摘要
主要报导了南极格罗夫山新回收的6块非平衡型普通球粒陨石的岩石学和矿物化学特征。它们都保存了原始的矿物-岩石学特征,包括非常清晰的球粒结构、基质不透明、橄榄石和低钙辉石颗粒具有明显的成分环带、以及颗粒之间极不均匀的化学组成等。这6块陨石包括3块高铁群(H3)和3块低铁群(L3)群。根据非平衡型普通球粒陨石中橄榄石成分Fa变化的PMD(相对标准偏差)值与陨石热变质程度的相关性,进一步划分岩石类型亚类:GRV 020016为H3.7型、GRV 020162为H3.5型、GRV 020166为H3.4型、GRV 020106为L3.7型、GRV 020164为L3.7型、GRV 020165为L3.7型。全部6块陨石的冲击变质程度很低,为S1-S2;样品比较新鲜,风化作用划分为W1-W2。
The petrography and mineral chemistry of 6 unequilibrated ordinary chondrites collected from the Grove Mountains, Antarctica, were studied. All meteorites show highly primitive petrography and mineral chemistry, as indicated by very shape-outlined chondrules, almost opaque fine-grained matrix , zoned grains of olivine and low-Ca pyroxene, and wide compositional ranges among grains. According to their petrography and mineral chemistry data, these meteorites are classified as 3 H3 and 3 L3 chondrites. Based on the relationship between the Percent Mean Deviation (PMD) of Fa of olivine and subtype of unequilibrated ordinary chondrites, they are subdivided with GRV 020016 as H3.7, GRV 020162 as H3.5, GRV 020166 as H3.4, GRV 020106 as L3.7, GRV 020164 as L3.7, and GRV 020165 as L3.7. We found these chondrites all experienced low-degree weathering and week shock metamorphism.
出处
《矿物学报》
CAS
CSCD
北大核心
2009年第3期405-412,共8页
Acta Mineralogica Sinica
基金
高等学校国家特色专业建设点基金(TS11027)
科技部社会公益基金(2005DKA21406-1)
湖南科技大学博士基金(E50806)
关键词
非平衡型普通球粒陨石
矿物-岩石学特征
分类
南极
unequilibrated ordinary chondrite
petrography and mineral chemistry
classification
Antarctica