High pressure and high temperature metal-silicate partitioning of siderophile elements: The importance of silicate liquid composition

Metal–silicate partitioning of tungsten at high pressure and temperature: Implications for equilibrium core formation in Earth

“…(3) accounts for 96% of the variance observed in the C-free data and 95% when the 1/T term is excluded. This is a testament to the strong systematic control that oxygen fugacity and melt structure exert on W partitioning, confirming the affinity of W for more depolymerized melts Hillgren et al, 1996;Jana and Walker, 1997b) and more oxidized melts (Schmitt et al, 1989;Ertel et al, 1996; Jaeger and Drake, 2000).…”

“…7. Iron-alloy/silicate partitioning data for W as a function of melt composition and oxygen fugacity from the literature (Ertel et al, 1996;Hillgren et al, 1996;Jana and Walker, 1997a,b;1997cRighter and Drake, 1999;Righter and Shearer, 2003) and this study (with the exception of Schmitt et al, 1989 for which molar Ds could not be reconstructed because an unknown amount of radioactive W tracer was added to the experiments., Palme, pers. comm.…”

Solubility of palladium in picritic melts: 1. The effect of iron

“…(1), may no longer be valid, and that we see the activity of Pd n+ increasing at a rate faster than Pd n+ solubility. Mysen et al (1982) showed that Fe 3+ tends to polymerize silicate melts, and Hillgren et al (1996) demonstrated experimentally that solubilities of transition metals tend to decrease when silicate melts polymerize. Hence, for the highly oxidized segment in Fig.…”

“…However, many authors regard this system to be too simplistic (e.g. Hillgren et al, 1996;O'Neill and Eggins, 2002;Rose-Weston et al, 2009) and melt composition (i.e. CaO, MgO, FeO or S concentrations, degree of polymerization) has been shown to be an important factor for the solubility of trace elements in silicate melts at sulfide-undersaturated conditions.…”

Conditions of core formation in the earth: Constraints from Nickel and Cobalt partitioning

“…3; using our experimental pressure of 7 GPa and the weighted averages of C 2 calculated from the pressure studies on Figure 5, the value of C 1 for both D(Ni) and D(Co), and the associated error, were calculated. The last constant, C 3 , was calculated by averaging the values of C 3 determined by each of our experiments as well as from all of the appropriate experiments of previous studies (Hillgren et al, 1994(Hillgren et al, , 1996Thibault and Walter, 1995;Ohtani et al, 1997;Righter et al, 1997;Walker, 1997a, 1997c;Ito et al, 1998;Gessmann and Rubie, 1998;Bouhifd and Jephcoat, 2003). By including all available experimental data, any minor effects from differences in silicate and metallic compositions or any systematic error in a given data set were minimized in the final parameterizations.…”