The Subantarctic lithospheric mantle

• Published in: Geological Society, London, Memoirs
• Main Authors: Delpech, Guillaume, Scott, James, Grégoire, Michel, Moine, Bertrand N., Li, Dongxu, Liu, Jingao, Pearson, D. Graham, van Der Meer, Quinten, Waight, Tod, Michon, Gilbert, Guillaume, Damien, O'Reilly, Suzanne, Cottin, Jean-Yves, Giret, André
• Other Authors: Géosciences Paris Saclay (GEOPS), Institut national des sciences de l'Univers (INSU - CNRS)-Université Paris-Saclay-Centre National de la Recherche Scientifique (CNRS), Géosciences Environnement Toulouse (GET), Institut de Recherche pour le Développement (IRD)-Université Toulouse III - Paul Sabatier (UT3), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Observatoire Midi-Pyrénées (OMP), Université Fédérale Toulouse Midi-Pyrénées-Université Fédérale Toulouse Midi-Pyrénées-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Institut de Recherche pour le Développement (IRD)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National d'Études Spatiales Toulouse (CNES)-Centre National de la Recherche Scientifique (CNRS)-Météo-France -Centre National de la Recherche Scientifique (CNRS), Laboratoire Magmas et Volcans (LMV), Institut national des sciences de l'Univers (INSU - CNRS)-Institut de Recherche pour le Développement et la société-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Observatoire de Physique du Globe de Clermont-Ferrand (OPGC), Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)-Institut national des sciences de l'Univers (INSU - CNRS)-Centre National de la Recherche Scientifique (CNRS)-Université Clermont Auvergne (UCA)
• Format: Book Part
• Language: English
• Published: HAL CCSD 2021
• Subjects: [SDU]Sciences of the Universe [physics]; Antarctic; The Antarctic; Kerguelen; Kerguelen Islands; Pacific; Indian; Antarc*; Auckland Islands
• Online Access: https://hal.science/hal-03266963; https://hal.science/hal-03266963/document; https://hal.science/hal-03266963/file/Geol_SocL_2021.pdf; https://doi.org/10.1144/M56-2020-13

International audience We present a summary of peridotite in the Subantarctic (46 to 60°S) surrounding the Antarctic Plate. Peridotite xenoliths occur on Kerguelen and Auckland islands. Kerguelen islands are underlain by a plume whereas the Auckland Islands are part of continental Zealandia, which is a Gondwana-rifted fragment. Small amounts of serpentinised peridotite has been dredged from fracture zones on the Southeast Indian, Southwest Indian, and Pacific Antarctic Ridge, and represents upwelled asthenosphere accreted to form lithosphere. Supra-subduction zone peridotite has been collected from two locations on the Sandwich Plate. Peridotites from most Subantarctic occurrences are moderately to highly depleted, and many show signs of subsequent metasomatic enrichment. Os isotopes indicate that the Subantarctic continental and oceanic lithospheric mantle contains ancient fragments that underwent depletion long before formation of the overlying crust.