THE LLANDOVERY-WENLOCK BOUNDARY IN THE RUSSIAN ARCTIC

Abstract

. The position of the Llandevery—Wenlock boundary in the Timan—northern Ural region and Severnaya Zemlya has been under discussion for a long time. Datings based on different groups of fauna seem to be inconsistent; conodonts indicate that in both regions this boundary lies considerably higher in the sequence than considered until now. The conodont datings agree well with correlations based on sea level fluctuations.