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Colpaert C., Pestchevitskaya E.B., Nikitenko B.L. (2017) Upper Jurassic foraminifera, dinoflagellates and terrestrial sporomorphsfrom the Gorodishche Section (Ul′yanovsk Region, East European Platform,Russia): Biostratigraphic, palaeoenvironmental and palaeobiogeographicalimplications // C. Colpaert et al. / Revue de micropaléontologie, 60. Pp. 549–572.

The Upper Kimmeridgian to Lower Volgian successions of the East European Platform are well represented in the clay formations of theGorodishche Section (Ul’yanovsk Region). It displays very rich foraminiferal and palynological assemblages. A review of foraminiferal andmicrophytoplankton biozonation is proposed in this study. Foraminiferal as well as marine and terrestrial palynomorph assemblages were alsoanalyzed to reconstruct environmental and climatic conditions during the transition from the Late Kimmeridgian to the Early Volgian. Thedepositional setting corresponds to the transition from the upper to the middle sublittoral zone mostly associated with oxic conditions. In addition,facies analysis allows the reconstruction of short term sea-level curve. Curves of the jaccard similarity Index have been constructed between theGorodishche Section and different regions of Eurasia in order to understand palaeobiogeographical changes. The results of the analyses indicatesignificant similarities of foraminiferal and dinocysts associations across East European Platform, Western Europe, and Siberia probably associatedto good connections between palaeobasins. The wide geographical range of foraminiferal and dinocyst zones indicates the possibility for longdistance correlations in the latest Kimmeridgian probably associated with palaeoenvironmental or/and palaeogeographical conditions favorablefor the marine biota exchange. Finally, palaeoclimatic reconstructions are derived from the analysis of spore–pollen associations. They indicate awarm arid to semi-arid climate with alternations of wet and dry seasons. The nature of the near-shore land vegetation was strongly influenced byhumidity fluctuations.

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