A volcanic CO2 pulse triggered the Cretaceous Oceanic Anoxic Event 1a and a biocalcification crisis

Abstract

Research Article| September 01, 2009 A volcanic CO2 pulse triggered the Cretaceous Oceanic Anoxic Event 1a and a biocalcification crisis Sabine Méhay; Sabine Méhay 1Geological Institute, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Search for other works by this author on: GSW Google Scholar Christina E. Keller; Christina E. Keller 1Geological Institute, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Search for other works by this author on: GSW Google Scholar Stefano M. Bernasconi; Stefano M. Bernasconi 1Geological Institute, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Search for other works by this author on: GSW Google Scholar Helmut Weissert; Helmut Weissert 1Geological Institute, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Search for other works by this author on: GSW Google Scholar Elisabetta Erba; Elisabetta Erba 2Department of Earth Sciences, University of Milan, Via Mangiagalli 34, Milan I-20133, Italy Search for other works by this author on: GSW Google Scholar Cinzia Bottini; Cinzia Bottini 2Department of Earth Sciences, University of Milan, Via Mangiagalli 34, Milan I-20133, Italy Search for other works by this author on: GSW Google Scholar Peter A. Hochuli Peter A. Hochuli 3Paleontological Institute, University of Zürich, Karl Schmid-Strasse 4, CH-8006 Zürich, Switzerland Search for other works by this author on: GSW Google Scholar Author and Article Information Sabine Méhay 1Geological Institute, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Christina E. Keller 1Geological Institute, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Stefano M. Bernasconi 1Geological Institute, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Helmut Weissert 1Geological Institute, ETH Zürich, Sonneggstrasse 5, CH-8092 Zürich, Switzerland Elisabetta Erba 2Department of Earth Sciences, University of Milan, Via Mangiagalli 34, Milan I-20133, Italy Cinzia Bottini 2Department of Earth Sciences, University of Milan, Via Mangiagalli 34, Milan I-20133, Italy Peter A. Hochuli 3Paleontological Institute, University of Zürich, Karl Schmid-Strasse 4, CH-8006 Zürich, Switzerland Publisher: Geological Society of America Received: 03 Feb 2009 Revision Received: 21 Apr 2009 Accepted: 28 Apr 2009 First Online: 02 Mar 2017 Online ISSN: 1943-2682 Print ISSN: 0091-7613 © 2009 Geological Society of America Geology (2009) 37 (9): 819–822. https://doi.org/10.1130/G30100A.1 Article history Received: 03 Feb 2009 Revision Received: 21 Apr 2009 Accepted: 28 Apr 2009 First Online: 02 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 Sabine Méhay, Christina E. Keller, Stefano M. Bernasconi, Helmut Weissert, Elisabetta Erba, Cinzia Bottini, Peter A. Hochuli; A volcanic CO2 pulse triggered the Cretaceous Oceanic Anoxic Event 1a and a biocalcification crisis. Geology 2009;; 37 (9): 819–822. doi: https://doi.org/10.1130/G30100A.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 Aptian Oceanic Anoxic Event 1a (OAE1a, ca.120 Ma ago) is one of the most prominent of a series of geologically brief intervals in the Cretaceous characterized by the deposition of organic carbon–rich sediments. OAEs reflect major perturbations in the global carbon cycle evidenced by sedimentary carbon isotope records. However, the triggering mechanisms for OAEs remain controversial. Here we present a bulk-rock and molecular (marine and terrestrial bio-markers) C isotope record at unprecedented time resolution, from the Cismon section of northern Italy, that shows that OAE1a conditions were reached over a period of several thousands of years through a stepwise perturbation of the carbon cycle. The documented sequence of events is most compatible with a trigger associated with increased CO2 emissions, possibly leading to a doubling of pCO2, which in turn caused larger C isotope fractionation in marine and terrestrial organisms and a major biotic crisis in the calcareous nannoplankton. Our data also show that a release of isotopically light carbon from partial methane hydrate dissociation probably played a minor role in the OAE1a carbon cycle perturbation. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.