Volatiles present in magma play a role of paramount importance on a number of physical and chemical parameters that govern magma behaviour. Understanding the ways volatiles are expelled out from cooling plutons to form ore deposits, or deconvoluting volcanic gas composition to detect an impeding volcanic eruption, are two examples illustrating the key role of magmatic volatiles on human-being related activities. However, despite decades of laboratory and field work, there are still numerous uncertainties as to volatile abundances and behaviour in magmatic systems, and the ways they are lost from magmas at depth or toward the atmosphere during their ascent through the crust.

This session thus calls for studies aimed at bringing experimental constraints on the role of volatiles in magmas, in addition to, or ideally in combination with, those providing constraints via analyses of natural systems (melt inclusions, volcanic gases etc...) using state-of-art analytical tools (SIMS, LA-ICPMS etc.). Modelling studies integrating both types of data are also welcome. Studies aimed at unravelling the connection between deep-seated processes, as recorded by either volcanic or plutonic systems, and surface observations will be given special attention.