The cycling of elements between Earth’s deep and surface reservoirs has changed over Earths’ history. To gain a better understanding of elemental cycles, we employ various non-traditional stable isotope systems (Ca-Mo-Fe-Ti-Ba). The extent to which different subducted slab lithologies contribute to the isotope signatures in the mantle and magmas returning material to the surface is poorly constrained, as well as how compositions change by processes (such as dehydration, partial melting, fractional crystallisation) during subduction and magmatic ascent to the surface. Depending on the process we like to reconstruct we use the concentration and isotopic composition of redox-sensitive and/or fluid mobile and fluid immobile elements to further constrain the influence of redox conditions and element mass transfer during water-rock and mineral-melt interactions.
