极地研究

极地研究 ›› 2013, Vol. 25 ›› Issue (4): 352-361.DOI: 10.3724/SP.J.1084.2013.00352

• 研究论文 • 上一篇    下一篇

南极月球陨石EET96008矿物学和岩石学特征

夏志鹏1,2  缪秉魁1,2  陈宏毅1,2  姚杰1,2  谢兰芳1,2   

  1.  
    1桂林理工大学，广西矿冶与环境科学实验中心 广西 桂林 541004；
    2广西隐伏金属矿产勘查重点实验室 广西 桂林 541004
  • 收稿日期:2013-07-18 修回日期:2013-10-17 出版日期:2013-12-30 发布日期:2013-12-30
  • 通讯作者: 缪秉魁
  • 基金资助:

    月球火星陨石中后成合晶的研究;广西隐伏金属矿产勘查重点实验室主任基金项目;新疆沙漠陨石的收集与研究

THE PETROLOGY AND MINERALOGY OF LUNAR METEORITE EET 96008 FROM ANTARCTICA

Xia Zhipeng1,2，Miao Bingkui1,2，Chen Hongyi1,2，Yao Jie1,2，Xie Lanfang1,2   

  1.  
    1Guangxi Scientific Experiment Center for Mining, Metallurgy and Environment, Guilin University of Technology, Guilin 541004, China;
    2Guangxi Key Laboratory of Hidden Metallic Ore Deposits Exploration, Guilin 541004, China
  • Received:2013-07-18 Revised:2013-10-17 Online:2013-12-30 Published:2013-12-30

PDF (PC)

970

被引次数

3

摘要： EET 96008是一块发现于南极Elephant地区的玄武岩质角砾岩月球陨石。本文对该陨石的矿物岩石学特征进行了详细的观察和描述。EET 96008具有典型的碎屑结构，其角砾浑圆度低，角砾大小一般为0.1-2mm，它主要由角砾（50.2vol%）和基质（49.8vol%）组成，该陨石角砾类型多样：（1）晶屑：主要为辉石、橄榄石、长石以及石英；（2）岩屑：主要为变粒岩岩屑、基性岩岩屑、苏长岩质斜长岩岩屑；（3）玻屑：主要为斜长岩质。基质和角砾在颗粒上是连续过渡的，基质主要是由粒度小于0.1mm的矿物碎屑和玻屑组成。该陨石辉石类型多样，成分变化大Fs18.0-58.0Wo3.9-45.2En3.5-79.1，出溶现象普遍，出溶条纹达到1μm宽；橄榄石中Fa值主要分为两个区域，Fa50-70以及Fa80-95，铁含量较高，平均Fa71.8；长石成分以钙长石为主（An84.9-97.9）,部分斜长石已熔长石化。该陨石与QUE 94281同为月球玄武岩质角砾岩，在结构及矿物组成上具有类似性，但是在岩屑类型及橄榄石矿物成分上存在着明显不同，为非成对陨石，且源区可能不同。EET 96008具有三个典型的冲击暗化区域，有大量的玻璃质以及冲击熔融囊的产生，冲击程度达到S5以上。该陨石在冲击作用下，富铁辉石分解产生钙铁辉石-铁橄榄石-石英，该现象为了解月球表面冲击历史提供了重要的科学依据。

关键词: 月球陨石, EET96008, 月球角砾岩, 岩石学, 矿物学

Abstract: The EET 96008 is a lunar basaltic breccia collected from the Elephant Moraine region of Antarctica. The petrography and mineralogy of EET 96008 is described in detail. The meteorite has a typical breccias texture which consists of sub-angular clasts of clasts (50.2vol%) and matrix(49.8vol）, the clasts have the size of 0.1-2mm generally. The meteorite clast types are divided into three main categories: mineral clasts, rock clasts and glassy clasts: (1) Mineral clasts include pyroxene, olivine, feldspar and quartz. (2) And rock clasts are mainly granulite, basic rock and noritic anorthosite. (3) Glassy clasts are anorthositic. In grain size, the clasts and matrix vary gradually, the matrix consists of mineral clasts and glassy clasts which are only in smaller size than 0.1 mm. The meteorite has a variety of pyroxene. The pyroxene compositions cover almost over the entire pyroxene quadrilateral (Fs17.95-58; Wo3.95-45.17; En3.45-79.07). It also possesses extensive exsolution lamellae which are up to 1μm in width. Fe content in the olivine is relatively high, which can be mainly divided into two areas：Fa50-70 and Fa80-95, the average Fa is 71.8. The component of plagioclase in the EET 96008 is enriched in Ca. Some plagioclases have been converted into maskelynite. EET 96008 is the same lunar basaltic breccia as the QUE 94281, they share the similar texture and mineral assemblage. Their clear differences in clast type and mineral composition of olivine indicate that they are not paired and may came from the different source. EET 96008 has the three typical shock-induced darken areas, and a great deal of glassy clasts and shock pockets, suggesting that its shock stage should be above S5. The study on phenomenon that ferrosilite decomposes into hedenbergite - fayalite - quartz in the meteorite will provide the insight for the shock history of the lunar surface.

Key words: lunar meteorite, EET 96008, lunar breccia, petrography, mineralogy