Carboniferous Strata in Maloyaroslavets (Kaluga Region) and Its Biostratigraphy Based on Foraminifers and Conodonts

Abstract

The study of a core of borehole 8 drilled in the town of Maloyaroslavets to a depth of 94 m has made it possible to obtain the biostratigraphic characteristics of the Tarusian and Protvian regional substages of the Serpukhovian Stage and lower part of the Vereian Regional Substage of the Moscovian Stage based on foraminifers and conodonts. The Tarusian Regional Substage is attributed to the Neoarchaediscus postrugosus Zone. The Eostaffellina paraprotvae Zone has been established in the Protvian Regional Substage, and a deep-water conodont assemblage of the Gnathodus bollandensis Zone has been found in its upper part (6.8–12.0 m above the base). The generalization of all data on conodonts of the Protvian Regional Substage of the Moscow Syneclise has shown that it contains at least four transgressive–regressive cyclites. The type locality of the species Eostaffellina protvaeensis has been specified in the Tetyuevo section in the Rzhev Volga region. A rich assemblage of conodonts from the Vereian Alyutovo Formation of the Moscovian Stage belongs to the Declinognathodus donetzianus Zone.