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<OAI-PMH schemaLocation=http://www.openarchives.org/OAI/2.0/ http://www.openarchives.org/OAI/2.0/OAI-PMH.xsd> <responseDate>2018-01-15T18:21:13Z</responseDate> <request identifier=oai:HAL:hal-00366222v1 verb=GetRecord metadataPrefix=oai_dc>http://api.archives-ouvertes.fr/oai/hal/</request> <GetRecord> <record> <header> <identifier>oai:HAL:hal-00366222v1</identifier> <datestamp>2018-01-11</datestamp> <setSpec>type:ART</setSpec> <setSpec>subject:sdu</setSpec> <setSpec>collection:LGSR</setSpec> <setSpec>collection:CNRS</setSpec> <setSpec>collection:UNIV-AG</setSpec> <setSpec>collection:GM</setSpec> <setSpec>collection:LMV</setSpec> <setSpec>collection:AGROPOLIS</setSpec> <setSpec>collection:UNIV-BPCLERMONT</setSpec> <setSpec>collection:ACL-SF</setSpec> <setSpec>collection:UNIV-ST-ETIENNE</setSpec> <setSpec>collection:INSU</setSpec> <setSpec>collection:PRES_CLERMONT</setSpec> <setSpec>collection:GEOPS</setSpec> <setSpec>collection:UNIV-PSUD</setSpec> <setSpec>collection:B3ESTE</setSpec> <setSpec>collection:UNIV-MONTPELLIER</setSpec> <setSpec>collection:OPGC</setSpec> </header> <metadata><dc> <publisher>HAL CCSD</publisher> <title lang=en>An integrated study of microstructural, geochemical, and seismic properties of the lithospheric mantle above the Kerguelen plume (Indian Ocean)</title> <creator>Bascou, Jerôme</creator> <creator>Delpech, G.</creator> <creator>Vauchez, A.</creator> <creator>Moine, B.N.</creator> <creator>Cottin, Jean-Yves</creator> <creator>Barruol, Guilhem</creator> <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> <contributor>Interactions et dynamique des environnements de surface (IDES) ; Université Paris-Sud - Paris 11 (UP11) - Institut national des sciences de l'Univers (INSU - CNRS) - 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> <description>International audience</description> <source>ISSN: 1525-2027</source> <source>EISSN: 1525-2027</source> <source>Geochemistry, Geophysics, Geosystems</source> <publisher>AGU and the Geochemical Society</publisher> <identifier>hal-00366222</identifier> <identifier>https://hal.archives-ouvertes.fr/hal-00366222</identifier> <identifier>https://hal.archives-ouvertes.fr/hal-00366222/document</identifier> <identifier>https://hal.archives-ouvertes.fr/hal-00366222/file/bascou_Kerguelen_2007GC001879_hal.pdf</identifier> <source>https://hal.archives-ouvertes.fr/hal-00366222</source> <source>Geochemistry, Geophysics, Geosystems, AGU and the Geochemical Society, 2008, 9 (Q04039), pp.1-26. 〈10.1029/2007GC001879〉</source> <identifier>DOI : 10.1029/2007GC001879</identifier> <relation>info:eu-repo/semantics/altIdentifier/doi/10.1029/2007GC001879</relation> <language>en</language> <subject lang=en>Kerguelen</subject> <subject lang=en>mantle plume</subject> <subject lang=en>seismic anisotropy</subject> <subject lang=en>metasomatism</subject> <subject lang=en>crystallographic fabric</subject> <subject lang=en>lithosphere</subject> <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>Peridotite xenoliths brought up to the surface by the volcanism of the Kerguelen Islands represent a mantle that has been affected by a high degree of partial melting followed by intense melt percolation above the Kerguelen plume. These xenoliths are therefore particularly suitable to investigate effects of melt-rock interaction on crystallographic fabrics (lattice-preferred orientation (LPO)) of peridotite minerals and on the LPO-induced seismic properties of peridotites above a mantle plume. We have studied a suite of 16 ultramafic samples representative of different degrees of partial melting and magma-rock interaction among which the protogranular harzburgites are the least metasomatised xenoliths and dunites are the ultimate stage of metasomatism. Olivine LPO is characterized by high concentration of [010] axes perpendicular to the foliation and [100] axes close to the lineation or distributed in the foliation plane in harzburgites, whereas the high concentration of [100] axes is parallel to the lineation and [010] axes is perpendicular to the assumed foliation in dunites. Olivine LPO in harzburgites is interpreted as being due to a deformation regime in axial compression or transpression. The fabric strength of olivine decreases progressively from protogranular to poikilitic harzburgites and finally to dunites, for which it remains nevertheless significant (J index 3.8). Seismic properties calculated from LPO of minerals indicate that metasomatism at higher melt/rock ratio lowers the P wave velocities. The most significant difference between harzburgites and dunites corresponds to the distribution of S wave anisotropy. Harzburgites display the maximum of anisotropy within the foliation plane and the minimum of anisotropy perpendicular to the foliation plane, whereas the lowest anisotropy is parallel to the lineation for dunites. These modifications of seismic properties as a result of metasomatic processes may induce seismic heterogeneities in the mantle above the Kerguelen plume. In addition, assuming a lithospheric mantle primarily harzburgitic and structured with a horizontal foliation, the seismic properties calculated for the Kerguelen xenoliths reconcile the rather high anisotropy evidenced by the horizontally propagating surface waves with the apparent isotropy revealed by the absence of splitting of vertically propagating teleseismic SKS waves recorded by the GEOSCOPE Kerguelen station.</description> <date>2008</date> </dc> </metadata> </record> </GetRecord> </OAI-PMH>