Transient global cooling at the onset of early Aptian oceanic anoxic event (OAE) 1a

Research Article| April 01, 2011 Transient global cooling at the onset of early Aptian oceanic anoxic event (OAE) 1a Wolfgang Kuhnt; Wolfgang Kuhnt 1Institut für Geowissenschaften, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, 24118 Kiel, Germany Search for other works by this author on: GSW Google Scholar Ann Holbourn; Ann Holbourn 1Institut für Geowissenschaften, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, 24118 Kiel, Germany Search for other works by this author on: GSW Google Scholar Michel Moullade Michel Moullade 2Centre de Recherches Micropaléontologiques, Muséum d'Histoire Naturelle, 60 Bd Risso, 06300 Nice, and Centre de Sédimentologie-Paléontologie, EA 4234, Université de Provence (Aix-Marseille I), Campus St. Charles, 3 Pl. Victor Hugo, 13331 Marseille Cedex 03, France Search for other works by this author on: GSW Google Scholar Author and Article Information Wolfgang Kuhnt 1Institut für Geowissenschaften, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, 24118 Kiel, Germany Ann Holbourn 1Institut für Geowissenschaften, Christian-Albrechts-Universität zu Kiel, Olshausenstrasse 40, 24118 Kiel, Germany Michel Moullade 2Centre de Recherches Micropaléontologiques, Muséum d'Histoire Naturelle, 60 Bd Risso, 06300 Nice, and Centre de Sédimentologie-Paléontologie, EA 4234, Université de Provence (Aix-Marseille I), Campus St. Charles, 3 Pl. Victor Hugo, 13331 Marseille Cedex 03, France Publisher: Geological Society of America Received: 12 Jul 2010 Revision Received: 19 Oct 2010 Accepted: 08 Nov 2010 First Online: 09 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2011 Geological Society of America Geology (2011) 39 (4): 323–326. https://doi.org/10.1130/G31554.1 Article history Received: 12 Jul 2010 Revision Received: 19 Oct 2010 Accepted: 08 Nov 2010 First Online: 09 Mar 2017 Cite View This Citation Add to Citation Manager Share Icon Share Facebook Twitter LinkedIn MailTo Tools Icon Tools Get Permissions Search Site Citation Wolfgang Kuhnt, Ann Holbourn, Michel Moullade; Transient global cooling at the onset of early Aptian oceanic anoxic event (OAE) 1a. Geology 2011;; 39 (4): 323–326. doi: https://doi.org/10.1130/G31554.1 Download citation file: Ris (Zotero) Refmanager EasyBib Bookends Mendeley Papers EndNote RefWorks BibTex toolbar search Search Dropdown Menu toolbar search search input Search input auto suggest filter your search All ContentBy SocietyGeology Search Advanced Search Abstract The onset of the early Aptian oceanic anoxic event (OAE) 1a (ca. 120 Ma) coincided with a major perturbation of the carbon cycle, which is reflected in the sedimentary carbon isotope record. Triggering mechanisms, duration, and climatic repercussions of this episode of accelerated organic matter burial remain poorly constrained. Here, we present millennial-scale bulk rock carbon and oxygen isotope data from a marly subtropical intrashelf basin (La Bédoule, southeast France) with unusually high sedimentation rates, which track the onset of OAE1a in unprecedented resolution. Our record reveals that the negative, low-amplitude δ13C excursion preceding OAE1a lasted >100 k.y., implying that enhanced volcanic CO2 emission and/or pulsed methane dissociation over a prolonged time span were instrumental in triggering OAE1a. The main positive carbon isotope shift at the onset of OAE1a, previously regarded as continuous, occurred stepwise over an extended period of >300 k.y. Transient climate cooling during the initial δ13C increase probably reflects ephemeral high-latitude glaciation, triggered by changes in radiative forcing and drawdown of atmospheric CO2. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.