Experimental determination of equilibrium nickel isotope fractionation between metal and silicate from 500°C to 950°C

The Isotope Geochemistry of Ni

“…Most plausibly this is the result of core formation, as Ni is a siderophile element and strongly partitioned into the metal phase. The sense of isotopic fractionation between the silicate Earth and chondrites is consistent with the isotope partitioning 610 experiments of Lazar et al (2012), who determined a fractionation factor between metal and talc, Δ 62/58 Ni metal-silicate = (0.25±0.02)x10 6 /T 2 . Using this expression to calculate isotopic fractionation between metal and silicate during core formation predicts a rather more modest than observed difference between bulk and silicate Earth of ~0.02 ‰ for a single core-mantle equilibrium at 2500 K. Yet, as the authors note, larger net fractionations are possible for a Rayleigh process 615 with a well mixed mantle magma ocean.…”

“…As discussed above, there is currently only a single experiment to underpin understanding of the controls on Ni isotopic fractionation at magmatic temperatures (Lazar et al, 2012). In contrast, isotopic fractionations between Ni species relevant for the hydrological cycle have received more extensive, theoretical investigation (Fujii et al 2011;Fujii et al 2014).…”

Isotope Fractionation Processes of Selected Elements

“…To investigate potential Ni isotope fractionation between core and mantle, Lazar et al (2012) determined Ni isotope fractionations between Ni metal and Ni talc silicate. Since the metal has been found to be enriched in the light Ni isotopes, they suggested that Ni isotope fractionations might have occurred during Earth's core segregation.…”

Development of an isolation procedure and MC-ICP-MS measurement protocol for the study of stable isotope ratio variations of nickel

“…As an abundant element in the Solar System, Ni is present in sufficiently high concentrations in most meteorites. [8][9][10][11] A comparative study of the effect of mass-dependent isotope fractionation observed for Ni in genetically related meteorite fractions could not only show a correlation with the concentration of particular major elements (e.g., P, S), but also with the cooling rate of the meteorite and/or the isotopic composition of other fractionated elements (e.g., O, Cr). E-mail: Frank.Vanhaecke@UGent.be b Vrije Universiteit Brussel, Earth System Sciences, Pleinlaan 2, 1050 Brussels, Belgium isotopes during evaporation/condensation, core formation, and magmatic processes.…”