Paleogeography, paleobathymetry and relative sea-level changes in the Danube Basin and adjacent areas

The evolution of the Danube Basin is closely related to the extrusion of th e Western Carpathian and Transdanubian Central Range lithospheric fragments from the East Alpine collision zone and to the Middle Miocene back-are ext ension, associated with the formation of the Pannonian Basin System. Deposi ts of the Eggenburgian marine transgression, reaching the Danube Basin broa der area through the Alpine and Carpathian Foredeep, can be correlated with transgressive depositional system of the TB 2.1 cycle of Haq (1991). The t ransgressive sequence passes upwards into highstand, neritic to upper bathy al sedimentation. The Ottnangian marine and part of the anoxic and brackish sediments represent the falling stage deposition. The lowstand deposition which can be correlated with the TB 2.2 cycle of Haq (1991) appeared still in the Ottnangian, during the compressive tectonic event resulting in closu re of smaller basins. Later, during the Karpatian, sedimentation of transgr essive and highstand depositional systems took place, still on the present Danube Basin northern margin (Blatne Depression, Banovce Depression). The h igh energy environment of the basin attained deep neritic to upper bathyal depth. The angular discordance between the Karpatian and Badenian strata, v ery common absence of the Late Karpatian and Early Badenian deposits (prove d by micropaleontological data), as well as the presence of sediments of th is age in the Novohrad (Nograd) Basin and its equivalents in the Zeliezovce Depression (Danube Basin) suggest absence of the marine TB 2.3 cycle of Ha d (1991) in most of the territory. The whole area of the Danube Basin was f looded by the sea during the Middle to Late Badenian and Sarmatian. The sed imentation in the high energy environment of the neritic zone reflects two depositional cycles, which can be compared with the TB 2.4, TB 2.5 and TB 2 .6 cycles of Haq (1991). The Badenian cycle started with the Middle Badenia n rush transgression and highstand of the TB 2.4 cycle, followed by the Lat e Badenian higstand (SB type 2) and falling stage in the Bulimina-Bolivina Zone. The Sarmatian cycle started by a lowstand characterized by Ammonia ri ch assemblages on the Badenian-Sarmatian boundary and was followed by a tra nsgression and highstand which can be correlated with the TB 2.6 cycle of H aq (1991). The Late Miocene shallow water high energy brackish to delta-lak e sedimentation in the north and deep water high energy environment in the central and southern part represent equivalents of the TB 3 Haq (1991) cycl es.