Horizon / Plein textes La base de ressources documentaires de l'IRD


Publications des scientifiques de l'IRD

Poitrasson Franck, Delpech G., Grégoire Michel. (2013). On the iron isotope heterogeneity of lithospheric mantle xenoliths : implications for mantle metasomatism, the origin of basalts and the iron isotope composition of the Earth. Contributions to Mineralogy and Petrology, 165 (6), 1243-1258. ISSN 0010-7999

Accès réservé (Intranet IRD) Document en accès réservé (Intranet IRD)

Lien direct chez l'éditeur doi:10.1007/s00410-013-0856-7

On the iron isotope heterogeneity of lithospheric mantle xenoliths : implications for mantle metasomatism, the origin of basalts and the iron isotope composition of the Earth
Année de publication2013
Type de documentArticle référencé dans le Web of Science WOS:000319009600011
AuteursPoitrasson Franck, Delpech G., Grégoire Michel.
SourceContributions to Mineralogy and Petrology, 2013, 165 (6), p. 1243-1258. ISSN 0010-7999
RésuméWith the aim to better understand the cause of the iron isotope heterogeneity of mantle-derived bulk peridotites, we compared the petrological, geochemical and iron isotope composition of four xenolith suites from different geodynamic settings; sub-arc mantle (Patagonia); subcontinental lithospheric mantle (Cameroon), oceanic mantle (Kerguelen) and cratonic mantle (South Africa). Although correlations were not easy to obtain and remain scattered because these rocks record successive geological events, those found between delta Fe-57, Mg#, some major and trace element contents of rocks and minerals highlight the processes responsible for the Fe isotope heterogeneity. While partial melting processes only account for moderate Fe isotope variations in the mantle (< 0.2 aEuro degrees, with bulk rock values yielding a range of delta Fe-57 +/- A 0.1 aEuro degrees relative to IRMM-14), the main cause of Fe isotope heterogeneity is metasomatism (> 0.9 aEuro degrees). The kinetic nature of rapid metasomatic exchanges between low viscosity melts/fluids and their wall-rocks peridotite in the mantle is the likely explanation for this large range. There are a variety of responses of Fe isotope signatures depending on the nature of the metasomatic processes, allowing for a more detailed study of metasomatism in the mantle with Fe isotopes. The current database on the iron isotope composition of peridotite xenoliths and mafic eruptive rocks highlights that most basalts have their main source deeper than the lithospheric mantle. Finally, it is concluded that due to a complex geological history, Fe isotope compositions of mantle xenoliths are too scattered to define a mean isotopic composition with enough accuracy to assess whether the bulk silicate Earth has a mean delta Fe-57 that is chondritic, or if it is similar to 0.1 aEuro degrees above chondrites as initially proposed.
Plan de classementGéologie et formations superficielles [064]
LocalisationFonds IRD [F B010060350]
Identifiant IRDfdi:010060350
Lien permanenthttp://www.documentation.ird.fr/hor/fdi:010060350

Export des données

Disponibilité des documents

Télechargment fichier PDF téléchargeable

Lien sur le Web lien chez l'éditeur

Accès réservé en accès réservé

HAL en libre accès sur HAL

Accès aux documents originaux :

Le FDI est labellisé CollEx

Accès direct

Bureau du chercheur

Site de la documentation

Espace intranet IST (accès réservé)

Suivi des publications IRD (accès réservé)

Mentions légales

Services Horizon

Poser une question

Consulter l'aide en ligne

Déposer une publication (accès réservé)

S'abonner au flux RSS

Voir les tableaux chronologiques et thématiques

Centres de documentation


Montpellier (centre IRD)

Montpellier (MSE)






La Paz