南极格罗夫山普通球粒陨石的矿物岩石学特征

本文研究了第19次中国南极科学考察队收集的97块普通球粒陨石样品的矿物岩石学特征,在此基础上划分了陨石的岩石学类型、化学群、冲击变质和风化类型。共发现5块非平衡型普通球粒陨石:GRV 020011(L3),GRV 020035(H3),GRV 020054(H3),GRV 020137(L3)和GRV020169(L3)。化学群分类的结果是H群陨石24块,L群70块,LL群3块。多数样品的冲击变质程度较低,但也有少量样品具有S5型的冲击变质特征。样品的风化程度普遍较低,仅GRV020055(H5),GRV022123(L5)和GRV022462(LL6)3块陨石达到了W3型。

PETROGRAPHY AND MINERALOGY OF THE GROVE MOUNTAINS ORDINARY CHONDRITES

Ninety-seven ordinary chondrites,recovered from the Grove Mountains in Antarctica by the 19th CHINARE,were studied here.Based on their petrographic and mineralogical characteristics,the meteorites were divided into specific petrologic and chemical classes,as well as into different shock metamorphism and weathering stages.Five unequilibrated ordinary chondrites were identified: GRV 020011(L3),GRV 020035(H3),GRV 020054(H3),GRV 020137(L3) and GRV 020169(L3). There are twenty-four,seventy and three chondrites belonging to chemical groups H,L,and LL,respectively.The shock metamorphism stages of most chondrites are relatively low,but a few of them do have some features of S5 stages.The weathering of these Antarctic chondrites is mostly very limited,and only GRV 020055(H5),GRV 022123(L5) and GRV 022462(LL6) can reach the stage of W3.