- The Bartonian is, in the International Commission on Stratigraphy’s (ICS) geologic time scale, a stage or age in the middle of the Eocene Epoch or Series. The Bartonian Age spans the time between 41.2 and 37.71 Ma. It is preceded by the Lutetian and is followed by the Priabonian Age.
- Priabonian (Wikipedia)
The Priabonian is, in the ICS’s geologic timescale, the latest age or the upper stage of the Eocene Epoch or Series. It spans the time between 37.71 and 33.9 Ma. The Priabonian is preceded by the Bartonian and is followed by the Rupelian, the lowest stage of the Oligocene.
- Eocene (Wikipedia)
The Eocene (IPA: /ˈiːəsiːn, ˈiːoʊ-/ EE-ə-seen, EE-oh-) Epoch is a geological epoch that lasted from about 56 to 33.9 million years ago (Ma). It is the second epoch of the Paleogene Period in the modern Cenozoic Era. The name Eocene comes from the Ancient Greek ἠώς (ēṓs, “dawn”) and καινός (kainós, “new”) and refers to the “dawn” of modern (’new’) fauna that appeared during the epoch.
- Lutetian (Wikipedia)
The Lutetian is, in the geologic timescale, a stage or age in the Eocene. It spans the time between 47.8 and 41.2 Ma. The Lutetian is preceded by the Ypresian and is followed by the Bartonian. Together with the Bartonian it is sometimes referred to as the Middle Eocene Subepoch.