Volatile element chemistry during metamorphism of ordinary chondritic material and some of its implications for the composition of asteroids
نویسندگان
چکیده
Please cite this article in press as: Schaefer, L., Fe implications for the composition of asteroids. Ic We used chemical equilibrium calculations to model thermal metamorphism of ordinary chondritic material as a function of temperature, pressure, and trace element abundance and use our results to discuss volatile mobilization during thermal metamorphism of ordinary chondrite parent bodies. We compiled trace element abundances in H-, L-, and LL-chondrites for the elements Ag, As, Au, Bi, Br, Cd, Cs, Cu, Ga, Ge, I, In, Pb, Rb, Sb, Se, Sn, Te, Tl, and Zn, and identified abundance trends as a function of petrographic type within each class. We calculated volatility sequences for the trace elements in ordinary chondritic material, which differ significantly from the solar nebula volatility sequence. Our results are consistent with open-system thermal metamorphism. Abundance patterns of Ag and Zn remain difficult to explain. 2009 Elsevier Inc. All rights reserved.
منابع مشابه
Volatile Element Chemistry during Metamorphism of Ordinary Chondritic Material and Some of its Implications for the Composition of Asteroids By
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