International Chronostratigraphic Chart (2017) Eocene Epoch Ypresian Age Paleocene Epoch Ipr ypresij Ypresiën Base of Eocene Ypris Ypres Ypres Ypres Yprésien ypresi Ypresiense ypres ypres younger bound -47.8 Ma Phanerozoic Eon Ypresien Lutetian Age Ipresiano Thanetian Age older bound -56 Ma Paleogene Period Ypresi Ypresian Ypersium 伊普雷斯期 イプレシアン期 Cenozoic Era Ипреѿ a1.1.1.3.2.4 Base of Lutetian ypresiano