The foraminiferal zonal scale of the Devonian-Carboniferous boundary beds in Russia and Western Kazakhstan and its correlation with ammonoid and conodont scales

This paper reviews the foraminiferal biostratigraphy of the Devonian-Carboniferous (D-C) boundary beds in Russia and Western Kazakhstan. The regional records of the zonal successions of Russia are summarised from sections and boreholes of the Volga-Urals Subregion of the East European Platform (Syzran no. 401 Borehole, Melekesskaya no.1 Borehole); Timan-Pechora Province of the East European Platform (Kamenka Section); South Urals (Sikaza, Zigan, Ryauzyak and Dzerzhinka sections); Middle Urals (Pershino Section); and West Siberia, Vagai-Ishim Basin (Borehole no. 1 Kurgan-Uspenskaya), and the zonal successions of Western Kazakhstan are summarised from the Mugodzhary Mountains. Three foraminiferal biozones can be defined in the interval comprising the latest Devonian and earliest Carboniferous: Quasiendothyra kobeitusana Zone, the Tournayellina pseudobeata - remnant Quasiendothyra Zone, and the Earlandia minima Zone. The D-C boundary interval is situated within the Tournayellina pseudobeata-remnant Quasiendothyra Zone. A correlation with the ammonoid and conodont zonations is proposed, which is useful for correlating deep-water and shallow-water successions.

Automated summary

This paper reviews the foraminiferal biostratigraphy of the Devonian-Carboniferous (D-C) boundary beds in Russia and Western Kazakhstan, defining three foraminiferal biozones in the interval comprising the latest Devonian and earliest Carboniferous. A correlation with the ammonoid and conodont zonations is proposed, useful for correlating deep-water and shallow-water successions.