CONCLUSIONS

1. IPLs from both archaea and bacteria were detected in organic-lean Paleogene sediments recovered during Leg 207. In contrast, we were not able to detect IPLs in organic-rich black shales, presumably due to higher detection limit caused by a polar organic matrix that was inseparable from polar fractions containing IPLs.
2. The IPL abundance is consistent with very low cell concentrations reported by Schippers and Neretin (this volume).