| 1 | Ca-, Al-rich Inclusions in Three New Carbonaceous Chondrites from the Grove Mountains, Antarctica: New Evidence for a Similar Origin of the Objects in Various Groups of Chondrites显示文摘Three new carbonaceous chondrites (GRV 020025, 021579 and 022459) collected from the Grove Mountains(GRV), Antarctica, have been classified as the CM2, CO3 and CV3 chondrites, respectively. A total of 27 Ca- and Al-rich inclusions have been found in the three meteorites, which are the earliest assemblages formed in the solar nebula. Most of the inclusions are intensively altered, with abundant phyllosilicates in the inclusions from GRV 020025 and FeO enrichment of spinel in those from GRV 022459. Except for one spinel-spherule in each of GRV 020025 and 021579, all the inclusions can be classified as Type A-like or spinel-pyroxene-rich inclusions, and they probably represent the continuum of solar nebular condensation. In addition, most of the inclusions in these meteorites share much similarity in both petrography and mineral chemistry, suggesting a similar origin of Ca-Al-rich inclusions in various chondrites. | DAIDeqiu LINYangting MIAOBingkui SHENGWenjie WANGDaode | 2004 | Acta Geologica Sinica(English Edition)2004，78，5： | 19 |
| 2 | Classification of 24 New Ordinary Chondrites from the Grove Mountains, Antarctica显示文摘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. | LURen MIAOBingkui WANGGuiqing DAIDeqiu LINYangting OUYANGZiyuan LIChunlai | 2004 | Acta Geologica Sinica(English Edition)2004，78，5： | 12 |
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