Conodonts of the Krevyakinian and Khamovnikian Substages of the Kasimovian Stage in the Type Region (Moscow Basin)

Abstract

The Kasimovian Stage is a stage in the Pennsylvanian Subsystem, originally recognized in Russia. Its type area, despite the stage name (which is after the town of Kasimov in the Ryazan Region), is in the vicinity of the Voskresensk Region in the lower reaches of the Moscow River for the Krevyakian and Khamovnikian regional substages and the former village of Dorogomilovo (Moscow Region) for the Dorogomilovian Regional Substage. The stratotypes of the subdivisions of the Krevyakinian and Khamovnikian regional substages were established in the Voskresensk Region and no longer exist. The conodont assemblages of the Krevyakian and Khamovnikian and the lower part of the Dorogomilovian were studied in the neostratotype of the Kasimovian Stage (Afanasievo Section) and the Perkhurovo Reference Borehole drilled near the town of Voskresensk.