Middle-Upper Pleistocene reference section of the southern trans-Urals region

Data obtained during a long-term study of Pleistocene fluvial sediments in the Tobol River middle courses, the southern trans-Urals region, are discussed. The Zverinogolovskoe Formation defined in one of the fillstrath terraces of the Tobol River is divided into three lithological members each beginning with sands of channel facies and terminated by clays and slits of the oxbow or flood-plain facies. Lithological and mineralogical characterization of the members is accompanied by description of small mammal remains, molluscan and ostracode shells, and palynological assemblages. An upper part of the middle member corresponding to the normal-polarity interval is correlated with the paleomagnetic Gauss Chron. Based on the data complex, the lower and middle members are determined to be of the late middle Pleistocene (Piacenzian) age, and the upper member is attributed to the initial late Pleistocene (early Gelasian) based on microtheriofauna remains.