Elemental redistribution in Tieschitz and the origin of white matrix
Elemental redistribution in Tieschitz and the origin of white matrix
复制标题
Tieschitz 中的元素重新分布和白色矩阵的起源
DOI：
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发表时间：
1998
期刊：
影响因子：
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通讯作者：
J. Bridges
中科院分区：
文献类型：
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作者：
R. Hutchison;C. Alexander;J. Bridges
Abstract— Two types of mesostasis coexist within some porphyritic chondrules in Tieschitz. One type is smooth. The other, confined to chondrule margins, is blocky on a 5–10 μm scale. Mesostases in one porphyritic olivine‐pyroxene (POP) chondrule and one porphyritic olivine (PO) chondrule were analysed by scanning electron microscopy (SEM) and energy‐dispersive x‐ray spectrometry (EDS), as was white matrix nearby. Mesostases in the PO chondrule and in four others were analysed by ion probe. Pyroxene phenocrysts or dendrites extend across contacts between smooth and blocky mesostasis with no compositional change. Relative to smooth mesostasis, blocky mesostasis is enriched in Al, alkalis, Ba, F, and Cl but depleted in Si, Fe, and Ca. White matrix fills channels between the chondrules. It is physically and chemically similar to blocky mesostasis, but three ion probe analyses indicate that, unlike the mesostases, it is poor in Sc and has variable and fractionated rare earth elements (REEs).
