Ordovician Stratigraphy, Facies, Deposition Environments, Faunas, Ichnofossils, and Paleogeography of Central Tyva

––A large regional-scale Ordovician continental basin has been revealed for the first time in Siberia. Sedimentary structures in the Ordovician rocks of Tyva represent deposition environments of rivers, oxbow lakes, dunes, river deltas, tidal, and coastal plains. Ichnofossils record a succession from freshwater (limnic-fluvial) to deltaic and tidal facies. Integrated studies of sedimentary rocks from Central Tyva show that they were deposited on a coastal plain within a large river delta. The Central Tyva Ordovician basin was similar to the coeval basins of the Gondwanian continents in the style of clastic and redbed deposition.