| details |
Late Oligocene |
|
USSR(Siberia) |
Volkova,V.S. et al. Palynological evidence for the stratigraphic subdivision and correlation of Continental Paleogene and Neogene Depoits of Southern West Siberia and North Kazakhstan. |
1980 |
| details |
Early Oligocene |
Middle Oligocene |
USSR |
Aristova,K.E. Pollen and microplankton from the Eocene-Oligocene boundary deposits in the Southern Part of the USSR |
1973 |
| details |
Early Oligocene |
Middle Oligocene |
USSR(Trans-Urals) |
Li,P.F. et al. Continental deposits of the Paleogene and Neogene of the eastern Slopes of the Urals and Trans-Urals |
1967 |
| details |
Early Oligocene |
Middle Oligocene |
USSR(Urals) |
Li,P.F. et al. Continental deposits of the Paleogene and Neogene of the eastern Slopes of the Urals and Trans-Urals |
1967 |