Comment on “Valence state of titanium in the Wark–Lovering rim of a Leoville CAI as a record of progressive oxidation in the early Solar Nebula― by K.A. Dyl, J.I. Simon and E.D. Young

نویسندگان

  • S. B. Simon
  • L. Grossman
چکیده

Dyl et al. (2011) state that their results confirm the conclusion of J. Simon et al. (2005) that the pyroxene in Wark–Lovering rims (Wark and Lovering, 1977) found on Ca-, Al-rich refractory inclusions has lower Ti/Ti ratios than the primary pyroxene in the interiors of inclusions. While true, the claim is misleading because J. Simon et al. (2005) concluded that there was no Ti in the rims, whereas Dyl et al. (2011) found Ti in 41 of 42 new rim analyses. In addition, J. Simon et al. (2005) concluded that rims formed under much more oxidizing conditions, log fO2 P IW-1, or P6–7 log units higher, than inclusion interiors. The conclusions of J. Simon et al. (2005) were disputed by S. Simon et al. (2007) and are not supported by the new data of Dyl et al. (2011). The present work is intended for clarification of this and other issues. 2012 Elsevier Ltd. All rights reserved.

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تاریخ انتشار 2012