Reconstructing Slab and Mantle Fluxes during the Eocene-Oligocene Evolution of the Izu-Bonin Volcanic Arc (NW Pacific)
DESCRIPTION: The project aimed to complete the compositional characterization of the 42 million years rock record of the Izu Bonin volcanic arcs. This was done by using the record of ash beds in the marine sediment nearby, which allow for tracing the arc's evolution with high temporal resolution and precision. Major and minor trace elements and Sr-Nd-Pb-Hf isotope ratios were obtained from fresh volcanic particles.
OUTCOMES: Results show that since 42 million years the evolution of the Izu Bonin arc is in a steady state, and was influenced by the subduction of a crustal component with an Indian MORB-type signature hitherto not recognized from the Pacific plate subducting at the Izu Bonin trench.