Subduction-related oxidation of the sublithospheric mantle evidenced by ferropericlase and magnesiowustite diamond inclusions.

ABSTRACT: Ferropericlase (Mg,Fe)O is the second most abundant mineral in Earth's lower mantle and a common inclusion found in subcratonic diamonds. Pyrolitic mantle has Mg# (100 × Mg/(Mg+Fe)) ~89. However, ferropericlase inclusions in diamonds show a broad range of Mg# between 12 and 93. Here we use Synchrotron Mössbauer Source (SMS) spectroscopy and single-crystal X-ray diffraction to determine the iron oxidation state and structure of two magnesiowüstite and three ferropericlase inclusions in diamonds from São Luiz, Brazil. Inclusion Mg#s vary between 16.1 and 84.5. Ferropericlase inclusions contain no ferric iron within the detection limit of SMS, while both magnesiowüstite inclusions show the presence of monocrystalline magnesioferrite ((Mg,Fe)Fe³⁺₂O₄) with an es

SUBMITTER: Kiseeva ES 

PROVIDER: S-EPMC9726884 | biostudies-literature | 2022 Dec

REPOSITORIES: biostudies-literature