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dc.rights.licenseopenen_US
hal.structure.identifierLaboratoire d'Océanographie et du Climat : Expérimentations et Approches Numériques [LOCEAN]
dc.contributor.authorMORENO, Eva
hal.structure.identifierLaboratoire d’Océanologie et de Géosciences (LOG) - UMR 8187 [LOG]
dc.contributor.authorCAROIR, Fabien
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorFOURNIER, Léa
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorFAUQUEMBERGUE, Kelly
hal.structure.identifierEnvironnements et Paléoenvironnements OCéaniques [EPOC]
dc.contributor.authorZARAGOSI, Sébastien
hal.structure.identifierGéosciences Paris Saclay [GEOPS]
dc.contributor.authorJOUSSAIN, Ronan
hal.structure.identifierGéosciences Paris Saclay [GEOPS]
dc.contributor.authorCOLIN, Christophe
hal.structure.identifierCentre de Recherche en Paléontologie - Paris [CR2P]
dc.contributor.authorBLANC-VALLERON, Marie-Madeleine
hal.structure.identifierInstitut des Sciences de la Terre de Paris [iSTeP]
dc.contributor.authorBAUDIN, François
hal.structure.identifierCentre européen de recherche et d'enseignement des géosciences de l'environnement [CEREGE]
dc.contributor.authorDE GARIDEL-THORON, Thibault
hal.structure.identifierInstitut de Physique du Globe de Paris [IPGP (UMR_7154)]
dc.contributor.authorVALET, Jean-Pierre
hal.structure.identifierPaléocéanographie [PALEOCEAN]
dc.contributor.authorBASSINOT, Franck
dc.date.accessioned2024-01-29T11:16:14Z
dc.date.available2024-01-29T11:16:14Z
dc.date.issued2020-12
dc.identifier.issn0025-3227en_US
dc.identifier.urihttps://oskar-bordeaux.fr/handle/20.500.12278/187586
dc.description.abstractEnWe present here a study based on the Anisotropy of Magnetic Susceptibility (AMS) and magnetic mineralogy carried out on the composite core MD17&18taken from the eastern levee of the active channel of the middle Bengal Fan in the Indian Ocean. Based on C-14 dating, the sedimentary sequence covers 9.8 ka in 39 m of sediment. It therefore records at very high resolution the variations in continental material exported to the ocean by the Ganges-Brahmaputra river system during the Holocene.This sequence was divided into two units according to turbidite activity: Unit 1 from 9.8 to 9.2 ka cal. BP representing 39 m of coarse-grained turbidite sequences (coarse silts to fine sands) and extremely high sedimentation rates. Unit 2 of 9.2 ka cal. BP to the present characterized by a sharp decrease in the sedimentation rate, the presence of fine-grained turbidites characterized by strong decrease in the ln(Ti/Ca) ratio.Our AMS results indicate that the magnetic fabric is highly sensitive to the mode of deposition. The turbidite sequences are clearly characterized by very high F and Pj values, not only of the coarse-grained turbidite levels in unit 1, but also of the fine turbidites in unit 2. We suggest that this strong degree of anisotropy is the result of the strong and rapid deposition during the turbidite sequences which induces an additional compaction effect.Furthermore, low temperature SIRM measurements revealed that the magnetic minerals representative of the Ganges and Brahmaputra drainage area are magnetite, hematite and goethite. A higher supply in fine-grained magnetite was observed during the turbidite sequences in phase with an increase in sediment grain size.
dc.description.sponsorshipPaléo-variabilité de la mousson indienne - ANR-11-BS56-0024en_US
dc.language.isoENen_US
dc.subject.enBengal fan
dc.subject.enHolocene
dc.subject.enturbidite activity
dc.subject.enmagnetic fabric
dc.subject.enmagnetic mineralogy
dc.title.enMagnetic fabric of Bengal fan sediments: Holocene record of sedimentary processes and turbidite activity from the Ganges-Brahmaputra river system
dc.typeArticle de revueen_US
dc.identifier.doi10.1016/j.margeo.2020.106347en_US
dc.subject.halPlanète et Univers [physics]/Océan, Atmosphèreen_US
dc.subject.halPlanète et Univers [physics]/Interfaces continentales, environnementen_US
bordeaux.journalMarine Geologyen_US
bordeaux.page106347en_US
bordeaux.volume430en_US
bordeaux.hal.laboratoriesEPOC : Environnements et Paléoenvironnements Océaniques et Continentaux - UMR 5805en_US
bordeaux.institutionUniversité de Bordeauxen_US
bordeaux.institutionCNRSen_US
bordeaux.teamSEDIMen_US
bordeaux.peerReviewedouien_US
bordeaux.inpressnonen_US
bordeaux.import.sourcehal
hal.identifierhal-02970912
hal.version1
hal.popularnonen_US
hal.audienceInternationaleen_US
hal.exportfalse
workflow.import.sourcehal
dc.rights.ccPas de Licence CCen_US
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