismes et Transfert en Géologie (LMTG), Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Observatoire Midi-Pyrénées (OMP), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université de Toulouse (UT)-Université de Toulouse (UT)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France-Centre National de la Recherche Scientifique (CNRS), Department of Earth Sciences UCL London, University College of London London (UCL), Centre de sédimentologie-paléontologie, Université de Provence - Aix-Marseille 1-Centre National de la Recherche Scientifique (CNRS), Laboratoire de Géodynamique des Chaines Alpines (LGCA), Observatoire des Sciences de l'Univers de Grenoble (OSUG), Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Université Joseph Fourier - Grenoble 1 (UJF)-Institut polytechnique de Grenoble - Grenoble Institute of Technology (Grenoble INP)-Institut national des sciences de l'Univers (INSU - CNRS)-Institut national de recherche en sciences et technologies pour l'environnement et l'agriculture (IRSTEA)-Université Savoie Mont Blanc (USMB Université de Savoie Université de Chambéry )-Centre National de la Recherche Scientifique (CNRS)-Centre National de la Recherche Scientifique (CNRS)
• Format: Article in Journal/Newspaper
• Language: English
• Published: CCSD 2007
• Subjects: ammonites; biostratigraphy; correlations; Chanarcillo Basin; Neuquen Basin; South America; Lower Cretaceous; Antarctic; Pacific; Antarc*
• Online Access: https://insu.hal.science/insu-00253893; https://doi.org/10.1002/gj.1068

International audience The Chan˜arcillo and Neuque´n basins of the Central Andes shared a common geological history in the earlier part of the Early Cretaceous but from Barremian times onward their evolution began to diverge, probably due to an increasing activity of an intervening volcanic arc. The Berriasian to Lower Barremian sequences were mainly marine and include rich ammonoid faunas, with many taxa in common to both the basins. They include both Andean and near-pandemic forms, the latter providing some good correlation levels with the ‘standard' Mediterranean sequence. Marine conditions persisted in the Chan˜arcillo Basin till Early Albian times; the associated ammonoid faunas include pandemic, Pacific and Antarctic genera. In contrast, in the Neuquen Basin evaporites and continental clastics of the Huitrı´n Formation mark the beginning of a long disconnection with the Pacific Ocean, though a short-lived marine incursion is represented by the carbonates of La Tosca Member of the Huitrı´n Formation. The ammonoid faunas of the two basins are compared here, and a detailed biostratigraphic division of the sequences is discussed and compared with the Mediterranean succession.