Upper Campanian-lower Maastrichtian sections of northern Rostov oblast: Article 2. Depositional environments and paleogeography

• Published in: Stratigraphy and geological correlation 2014-09, Vol.22 (5), p.518-537
• Main Authors: Beniamovskii, V. N., Alekseev, A. S., Podgaetskii, A. V., Ovechkina, M. N., Vishnevskaya, V. S., Kopaevich, L. F., Pronin, V. G.
• Format: Article
• Language: English
• Subjects: Archaeology; Deep water; Earth and Environmental Science; Earth Sciences; Geological time; Geophysics/Geodesy; Historical Geology; Marine; Paleoecology; Paleozoic; Radiolaria; Sedimentation; Sedimentology; Stratigraphy; Structural Geology
• ISSN: 0869-5938; 1555-6263
• DOI: 10.1134/S0869593814050037

The study present the results of the integrated study on the Belgorod and Pavlovka formations (upper Campanian), Sukhodol Formation (Campanian-Maastrichtian), and Efremovo-Stepanovka Formation (Maastrichtian). Variations in lithological indicators and associated changes in the biotic assemblages were used to distinguish three stages in the basin evolution separated by hiatuses (Belgorod-Pavlovka, Sukhodol, and Efremovo-Stepanovka). This basin occupied the upland area in the north of the Paleozoic Donets Basin during late Campanian-early Maastrichtian times. Each stage was characterized by a specific depositional environment accompanied either by a decrease or by an increase in the terrigenous sediment supply from the Donets Basin and, possibly, Ukrainian Shield and sea-level and temperature fluctuations, as well as specific paleobiogeographic relations. During the Belgorod-Pavlovka stage, the basin was characterized by relatively deep-water environments, with warm waters and normal salinity, and predominantly carbonate sedimentation. The Sukhodol stage was marked by terrigenous sedimentation, a predominance of the agglutinated foraminiferal forms, and abundant radiolarians, which occurred during a marine regression and overall cooling. This stage corresponds to the global “Campanian-Maastrichtian boundary event.” The first half of the Efremovo-Stepanovka stage was marked by resumed carbonate sedimentation, warming, transgression, and deepening of the basin, which were replaced by a renewed regression at the end of this time interval.