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Late Cretaceous Microfossils as indicators of warming episodes (Boreal and Peri-Tethyan Russia)тезисы доклада
- Авторы: Vishnevskaya V.S., Kopaevich L.F.
- Сборник: 3rd International Congress on Stratigraphy, 2-5 July 2019, Milano, Italy. Abstract Book. Società Geologica Italiana, Roma
- Тезисы
- Год издания: 2019
- Место издания: Roma
- Первая страница: 1
- Последняя страница: 422
- Аннотация: The Late Cretaceous main palaeogeographic features of the Eastern European Platform (EEP) and its framework, as well as Western Siberia are summarized on the base of micropalaeontological data. An integrated foraminiferal-radiolarian Zonation for the Late Albian-Maastrichtian is presented for all this area and serves as a basis for palaeogeographic reconstructions. The study is mainly focused on the several timeslices: Late Albian–Cenomanian, Turonian–Coniacian, Santonian–Campanian and Maastrichtian intervals.The Late Albian time was characterized by tectonic rebuilding all this area, when a meridional sea–straight through the EEP disappeared, and connections with western part of Peri-Tethyan seas, and Tethys Ocean opened. The presence Tethyan species inside micropalaeontological assemblages confirms more warm climate compared the Late Albian. The Turonian-Coniacian interval is characterized by appearance of the planktonic foraminifers typical for Crimea-Caucasus area in sections of southern part of EEP. Upper Cenomanian−Lower Turonian foraminiferal Zone Whiteinella archaeocretacea is recognized not only in Crimea-Caucasus area, but in EEP and in the Western Siberia Basin. The rapid increase in the number of keeled specimens of Dicarinella, Marginotruncana among foraminifers and Alievium among radiolarians can be explained by Tethys transgression and rise of water temperature. As the result, during the Middle Turonian–Santonian time mainly carbonate sedimentation prevailed. However the cold Boreal water influence can be recognized not only on the northern margin of the EEP, but so far as Northern Caucasus during certain time interval and especially intensive during Campanian.The Western Siberia Boreal basin also influenced on climatic fluctuations through the Palaeo-Ural territory and Turgai strait. The formation of the siliceous wedge, which is composed of diatom and radiolarian skeletons, continued to the Campanian and Maastrichtian. The finding of plankton foraminifers and calcareous nannoplankton in Maastrichtian of the Westerm Siberia point to green house episode. The plankton foraminifers and calcareous nannoplankton and dinocysts Pithonella globosa Futterer, occurring in the Middle Maastrichtian also allows indicate a relatively warm episode during the sedimentation of the opoka like clay in the Saratov Volga Basin of EEP. This impulse is fixed in isotope data (Iakovishina et al., 2017). This research was supported by the IGCP-609 Project and the RFBR: 18-05-00494, 18-05-00495, 18-05-00503. Guzhikov A.Y., Baraboshkin E.Y., Benyamovskiy V.N., Vishnevskaya V.S., Kopaevich, L.F., Pervushov E.M. & Guzhikova A.A., (2017) - New bio-and magnetostratigraphic data on Campanian‒Maastrichtian deposits of the classical Nizhnyaya Bannovka section (Volga river right bank, southern Saratov region). Stratigraphy and Geological Correlation, 25(1), 39-75. Iakovishina E., Mashkina Y.A., Blinov I.V. & Bordunov S.I. (2017) - Maastrichtian paleotemperature changes in the Southern Russia. Berichte der Geologischen Bundesanstalt, Band 120, Wien, 122 pp.
- Добавил в систему: Копаевич Людмила Федоровна