Chondritic meteorite fragments associated with the Permian-Triassic boundary in Antarctica.

نویسندگان

  • Asish R Basu
  • Michail I Petaev
  • Robert J Poreda
  • Stein B Jacobsen
  • Luann Becker
چکیده

Multiple chondritic meteorite fragments have been found in two sedimentary rock samples from an end-Permian bed at Graphite Peak in Antarctica. The Ni/Fe, Co/Ni, and P/Fe ratios in metal grains; the Fe/Mg and Mn/Fe ratios in olivine and pyroxene; and the chemistry of Fe-, Ni-, P-, and S-bearing oxide in the meteorite fragments are typical of CM-type chondritic meteorites. In one sample, the meteoritic fragments are accompanied by more abundant discrete metal grains, which are also found in an end-Permian bed at Meishan, southern China. We discuss the implications of this finding for a suggested global impact event at the Permian-Triassic boundary.

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عنوان ژورنال:
  • Science

دوره 302 5649  شماره 

صفحات  -

تاریخ انتشار 2003