Earth science: Redox state of early magmas

  title={Earth science: Redox state of early magmas},
  author={Bruno Scaillet and Fabrice Gaillard},
A study of cerium in zircon minerals has allowed an assessment of the redox conditions that prevailed when Earth's earliest magmas formed. The results suggest that the mantle became oxidized sooner than had been thought. See Letter p.79 The composition of Earth's earliest atmosphere, which accumulated more than four billion years ago during the Hadean eon, may have been influenced by magmatic outgassing of volatiles from Earth's interior. This paper reports a redox-sensitive calibration to… 

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