Constraints on the Composition of Subducting Oceanic Crust in the Northwest Pacific Ocean Basin

Lead PI: Dr. Susanne M. Straub , Prof. Peter B. Kelemen , Steven L. Goldstein

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

July 2010 - June 2016
Pacific Ocean ; Lamont Doherty Earth Observatory (LDEO) ; Scripps Institute of Oceanography, CA
Project Type: Research

DESCRIPTION: The project tests the compositional link between volcanic arc magmas and the subducting slab. This will be done by compiling published trace elements and Pb, Sr, Nd and Hf isotope ratios in the northwest Pacific arcs and exploring their systematics relative to the trench input.

OUTCOMES: Our results conffirmed that the systematic of elements in arc magmas throught to be sensitive to the slab input are neither controlled by the composition of the crustal basement or of the mantle wedge. While this confirms the role of the slab input, the results also show that the composition of the subducting oceanic lithosphere may be insufficient to account for the compositional variation in arc magmas, which points to a role of crust eroded from the forearcs.


National Science Foundation (NSF)





Straub, S.M., Zellmer, G.F., 2012. Volcanic Arcs as Archives of Plate Tectonic Change. Gondwana Res, 21(2-3): 495-516, doi:10.1016/


volcanic arc subduction oceanic crust radiogenic isotopes


Earth fundamentals