A critical analysis of the structure and tectonic significance of rift-oblique lineaments (‘transfer zones') in the Mesozoic–Cenozoic succession of the Faroe–Shetland Basin, NE Atlantic margin

Abstract

Abstract: NW–SE-trending rift-oblique lineaments (‘transfer zones') occur along the length of the NE Atlantic margin. Previous workers have suggested that these lineaments played an important role in providing conduits and/or barriers to sedimentation during the Cretaceous and Palaeocene; it has also been suggested that they were active as discrete, basin-wide strike-slip faults. This study uses a well-calibrated 3D seismic survey of regional extent to critically assess the structural and stratigraphic evidence for three rift-oblique lineaments in the UK sector of the Faroe–Shetland Basin (Victory, Clair and Judd Lineaments). Structures previously attributed to basin-wide strike-slip deformation can be more simply explained as igneous intrusions, hydrothermal vent complexes, gas chimneys and/or faults that transfer extensional strain between en echelon rift segments. There is little evidence to suggest that activity along discrete, basin-wide lineaments controlled Palaeocene sedimentation within the Faroe–Shetland Basin. Rather, sediment transport and deposition at this time are likely to have been controlled by along- and across-strike variations in the magnitude of thermal subsidence, which in turn reflect the 3D nature of the underlying Mesozoic rift architecture.