The characterisation of mantle volatile is a long standing subject of our group, with many discoveries over the last 40 years, from the characterisation of mantle, nitrogen, hydrogen, chlorine and sulfur isotope compositions.
Our studies aims to better document volatile heterogeneity, degassing and in-gassing flux of volatiles in the mantle. We study glasses (mid-ocean ridge and ocean-islan basalts, diamonds mantle xenoliths) and some subduction-related (i.e. metamorphic) rocks and altered oceanic crust in relation with key proxies (for example H2O/Ce, C/Nb, Cu/Y-ratios)
Our results have far reaching implications such as providing new proxies to characterise the the amounts of oceanic crust and fluids assimilated during magma emplacements (Cl-isotopes), the origin and timing of volatile delivery to Earth (O-, H-, C-, N-, S-isotopes) or the role of core sequestration (S-isotopes).
New projects which to better address volatile heterogeneity and its relationship with mantle oxygen fugacity.