untitled
<OAI-PMH schemaLocation=http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd>
<responseDate>2018-01-15T15:42:59Z</responseDate>
<request identifier=oai:HAL:hal-00320075v1 verb=GetRecord metadataPrefix=oai_dc>http://api.archives-ouvertes.fr/oai/hal/</request>
<GetRecord>
<record>
<header>
<identifier>oai:HAL:hal-00320075v1</identifier>
<datestamp>2018-01-11</datestamp>
<setSpec>type:ART</setSpec>
<setSpec>subject:sdu</setSpec>
<setSpec>collection:CNRS</setSpec>
<setSpec>collection:UNIV-PARIS7</setSpec>
<setSpec>collection:UNIV-TLSE3</setSpec>
<setSpec>collection:UNIV-BPCLERMONT</setSpec>
<setSpec>collection:UNIV-ST-ETIENNE</setSpec>
<setSpec>collection:INSU</setSpec>
<setSpec>collection:IPGP</setSpec>
<setSpec>collection:OMP-LMTG</setSpec>
<setSpec>collection:GM</setSpec>
<setSpec>collection:LMV</setSpec>
<setSpec>collection:UPMC</setSpec>
<setSpec>collection:OMP</setSpec>
<setSpec>collection:PRES_CLERMONT</setSpec>
<setSpec>collection:OMP-GET</setSpec>
<setSpec>collection:AGROPOLIS</setSpec>
<setSpec>collection:USPC</setSpec>
<setSpec>collection:UNIV-AG</setSpec>
<setSpec>collection:B3ESTE</setSpec>
<setSpec>collection:UNIV-MONTPELLIER</setSpec>
<setSpec>collection:OPGC</setSpec>
</header>
<metadata><dc>
<publisher>HAL CCSD</publisher>
<title lang=en>The scale and origin of the osmium isotope variations in mid-ocean ridge basalts</title>
<creator>Gannoun, A.</creator>
<creator>Burton, K. W.</creator>
<creator>Parkinson, I. J.</creator>
<creator>Alard, O.</creator>
<creator>Schiano, P.</creator>
<creator>Thomas, L. E.</creator>
<contributor>Institut de Physique du Globe de Paris (IPGP) ; Université Pierre et Marie Curie - Paris 6 (UPMC) - Institut national des sciences de l'Univers (INSU - CNRS) - IPG PARIS - Université Paris Diderot - Paris 7 (UPD7) - Université de la Réunion (UR) - Centre National de la Recherche Scientifique (CNRS)</contributor>
<contributor>Laboratoire des Mécanismes et Transfert en Géologie (LMTG) ; Université Paul Sabatier - Toulouse 3 (UPS) - Observatoire Midi-Pyrénées (OMP) - Centre National de la Recherche Scientifique (CNRS)</contributor>
<contributor>Géosciences Montpellier ; Université des Antilles et de la Guyane (UAG) - Institut national des sciences de l'Univers (INSU - CNRS) - Université de Montpellier (UM) - Centre National de la Recherche Scientifique (CNRS)</contributor>
<contributor>Laboratoire Magmas et Volcans (LMV) ; Université Blaise Pascal - Clermont-Ferrand 2 (UBP) - Institut national des sciences de l'Univers (INSU - CNRS) - Université Jean Monnet [Saint-Étienne] (UJM) - Centre National de la Recherche Scientifique (CNRS)</contributor>
<description>International audience</description>
<source>ISSN: 0012-821X</source>
<source>Earth and Planetary Science Letters</source>
<publisher>Elsevier</publisher>
<identifier>hal-00320075</identifier>
<identifier>https://hal.archives-ouvertes.fr/hal-00320075</identifier>
<source>https://hal.archives-ouvertes.fr/hal-00320075</source>
<source>Earth and Planetary Science Letters, Elsevier, 2007, 259, pp.541-556. 〈10.1016/J.EPSL.2007.05.014〉</source>
<identifier>DOI : 10.1016/J.EPSL.2007.05.014</identifier>
<relation>info:eu-repo/semantics/altIdentifier/doi/10.1016/J.EPSL.2007.05.014</relation>
<language>en</language>
<subject>[SDU.STU] Sciences of the Universe [physics]/Earth Sciences</subject>
<type>info:eu-repo/semantics/article</type>
<type>Journal articles</type>
<description lang=en>The decay of 187Re to 187Os provides a unique tracer of recycled lithosphere in the Earth's upper mantle, and the radiogenic Os isotope compositions of many mid-ocean ridge basalts (MORB) have been taken to indicate the presence of recycled oceanic crust in the mantle source. However, others have attributed the data to contamination by seawater or an age effect (due to 187Re decay following igneous crystallisation). This study presents new Re Os, U Th Ra and B isotope data for normal-MORB (N-MORB) glass (including 18 samples analysed previously). The scale of the variation in 187Os/188Os observed here in N-MORB glass ranges from 0.126 to 0.148, with a mean value of 0.133 ± 0.009 (2?). Previously published Os isotope data for MORB is shown to have been affected by an analytical artefact, and in particular the very radiogenic Os isotope compositions reported earlier are now shown not to exist. Nevertheless, some radiogenic Os isotope compositions are still seen in the data obtained here. Coupled Th and Ra excesses appear to rule out an age effect, at least, for those samples studied, however, ?11B covariations with 187Os/188Os are consistent with the assimilation of older oceanic crust (affected by seawater contamination). Individual sulphides (less likely to be affected by such contamination) are always less radiogenic than their glass host, with 187Os/188Os values ranging from 0.123 to 0.131. This indicates that sulphide precipitation occurred prior to contamination of the surrounding melt, but the data also suggest that low-Os sulphides have been affected by contamination through partial equilibration with that melt. Taken together, these indicate that dominant process responsible for the radiogenic Os isotope compositions of N-MORB glass is contamination by older oceanic crust. Although the influence of age effects and the presence of recycled material cannot be completely ruled out, Os-rich sulphides yield sub-chondritic Os isotope compositions which point rather to a long-term depletion in Re in the MORB source likely to have resulted from formation of the continental crust over much of Earth's history.</description>
<date>2007-07</date>
</dc>
</metadata>
</record>
</GetRecord>
</OAI-PMH>
