georefid:2011-047941SEDIS Publication Catalogue

ana.macario@awi.de

http://sedis.iodp.org/pub-catalogue/informationpointOfContact2011-07-06T00:00:00Zhttp://sedis.iodp.org/pub-catalogue/index.php?id=2011-0479412010-01-01publicationgeorefid:2011-047941Ando, AtsushiResearch Institute for Humanity and Nature, Kyoto, JapanauthorNakano, TakanoriPusan National University, South KoreaauthorKawahata, HodakaUniversity of Tokyo, JapanauthorYokoyama, YusukeJapan Agency for Marine-Earth Science and Technology, JapanauthorKhim, Boo-KeunauthorGeochemical Society of Japan, Nagoya, JapanpublisherdocumentHardcopyGeochemical Journal44 (5)347-357Stability in seawater (super 87) Sr/ (super 86) Sr ratios over a glacial-interglacial timescale has gained the consensus, yet inter-site inconsistency exists in the previous data employed for validation of this issue. This study tests if the use of state-of-the-art Thermo Finnigan (super TM) TRITON multi-collector thermal ionization mass spectrometer (TIMS) can place more rigorous constraints on the seawater (super 87) Sr/ (super 86) Sr evolution at such a narrow timescale, by utilizing modern seawater, benthic foraminifera (150 ka-present) and corals (30 ka-present) (all sampled from the western Pacific realm). Application of a high-intensity setting (mass (super 88) Sr beam at 20 V) with internal and external precisions of + or -0.000005 (2 SE) and + or -0.000006 (2 SD), respectively, generates remarkably consistent 150 ka record of seawater Sr isotopes, such that 94.4% of foraminiferal (super 87) Sr/ (super 86) Sr data fall within a + or -0.000006 envelope relative to a regression function. Undoubtedly the 150 ka (super 87) Sr/ (super 86) Sr trend exhibits no short-term, orbitally-paced variation. Meanwhile, unlike previous inference, our (super 87) Sr/ (super 86) Sr record cannot be attributed to a simple linear function, implying that higher-order, minor (amplitude < or =0.000010) (super 87) Sr/ (super 86) Sr oscillation might have been present on the timescale greater than glacial-interglacial cycle. Our observations are demonstrative data-based verification and improvement upon previous knowledge of the glacial-interglacial seawater (super 87) Sr/ (super 86) Sr ratios. We emphasize that high-precision (super 87) Sr/ (super 86) Sr analysis with the TRITON TIMS certainly enables us to discriminate minute Sr isotopic details of (paleo-)oceanographic significance.completedIsotope geochemistryalkaline earth metalsAnthozoabenthic taxaCenozoicCnidariaDeep Sea Drilling ProjectDSDP Site 463Foraminiferaglacial-interglacial cyclesInvertebrataIPODisotope ratiosisotopesLeg 62marine sedimentsmass spectrametalsmicrofossilsMid-Pacific MountainsNorth PacificNorthwest PacificoscillationsPacific Oceanpaleo-oceanographyPleistoceneprecisionProtistaQuaternarysea watersedimentsShatsky RisespectraSr-87/Sr-86stable isotopesstrontiumthermal ionization mass spectraWest Pacificurn:org.iodp:exp:62urnlargerWorkCitationcampaignurn:org.iodp:exp:62:site:463urnlargerWorkCitationstudyurn:org.iodp:exp:62urnlargerWorkCitationcampaignEnglishgeoscientificInformation157.5100174.400421.210132.1950