Nickolay M. Chumakov, 2011. "Glacial deposits of the Baykonur Formation, Kazakhstan and Kyrgyzstan", The Geological Record of Neoproterozoic Glaciations, Emmanuelle Arnaud, Galen P. Halverson, Graham Shields-Zhou
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The Baykonur Formation extends with some interruptions for over 1700 km along the eastern and northern margins of the Upper Precambrian Syrdarya and Tarim microcontinents. The Baykonur Formation constitutes the upper part of the Ulutau Group, which lies on an erosional surface of granosyenite with a U–Pb age of 720±20 Ma and is overlain by Lower Cambrian vanadium-bearing carbonaceous-siliceous shales. The Baykonur Formation is mostly composed of diamictite with erratic and striated stones, and includes thin-bedded shale beds with lonestones (dropstones) and a ‘cap dolomite’ unit at its top. The lithological composition of this formation implies a glaciomarine origin, while its stratigraphic position suggests a Late Vendian or an Early Cambrian age (the latest Ediacaran or Early Cambrian according to scale of the International Commission on Stratigraphy).