We thank Captain Ribbens and the crew of the JOIDES Resolution for a successful cruise; Tom Lorenson and Tim Collett for collecting our gas samples; Keith Kvenvolden for allowing us to borrow his stainless steel containers; and Charlie Paull for encouragement to pursue this research. Tim Collett kindly provided us with a translation of the Russian work by Verkhovsky et al. Gert DeLange and an anonymous reviewer are acknowledged for constructive comments (especially in full awareness that our data is less than ideal). We thank Robert Owen for signing and submitting the proposal on behalf of G. Dickens to receive funding from JOI-USSAC for this pilot study. This work was partly supported by the Director, Office of Energy Research, Office of Basic Energy Sciences, Engineering, and Geosciences Division of the U.S. Department of Energy under contract DE-AC03-76SF00098.