Partitioning of iron and magnesium between crystals and partial melts in peridotite upper mantle

✍ Scribed by Bjørn Mysen

• Publisher: Springer
• Year: 1975
• Tongue: English
• Weight: 503 KB
• Volume: 52
• Category: Article
• ISSN: 0010-7999
• DOI: 10.1007/bf00395005

✦ Synopsis

The iron-magnesium distribution coefficient, K, (v /v "~olivine [~,.-/y "~liquid D = ~,ZXZFeO/ZXMgO] ~/XMgO/~'~EFeO/ ,

has frequently been used as a means of testing whether experimental and natural silicate liquids could have been in equilibrium with olivine of mantle composition. It is shown here that this K o decreases with increasing oxygen fugacity (fo2) for a hydrous partial melt in equilibrium with a natural spinel peridotite assemblage under pressure and temperature conditions corresponding to those of the upper mantle (from 0.52 at the fo~ of the iron-wtistite buffer to 0.04 at the fo2 of the magnetite-hematite buffer). K; also increases with increasing pressure, with decreasing temperature, and probably with increasing Mg/(Mg +Z Fe) of the parental peridotite, suggesting that K D = (XFe#/MgO) ~ (XMgO/XFeo) liquid