The stratigraphy of the Oligocene-lower Miocene deposits of southern Ukraine

Abstract

Lithostratigraphic units (formation, strata, and beds) and regional stages of the Oligocene-lower Miocene succession ofsouthern Ukraine are described based on the results of comprehensive lithological and paleontological data analysis. The historicalperspective on the stratigraphical investigations of the Maikop Group in the Crimean and Kerch Peninsulas and their equivalents inthe broader Peri-Black Sea Region were also integrated in this overview. Moreover, a correlation was established between the locallydefined regional stages and specific stratigraphic horizons of southern Ukraine, the global Oligocene and Miocene stages (defined by theInternational Stratigraphic Chart), and the stages of the Eastern Paratethys. The Planorbellian regional stage (early Rupelian) includesthe Borysfen, Planorbella, Indol, and Eastern-Kerch Formations and Diurmen Beds. The Molochnian regional stage (late Rupelian)includes the Molochna and Azamat Formations and the Kop-Takil Strata. The Kerleutian regional stage (latest Rupelian-Chattian)includes the Kerleut, Sirohozy, Askaniia, and Hornostaivka Formations and the Chorelek and Clay Stratum. The Bathysiphonianregional horizon (Aquitanian–Burdigalian) includes the Arabatska, Alahol, Chornobaivka, and Mayachka Formations and the KarhaBeds. This horizon is also considered as age-equivalent to the Caucasian, Sakaraulian, and Kotsakhurian regional stages of the lowerMiocene in the Eastern Paratethys. The Oligocene-early Miocene age of all these lithostratigraphic units belonging to the megaregionalMaikop Group is substantiated by paleontological data. This work represents the latest stratigraphic model of Oligocene-lower Miocenedeposits in southern Ukraine as a part of the Eastern Paratethys Basin.