the bulk composition in the system that fixes the observed redox state? Besides, they would help in providing a more complete and formal redox description of geodynamic settings, in particular of how the redox state of magmas is a reflection of the source signature or the result of subsequent modifications due to magma evolution via partial melting, fractional crystallization, assimilation, or degassing (Carmichael, 1991; Burgisser and Scaillet, 2007; Gaillard et al., 2015; Moretti and Stefansson, 2020 and references therein) whose understanding would be beneficial at the scale of a single volcanic system to improve the forecasting of eruptions at both open‐conduit (generally basaltic) and closed‐conduit (generally andesitic) volcanoes via gas monitoring. Besides, this would better constrain the role of redox state on Earth’s evolution since its formation and accretion.
ACKNOWLEDGMENTS
We thank Alexander Pisch (SIMAP, CNRS, France) and Maria Rita Cicconi (FAU, Germany) for their valuable reviews. The precious support of AGU Books editorial staff is greatly acknowledged. This study contributes to the IdEx Université de Paris ANR‐18‐IDEX‐0001.
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