HR: 14:40h
AN: PP43D-04 INVITED    [Abstracts]
TI: Fresh and Warm Arctic Ocean Surface Waters During Eocene Thermal Maximum 2
AU: * Sluijs, A
EM: A.Sluijs@uu.nl
AF: Palaeoecology, Institute of Environmental Biology, Utrecht University, Laboratory of Palaeobotany and Palynology, Budapestlaan 4, Utrecht, 3584CD, Netherlands
AU: Schouten, S
EM: schouten@nioz.nl
AF: Royal Netherlands Institute for Sea Research (NIOZ), Department of Marine Biogeochemistry and Toxicology, PO Box 59, Den Burgh, Texel, 1790 AB, Netherlands
AU: Röhl, U
EM: uroehl@marum.de
AF: Center for Marine Environmental Sciences (MARUM), Bremen University, Leobener Strasse, Bremen, 28359, Germany
AU: Reichart, G
EM: reichart@geo.uu.nl
AF: Department of Earth Sciences, Utrecht University, Budapestlaan 4, Utrecht, 3584CD, Netherlands
AU: Sinninghe Damsté, J S
EM: damste@nioz.nl
AF: Royal Netherlands Institute for Sea Research (NIOZ), Department of Marine Biogeochemistry and Toxicology, PO Box 59, Den Burgh, Texel, 1790 AB, Netherlands
AU: Sinninghe Damsté, J S
EM: damste@nioz.nl
AF: Department of Earth Sciences, Utrecht University, Budapestlaan 4, Utrecht, 3584CD, Netherlands
AU: Sangiorgi, F
EM: f.sangiorgi@uu.nl
AF: Palaeoecology, Institute of Environmental Biology, Utrecht University, Laboratory of Palaeobotany and Palynology, Budapestlaan 4, Utrecht, 3584CD, Netherlands
AU: Sangiorgi, F
EM: f.sangiorgi@uu.nl
AF: Royal Netherlands Institute for Sea Research (NIOZ), Department of Marine Biogeochemistry and Toxicology, PO Box 59, Den Burgh, Texel, 1790 AB, Netherlands
AU: Krishnan, S
EM: srinath.krishnan@yale.edu
AF: Department of Geology and Geophysics, Yale University, P.O. Box 208109, New Haven, CT 06520,
AU: Pagani, M
EM: mark.pagani@yale.edu
AF: Department of Geology and Geophysics, Yale University, P.O. Box 208109, New Haven, CT 06520,
AU: Brinkhuis, H
EM: h.brinkhuis@uu.nl
AF: Palaeoecology, Institute of Environmental Biology, Utrecht University, Laboratory of Palaeobotany and Palynology, Budapestlaan 4, Utrecht, 3584CD, Netherlands
AB: Eocene Thermal Maximum 2 , at about 53.5 Ma (further referred to as the Elmo phase), was a short-lived (approximately 50 kyr) episode of widespread deep sea carbonate dissolution and warming. The few published records suggest that climate change during the Elmo phase was similar to the well known Paleocene-Eocene thermal maximum (PETM) at 55.5 Ma, but of a smaller magnitude. The Elmo phase was only recently discovered and the lack of climate records inhibits detailed description of the global change, as well as comparison to the PETM. We present micropaleontological (dinoflagellate cyst), organic geochemical (TEX₈₆, BIT, stable carbon isotopes of bulk organics and n-alkanes) and inorganic geochemical (XRF) data from the Elmo section recovered from the Lomonosov Ridge, Arctic Ocean, during IODP Expedition 302 (ACEX). The stable carbon isotope record on total organic carbon (TOC) shows a 3.5 ‰ negative carbon isotope excursion at the onset of the Elmo, 1 to 1.5 ‰ smaller than that usually recorded in TOC for the PETM. Dinocyst assemblages show a freshening of Arctic Ocean surface waters, while TEX₈₆-derived paleotemperatures show a rise from about 18 to 22 ° C. Moreover, laminated sediments and the absence of organic foraminiferal linings suggest that anoxia developed at the sediment-water interface. Biomarker analyses also indicate euxinic conditions in the photic zone. All trends, including those recorded using XRF core scanning techniques, mimic those observed during the PETM but exhibit a slightly smaller magnitude. Our findings, together with the scant published data, corroborate the notion that the Elmo was indeed a true global warming phase, associated with the rapid injection of light carbon.
DE: 4855 Phytoplankton
DE: 4930 Greenhouse gases
DE: 4952 Palynology
DE: 4954 Sea surface temperature
DE: 4958 Speleothems
SC: Paleoceanography and Paleoclimatology [PP]
MN: 2007 Fall Meeting