A Regional Upper Cretaceous Magnetostratigraphic Section of Western Siberia

The results of magnetostratigraphic studies of the Upper Cretaceous of Western Siberia are presented. A regional Upper Cretaceous magnetostratigraphic section of this territory is developed by comparing and linking reference Upper Cretaceous sections for the south, the center, and the north of Western Siberia. The reliability of paleomagnetic data is determined by the possibility of identifying the primary component of natural remanent magnetization and by the structural similarity of the developed scale with the worldwide geomagnetic polarity time scale. Upper Cretaceous geomagnetic field in the period from the Upper Albian to the Lower Paleocene, lasting approximately 38 Ma, reconstructed from the vectors of natural remanent magnetization, underwent 5 reversals (at the level of magnetozone boundaries) and recorded 3 normal and 2 reversal polarity regimes. A regional Upper Cretaceous magnetostratigraphic section of Western Siberia includes five magnetozones, three of normal N1K1–2(al2–st), N2K2km2, N3K2mt2 and two of reversal (R1K2km1 and R2K2mt1) polarity, compared to the worldwide geomagnetic polarity time scale. The scientific significance of the work is the regional Upper Cretaceous magnetostratigraphic section of Western Siberia developed for the first time. In terms of application, this section will make it possible to perform local, regional, interregional and global correlation of sections and geological events, as well as their dating.