Interaction between mantle-derived magma and lower arc crust: quantitative reactive melt flow modeling using STyx

Riel, Nicolas; Bouilhol, Pierre; van Hunen, Jeroen; Cornet, Julien; Magni, Valentina; Grigorova, Vili; Velic, Marco

Abstract

The magmatic processes occurring in the lowermost arc crust play a major role in the evolution of mantle-wedge-derived melt. Geological evidence indicates that mantle-derived magmas and in-situ products of lower crust partial melting are reacting in a pervasive melt system and are eventually extracted towards higher levels of the crust. Resolving the relative contribution of mantle-derived magma and partial melting products of pre-existing crust is essential to: (1) quantify crustal growth rate; (2) better understand the compositional range of arc magmatic series; and (3) constrain the chemical differentiation of the lower crust. In this study, we present STyx, a new modelling tool, coupling melt and heat flow with petrology to explore the dynamics of storage, transfer and hybridization of melts in complex liquid/rock systems. We perform three models representing a magmatic event affecting an amphibolitic lower arc crust in order to quantify the relative contribution between partial melting of the pre-existing crust and fractional crystallization from mantle-derived hydrous-magma. Our models demonstrate that most of the differentiated arc crust is juvenile, deriving from the differentiation of mantle melts, and that pre-existing crust does not significantly contribute to the total thickness of magmatic products.

Citation

Riel, N., Bouilhol, P., van Hunen, J., Cornet, J., Magni, V., Grigorova, V., & Velic, M. (2018). Interaction between mantle-derived magma and lower arc crust: quantitative reactive melt flow modeling using STyx. Geological Society Special Publications, 478, 65-87. https://doi.org/10.1144/sp478.6

• Journal Article Type: Article
• Acceptance Date: Feb 20, 2018
• Online Publication Date: Apr 16, 2018
• Publication Date: Apr 16, 2018
• Deposit Date: Mar 25, 2018
• Publicly Available Date: Apr 16, 2019
• Journal: Geological Society Special Publications
• Print ISSN: 0305-8719
• Electronic ISSN: 2041-4927
• Publisher: The Geological Society
• Peer Reviewed: Peer Reviewed
• Volume: 478
• Pages: 65-87
• DOI: https://doi.org/10.1144/sp478.6
• Public URL: https://durham-repository.worktribe.com/output/1363537