The Lower Badenian transgressive-regressive cycles - a case study from Oslavany (Carpathian Foredeep, Czech Republic)
Abstract
Two newly drilled boreholes (OSL-1 and OSL-2) at Oslavany (Carpathian Foredeep, Czech Republic, a holostratotype of the Moravian/Lower Badenian) provide data documenting the processes of the Lower Badenian marine transgression and regression along the passive margin of the peripheral foreland basin (south-eastern margin of the Bohemian Massif). Three facies associations show the evolution of the deposition and distinct basin margin paleogeography.
Deposits of marine transgression (transgressive lag) are followed by open-marine (outer to inner shelf) deposits interpreted as transgressive and highstand systems tract. They reflect a cratonward shift of the coastline.
The topmost foreshore and upper shoreface deposits (falling stage systems tract) recorded forced regression and basinward shift of the shoreline. The recorded transgressive-regressive cycle was induced by the coincidence of global TB 2.4. sea-level cycle and forebulge subsidence.
The identified higher-frequency cycles were interpreted as climatically controlled.