Experimental investigations of trace element fractionation in iron meteorites. I - Early results

摘要: Experimental procedures for measuring trace element partitioning among metal and sulfide silicate phases are described, solid metal/liquid partition coefficients minor elements in the Fe-Ni system at 5 to 14% Ni reported. The bulk compositions desired homogenized superliquidus temperature 15-24 hours, held a solid/liquid two phase region about 24 quenched freeze equilibrium compositions. Run products analyzed by electron microprobe. With exception of Cr, all preliminary obtained same sense as values derived from iron meteorites. Cr metal/troilite systems suggest that IIIAB main group pallasites equilibrated with 9-22% troilite. A second method which makes it possible place upper lower limits on coefficient holding part sample subliquidus temperatures, yielded significantly different results metals tested (Au Pt) those first method, demonstrating importance close approach before using experimentally-determined test empirical differentiation models