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


аммониты

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?

About Possible Reflexion of Paleocological Conditions in Petromagnesism of Kallovian - Oxfordian Deposits of Dubki Section (Saratov)

As a result of the complex analysis of petromagnetic, micro- and macrofaunistic data of deposits on the Kallovian – Oxfordian boundary of Dubki section (Saratov), which is one of candidates for a role of a Global Boundary Stratotype Section and Point of Oxfordian boundary (GSSP), it is established significant correlation between magnetic susceptibility variations and changes of an abundance, a specific variety of ostracodes, foraminiferes and ammonites.

Faunal Assemblage of the Maastrichtian – Paleocene Intervals of Volsk Depression

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.

Representatives of the Subfamily Cheloniceratinae Spath, 1923 (Ammonoidea)from the Aptian of Mangyshlak, Western and Southern Turkmenistan. Paper 1. General Issues. The Genus Cheloniceras Hyatt, 1900

The article presents the study results of the ammonite subfamily Cheloniceratinae Spath, 1923 representatives (genera Cheloniceras Hyatt, 1900 and Epicheloniceras Casey, 1954) fromthe Lower and Middle Aptian of Mangyshlak, Western and Southern Turkmenistan. The diversity and stratigraphic distribution of species is assessed, intraspecific variability is identified and typified. Representatives of the genus Cheloniceras are described.