Strike‐Slip Tectonics in the SW Barents Sea During North Atlantic Rifting (Swaen Graben, Northern Norway)

This study uses high‐quality, three‐dimensional (3‐D) seismic data to investigate the occurrence of strike‐slip faults in the Swaen Graben, SW Barents Sea. The Swaen Graben is divided into two principal subbasins: SSB1 and SSB2. The along‐strike and along‐dip displacement variations and scale relationships are analyzed for 42 faults. The displacement profiles for these faults are complex in the Swaen Graben, showing clear evidence for polycyclic fault growth and marked synsedimentary activity. The observed variations in the displacement profiles indicate complex along‐strike segmentation, linkage, and mechanical interactions at distinct structural levels. Along‐dip displacement minima indicate fault reactivation by dip linkage. Importantly, geometric evidence for strike‐slip faulting in the Swaen Graben includes the presence of extensional horsetail splay faults, positive flower structures, and minor transfer faults. This study shows that the faults in the Swaen Graben developed under extensional regimes during Late Jurassic to Early Cretaceous rifting and were reactivated by regional stresses during the Late Cretaceous. The two principal strike‐slip faults in the Swaen Graben reveal sinistral movement and are linked at a shallow depth by minor transfer faults at a relay zone. Our work further demonstrates the occurrence of Late Mesozoic strike‐slip movements in the SW Barents Sea, which were induced by regional tectonics, halokinesis, and fault block rotation. Importantly, strike‐slip faulting in the region extends perhaps into the Cenozoic interacting with extension during the North Atlantic rifting. Plain Language Summary The evolution of many basins in the Southwestern Barents Sea remains poorly understood for two main reasons. First, the geology of the area is complicated by different episodes of extensional tectonic events, geography, and climatic conditions. A second reason is the general lack of good‐quality data to constrain the geology of the basins. The current understanding of several basins in the Barents Sea relies on interpretation from old geophysical data. In this work, we use both simple traditional methods of fault analysis and geometrical observations to interpret the types and growth of faults within an area that is dominated by extensional faulting, that is, the Swaen Graben. Our results show a large basin that is characterized by two depressions, which formed by regional stretching during the Late Jurassic to Early Cretaceous. Region