Geological framework of the Campine Basin. Geological setting, tectonics, sedimentary sequences

In preparation of the safety and feasibility case 1 for the geological disposal of high-level and long-lived radioactive waste in Belgium, the Boom Clay and its geological environment in the Campine area (NE Belgium) is studied. This report summarises the knowledge on the geological framework of the Campine. First, a brief description of the general geological setting of the Campine Basin is given. In order to understand the present-day geological framework of the Campine, we have to go back in geological history. We start with the description of plate tectonics, some 500 Ma ago, the collision and separation of continents, the creation of the London-Brabant Massif, and the tectonic subsidence of a large sedimentary basin in the north, i.e. the Campine Basin. Then, the thick sequences of sedimentary deposits which have been deposited within this large sedimentary basin during the Palaeozoic, Mesozoic and Cenozoic are described and interpreted in terms of tectonic evolution, sea-level changes and climate evolution. For the description of the sedimentary sequences, we refer to the geological time table and corresponding geological stratigraphical units, as indicated on the international stratigraphic chart. Finally, the dynamics of the Campine area are briefly discussed.