Reconstructing Slab and Mantle Fluxes during the Eocene-Oligocene Evolution of the Izu-Bonin Volcanic Arc (NW Pacific)

Lead PI: Dr. Susanne M. Straub

Unit Affiliation: Geochemistry, Lamont-Doherty Earth Observatory (LDEO)

June 2005 - June 2008
Inactive
Pacific Ocean ; Lamont Doherty Earth Observatory (LDEO) ; Izu Bonin arc
Project Type: Research

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.

SPONSOR:

National Science Foundation (NSF)

FUNDED AMOUNT:

$219,383

RESEARCH TEAM:

Steven Goldstein, Cornelia Class

PUBLICATIONS:

Straub, S.M., Goldstein, S.L., Class, C., Schmidt, A., 2009. Indian-type mid-ocean ridge basalts in the northwest Pacific Ocean basin. Nature Geoscience, 2(4): 286-289, DOI: 10.1038/NGEO471. Straub, S.M., Goldstein, S.L., Class, C., Schmidt, A., Gomez-Tuena, A., 2010. Slab and mantle controls of the Sr-Nd-Pb-Hf isotope evolution of the post-42 Ma Izu Bonin Volcanic Arc. J Petrol, 51(5): 993-1026; doi:10.1093/petrology/egq009.

KEYWORDS

radiogenic isotopes arc-trench connection volcanic ash subduction recycling magma izu bonin arc arc evolution

THEMES

Earth fundamentals