Biostratigraphy of the marine Paleogene in the West Siberian Plate

The regional stratigraphic scheme suggested for the marine Paleogene deposi ts in the West Siberian plate is based on investigation results of macro- a nd microfossils (foraminifers, dinoflagellates, radiolarians, diatomaceous algae, silicoflagellates, Elasmobranchii, ostracodes, pollen, and spores). In the West Siberian plate, like in many structural-facies zones of the Eas t European platform, there was a hiatus in sedimentation at the Cretaceous- Paleogene boundary. The Talitsa Horizon corresponds here to the Danian and Selandian presumably coupled with the initial Thanetian. The lower Lyulin-V or Subhorizon is dated bask to the late Paleocene; the middle Lyulin-Vor Su bhorizon is correlated with the Ypresian, and the upper one is attributed t o the interval spanning the second half of the Ypresian and Lutetian, The T avda Horizon of the Bartonian-Priabonian age presumably comprises as well t he terminal Lutetian, The Kurgan Beds is. str,) representing marine facies of the Atlym Horizon correspond in the type area (near the town of Kurkan) to the lower Oligocene. Boundaries of these lithostratigraphic units are di achronous, since the Paleoarctis in the north and the Tethys in the south w ere connected with the epicontinental West Siberian sea basin producing an irregular impact on sedimentation in the latter.