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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>2018-01-15T18:20:58Z</responseDate> <request identifier=oai:HAL:hal-01389712v1 verb=GetRecord metadataPrefix=oai_dc>http://api.archives-ouvertes.fr/oai/hal/</request> <GetRecord> <record> <header> <identifier>oai:HAL:hal-01389712v1</identifier> <datestamp>2018-01-11</datestamp> <setSpec>type:ART</setSpec> <setSpec>subject:sdu</setSpec> <setSpec>collection:UNIV-REUNION</setSpec> <setSpec>collection:CNRS</setSpec> <setSpec>collection:UNIV-AG</setSpec> <setSpec>collection:GM</setSpec> <setSpec>collection:AGROPOLIS</setSpec> <setSpec>collection:INSU</setSpec> <setSpec>collection:B3ESTE</setSpec> <setSpec>collection:UNIV-MONTPELLIER</setSpec> </header> <metadata><dc> <publisher>HAL CCSD</publisher> <title lang=en>Seismic anisotropy and shear-wave splitting in lower-crustal and upper-mantle rocks from the Ivrea Zone : experimental and calculated data</title> <creator>Barruol, Guilhem</creator> <creator>Kern, Hartmut</creator> <contributor>Laboratoire de Tectonophysique (Tectonophysique) ; Université Montpellier 2 - Sciences et Techniques (UM2) - 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> <contributor>Institute of Geosciences, University of Kiel, Kiel 24118, Germany ; </contributor> <description>International audience</description> <source>ISSN: 0031-9201</source> <source>EISSN: 0031-9201</source> <source>Physics of the Earth and Planetary Interiors</source> <publisher>Elsevier</publisher> <identifier>hal-01389712</identifier> <identifier>http://hal.univ-reunion.fr/hal-01389712</identifier> <identifier>http://hal.univ-reunion.fr/hal-01389712/document</identifier> <identifier>http://hal.univ-reunion.fr/hal-01389712/file/Barruol_Kern-PEPI96_hal.pdf</identifier> <source>http://hal.univ-reunion.fr/hal-01389712</source> <source>Physics of the Earth and Planetary Interiors, Elsevier, 1996, 95, pp.175 - 194. 〈10.1016/0031-9201(95)03124-3〉</source> <identifier>DOI : 10.1016/0031-9201(95)03124-3</identifier> <relation>info:eu-repo/semantics/altIdentifier/doi/10.1016/0031-9201(95)03124-3</relation> <language>en</language> <subject>[SDU.STU.GP] Sciences of the Universe [physics]/Earth Sciences/Geophysics [physics.geo-ph]</subject> <type>info:eu-repo/semantics/article</type> <type>Journal articles</type> <description lang=en>To quantify the relationships between anisotropy. S-wave splitting and tectonics, we determined the seismic properties of lower-crustal and upper-mantle rocks outcropping in the lvrea Zone (Northem Italy). We obtained P-and S-wave seismic velocities by laboratory direct velocity measurements and/or by calculations based on the modal compositions of the rocks, the lattice preferred orientations (LPOs), and the single crystal stiffness coefficients. Measured P-and S-wave velocities (6.0-7 .5 km s-1 and 3.6-4.2 km s-1) are typical of the lower crust. The P-wave anisotropy is in the range 0-l 0%. Shear-wave birefringence is in the range 0.0-0.6 km s-1 , with typical values between 0.0 and 0.2 km s-1 • In many cases, the birefringence is clearly related to fabric elements (foliation, lineation). Mafic rocks such as anorthosite or pyroxene-bearing gabbros exhibit low P-wave anisotropies (< 5%) and low shear-wave birefringences (less than 0.1 km s-1). In contrast, the seismic properties of felsic rocks such as biotite-bearing gneisses and mafic rocks such as amphibolites display high V P anisotropy (10%) and strong birefringence (0.3 km s-1). Biotite and amphibole preferred orientations clearly control seismic anisotropy and particularly shear-wave splitting. In these rocks, maximum splitting is observed in directions parallel to the foliation with the fast split shear wave polarized parallel to the foliation plane. To have an overview of the seismic properties of this lower-crustal section at a broader scale, we calculated from our data the anisotropie seismic properties of several hypothetical samples that are perhaps more representative of the regional anisotropy than each sample individually. For instance, the average lower-crustal sample displays an anisotropy of 5.5% for P waves and a birefringence around 0.14 km s I for S waves propagating parallel to the foliation. We observe little splitting for waves propagating at high angle to the foliation.</description> <date>1996</date> </dc> </metadata> </record> </GetRecord> </OAI-PMH>