This research was supported by Natural Environmental Research Council (NERC) Ph.D. Studentship NER/S/A/2001/063 to R.M. Coggon. Laboratory costs were covered by a NERC UK ODP Rapid Response Award to D.A.H. Teagle and R.M. Coggon. This research used samples and/or 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.