f Evaporites - the Key to Chronostratigraphic Subdivision of the Southern Rotliegend Basin

In the Southern Rotliegend Basin, evaporites represent widespread isochronous marker horizons which can be used for a chronostratigraphic subdivision of the up to 2000 m thick sedimentary column. The evaporites form part of sequences with evident cyclic depositional pattern. Until now, stratigraphic subdivisions of the Rotliegend have usually followed diachronous lithostratigraphical criteria. An isochronous system for the whole basin could not be developed so far, due to the paucity of fossiliferous material and the low reliability of radiometric data. A depositional model based on cyclic sedimentation does enable the isochronous Rotliegend lithostratigraphy. Only with such a model, individual depositional cycles can be traced basinwide, whereby basinal evaporites and fineclastics can be correlated with sandy deposits along the whole basin margin. Based on these correlations a new tectono-sedimentary model can be constructed.