THE INVESTIGATION OF ISOLATED OLIVINE INC LUSIONS AND MINERAL FRACTIONS OF THE KAINSAZ CO CARBONACEOUS CHONDRITE

Within the nonequilibrium carbonaceous chondrite Kainsaz CO olivine in clusions differing in their morphology and mineral composition were id entified. The detailed investigation of average elemental composition of such inclusions (with and without Fe-Ni phase) showed some substant ial differences, The inclusions of the first type are enriched in high temperature lithophile elements and depleted in Na and siderophiles. In relation to Ni the increase of Ir > Au > Co is observed, The olivin e inclusions without Fe-Ni phase are reported to be depleted in all de termined elements besides Sc [(1.3-1.9) CI] and Cr (1.2 CI), The conte nt of moderately volatile elements (Na, Co, Eu, Au) was found to incre ase along with grain size increase whereas the high temperature Sc, Sm and Ir decrease. These peculiarities could be interpreted in terms of a model of olivine inclusion and large chondrules formation. The mode l involves the agglomeration of small particles and the capture of fin ely dispersed low temperature matter. It is concluded that the isolate d olivine inclusions and chondrules of Kainsaz CO meteorite both were formed in remelting with the different condensation temperature of dus t components, Chemical composition of inclusions was characterised wit h the increase of low temperature fraction in the following succession : olivine inclusions with Fe-Ni phase < lithic and droplet like microp orphyric chondrules < olivine inclusions without Fe-Ni phase, The oliv ine and pyroxene fractions of the matrix are considered as individual mineral assemblages but not the fragments of chondrules.