GRV 051523: A new eucrite

• Main Authors: Tao, Liu, Yangting, Lin, Sen, Hu, Lu, Feng
• Format: Article in Journal/Newspaper
• Language: English
• Published: Polar Research Institute of China - PRIC 2009
• Subjects: Space; Grove Mountains; Advances in Polar Science; Polar Science
• Online Access: http://library.arcticportal.org/2384/; http://library.arcticportal.org/2384/1/A0090208.pdf

Grove Mountains (GRV) 051523 is a newly identified eucrite, consisting mainly of coarse-grained pyroxene (62.9 vol %) and plagioclase (34.2 vol %), with less abundant opaque minerals (2.7 vol %), minor silica and tiny FeO-rich olivine (Fa75). Coarse-grained pyroxenes show exsolution of augite lamellae in pigeonite or vice versa. Width of most exsolution lamellae in pyroxenes is 1-3 μm. Opaque minerals are mainly chromite, ilmenite and sulfides. The meteorite was heavily shocked, as indica ted by breccias and melt veins. Coarse-grained pyroxenes commonly contain abundant tiny or needle-like chromite inclusions with orientation, probably due to heavy shock events. Pyroxenes in various petrographic occurrences exhibit highly homogeneous compositions, indicating that GRV 051523 experienced intense thermal metamorphism in the parent asteroid 4 Vesta. GRV 051523 is classified as Type 5-6. This new eucrite will have additional constraints on chemical composition, magmatic differentiation, multi-stage shock and thermal history of Vesta.