Experiments on the partitioning of Mg~(2+), Ca~(2+), Mn~(2+), Fe~(2+), Co~(2+), Ni~(2+) and Zn~(2+) between olivine (forsterite and fayalite) and 2 N aqueous chloride solutions were performed in the temperature range of 500 to 800 deg C, 1 kb.The partition coefficient, which is defined as K_(PN)(Fo)=(X_(Me_2SiO_4)/ X_(Mg_2SiO_4))/(m_(MeCl_(2aq))/m_(MgCl_(2aq))) or K_(PN)(Fa) = (X_(Me_2SiO_4)/X_(Fe_2Cl_(2aq)) vs. ionic radius (PC-IR) diagrams are drawn based on the experimental results. In the case of forsterite, the PC-IR curve has a local maximum near Ni~(2+) and shows a concave curve in the region of larger ionic size. However Zn~(2+) deviates from such a trend. In the case of fayalite, the PC-IR curve shows a convex curve with a peak near Ni~(2+) except for 500 deg C. Also in this case, Zn~(2+) deviates from such a trend. The anomaly of Zn~(2+) may be attributable to its tetrahedral site preferency. The K_(PN) value for Ni~(2+) decreases with increasing temperature, whereas those for the other elements except for Ca~(2+) increase. The optimum ionic radius for forsterite and fayalite seem to increase slightly with increasing temperature.
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