First U-Pb SHRIMP age of the Hauterivian stage, Neuquén Basin, Argentina

A high-resolution ion-microprobe (SHRIMP) U-Pb zircon age from a tuff layer intercalated in the ammonoid bearing sedimentary succession of the Neuquén Basin in Argentina provides a robust geochronologic date to add to the absolute ages and to improve the relative chronology of the Early Cretaceous H...

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Bibliographic Details
Authors: Aguirre Urreta, Maria Beatriz, Pazos, Pablo Jose, Lazo, Dario Gustavo, Fanning, Christopher Mark, Litvak, Vanesa Dafne
Format: article
Status:Published version
Publication Date:2008
Country:Argentina
Institution:Consejo Nacional de Investigaciones Científicas y Técnicas
Repository:CONICET Digital (CONICET)
Language:English
OAI Identifier:oai:ri.conicet.gov.ar:11336/92715
Online Access:http://hdl.handle.net/11336/92715
Access Level:Open access
Keyword:BIOSTRATIGRAPHY
HAUTERIVIAN
LOWER CRETACEOUS
NEUQUÉN BASIN
TETHYS
U-PB SHRIMP GEOCHRONOLOGY
https://purl.org/becyt/ford/1.5
https://purl.org/becyt/ford/1
Description
Summary:A high-resolution ion-microprobe (SHRIMP) U-Pb zircon age from a tuff layer intercalated in the ammonoid bearing sedimentary succession of the Neuquén Basin in Argentina provides a robust geochronologic date to add to the absolute ages and to improve the relative chronology of the Early Cretaceous Hauterivian stage. The tuff layer appears interbedded between shales of the upper member (Agua de la Mula) of the Agrio Formation within the Spitidiscus riccardii ammonoid zone (base of the Late Hauterivian) yielding a date of 132.5 ± 1.3 Ma. This date confirms and supports an accurate correlation between the ammonoid biostratigraphy of the Neuquén Basin with the Western Mediterranean Province of the Tethys during the Early Cretaceous and matches with the most recently published time scale. It also casts doubts on the validity of K-Ar ages on glauconite-grains recently reported from the Lower Cretaceous of the Vocontian Basin of France.