New insights into the Cretaceous-Cenozoic tectono-stratigraphic evolution of the southern Lofoten margin, offshore Norway

Abstract

Abstract The tectono-stratigraphic evolution of the southern Lofoten margin and its immediate transition towards the northern Voring margin has been studied in detail utilizing 2D multi-channel seismic reflection profiles, available wells, in addition to gravity and magnetic data. New and better refined structural elements have been mapped within the study area, including (informally named) the West Rost High Fault Complex, Rost Syncline, and Sandflesa High. Furthermore, four main rift phases have been recognised and refined. Late Jurassic-earliest Cretaceous rifting controlled the initial structuring of the main structural elements. Mid-Cretaceous rifting was responsible for initiation of faulting in the West Rost High Fault Complex, while a composite Late Cretaceous rift phase took place and led to westward propagation of fault activity. Paleocene rifting generated new faults and reactivated several earlier faults, prior to continental breakup and seafloor spreading initiation at the Paleocene-Eocene transition. The Bivrost Lineament, separating the southern Lofoten and northern Voring margins, has exhibited a distinct morphological expression during Cretaceous-Cenozoic and is recognised as a structural “corridor” which segments highs and basins/sub-basins. Furthermore, two dome-shaped features have been observed on the southern Lofoten margin and have probably experienced several phases of growth from Late Cretaceous to Miocene times. The domes are located in close proximity to the outer Voring margin and Bivrost Lineament that are believed to have facilitated the transfer of imposed compressional deformation on the NE Atlantic margins. Finally, a comparison of the study area to the conjugate Northeast Greenland margin provides valuable insights on the margin evolution in a regional and conjugate setting.