Lower Cretaceous biostratigraphy of Northern Siberia: palynological units and their correlation significance

The Berriasian-Barremian biostratigraphy based on spores and pollen of terrestrial plants found in sections from northern Siberia shows a succession of eight units. The ages of the units are proved by calibration against the Boreal zonal standard and their stratigraphic position is controlled by faunal and dinocyst records. The sections of the study are depth-stacked over one another, with partial overlap, and include several isochronous levels marked by the same palynological features. The levels are defined by changes in the taxonomic composition of spore-pollen assemblages found in the sections and recognized using published evidence from northern Siberia. Most of the identified boundaries of the palynostratigraphic units provide a good potential for northern Siberian regional correlation.