New Data on Diatoms and Silicoflagellates of the Late Cretaceous of the Ust’-Manya Section, Severnaya Sos’va River, Subpolar Trans-Urals

Complexes of the Costopyxis antiqua diatom zone and the Cornua trifurcata silicoflagellate zone dated presumably to the middle Campanian have first been established in the diatomite layer at the re-examination of the outcrop of marine Upper Cretaceous deposits on the Severnaya Sos’va River in the area of the Ust’-Manya settlement. Associations with at least 40 diatom species and 10 silicoflagellate species are typical of an epicontinental basin with seasonal contrast. Analogues from sections of the eastern slope of the Urals, Northern territories of Canada, and the southeastern part of the East European Platform are known, which indicates stable interbasin connections of the Panboreal realm in the Campanian.