The first finding of <i>Skeletognathus norrisi</i> in association with higher plant spores and brachiopods in the Givetian-Frasnian boundary deposits drilled by borehole No. 8 Tsarichanskaya (East Orenburg uplift, Russian Platform)

Research subject. Late Givetian-Early Frasnian brachiopods, conodonts and spores of higher plants from the Timan Horizon borehole No. 8 Tsarichankaya. Material methods. The biostratigraphical me thod was used to isolate fossils determine taxonomic compositions plant deposits drilled by Tsarichanskaya (interval 3637.00–3647.00 m), substantiate their age carry out a correlation. An improved technique I. Kh. Shumilov O. P. Telʼnova when proces sing spore samples. Results. uppermost Givetian zonal species Skeletognathus norrisi (Uyeno) identified. Brachiopods in association with are typical for Upper Subhorizon. results obtained clarify paleontological characteristics Givetian–Frasnian boundary interval on Russian platform. findings indicate wider range stratigraphical distribution (the latest Givetian–Early Frasnian), including Conclusions. marine terrestrial isolated same rock samples allowed authors provide complex characteristic Тiman Subhorizon, which is considered as being variant D2-D3 boundary. It significant interregional correlations different facies deposits.