Classification of 24 New Ordinary Chondrites from the Grove Mountains, Antarctica  

作　　者：LURen MIAOBingkui WANGGuiqing DAIDeqiu LINYangting OUYANGZiyuan LIChunlai 

机构地区：[1]InstituteofGeochemistry,ChineseAcademyofSciences,Guiyang,Guizhou550002 [3]InstituteofGeologyandGeophysics,ChineseAcademyofSciences,Beijing100090 [4]GuanezhouInstituteofGeochemistry.ChineseAcademyofSciences,Guangzhou,Guangdong510640 [5]NationalAstronomicalObservatories,ChineseAcademyofSciences,Beijing100012

出　　处：《Acta Geologica Sinica(English Edition)》2004年第5期1052-1059,共8页地质学报（英文版）

摘　　要：Petrography and mineral chemistry of 24 ordinary chondrites from the Grove Mountains, Antarctica, have been studied in order to identify their chemical-petrographic types. These samples were selected from a total of 4448 Grove Mountains (GRV) meteorites collected during the 19th Chinese Antarctic Research Expedition so as to make an estimation of the large GRV meteorite collection. The chemical-petrographic types of these meteorites are presented below: 1 H3,2 H4, 4 H5, 2 H6, 1 L4, 7 L5, 5 L6, 1 LL4 and 1 LL6. The new data weaken the previous report that unequilibrated ordinary chondrites are unusually abundant in the Grove Mountains region. However, this work confirms significant differences in distribution patterns of chemical-petrographic types between the Grove Mountains and other regions in Antarctica. Many of these meteorites show significant terrestrial weathering, probably due to a high abundance ratio of meteorites found in moraines to those on blue ice. Nine meteorites experienced severe shock metamorphism, as evidenced by undulose extinction and intense fracturing of silicates and presence of shock-induced melt veins and pockets. These heavily shocked meteorites provided us with natural samples for the study of high-pressure polymorphs of minerals.Petrography and mineral chemistry of 24 ordinary chondrites from the Grove Mountains, Antarctica, have been studied in order to identify their chemical-petrographic types. These samples were selected from a total of 4448 Grove Mountains (GRV) meteorites collected during the 19th Chinese Antarctic Research Expedition so as to make an estimation of the large GRV meteorite collection. The chemical-petrographic types of these meteorites are presented below: 1 H3,2 H4, 4 H5, 2 H6, 1 L4, 7 L5, 5 L6, 1 LL4 and 1 LL6. The new data weaken the previous report that unequilibrated ordinary chondrites are unusually abundant in the Grove Mountains region. However, this work confirms significant differences in distribution patterns of chemical-petrographic types between the Grove Mountains and other regions in Antarctica. Many of these meteorites show significant terrestrial weathering, probably due to a high abundance ratio of meteorites found in moraines to those on blue ice. Nine meteorites experienced severe shock metamorphism, as evidenced by undulose extinction and intense fracturing of silicates and presence of shock-induced melt veins and pockets. These heavily shocked meteorites provided us with natural samples for the study of high-pressure polymorphs of minerals.

关 键 词：ANTARCTICA METEORITE ordinary chondrite CLASSIFICATION shock metamorphism thermal metamorphism 

分 类 号：P185.83[天文地球—天文学] P941.61