球粒是球粒陨石的主要组分，目前球粒分类体系主要有3种，即结构分类、FeO-SiO2分类和M-FeO-CaO分类。球粒结构分类过于依赖结构与形态，而与化学成分联系不紧密。 FeO-SiO2分类体系和M-FeO-CaO分类体系在传统的结构分类体系基础上加入了矿物化学分类参数，这有利于进一步研究太阳星云演化的物理化学过程。但与结构分类相比，很少利用FeO-SiO2和M-FeO-CaO分类体系对陨石球粒进行分类。本次所研究陨石为中国新发现的沙漠陨石富集区---新疆库木塔格沙漠004号陨石（L4，S4，W3），在对其中的球粒进行了详细普查和研究的基础上，分别利用3种分类体系对该陨石中的球粒进行分类，并进一步探讨了FeO-SiO2分类和M-FeO-CaO分类方法优缺点与应用范围。通过对比分析，提出了后两种分类方法的改进意见：针对FeO-SiO2分类体系，提出以硅酸盐中 FeO ＝7．5％（ wt％）为I型和Ⅱ型球粒分界线，SiO2＝47％及53％（ wt％）为A型、AB型和B型球粒分界线。 FeO-SiO2分类体系不仅能应用于斑状球粒，也适用非斑状球粒。对M-FeO-CaO分类体系依据辉石组分（ FeO及CaO，单位wt％）对A1型（FeO＜1，CaO＞1）、A2型（FeO≈1-3，CaO＜0．5）、A5型（FeO≈11-14，CaO≈0．3-0．9）和B型（FeO＞3，CaO＜0．5）球粒的类型区间进行了初步划分。%Chondrules are the main constituents of chondrites .There are 3 main kinds of classification schemes of chon-drules currently, i.e., texture, FeO-SiO2 and M-FeO-CaO.The texture classification depends on texture and mor-phology highly but chemical composition unclosely .The FeO-SiO2 and M-FeO-CaO classification schemes introduce mineral chemical criteria onto traditional texture taxonomic scheme and provide further insight into the physical -chemical process occurring in the solar nebula .But the practical applications are too few for the latter two schemes . The chondrules in Kumtag 004 (L4, S4, W3) from the new desert meteorites enrichment region-Kumtag desert of Xinjiang have been classified based on the three classification schemes after observing structure and analyzing com -position.Then we discuss the advantages and disadvantages of the FeO-SiO2 and M-FeO-CaO classification schemes and the application range .For the FeO-SiO2 taxonomic scheme that can be applied to porphyritic chondrules as well as non-porhyritic chondrules , we suggest that FeO =7.5% ( wt%) is the boundary between type I and Ⅱ chon-drules and so are 47%and 53%( SiO2 , wt%) for type A, AB and B chondrules .A approximate partition is pro-posed for the type A1(FeO<1,CaO>1), A2(FeO≈1-3,CaO<0.5), A5(FeO≈11-14,CaO≈0.3-0.9) and B(FeO>3,CaO<0.5) chondrules for the M-FeO-CaO classification scheme based on the pyroxene (FeO and CaO , wt%) .
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