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Abstract
This paper summarizes modern paleontological, bio-, and lithostratigraphic data from South Siberia on Ordovician sedimentary and volcanogenic-sedimentary formations of various origins: oceanic, marine, and continental. A study of the structure of Ordovician basins and their pelagic biotas within the folded framing of the Siberian Platform, known as the Altai-Sayan Folded Belt, has revealed considerably more complex spatial interrelations than a simple grouping adjacent to tectonic boundaries. Their current geographic arrangement, a jigsaw puzzle of contacting tectonic blocks within the Altai-Sayan Folded Belt, was formed in post-Ordovician time through multi-stage geodynamic events (contacts), including large-scale horizontal displacements.State-of-the-art research of the Altai, Salair, Kuznetsk Alatau, and Tyva Ordovician graptolite communities in the Altai-Sayan Folded Belt has been conducted. It provides conceptually new information on the paleozoogeographic specification of its individual geological regions and their parts (blocks), their proximity or remoteness from one another in the Ordovician, and sedimentation specificity.Possible migratory connections of graptolite communities in South Siberian marine basins are examined for individual Ordovician stages. Suggestions are made regarding the classification of the Altai, Salair, and Tyva Ordovician basins into well-known, distinct, and independent paleozoochories: Baltica, Laurentia, Peri-Gondwana, Gondwana, North China, South China, and Australasia. However, such suggestions are still more of a productive guide to the supposed assignment than definitive and well-reasoned proof.
