Permalink :  http://hdl.handle.net/2115/36778

Partition coefficients of Mn2+, Fe2+, Co2+, Ni2+ and Zn2+ between olivine and silicate melt have been determined in the system Mg2SiO4-SiO2-H2O at high pressure and temperature. A partition coefficient is defined by the ratio of the concentration of an element in olivine to that of the element in silicate melt. Olivine has two octahedral sites (M1 and M2 sites). Elements are partitioned among an M1, an M2 sites and silicate melt. We distributed the bulk concentration of the element in olivine to that in the M1 and M2 sites with olivine using the intracrystalline cation distribution data. Partition coefficients between an M1 site and silicate melt, and between an M2 site and silicate melt are shown in a PC-IR (partition coefficient versus ionic radius) diagram. The partition coefficient of Zn2+ is exceptionally apart from a linear relationship that those of other elements show. However, a linear relationship is completed, including the partition coefficient of Zn2+, in a PC-MO (a partition coefficient versus a metal oxygen distance) diagram. M-O distances are the parameter which show the characteristic of both an ionic and a covalent bonding of elements.

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