Trace elements garnets

Green TH, Blundy JD, Adam J, Yaxley GM (2000) SIMS determination of trace element partition coefficients between garnet clinopyroxene and hydrous basaltic liquids at 2-7.5 GPa and 1080-1200°C. Lithos 53 165-187... 

Guo J, Green TH (1990) Experimental study of barium partitioning between phlogopite and sihcate liquid at upper-mantle pressure and temperature. Lithos 24 83-96 Harrison WJ, Wood BJ (1980) An experimental investigation of the partitioning of REE between garnet and liquid with reference to the role of defects. Contrib Mineral Petrol 72 145-155 Hart SR, Duim T (1993) Experimental cpx/melt partitioning of 24 trace elements. Contrib Mineral Petrol 113 1-8... 

Hauri EH, Wagner TP, Grove TL (1994) Experimental and natural partitioning of Th U Pb and other trace elements between garnet clinopyroxene and basaltic melts. Chem Geol 117 149-166 Hazen RM, Finger LW (1979) Bulk Modulus-volume relationship for cation-anion polyhedra. J Geophys Res 84 6723-6728... 

Harrison W. J. (1977). An experimental study of the partitioning of samarium between garnet and liquid at high pressures. In Papers Presented to the International Conference on Experimental Trace Elements Geochemistry, Sedona, Arizona. 

Harrison W. J. (1978). Rare earth element partitionings between garnets, pyroxenes and melts at low trace element concentration. Carnegie Inst. Wash. Yb., 77 682-689. 

The trace elements content and slight differences in major composition permit to split these three groups in five different sources two sources of pyrope garnets (with and without chromium) and two sources for almandine garnets (distinctive calcium, magnesium and yttrium contents). 

Hendricks, R. C. Dahl, P. S. (1987) Trace-element partitioning between coexisting metamorphic garnets and clinopyroxenes crystal field, compositional, and thermal controls. Geol. Soc. Amer., Ann. Meet., Abstr., 19, 700. 

Evidence of protracted growth history of skam garnet using SIMS oxygen isotope, trace element, and rare earth element data. Geol. Soc. Amer. Abstr. Prog. 1995. 

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. 

FREE enrichment in clinopyroxene is widely linked to metasomatism by either silicate melts or carbonatitic fluids, usually via cryptic (in the sense of no new phase being introduced) metasomatism, although there is a strong possibility that the diopside itself could have precipitated from the melt. This is strongly favored for much of the ubiquitously FREE-enriched diopside found in cratonic peridotites (Figure 17) which are not in trace-element equilibrium with their coexisting garnets and for which equilibrium melts for the diopside closely resemble kimberlite (Simon et al., 2003). 

In situ trace-element measurements of minerals from some of these peridotites provide a different perspective. The frequent presence of both fine-scale (100 p,m) zonation and nonequilibrium partitioning behavior for REE between many garnets and clinopyroxenes from Siberian peridotites (Shimizu etal, 1997 Shimizu, 1999)has two possible implications. One is the probable recent... 

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