On the conditions of magma mixing and its bearing on andesite production in the crust

Abstract : Mixing between magmas is thought to affect a variety of processes, from the growth of continental crust to the triggering of volcanic eruptions, but its thermophysical viability remains unclear. Here, by using high-pressure mixing experiments and thermal calculations, we show that hybridization during single-intrusive events requires injection of high proportions of the replenishing magma during short periods, producing magmas with 55–58 wt% SiO2 when the mafic end-member is basaltic. High strain rates and gas-rich conditions may produce more felsic hybrids. The incremental growth of crustal reservoirs limits the production of hybrids to the waning stage of pluton assembly and to small portions of it. Large-scale mixing appears to be more efficient at lower crustal conditions, but requires higher proportions of mafic melt, producing more mafic hybrids than in shallow reservoirs. Altogether, our results show that hybrid arc magmas correspond to periods of enhanced magma production at depth.
Document type :
Journal articles
Complete list of metadatas

Cited literature [69 references]  Display  Hide  Download

https://hal-insu.archives-ouvertes.fr/insu-01096232
Contributor : Nathalie Pothier <>
Submitted on : Tuesday, July 4, 2017 - 11:11:05 AM
Last modification on : Friday, May 10, 2019 - 1:54:16 PM
Long-term archiving on : Thursday, December 14, 2017 - 11:20:27 PM

Licence


Distributed under a Creative Commons Attribution - NonCommercial - NoDerivatives 4.0 International License

Identifiers

Collections

Citation

Mickaël Laumonier, Bruno Scaillet, Michel Pichavant, Rémi Champallier, Joan Andújar, et al.. On the conditions of magma mixing and its bearing on andesite production in the crust. Nature Communications, Nature Publishing Group, 2014, 5, 12 p. ⟨10.1038/ncomms6607⟩. ⟨insu-01096232⟩

Share

Metrics

Record views

380

Files downloads

346