Olivine trace elements

Jones JH (1995) Experimental trace element partitioning. In Ahrens TJ (ed) Rock physics and phase relations A handbook of physical constants Am Geophys Union Reference Shelf 3 73-104 Kennedy AK, Lofgren GE, Wasserburg GJ (1993) An experimental study of trace element partitioning between olivine orthopyroxene and melt in chondrales equilibrium values and kinetic effects. Earth Planet Sci Lett 115 177-195... 

Taura H, Yurimoto H, Kurita K, Sueno S (1998) Pressure dependence on partition coefficients for trace elements between olivine and the coexisting melts. Phys Chem Min 25 469-484 Taura H, Yurimoto H, Kato T, Sueno S (2001) Trace element partitioning between silicate perovskites and ultracalcic melt. Phys Planet Earth Int 124 25-32... 

This form of the partition coefficient, analogous to that used for Fe-Mg fractionation between olivine and melt (see Chapter 1), is necessary only for the rare cases where trace substitution affects Cj and Cp substantially. A number of reviews (O Nions and Powell, 1977 Michard, 1989) describe the various sorts of partition coefficients expressed either in mass-fractions, atom fractions, or normalized to a major element and their respective merits. If the discussion is restricted to a narrow range of chemical compositions (e.g., basaltic systems, Irving, 1978, Irving and Frey, 1984), enough experimental information exists on trace-element partitioning to resort to the wonderfully simple equation (9.1.1). 

Bird M. L. (1971). Distribution of trace elements in olivines and pyroxenes An experimental study. Ph.D. diss., University of Missouri, Rolla. 

When the concentration levels are higher, such as Ni diffusion between two olivine crystals with the same compositions except for Ni content (e.g., one contains 100 ppm and the other contains 2000 ppm), it may be referred to as either tracer diffusion or chemical diffusion. Tracer diffusivity is constant across the whole profile because the only variation along the profile is the concentration of a trace element that is not expected to affect the diffusion coefficient. 

Although scattered, major and trace element variations for the Vulsini rocks define overall trends that support an evolution dominated by fractional crystallisation starting from different types of parental melts. Holm et al. (1982) suggested that the evolution of HKS magmas was dominated by fractional crystallisation with separation of olivine and clinopyroxene in the mafic range, and of variable proportions of clinopyroxene, leucite, pla-... 

Fractional crystallisation has been dominated by separation of various proportions of clinopyroxene and olivine in the mafic magmas, and of cli-nopyroxene and feldspars in the felsic melts. These generated decrease in ferromagnesian elements (FeO, MgO, Ni, Co, Cr, etc.) and increase in incompatible elements (e.g. Th, Ta, Nb, REE), with ongoing evolution. In contrast, ratios of incompatible trace elements were not affected by fractionation processes, and can be used to infer compositions of mantle-equilibrated melts. 

Calc-alkaline rocks at Stromboli have lower K20, P2O5 and incompatible trace element contents than the associated shoshonitic and KS rocks. However, REE and the mantle-normalised incompatible element patterns have similar shapes for all rocks, with positive spikes of Ba and negative anomalies of HFSE (Fig. 7.14). Glass inclusions with primitive compositions (MgO 7.8 wt %) contained in olivine (F091-84) from basaltic scoriae of the present-day activity, have the same type of incompatible element patterns as the whole rocks (Bertagnini et al. 2003). Sr-isotope ratios are... 

Colsen, R. O., McKay, G. A. Taylor, L. A. (1988) Temperature and composition dependencies of trace element partitioning Olivine/melt and low-Ca pyroxene/melt. Geochim. Cosmochim. Acta, 52, 539-53. 

Taftp, J. Spence, J. C. H. (1982) Crystal lattice location of iron and trace elements in a magnesium-iron olivine by a new crystallographic technique. Science, 218, 49-51. 

Dale and Henderson (1972) investigated trace element distribution in phenocrysts (olivine, pyroxene) and basalt matrix, with much consideration of crystal field effects. Banno and Matsui (1973) published a new formulation of partition coefficients for trace element distribution between minerals and magmas, based on the concept of chemical potentials for liquids and crystals. 

Grossman L., Ganapathy R., Methot R. L., and Davis A. M. (1979) Trace elements in the AUende meteorite amoeboid olivine aggregates. Geochim. Cosmochim. Acta 43, 817-829. 

There are very few bulk analyses for coarsegrained olivine clasts from mesosiderites, and observed distinctions between them and pallasite olivines are mostly due to chromite and metal inclusions in the former (Mittlefehldt, 1980). Orthopyroxene clasts are generally similar to diogenites in major-, minor-, and trace-element composition (see Mittlefehldt et al., 1998). 

Kennedy A. K., Lofgren G. E., and Wasserburg G. J. (1993) An experimental study of trace element partitioning between olivine, orthopyroxene, and melt in chondrules. Earth Planet. Sci. Lett. 115, 177-195. 

Most trace elements have values of D< C 1, simply because they differ substantially either in ionic radius or ionic charge, or both, from the atoms of the major elements they replace in the crystal lattice. Because of this, they are called incompatible. Exceptions are trace elements such as strontium in plagioclase, ytterbium, lutetium, and scandium in garnet, nickel in olivine, and scandium in clinopyroxene. These latter elements acmally fit into their host crystal structures slightly better than the major elements they replace, and they are therefore called compatible. Thus, most chemical elements of the periodic table are trace elements, and most of them are incompatible only a handful are compatible. 

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