Abstract

The Late Cretaceous-Tertiary structural evolution of the northeastern part of the Vøring Basin, mid-Norway, is highly complicated. Although tectonic activity occurred throughout Cretaceous time in much of the Vøring Basin, including the Gjallar Ridge and along the Fles Fault Zone, in the Vema Dome-Nyk High area evidence of such activity is not observed until the latest Maastrichtian time. In the Vema Dome-Nyk High area, several faults with both a NW-SE orientation and a NE-SW orientation have experienced lateral movements. The NE-SW orientation is the old Caledonian trend. The complex structural evolution of the Vema Dome-Nyk High area is probably related to the existence of continental weakness zones, which are the onshore extension of known oceanic fracture zones. The two lineaments that delineate these weakness zones, and that delineate the Vema Dome-Nyk High area, namely the Bivrost and Surt Lineaments, diverge slightly from one another toward the SE. This complex structural framework of NW-SE oriented lineaments and NE-SW oriented deep-seated basement structures of Caledonian compressional and/or Mesozoic rift origin, facilitated minor clockwise rotation of the area between the two lineaments during the extensional regime before the break-up of the North Atlantic, as well as during the compressional regime that has been proposed after the break-up.