Melting phase equilibrium relations in the MgSiO3-SiO2 system under high pressures

Takuya Moriguti, Yuusuke Yachi, Akira Yoneda, Eiji Ito

Research output: Contribution to journalArticlepeer-review

Abstract

Melting relations in the MgSiO3-SiO2 system have been investigated at 13.5 GPa using a Kawai-type multi-anvil apparatus. The system displays eutectic melting with the eutectic point located at SiO2/(SiO2+MgO) = 0.61 (in mol; which is denoted by XSi hereafter) and at 2350 ± 50 °C. Taking into account the eutectic compositions at lower pressures reported in previous studies, i.e., 0.556 at 1 GPa (Hudon et al. 2005) and 0.60 at 5 GPa (Dalton and Presnall 1997), the eutectic composition is slightly enriched in SiO2 with increasing pressure. The silica-rich eutectic composition is not consistent with the present peridotitic mantle composition (XSi = 0.43). Considering Si incorporation into iron alloys in a magma ocean, however, mass-balance calculations based on an E-chondrite model demonstrate that the silicate magma ocean could have XSi consistent with the present peridotitic mantle.

Original languageEnglish
Pages (from-to)2226-2233
Number of pages8
JournalAmerican Mineralogist
Volume107
Issue number12
DOIs
Publication statusPublished - Dec 1 2022

Keywords

  • enstatite chondrite model
  • high pressure
  • mantle
  • Melting
  • MgSiO-SiO system
  • multianvil
  • pressure calibration
  • thermal expansion

ASJC Scopus subject areas

  • Geophysics
  • Geochemistry and Petrology

Fingerprint

Dive into the research topics of 'Melting phase equilibrium relations in the MgSiO3-SiO2 system under high pressures'. Together they form a unique fingerprint.

Cite this