The modelled conductive temperature field of the NE German basin in comparison with temperature measurements

The intracontinental NE German Basin is located between the stable Precambrian Baltic Shield to the north and the Caledonian/Variscan-influenced areas to the south. It forms part of the southern Rotliegend Basin, a series of interconnected basins extending more than 1500 km from England to Poland. Faulting, beginning in the Upper Carboniferous led to the development of an asymmetric basin with a gently dipping northern margin and a steep southern one. The current database consists of geophysical well logs and selected core material from 15 wells with Rotliegend strata together with newly-obtained deep seismic data (DEKORP Basin'96) and standard industrial profiles. The network of available seismic profiles cover an area of about 120x80 km along the northern margin of the NE German Basin. The Upper Rotliegend basin infill, comprising predominantly continental sediments, is up to 1400 m thick and was deposited over a period of ca. 8 Ma. Depositional environments include playa lake and sabkha in the basin centre interdigitating with dune fields and alluvial fans at the margins. The sedimentary record shows a cyclicity generated by periodic transgressions and regressions of the pronounced perennial saline lake. A series of detailed paleogeographic maps were constructed, showing the distribution of the main depositional environments, for the Upper Rotliegend. Of particular interest is the recognition of NE-SW-oriented channels, which acted as sediment transport conduits from the north, especially in the lowermost Upper Rotliegend. Sequence-stratigraphic analysis of geophysical well logs and core material allowed the recognition of a series of distinct sequences within the Upper Rotliegend succession. Control on the occurence of individual sequence cycles was climatic, related to changing lake levels within the basin.