Cretaceous tectonics off mid-Norway: implications for the Rockall and Faeroe-Shetland troughs

Abstract

Between 62° and 68°N on the Norwegian continental margin, the hypothesis of a Cretaceous or Permian ocean extending northwards from the Rockall Trough can be tested with data from commercial reflection seismic profiles. Two major Mesozoic basin systems occur. The Helgeland Basin is a late Triassic and early Jurassic depocentre with a thin Upper Jurassic and Cretaceous cover except in two late Cretaceous sub-basins. The Møre/lnner Vøring Basin system is a middle to late Cretaceous depocentre in which the pre-Cretaceous section is deeply buried and rarely seen on seismic profiles. The two basin systems are separated by a complex zone of faulted 'marginal highs' active in Jurassic times and reactivated during Cretaceous times. Pre-Cenomanian lavas or sills are interpreted within the Møre Basin and a pre-Cretaceous block-faulted sequence can be identified across the inner Vøring Basin except in a narrow axial zone. These features suggest the presence of an extremely narrow zone of oceanic crust of Cretaceous age. Fault patterns confirm a major tectonic episode of mid-Cretaceous age. The geology off mid-Norway supports a mid-Cretaceous age for sea-floor spreading in the Rockall Trough but suggests that the generated oceanic crust narrowed northwards and that plate motion was partially accommodated by dextral transcurrent faulting. Reconstruction of Jurassic tectonic trends in NW Europe must allow for subsequent Cretaceous distortion.

Continent–ocean-transitions: Review, and a new tectono-magmatic model of the Vøring Plateau, NE Atlantic

“…The present margin configuration results from three main rifing episodes: in Carboniferous to Permian, in late MidJurassic to Early Cretaceous and in Late Cretaceous to Early Eocene times (Bukovics et al, 1984;Gabrielsen et al, 1984;Price and Rattey, 1984;Surlyk et al, 1984;Brekke and Riis, 1987;Blystad et al, 1995;Doré and Lundin, 1996;Brekke, 2000). The last episode of rifting, leading to continental breakup at ca.…”

The onset of the North Atlantic Igneous Province in a rifting perspective

“…Jurassic E-W extension between Eurasia and North America-Greenland gave way to a dominantly NW-SE-directed extension in Early to Middle Cretaceous times (Doré et al 1999). The Middle Cretaceous extension resulted in northwards-narrowing sea-floor spreading from the Rockall Trough to the Vøring Basin off W Norway (Price & Rattey, 1984). Renewed NW-SE-directed extension occurred in the proto-NAIP area from the Late Cretaceous to the Early Palaeogene (Doré et al 1999).…”

Continent‐ocean transition on the Vøring Plateau, NE Atlantic, derived from densely sampled ocean bottom seismometer data

“…The Bivrost and Jan Mayen Lineaments continue into the oceanic crust as the Bivrost and Jan Mayen Fracture Zones (Transforms), respectively. [7] The tectonic activity that has given the present structural configuration of the margin may be traced back into Permo-Carboniferous time [Bukovics et al, 1984;Gabrielsen et al, 1984;Price and Rattey, 1984;Surlyk et al, 1984;Brekke and Riis, 1987;Blystad et al, 1995;Doré and Lundin, 1996;Brekke, 2000]. Three main rifting episodes are identified: in Carboniferous to Permian, in late Mid-Jurassic to Early Cretaceous and in Late Cretaceous to early Eocene times.…”