Izvestiya of Saratov University.
ISSN 1819-7663 (Print)
ISSN 2542-1921 (Online)


двустворчатые моллюски

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

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. Formation of the ?sponge?

Upper Cretaceous Deposits and Biostratigraphy of the «Novospasskoe» Section (South-West of the Ulyanovsk Region)

The section of campanian deposits of the south-west of the Ulyanovsk region characterized by a strata of “knotty” chalk is described. It was found relatively numerous faunal complex presented mostly by belemnites, bivalves and echinoids. The diversity of epibiontic organisms is described. The study of fauna has helped clarify stratigraphic position of the section within the scope of valid regional scheme.

New Paleontological and Stratigraphic Data on the Ryazanian Regiostage in the Oka River Sections (Central Russia)

Based on the study of cephalopods and bivalves, the paleontological characteristics of the Ryazanian (lowermost Lower Cretaceous) sections were supplemented in the stratoregion located in the Oka River Basin near Ryazan, Central Russia. The data obtained are important for the analysis of the stratigraphic position in subboreal sections of taxa known in the Arctic, and the subsequent qualitative development of the zonal level of scales for belemnites and buchias of the Jurassic-Cretaceous boundary interval of the Russian Plate.