echinoderms

Faunal Assemblage of the Maastrichtian – Paleocene Intervals of Volsk Depression

Authors: Pervushov E. M., Seltzer V. B., Kalyakin E. A., Musatov V. A., Ermokhina L. I., Ilinskiy E. I., Lopyrev V. A., Romanov N. S., Khudyakov D. V., Voronkov I. R.

Terminal layers of carbonate rocks of Maastrichtian and lower intervals of Paleocene aleurite-pelitic formations are accessible for investigation in Krasny Oktyabr and Bolshevik quarries (Volsk Depression). In the bottom of the Paleocene accumulation of skeletons of calcareous and siliceous sponges has been confirmed, mollusk and elasmobranch assemblage has been determined. Biozonal stratification of the location section and oryctocomplex analysis have contributed to specification of the processes in succession of benthic forms at the Upper Cretaceous – Paleogene boundary.

Integrated Bio and Magnetostratigraphic Study of the ≪Ozerki≫ Sections (Upper Cretaceous, Right Bank of the Volga in the Saratov Region). Paper 2. Oryctocoenosis Characteristics and Biostratigraphy

Authors: Pervushov E. M., Seltzer V. B., Kalyakin E. A., Fomin V. A., Ryabov I. P., Ilinskiy E. I., Gujikova A. A., Biryukov A. В., Surinskiy A. M.

In the ≪Ozerki≫ sections, in the terrigenous and carbonate rocks, a faunal complex has been determined – unusually diversified and relatively abundant for the right-bank part of the Saratov Region. Examination of the specified groups of fossil invertebrates has allowed to propose variants for biostratigraphic division and correlation of the sections under consideration. The carbonate rocks are supposed to belong to the Turonian-Coniacian and the underlying terrigenouscarbonate rocks are regarded as the Lower Turonian ones.