000177113 001__ 177113
000177113 005__ 20181203022720.0
000177113 0247_ $$2doi$$a10.1029/2007GC001686
000177113 02470 $$2ISI$$a000251344700001
000177113 037__ $$aARTICLE
000177113 245__ $$aCorrelation of boron isotopic composition with ultrastructure in the deep- sea coral Lophelia pertusa: Implications for biomineralization and paleo-pH
000177113 269__ $$a2007
000177113 260__ $$c2007
000177113 336__ $$aJournal Articles
000177113 520__ $$aUsing the CRPG-CNRS Cameca 1270 ion microprobe facility, we have measured boron isotopic compositions (B-11/B-10) in different ultrastructural components of the deep-sea aragonitic scleractinian coral Lophelia pertusa. We observe a systematic difference in B isotopic composition between the Early Mineralization Zone ( EMZ) and adjacent fibrous skeleton. In EMZ the measured delta(11) B values are consistently low. Fibrous aragonite is characterized by systematically higher delta(11) B values but also displays B isotopic heterogeneity associated with specific growth bands in the calyx wall. The magnitude of the observed B isotopic variations cannot be explained by changes in environmental conditions and is likely caused by biological processes involved in the biomineralization of new skeleton, i. e., " vital'' effects. The observed B isotopic variations are opposite to the predictions of geochemical models for vital effects. These models are based on the idea that stable isotopic fractionations ( including C and O) in coral skeleton are driven by changes in pH of the fluid from which the skeleton is presumed to precipitate. Our data indicate that pH variations are not responsible for the observed stable isotopic fractionations. Geochemical models therefore do not provide an adequate framework within which to understand coral skeletal formation. Without a better understanding of these processes the use of B isotopic composition to reconstruct paleo- pH variations in the oceans must be considered problematic, at least as far as Lophelia pertusa is concerned.
000177113 6531_ $$aboron isotopes
000177113 6531_ $$adeep-sea coral
000177113 6531_ $$abiomineralization
000177113 6531_ $$aaragonite
000177113 6531_ $$amicrostructure
000177113 6531_ $$apH
000177113 6531_ $$aCarbon-Dioxide Concentrations
000177113 6531_ $$aNorth-Atlantic
000177113 6531_ $$aOcean Ph
000177113 6531_ $$aBiological Carbonates
000177113 6531_ $$aCalcium-Carbonate
000177113 6531_ $$aSeawater
000177113 6531_ $$aForaminifera
000177113 6531_ $$aVentilation
000177113 6531_ $$aSkeletons
000177113 6531_ $$aAcropora
000177113 700__ $$aBlamart, D.
000177113 700__ $$aRollion-Bard, C.
000177113 700__ $$0246343$$aMeibom, A.$$g220185
000177113 700__ $$aCuif, J. -P.
000177113 700__ $$aJuillet-Leclerc, A.
000177113 700__ $$aDauphin, Y.
000177113 773__ $$j8$$q-$$tGeochemistry Geophysics Geosystems
000177113 909C0 $$0252426$$pLGB$$xU12552
000177113 909CO $$ooai:infoscience.tind.io:177113$$particle$$pENAC
000177113 937__ $$aEPFL-ARTICLE-177113
000177113 973__ $$aOTHER$$rREVIEWED$$sPUBLISHED
000177113 980__ $$aARTICLE