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Three intervals of glaciomarine diamictites with extensive glendonites in middle to upper Permian sediments were found in the Kobyume River, southern Verkhoyanie, Russia. The successions are biostratigraphically constrained as middle to upper Permian. The middle Permian diamictite horizons extend over a large area with a lateral distance of >1000 km. The upper Permian diamictites developed only locally. The diamictites are interpreted as glaciomarine sediments containing ice-rafted debris. Two glacial episodes in Siberia temporally correspond to the P3 (middle Permian) and P4 (late Permian) glacial events of eastern Australia, strongly suggesting a global bipolar climate and well-developed climatic belts during the middle to late Permian.

In the present paper the 87 Sr/ 86 Sr values have been analysed for the Upper Kazanian regional stratotype section-Pechishchi and accompanied sections of Lower Kazanian and also Lower Permian. The section Pechishchi is unique section formed within the Kazanian palaeosea. It is characterized by three Noinsky's cycles of evaporitization of Kazanian palaeosea. The analysis of received data on 87 Sr/ 86 Sr shows that the highest ratios, characteristic of the Asselian, average at 0.70832. In the Artinskian, the 87 Sr/ 86 Sr ratios decrease to 0.70774. In the Kazanian, the strontium ratio is much lower: 0.70769 in the Early Kazanian and 0.70740 in the Late Kazanian. The position of received local data on global evolution 87 Sr/ 86 Sr curve, in common, is satisfactory. The discrepancies between local and global data observed at some points can be explained by the following: local features of the Permian deposition in the eastern part of the Russian Plate (the evaporitic trend and considerable isolation from the ocean); and problems with the chronostratigraphic positioning of the 87 Sr/ 86 Sr Phanerozoic evolution curve and local 87 Sr/ 86 Sr curves within the Permian. Multiple determinations of strontium isotope ratios in the Permian carbonates and the isotope dating of key samples would allow the revision of the Permian stratigraphic record. Strontium isotope stratigraphy offers an up-to-date and technologically advanced approach to the stratification and correlation of Permian sedimentary sections on both regional and global scales.

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