SHOCKED SIXIANGKOU L6 CHONDRITE: FURTHER CONSTRAINTS ON CONDITIONS OF SHOCK METAMORPHISM. A. Zhang , W. Hsu, R. Wang, and M. Ding, 1 Laboratory for Astrochemistry and Planetary Sciences, Purple Mountain Observatory, Chinese Academy of Sciences, Nanjing 210008, China, [email protected], [email protected], [email protected], 2 State Key Laboratory for Mineral Deposits Research and Department of Ea...

Investigations of the Mantle Transition Zone (MTZ; 410-660 km deep) by deformation experiments and geophysical methods suggest that the MTZ has distinct rheological properties, but their exact cause is still unclear due to the lack of natural samples. Here we present the first direct evidence for crystal-plastic deformation by dislocation creep in the MTZ using a chromitite from the Luobusa per...

We report here detailed analytical scanning and transmission electron microscopic investigations on an olivine-dominated dust particle (RB-QD04-0042) from the surface of asteroid 25143 Itokawa. The dust particle was returned to Earth by the Hayabusa spacecraft and was made available in the context of the first announcement of opportunity for Hayabusa sample investigation. Multiple thin slices w...

Whiskers and needles of F-rich vesuvianite were found together with diopside in cavities of an altered magnesian skarn in the Tas–Khayakhtakh Mountains of Polar Yakutia, in Russia. The acicular crystals are strongly zoned and formed between two generations of diopside. The chemical composition of the vesuvianite whiskers is more homogeneous and resembles that of the outermost rim of the vesuvia...

Since antiquity, lapis lazuli has been highly valued across many cultures for its bright blue color. Due to the material’s significance, there has long been interest in understanding its color variations and determining its geographic origin, whether used as the processed pigment ultramarine in painted works of art (e.g. paintings and manuscripts) or the raw lapis lazuli stone in cultural herit...

with suggestions that fractionation of tholeiitic basalt in this pressure To model magmatic crystallization processes for mafic to intermediate range yields an alkalic basalt. Both trends may occur for natural compositions at high pressure, liquidus phase relations in the basalts depending on the Na2O content of the parental magma. forsterite–anorthite–diopside–silica (FADS) tetrahedron within ...