摘要
本文研究了47块南极格罗夫山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。
Shock metamorphism of 47H-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 10H-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.
出处
《极地研究》
CAS
CSCD
北大核心
2010年第3期231-243,共13页
Chinese Journal of Polar Research
基金
中国科学院知识创新重要方向项目(kzcx2-yw-110-4)
国家自然科学基金项目(40673055)资助
