This research used samples 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 German Research Foundation (DFG) to HP. Thanks to Dr. Beate Spiering (Mineralogisch—Petrologisches Institut, Universität Bonn) for her support at the microprobe.