The Norwegian continental margin from the Northern North Sea to the Senja Fracture Zone

The Norwegian passive continental margin extends some 1100 km along-strike, from the UK border in the SW to the Senja Fracture Zone in the NE. The margin can be divided into three segments. The More segment in the south is a relatively simple, deep and broad Cretaceous basin close to the Norwegian mainland. The middle part is the Voring/Haltenbanken segment, a broad (400 km) and complex margin with a platform area (Trondelag Platform), terraces (Halten and Donna Terrace) and the deep, broad, Cretaceous/Early Tertiary Voring Basin on the seaward side. The northern part is the Lofoten/Vesteralen segment, where the peninsular Lofoten islands form a high, uplifted and narrow horst between the steep and structured Tertiary margin to the west, and the deep Vestfjord Basin of assumed Cretaceous age to the east. The development into passive continental margin segments occurred during the opening of the NE Atlantic in the earliest Eocene. The break-up was associated with massive volcanic activity and in particular the More and Voring segments form type examples of volcanic passive margins. The area had a very long history of extensional tectonics and rifting before the final successful opening. Extensional tectonics dominate, both as deep basement-involved faulting, and as more shallow listric faults locally detaching into Triassic evaporite layers; inversion and doming are also seen. In terms of extensional deformation the three segments developed differently, creating a variety of structural features. Across the broadest segment, the Voring Margin, an apparent lateral migration of rifting events exposes a development from at least Permian time.