A major drop in seawater 87Sr/86Sr during the Middle Ordovician (Darriwilian): Links to volcanism and climate?

  title={A major drop in seawater 87Sr/86Sr during the Middle Ordovician (Darriwilian): Links to volcanism and climate?},
  author={Seth A. Young and Matthew R. Saltzman and Kenneth A. Foland and Jeff S. Linder and Lee R. Kump},
A large drop in seawater 87 Sr/ 86 Sr during the Middle Ordovician was among the most rapid in the entire Phanerozoic. New 87 Sr/ 86 Sr measurements from Nevada indicate that the rapid shift began in the Pygodus serra conodont zone of the upper Darriwilian Stage. We use a numerical model to explore the hypothesis that volcanic weathering provided the flux of nonradiogenic Sr to the oceans. A close balance between volcanic outgassing and CO 2 consumption from weathering produced steady p CO 2… 

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