This research used samples and data 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. Funding for this research was provided by the U.S. Science Support Program (USSSP), by the Ministry of Education, Science, Culture and Sports of Japan (MEXT) as the Grant-in-Aid for Scientific Research for the Ocean Drilling Program, by the Ocean Research Institute of the University of Tokyo, and by the Japan Agency for Marine-Earth Science and Technology (JAMSTEC). We acknowledge software grants from Landmark Graphics Corporation with which G.F. Moore and J.C. Moore processed and displayed seismic reflection data used on Legs 190 and 196, including Figures F4 and F5 herein. We thank Earl Davis for reviewing a draft of this paper and for providing Figure F8. ODP reviewers Don Fisher and Dave Scholl provided extremely useful comments that helped to clarify the text. We gratefully acknowledge the hard work by the publications staff at ODP-TAMU. Many thanks are also due to Adam Klaus, our Staff Scientist on both legs, for his help in making this program a success. This manuscript is SOEST contribution number 6520.