Rapid warming and salinity changes of Cretaceous surface waters in the subtropical North Atlantic

Research Article| March 01, 2008 Rapid warming and salinity changes of Cretaceous surface waters in the subtropical North Atlantic Thomas Wagner; Thomas Wagner 1School of Civil Engineering and Geosciences, Newcastle University, Devonshire Building, Newcastle upon Tyne NE1 7RU, UK Search for other works by this author on: GSW Google Scholar Jens O. Herrle; Jens O. Herrle 2Department of Earth and Atmospheric Sciences, 1-26 Earth Sciences Building, University of Alberta, Edmonton, Alberta T6G 2E3, Canada Search for other works by this author on: GSW Google Scholar Jaap S. Sinninghe Damsté; Jaap S. Sinninghe Damsté 3Department of Marine Biogeochemistry and Toxicology, Royal Netherlands Institute for Sea Research, P.O. Box 59, 1790 AB Den Burg, Texel, Netherlands Search for other works by this author on: GSW Google Scholar Stefan Schouten; Stefan Schouten 3Department of Marine Biogeochemistry and Toxicology, Royal Netherlands Institute for Sea Research, P.O. Box 59, 1790 AB Den Burg, Texel, Netherlands Search for other works by this author on: GSW Google Scholar Isabel Stüsser; Isabel Stüsser 4Institute for Geology and Mineralogy, University of Cologne, Zülpicher Strasse 49a, 50674 Köln, Germany Search for other works by this author on: GSW Google Scholar Peter Hofmann Peter Hofmann 4Institute for Geology and Mineralogy, University of Cologne, Zülpicher Strasse 49a, 50674 Köln, Germany Search for other works by this author on: GSW Google Scholar Geology (2008) 36 (3): 203–206. https://doi.org/10.1130/G24523A.1 Article history received: 19 Feb 2007 rev-recd: 30 Oct 2007 accepted: 30 Oct 2007 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 Thomas Wagner, Jens O. Herrle, Jaap S. Sinninghe Damsté, Stefan Schouten, Isabel Stüsser, Peter Hofmann; Rapid warming and salinity changes of Cretaceous surface waters in the subtropical North Atlantic. Geology 2008;; 36 (3): 203–206. doi: https://doi.org/10.1130/G24523A.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 Paleomarine carbon isotopic records reveal occasional and rapid release of greenhouse gases into the atmosphere. The regional consequences on surface ocean properties and time relationships between the atmosphere and the ocean, however, are still far from understood. We observe a sudden -1.5‰ shift in leaf wax n-alkane 13C values at the onset of oceanic anoxic event (OAE) 1b from early Albian sediments off northwest Africa (Deep Sea Drilling Project Site 545) that is best explained by the rapid release of isotopically light carbon into the Cretaceous atmosphere. This -1.5‰ shift in the n-alkanes precedes a negative isotope excursion of similar magnitude observed in marine carbonate, organic matter, and algal steranes. A TEX86-based record of sea surface temperature (SST) confirms almost instantaneous warming by ∼3.5 °C along with the marine isotope shifts at Site 545, paralleled by an ∼2 °C TEX86-SST increase and a freshening of surface water salinity from 43 to 41 at Blake Nose, Ocean Drilling Program Site 1049. Multiproxy evidence indicates that, once established, these warm SSTs prevailed and were stable during OAE 1b, suggesting that the emission of 13C-depleted carbon started abruptly but then continued over tens of thousands of years. The SST cooled by ∼1–2 °C at the end of the event, not reaching pre-excursion levels. The new records provide evidence for a time lag (best estimate ∼1–3 k.y.) between atmospheric and oceanic processes that we interpret as a direct response to changes in the atmospheric greenhouse gas concentrations followed by propagation into the ocean and subsequent heating of surface waters. You do not have access to this content, please speak to your institutional administrator if you feel you should have access.