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. Our heartfelt thanks go to the JOIDES Resolution crew, the SEDCO drilling crew, and the ODP technical crew for their enthusiastic cooperation and support. The success of this cruise is a tribute to Co-Chief Scientists Pinxian Wang and Warren Prell and Staff Scientist Peter Blum. Suggestions from Peter Blum and other reviewers improved the manuscript. This study was supported by the China Natural Sciences Foundation (grant no. 49732060).