Stratigraphic synchronization of the uppermost Devonian and Lower Carboniferous of the Central and Southern North Sea area: palaeoenvironmental and source-rock implications

This contribution addresses the cross-border geology of the Upper Devonian and Lower Carboniferous of the UK, Dutch, Danish, German and Norwegian sectors of the Central and Southern North Sea. Using palynostratigraphic and log analysis, outcrop sections and well stratigraphic sections were tied to the geological timescale. Seven chronostratigraphic units were defined to better visualize lateral and temporal variations. Generalized stratigraphies and facies trends were summarized for 19 areas collectively covering the five national offshore sectors. The results show that two major regional unconformities affected deposition in the area; the Base Visean and the mid-Namurian unconformities. Particularly important phenomena are the development of extensive sandstones of the Fell Sandstone Formation by Arundian–Holkerian times and the development of cyclic delta-plain deposits, comprising both marine limestones and siltstones, as well as coals, by Asbian and Brigantian times. The Asbian marks an isolated phase of accumulation of lacustrine oil shales, in specific tectonic configurations.