Authors: Djerić, N., Jach, R., Goričan, Š., Reháková, D., Uchman, A., Gawlick, H-J., Schlög, J. & Stojadinović, U.

Abstract
The Jurassic to Early Cretaceous depositional history of the Carpatho-Balkanides reflects the graben (Early Jurassic) to passive continental margin (Middle Jurassic to Late Cretaceous) evolution of the Alpine Atlantic. As there is still no consensus about the Jurassic–Cretaceous palaeogeographic position of the Carpatho-Balkanides on the northern edge of the Moesian unit (Europe or wider Adria) a detailed knowledge of the passive continental margin depositional history is crucial to solving such open questions. Whereas the Early Jurassic graben infilling (Gresten Facies in a wider sense) is palaeogeographically only diagnostic to decide if units derive from the western or eastern Alpine Atlantic, the Middle Jurassic to Upper Cretaceous sedimentary successions differ in their overall lithology, sedimentological evolution, microfacies and geochemical characteristics on both the northern and southern margins of this oceanic domain but have only been studied in an overall manner up to now. Modern biostratigraphic age dating, sedimentological or geochemical studies are missing. Jurassic–Lower Cretaceous deposits along the valley of the Danube River in Serbia have been studied. The new biostratigraphic and microfacies results from the Middle–Upper Jurassic sedimentary rocks of the three successions are complemented by the obtained geochemical data. Detailed biostratigraphic analyses of radiolarians, calpionellids, dinoflagellates, and ammonites shed light on the paleoenvironmental and paleogeographic changes of the open marine environments in the Serbian part of the Carpatho-Balkanides, during Middle Jurassic–Early Cretaceous times. These successions indicate a typical horst-and-graben topography, well known from other domains of the Alpine Atlantic, formed during the continental break-up around the Early/Middle Jurassic boundary. Sedimentary successions deposited in deeper basins or in a horst position can be distinguished. The topographic difference was apparently diminished by the Early Cretaceous, when Maiolica type limestone above radiolarites and above condensed Rosso-Ammonitico-type limestone became ubiquitous. This depositional history resembles sedimentary successions from the northern units of the Eastern Alps or Western Carpathians. The successions studied are also closely similar to those of the Southern Alps, but the underlying rocks are different. The pre-Toarcian deposits in the study area are quartz sandstones and conglomerates (Gresten facies), whereas the coeval deposits of the Southern Alps are platform to deeper-water carbonates.