Late Cretaceous-Cenozoic intraplate contractional deformation at the Norwegian continental shelf: timing, magnitude and regional implications

Contractional structures (large anticlines and synclines, reverse faults an d inverted centres of deposition) of assumed Late Cretaceous-Cenozoic age a re common in Cretaceous-Tertiary basins of the northwestern European margin . The similarities in style, orientation and timing of these structures are striking. The present detailed analysis of one anticline (the Ormen Lange Dome) of the mid-Norwegian continental shelf indicates that the total contr action is moderate (less than 2-3%), and that the analysed anticline has be en growing almost continuously since its initiation in Eocene till Present. Inversion in the Barents Sea started already in the Late Cretaceous. This episode is suggested to be related to far-field effects of active plate-mar gin processes, and transfer of stresses across the plate as a consequence o f the sub Hercynian and Paleocene 'Laramide' event of the Alpine Orogeny. T he development of co-axial structures was facilitated by stress focusing al ong pre-existing, high-relief N-S- and NE-SW-trending fault complexes. Far- field plate tectonic stresses originating mainly from the Alpine Orogeny se em to have been the most important cause of contractional deformation on th e NW European shelf. In addition, ridge push from the North Atlantic spread ing may have contributed significantly, particularly during the Neogene. (C ) 1998 Elsevier Science B.V. All rights reserved.