Pages: 235 - 244
Abstract: Detailed analysis of microplankton occurrence (planktonic foraminifera, nannoplankton, dinocysts) in Neogene sediments situated at the north-western and south-eastern margins of Ukraine enabled us to distinguish 10 associations of oceanic plankton which specified the relative age of lithostratigraphic units of various regions and were used as correlation levels within the Central and Eastern Paratethys strata. Moreover, an attempt to correlate regional stages and the International Stratigraphic Chart (ISC) is performed. The Oligocene/Miocene boundary (of ISC) represented by the correlation level I was placed within the Central Paratethys regional stage Egerian and in the middle part of the Eastern Paratethys regional stage Caucasian s.l. The latter regional stage is subdivided by the correlation level into two substages: Lower Caucasian (Chattian of ISC) and Upper Caucasian (Aquitanian of ISC). The correlation level II was placed within the upper part of the Eggenburgian and lower part of the Batisifonian (Sakaraulian) regional stages and is correlated approximately with the middle part of the Burdigalian (of ISC). The base of the Middle Miocene is marked by level IV and was recognized only in deposits of the Eastern Paratethys belonging to the Tarkhanian regional stage. This level corresponds to the lowermost Badenian and Langhian (of ISC) stages. Correlation level V is traced in the Konkian sediments of the Eastern Paratethys and is compared with the Upper Badenian and Lower Serravalian (of ISC) stages. Level VI at the Middle/Upper Miocene boundary is situated in the middle part of the Bessarabian regional substage of the Eastern Paratethys and enables its correlation with the Serravallian/Tortonian boundary (of ISC). Level VII is recognized in the Baherovo Member (Meotian stage), while level VIII is fixed at the top of the Meotian regional stage in the Azov and Black Seas, Crimea and adjacent region named Northern Prichornomorye. Both these levels are also identified in the Berezhnytsya Formation of the Eastern Carpathian Foredeep. Correlation of these sediments is similar to the correlation of sediments of Lake Pannon (Pannonian regional stage), hence with the Tortonian stage (of ISC). Level IX was recognized in sediments of the Azov Member belonging to the Kimmerian regional stage of the Eastern Paratethys and represents the top of the Miocene strata. Level X occurs within the Taman Member of the Black Sea shelf and is correlated with the upper part of Kuyalnikian regional stage; corresponding to the Pliocene/Pleistocene boundary.
Keywords: Neogene, Paratethys, biostratigraphy, plankton correlation levels, foraminifers, nannoplankton, dinocystsDownload PDF document Show Text Version