A genetic metasomatic link between eclogitic and peridotitic diamond inclusions
MetadataShow full item record
Diamond inclusions sample the otherwise inaccessible archive of Earth’s deep interior. The geochemical and petrological diversity of diamond inclusions reflects either pre-metasomatic upper mantle heterogeneity or metasomatism coeval with diamond formation. We focus on the origin of lithospheric garnet and clinopyroxene inclusions by simulating metasomatic reactions between eclogitic fluids and mantle peridotites at 5 GPa, 1000 °C, and across a range of redox conditions (logfO2 = −1 to −6 ΔFMQ). Our results demonstrate that fluid-rock interaction can result in the formation of eclogitic, websteritic, and peridotitic silicates from a single fluid during a single diamond-forming metasomatic event. Ergo, the petrogenesis of diamond and their inclusions can be syngenetic, and the petrological diversity of diamond inclusions can reflect metasomatism coeval with diamond formation. Furthermore, during the metasomatism, refractory peridotite can be converted to fertile websterite which could become a pyroxenitic mantle source for oceanic basalts.
Mikhail , S , Rinaldi , M , Mare , E R & Sverjensky , D 2021 , ' A genetic metasomatic link between eclogitic and peridotitic diamond inclusions ' , Geochemical Perspectives Letters , vol. 17 , pp. 33-38 . https://doi.org/10.7185/geochemlet.2111
Geochemical Perspectives Letters
Copyright © 2021 The Authors. Open Access. This work is distributed under the Creative Commons Attribution Non-Commercial No-Derivatives 4.0 License, which permits unrestricted distribution provided the original author and source are credited. The material may not be adapted (remixed, transformed or built upon) or used for commercial purposes without written permission from the author. Additional information is available at https://www.geochemicalperspectivesletters.org/copyright-and-permissions.
DescriptionFunding for SM, ERM, and MR is provided by NERC standard grant (NE/P012167/1) and UK Space Agency Aurora grant (ST/T001763/1). Funding for DAS is provided by the US DOE (DE-FG-02-96ER-14616) and the US NSF (EAR 1624325 and ACI 1550346).
Items in the St Andrews Research Repository are protected by copyright, with all rights reserved, unless otherwise indicated.