Abstract
Decades of study have documented several orders of magnitude variation in the oxygen fugacity
Two different thermodynamic models were used to calculate
Observed variations in FMQ-normalized
Acknowledgments and Funding
We thank M.B. Baker, J.D. Blundy, E. Cottrell, J.M. Eiler, and B.J. Wood for helpful discussions and suggestions, and E. Cottrell, F. Davis, and B. Scaillet for helpful reviews. O.S. was supported at Caltech by a geology option postdoctoral fellowship and by a fellowship from Trinity College, Cambridge. P.D.A. and P.M.A. acknowledge support from NSF via award EAR-1550934. This manuscript was based on the first author’s 2017 Roebling Medal lecture.
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