Samples and/or data for this research were provided by the Ocean Drilling Program (ODP). ODP is sponsored by the U.S. National Science Foundation (NSF) and participating countries under management of Joint Oceanographic Institutions (JOI), Inc. This work was supported by the U.S. NSF-ODP and JOI-U.S. Science Support Program (USSSP). We thank Jon Childs for contributing the F-2-87-AA seismic data.