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Astronomical tuning of the Aptian stage and its implications for age recalibrations and paleoclimatic events.

ABSTRACT: The Aptian was characterized by dramatic tectonic, oceanographic, climatic and biotic changes and its record is punctuated by Oceanic Anoxic Events (OAEs). The timing and duration of these events are still contentious, particularly the age of the Barremian-Aptian boundary. This study presents a cyclostratigraphic evaluation of a high-resolution multiproxy dataset (δ¹³C, δ¹⁸O, MS and ARM) from the Poggio le Guaine core. The identification of Milankovitch-band imprints allowed us to construct a 405-kyr astronomically-tuned age model that provides new constraints for the Aptian climato-chronostratigraphic framework. Based on the astronomical tuning, we propose: (i) a timespan of ~7.2 Myr for the Aptian; (ii) a timespan of ~420 kyr for the magnetic polarity Chron M0r and an age of ~120.2 Ma for the Barremian-Aptian boundary; and (iii) new age constraints on the onset and duration of Aptian OAEs and the 'cold snap'. The new framework significantly impacts the Early Cretaceous geological timescale.

SUBMITTER: Leandro CG

PROVIDER: S-EPMC9135687 | biostudies-literature | 2022 May

REPOSITORIES: biostudies-literature

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Astronomical tuning of the Aptian stage and its implications for age recalibrations and paleoclimatic events.

Leandro C G CG Savian J F JF Kochhann M V L MVL Franco D R DR Coccioni R R Frontalini F F Gardin S S Jovane L L Figueiredo M M Tedeschi L R LR Janikian L L Almeida R P RP Trindade R I F RIF

Nature communications 20220526 1

The Aptian was characterized by dramatic tectonic, oceanographic, climatic and biotic changes and its record is punctuated by Oceanic Anoxic Events (OAEs). The timing and duration of these events are still contentious, particularly the age of the Barremian-Aptian boundary. This study presents a cyclostratigraphic evaluation of a high-resolution multiproxy dataset (δ<sup>13</sup>C, δ<sup>18</sup>O, MS and ARM) from the Poggio le Guaine core. The identification of Milankovitch-band imprints allowe ...[more]

PMID: 35618707

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Dataset Information

Astronomical tuning of the Aptian stage and its implications for age recalibrations and paleoclimatic events.

Publications

Astronomical tuning of the Aptian stage and its implications for age recalibrations and paleoclimatic events.

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