极地研究

极地研究 ›› 2010, Vol. 22 ›› Issue (3): 231-243.DOI: 10.3724/SP.J.1084.2010.00231

• 研究论文 • 上一篇    下一篇

南极格罗夫山H群普通球粒陨石冲击变质特征

王江1,缪秉魁2   

  1. 1. 桂林理工大学地球科学学院
    2. 桂林理工大学
  • 收稿日期:2010-05-10 修回日期:2010-06-11 出版日期:2010-09-30 发布日期:2010-09-30
  • 通讯作者: 王江
  • 基金资助:

    南极陨石冲击变质作用研究;我国南极不同化学群碳质球粒陨石的对比研究：早期太阳星云的演化特征及其不均一性

SHOCK METAMORPHISM OF H-CHONDRITES FROM THE GROVE MOUNTAINS, ANTARCTICA

Jiang Wang,   

  • Received:2010-05-10 Revised:2010-06-11 Online:2010-09-30 Published:2010-09-30
  • Contact: Jiang Wang

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被引次数

1

摘要：

本文研究了47块格罗夫山H群普通球粒陨石冲击变质效应。在光学显微镜下对陨石中硅酸盐矿物和不透明矿物的冲击变质效应，其中包括波状消光、破裂、马赛克消光、冲击熔融和金属硫化物枝状共晶进行了观察。利用扫描电镜对10块H群普通球粒陨石的不透明冲击熔脉进行观察与分析，在GRV022469冲击熔脉中发现了瓦茨利石。GRV022469成为我国第一块发现高压相矿物的南极H群普通球粒陨石。瓦茨利石的岩石矿物学特征表明它形成于固态相变机制。根据冲击变质效应，特别是冲击熔脉中矿物结构及成分，分析得出H群普通球粒陨石的冲击变质特征：H群普通球粒陨石冲击变质程度普遍偏低（低于S5），陨石中冲击熔脉宽度较窄，脉体中矿物组合为常压相矿物。

关键词: 冲击历史

Abstract:

Shock metamorphism of 47 H-Chondrites from Grove Mountains(GRV), Antarctica, were studied. Silicate and opaque minerals were observed under optical microscope for shock metamorphism features, such as undulatory extinction, planar fractures, mosaic extinction, shock-induced melting, and metal-sulfide dendritic eutectic. Shock-induced regions of 10 H-Chondrites were observed. Wadsleyite was found in GRV022469. Petrologic and mineralogical characteristics support that wadsleyite was formed by solid-state transformation. Based on shock effects, especially low-pressure phase mineral components and chemical characteristic, shock metamorphism stage of H-Chondrites is relatively low (lower than the S5). Shock-induced melt veins are thinner compared to those in L-Chondrites.

Key words: Shock History