A new generation of aeromagnetic surveys highlights the Caledonian basement grain and pre-Permian basin architecture of the southwestern Barents Sea. This configuration involved several Caledonian thrust sheets that reactivated and controlled the post-Caledonian rift development of the southwestern Barents Sea during Late Palaeozoic time. Contrary to previous geological models, we consider that the sub-Permian basins and underlying basement grain have a dominantly NNW–SSE orientation in most of the southwestern Barents Sea. Moreover, we do not see magnetic evidence that could support a major NE–SW or NNE–SSW regional axis that has commonly been proposed for the Late Palaeozoic rift system and inherited Caledonian structural grain in the Barents Sea.
An outline of the new magnetic profiles acquired during the BASAR project and an outline of the vintage magnetic profiles available before the BASAR project are available at www.geolsoc.org.uk/SUP18524.