We thank Captain and Crew of the R/V Thomas G. Thompson (cruise TN229), the R/V Roger Revelle (cruise RR1002), and the SIO OBSIP facility for expert assistance at sea. The OBS instruments used in this field program were provided by the U.S. National Ocean Bottom Seismic Instrumentation Pool (http://www.obsip.org). MOANA seismic data are archived at the IRIS Data Management Center. The collection of ocean bottom seismic data was funded by the National Science Foundation under grants EAR-0409564, EAR-0409609, and EAR-0409835. New Zealand onshore seismic data made available by the GeoNet project, sponsored by EQC, GNS Science, and LINZ. J. Stachnik acknowledges support from the CIRES postdoctoral fellowship program.. F.-C. Lin was supported by NSF grant CyberSEES- 1442665 and the King Abdullah University of Science and Technology (KAUST) under award OCRF-2014-CRG3- 2300. We thank Martha Savage, Dan Zietlow, Justin Ball, Craig Jones, Bill Fry, and Peter Molnar for valuable comments and discussion, and John Collins for leading the MOANA OBS experiment. We thank two anonymous reviewers and Editor Mike Ritzwoller for their constructive comments.