Calcium isotope compositions as a means to trace carbonate recycling

Abstract

Marine carbonates, such as sedimentary carbonates and secondary carbonates formed during marine alteration processes, are returned to the mantle at subduction zones, and their fates regulate the global carbon cycle. Some carbonates are destroyed at the subduction zones, contributing to arc volcanism [1,2]. However, some subducted carbonatesmay be sampled by intraplate volcanism via mantle plumes or upwelling in big mantle wedges or rifts (e.g. [3,4]). Geochemists are exploring novel geochemical and isotopic tools that can be used to trace the recycled carbonate signatures in both mantle derived rocks (basalts) and mantle rocks (peridotites; see contributions in this issue).