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Stratigraphical characteristics and development of Vendian–Cambrian boundary beds on the East European Platform

Abstract The present paper serves as a review on the stratigraphy and lithological characteristics of the Cambrian–Vendian boundary beds in the northwestern part of the East European Platform. This transition interval is represented by clastic rocks accumulated in humid climatic conditions. According to the lithological and palaeontological data the corresponding (transition) interval comprises two regional series: the Valdai Regional Series and the Baltic one. They both are divided into two regional stages (from below to top): Redkino, Kotlin, Rovno and Lontova. The Redkino–Kotlin and Kotlin–Rovno boundaries are characterized by distinct contacts reflecting various changes in the sedimentary environment whereas the boundary between the Rovno and Lontova regional stages drawn on the basis of the palaeontological data only falls within the interval of continuous sedimentation. Proceeding from the study of the fossil distribution and their living conditions during late Vendian and early Cambrian on the East European Platform the lower boundary of the Cambrian is most likely situated at the base of the Baltic Series.