Dear colleagues, We (Frances Deegan, Monika Rusiecka, and Hirochika Sumino) are organising session 04h at the upcoming Goldschmidt conference in Montréal entitled "Tracking volatiles and their stable isotope ratios from the mantle to the surface: understanding magmatic and tectonic systems". The solicited speakers include Sara Callegaro (Uni Bologna), who will give a keynote talk showcasing her work on using volatile contents of minerals to reconstruct volatile release from, among others, Deccan Traps, and Lauren Gorojovsky (Uni Oxford) who will give an invited talk on sulphur speciation and solubility under crustal conditions and Antonio Caracausi (INGV). Please consider submitting an abstract to our session. https://conf.goldschmidt.info/goldschmidt/2026/meetingapp.cgi/Session/9018 Full session description can be found below. See you in Montreal, Frances Deegan, Monika Rusiecka, and Hirochika Sumino Session Description: Volatile elements influence many processes throughout the upper mantle and lithosphere, including partial melting, magma genesis and evolution, eruption dynamics, redox changes, hydrothermal cycling, metal mobilisation, crustal recycling, and mineralogical transformations. Moreover, their escape through volcanoes and active seismic regions provides a unique window into the planet's dynamics. The compositions (including stable isotope ratios) of volatiles such as H, B, Li, S, halogens, and noble gases are powerful tracers, offering insights into processes within volcanic plumbing systems and active fault zones, and the broader chemical and isotopic evolution of Earth's interior. By combining volatile compositions with petrological, geochemical, and geophysical observations, this session explores how volatiles influence dynamic processes in the Earth's interior. The release of these volatiles is the driving force for volcanic eruptions, has fundamentally shaped the composition of Earth’s atmosphere, and plays a central role in the formation of magmatic ore deposits and earthquake nucleation. Constraining the source, abundance, and behaviour of volatiles in magmas thus has far-reaching and cross-disciplinary applications, including the use of volcanic gases as a tool for volcano monitoring and eruption forecasting, determining the effects of past and future eruptions on Earth’s atmosphere and climate, and understanding the formation of economically important mineral deposits. We invite submissions from a broad range of disciplines that aim to constrain the behaviour of volatiles from source to surface. We also welcome contributions that utilise volatiles and their stable isotope compositions to explore the role of melts, fluids, and volatiles in volcano-magmatic systems and active fault zones. Monika Rusiecka Postdoctoral Researcher Experimental Petrology Department of Earth Sciences University of Oxford [cid:8e2e86dd-aaa7-4538-a7ba-44ee60df65ea]