Ostracods and Interregional Correlation between the Ordovician Sections of Northeast Russia (Eriekhe River Basin) and the Siberian Platform

In the Middle Ordovician sections of the Eriekhe River basin, which are of crucial importance to correlate the regional stratigraphic units of Northeast Russia and the General Stratigraphic Scale (by graptolites), we identified a diverse ostracod assemblage. The new data substantially supplement the Middle Ordovician paleontology of this region. The analysis of the stratigraphic distribution of these assemblages made it possible to verify the correlation of the Eriekhe Structural Facies Zone (SFZ) suites with regional stratigraphic units of the Northeast Russia and, based on homotypic ostracod assemblages, with the horizons of the Siberian Platform. The joint findings of ostracods and graptolites in the studied section allowed us to correlate the horizons of the Northeast Russia and the Siberian platform with the stages of the General Stratigraphic Scale.