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A dinocyst zonation for the Danish Neogene succession in the eastern part of the North Sea Basin is presented. Nineteen dinocyst zones are described, most of which are new. The zonation is correlated with other biostratigraphic subdivisions of the Neogene succession in the Danish region based on foraminifera and molluscs, as well as litho- and sequence stratigraphy. Absolute ages for the new dinocyst zones are proposed based on correlation with international zonations and stratigraphic schemes.
Neogene foraminifera and nannoplankton biostratigraphy in the North Sea Basin is problematic due to periodically limited connection between the North Sea Basin and the North Atlantic Sea. Many of the stratigraphically most important foraminifera and nannoplankton taxa, e.g. those defining stratigraphic boundaries in type sections, have not been found within the North Sea Basin. The new dinocyst stratigraphy does not have this problem as stratigraphically significant dinocyst taxa occur in the North Sea deposits, even in marginal marine settings. Therefore, the new dinocyst zonation has proven to be a valuable tool for unravelling the Danish Neogene succession. Furthermore, the geological model for the Neogene in Denmark is at present being correlated with other Neogene successions, e.g. in Germany, the Netherlands and Poland in order to elucidate the Neogene geology of the North Sea Basin. These correlations are based on the new dinoflagellate stratigraphy.
The new stratigraphy also leads to an improved understanding of the subsidence and tilting of the North Sea Basin during the Neogene, and consequently a better understanding of petroleum systems in the hydrocarbon producing provinces in the North Sea area. It is also an important tool for solving problems such as the mechanisms behind, and the timing of the Neogene uplift of Norway. On a global scale it adds to a better understanding of the causality and effects of climatic variation during the Neogene and thus the effects of the global climatic variation we see today, e.g. shifting of coastlines due to sea-level change.
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