Zircon partition coefficient

LaTourette, T. Z., and D. S. Burnett, Fe-Ti oxide and zircon partition coefficients for uranium in silica-rich liquid from partially melted granitic blocks erupted at Mt. Mazama (Crater Lake), Oregon (abstract), Eos Trans. AGU, 70, 1403, 1989. 

There are surprisingly few microbeam studies of zircon-melt partitioning in natural systems and none in experimental systems. Recently Thomas et al. (2002) have derived zircon-melt partition coefficients from rehomogenised glass inclusions in zircons from an intrusive tonalite, while Hinton et al. (R. Hinton, S. Marshall and R. Macdonald, written comm.) have used an ion-microprobe to measure zircon-melt partition coefficients from a Kenyan peralkaline rhyolite, with an estimated eruption temperature of 700°C (Scaillet and Macdonald 2001). We have used the lanthanide partition coefficients from these two studies to derive best-fit values for and for the large Vlll-co-ordinated site. In total there are 13 individual sets of partition coefficients. All of these yield broadly consistent values of, in the range 0.968-1.018 A, but very variable, in the range 373-1575 GPa. Because Lu is comparable in size to cannot be well... 

Figure 24. Lattice strain model applied to zircon-melt partition coefficients from Hinton et al. (written comm.) for a zircon phenocryst in peralkaline rhyolite SMN59 from Kenya. Ionic radii are for Vlll-fold coordination (Shannon 1976). The curves are fits to Equation (1) at an estimated eraption temperature of 700°C (Scaillet and Macdonald 2001). Note the excellent fit of the trivalent lanAanides, with the exception of Ce, whose elevated partition coefficient is due to the presence of both Ce and Ce" in the melt, with the latter having a much higher partition coefficient into zircon. The 4+ parabola cradely fits the data from Dj, and Dy, through Dzi to Dih, but does not reproduce the observed DuIDjh ratio. We speculate that this is due to melt compositional effects on Dzt and (Linnen and Keppler 2002), and possibly other 4+ cations, in very silicic melts. Because of its Vlll-fold ionic radius of 0.91 A (vertical line), Dpa is likely to be at least as high as Dwh, and probably considerably higher.

Thomas JB, Bodnar RJ, Shimizu N, Sinha AK (2002) Determination of zircon/melt trace element partition coefficients from SIMS analysis of melt inclusions in zircon. Geochim Cosmochim Acta 66 2887-2901 Thompson GM, Malpas J (2000) Mineral/melt partition coefficients of oceanic alkali basalts determined on natural samples using laser ablation-inductively eouple plasma-mass spectrometry (LAM-ICP-MS). Mineral Mag 64 85-94... 

Compatible element An element with equilibrium solid/melt partition coefficient >1. In garnet (and zircon), heavy REE, scandium, vanadium, and yttrium are compatible. These elements are incompatible in all other rock-forming minerals involved in igneous fractionation processes discussed in this chapter. 

Fowler SW, Buat-Menard P, Yokoyama Y, Ballestra S, Holm E, Van Nguyen H (1987) Rapid removal of Chernobyl fallout from Mediterranean sttrface waters by biological activity. Nature 335 622-625 Fujimaki H (1986) Partition coefficients of Hf, Zr, and REE between zircon, apatite, and liquid. Contrib Mineral Petrol 94 42-45... 

Fujimaki H., 1986, Partition coefficients of Hf, Zr and REE between zircon, apatite and liquid. Contrib. Mineral. Petrol., 94, 42-45. 

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