The problem of updating the stratigraphic schemes of the ordovician-silurian of the Southern Urals

This article analyzes the current state of Ordovician and Silurian stratigraphic charts in the Southern Urals. The main problems are discussed and the tasks required to update regional stratigraphic charts are outlined. The changes required to existing stratigraphic charts affect the stratigraphic basis, which is created using new methodological principles related to global correlations of stage boundaries. Existing stratigraphic charts require numerous revisions and updating of the ages of stratigraphic units. The characterization of Paleozoic organic matter in the Suvanyak and Maksyutovo metamorphic complexes of the Uraltau region has led to a change in understanding of the region's structural-facies zones. A comprehensive approach to studying the sections, using the latest data on chemostratigraphy, zonal biostratigraphy, and micropaleontology, as well as a revision of previously made paleontological definitions, allows for the creation of an updated stratigraphic scheme for regional geological work and interregional and global correlations. The use of updated stratigraphic schemes also allows for refinement of paleogeodynamic models for the Ural folded system in the Paleozoic.