Petrography and mineral chemistry of four carbonaceous chondrites （ GRV 020017, GRV 020025, GRV 021579, GRV 022459 ） collected from the Grove Mountains （ GRV）, Antarctica, were reported here. All four chondrites a...Petrography and mineral chemistry of four carbonaceous chondrites （ GRV 020017, GRV 020025, GRV 021579, GRV 022459 ） collected from the Grove Mountains （ GRV）, Antarctica, were reported here. All four chondrites are unequilibrated, as indicated by well shaped chondrules and the chemical variations of olivine and low-Ca pyroxene. The modal abundance ratio of matrix/chondrule are 2 （ GRV 020017）, 2. 8 （ GRV 020025 ）, l. 2 （ GRV 021579 ）, 1 （ GRV 022459 ）. GRV 022459 has the largest chondrules （0.6--2.0 ram）. A total of 30 Ca-Al-rich inclu- sions were found in the four meteorites. Most inclusions were highly altered, with a- bundant phyllosilicates in the inclusions of GRV 020017 and GRV 020025. On the base of petrography and mineral chemistry, these chondrites are classified as CM2 （GRV 020017 and 020025）, CO3 （GRV 021579） and CV3 （GRV 022459）.展开更多
Petrography and mineral chemistry of ninety-eight ordinary chondrites from Grove Mountains （GRV）, Antarctica, were presented and their. Weathering effect, shock metamorphism and type distribution patterns were discu...Petrography and mineral chemistry of ninety-eight ordinary chondrites from Grove Mountains （GRV）, Antarctica, were presented and their. Weathering effect, shock metamorphism and type distribution patterns were discussed in this study. Among them, six are unequilibrated ordinary chondrites, including 3 H3 and 3 L3 ; and 92 meteorites are equilibrated ordinary chondrites, including 24 H-group （ 13 H4, 10 H5, 1 H6）, 64 L-group （2 L4, 44 L5, 18 L6） and 4 LL-group （3 LL4, 1 LL5）. Most GRV ehondrites （ 〉 90% ） displayed minor weathering effect （ W1 and W2）. About half of the meteorites experienced severe shock metamorphism. They commonly contain shock-induced melt veins and pockets. These heavily shocked meteorites provide us with natural samples for study of high-pressure polymorphs of minerals. In addition, the Grove Mountains collection seems to have more abundant unequilibrated and L group ordinary ehondrites compared to the US Antarctic meteorite collection which were mainly found along the Transantarctic Mountains.展开更多
基金supported by the Doctor's Foundation of Hunan University of Science and Technology(Grant No.E50806)
文摘Petrography and mineral chemistry of four carbonaceous chondrites （ GRV 020017, GRV 020025, GRV 021579, GRV 022459 ） collected from the Grove Mountains （ GRV）, Antarctica, were reported here. All four chondrites are unequilibrated, as indicated by well shaped chondrules and the chemical variations of olivine and low-Ca pyroxene. The modal abundance ratio of matrix/chondrule are 2 （ GRV 020017）, 2. 8 （ GRV 020025 ）, l. 2 （ GRV 021579 ）, 1 （ GRV 022459 ）. GRV 022459 has the largest chondrules （0.6--2.0 ram）. A total of 30 Ca-Al-rich inclu- sions were found in the four meteorites. Most inclusions were highly altered, with a- bundant phyllosilicates in the inclusions of GRV 020017 and GRV 020025. On the base of petrography and mineral chemistry, these chondrites are classified as CM2 （GRV 020017 and 020025）, CO3 （GRV 021579） and CV3 （GRV 022459）.
基金supported by the Doctor's Foundation of Hunan University of Science and Technology(Grant No.E50806)
文摘Petrography and mineral chemistry of ninety-eight ordinary chondrites from Grove Mountains （GRV）, Antarctica, were presented and their. Weathering effect, shock metamorphism and type distribution patterns were discussed in this study. Among them, six are unequilibrated ordinary chondrites, including 3 H3 and 3 L3 ; and 92 meteorites are equilibrated ordinary chondrites, including 24 H-group （ 13 H4, 10 H5, 1 H6）, 64 L-group （2 L4, 44 L5, 18 L6） and 4 LL-group （3 LL4, 1 LL5）. Most GRV ehondrites （ 〉 90% ） displayed minor weathering effect （ W1 and W2）. About half of the meteorites experienced severe shock metamorphism. They commonly contain shock-induced melt veins and pockets. These heavily shocked meteorites provide us with natural samples for study of high-pressure polymorphs of minerals. In addition, the Grove Mountains collection seems to have more abundant unequilibrated and L group ordinary ehondrites compared to the US Antarctic meteorite collection which were mainly found along the Transantarctic Mountains.
