Olivine rare earth elements

Michael PJ (1988) Partition coefficients for rare earth elements in mafic minerals of high silica rhyohtes the importance of accessory mineral inclusions. Geochim Cosmochim Acta 52 275-282 Mysen BO (1979) Nickel partitioning between olivine and silicate melt Henry s Law revisited. Am Mineral 64 1107-1114... 

For small extents of crystallization, the maximum change, and thereby the most valuable information on F, will be obtained from elements with high Dt (compatible elements) such as Ni in basaltic olivine. Elements with ), 1 (incompatible elements), such as Th, Ba or rare-earth elements in basaltic systems, will provide basically no clue to F variations. In addition, information carried by incompatible elements, which do not fractionate with respect to each other, is entirely redundant. This is better shown by taking the relative change in the ratio of two elements il and i2 per increment of crystallization... 

In this section, we discuss the question of the bulk planetary abundances of the rare earth elements. Central to the problem of planetary abundance determinations is the assumption that the composition of the original solar nebula, for the non-gaseous elements, is given by the composition of the Cl meteorites. It is accordingly of interest to see what evidence is available from the planets, and how it relates to the primordial nebula values. In the previous section, we have seen that although the moon is enriched in the lanthanides relative to those in the primordial solar nebula by about 2.5 times, the pattern is probably parallel to that of Cl. The evidence for an apparent depletion in the heavy lanthanides is readily explicable as a consequence of early lunar magma ocean crystallisation of phases such as olivine and orthopyroxene, which selectively accept Gd-Lu. 

Diffusion of rare earth elements was characterized in natural olivine under dry conditions. Samples were aimealed at 850 to 1300C, and diffusant distributions were profiled using Rutherford back-scattering spectrometry. The Arrhenius relationship... 

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