南极格罗夫山陨石GRV020022的岩石矿物学特征  

Petrology and Mineralogy of the Meteorite GRV020022 Collected in Grove Mountains, Antarctica

作　　者：彭昊 刘燊[1] 李世杰[2] PENG Hao;LIU Shen;LI Shi-jie(Department of Geology,Northwest University,Xi’an 710069,China;Institute of Geochemistry,Chinese Academy of Sciences,Guiyang 550081,China)

机构地区：[1]西北大学地质学系,西安710069 [2]中国科学院地球化学研究所,贵阳550081

出　　处：《矿物岩石地球化学通报》2020年第2期216-222,共7页Bulletin of Mineralogy, Petrology and Geochemistry

基　　金：国家自然科学基金资助项目(41273080,41373067)。

摘　　要：GRV020022是第19次中国南极科学考察队在南极格罗夫山地区蓝冰上发现的一块陨石,为了解其矿物化学成分,对该陨石进行了扫描电镜观察和电子探针分析。结果显示,GRV020022陨石的主要组成矿物为橄榄石、低钙辉石、铁镍金属、陨硫铁、长石等,且矿物成分不均一,如橄榄石Fa 8.9-25.6(平均Fa18.3)和低钙辉石Fs 15.9-21.6(平均Fs 17.9),具球粒结构,基质有一定程度的重结晶,岩石类型属于4型。根据GRV020022陨石的橄榄石平均Fa值、低钙辉石平均Fs值、Fe-Ni合金含量及铁纹石中的Co含量(4.8 mg/g),将该陨石划归H群。另外陨石的冲击变质程度和风化等级分别为S3和W1。Meteorite GRV020022 was found in the blue ice field,Grove Mountains,Antarctica,during the 19 th Chinese Antarctic Research Expedition(CHINARE). In order to understand its mineral chemical composition, the sample was observed using SEM and analyzed using EPMA. The results show that the Meteorite GRV020022 is mainly composed of olivine, low-Ca pyroxene, metallic Fe-Ni, troilite, and feldspar. Its major minerals of olivine and low-Ca pyroxene have inhomogeneous compositions with Fa values varying from 8.9 to 25.6 and average of 18.3 for olivine and Fs values varying from 15.9 to 21.6 and average of 17.9 for low-Ca pyroxene. It has spherulitic texture with relatively sharp edges. Its matrix was moderately recrystallized. It belongs to Type 4 meteorite in lithology. Meanwhile, based on its mineral compositions, including mean Fa value of olivines, mean Fs value of low-Ca pyroxenes, abundance of metallic Fe-Ni alloy and the Co content of kamacite, the meteorite GRV020022 belongs to H type ordinary chondrite, with the impact metamorphic degree of S3 and weathering grade of W1.

关 键 词：南极陨石 格罗夫山 GRV020022 岩石矿物学 

分 类 号：P691[天文地球—地质学]