Depositional environment changes during the early–late Serravallian boundary dated by the Central Paratethys bioevents

Abstract

The early–late Serravallian boundary (Badenian–Sarmatian) is a key interval for understanding Central Paratethys evolution. Environmental changes resulted in a great regional faunal turnover known as the Badenian-Sarmatian extinction event (BSEE). Here, we present a high-resolution sedimentological and biostratigraphical study from a rare site located on the Vienna and Danube basin junction (Slovakia). Four Middle Miocene depositional cycles/episodes ranked between 13.1 and 12.6 Ma are described in detail: (1) early Serravallian (13.1 Ma or older) shallow-marine episode; (2) early Serravallian (Badenian; Bulimina–Bolivina biozone; ~13.1 Ma or younger) outer shelf cycle; (3) late Serravallian (Sarmatian; large Elphidia biozone; ~12.6 Ma or younger) inner shelf cycle; (4) late Serravallian? A sedimentary episode represented by a scour filled with a reworked Serravallian (Upper Badenian and Sarmatian) material. The middle Miocene strata are overlaying and discordantly separated by Quaternary fluvial (floodplain) sediments (2.58 Ma or younger). These episodes reflect the early–late Serravallian turnover documented in the bioevents and in the sedimentological record.