A zircon case for super-wet arc magmas.

ABSTRACT: Arc magmas have higher water contents (2-6 wt.% H₂O) than magmas generated in other tectonic environments, with a growing body of evidence suggesting that some deep arc magmas may be 'super-wet' (>6 wt.% H₂O). Here, we use thermodynamic modelling to show that the behaviour of zirconium during magmatic differentiation is strongly sensitive to melt water contents. We demonstrate that super-wet magmas crystallise zircon with low, homogeneous titanium concentrations (75^th percentile <10 ppm) due to a decrease in zircon saturation temperatures with increasing melt H₂O. We find that zircon titanium concentrations record a transition to super-wet magmatism in Central Chile immediately before the formation of the world's largest porphyry copper deposit c

SUBMITTER: Nathwani C 

PROVIDER: S-EPMC11487280 | biostudies-literature | 2024 Oct

REPOSITORIES: biostudies-literature