Rare Earth Elements and Oxygen Isotopes in Allende Chondrules as Evidence for Cai Mixing in Chondrule Precursors
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چکیده
Introduction: The relationship between calcium-alumnium-rich inclusions (CAIs) and chondrules remains poorly constrained. CAIs appear to be older than chondrules, as inferred from a higher initial 26 Al/ 27 Al in the former; a chronological interpretation of this difference leads to an age gap of ca.1-2Myr between the formation of CAIs and that of chondrules. However this chronological interpretation has been challenged by the suggestion that
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تاریخ انتشار 2003