Cretaceous tectonostratigraphy of the Faroe–Shetland region

Abstract

This study presents an appraisal of the Cretaceous tectonostratigraphical development of the Faroe–Shetland region. It combines details of the rock record with seismic stratigraphical information, and the resulting stratigraphic framework provides constraints on the timing and nature of sedimentary basin development in the Faroe–Shetland region, with implications for the Late Mesozoic development of the NE Atlantic Rift Zone. The division of the Cretaceous succession into two megasequences (K1 and K2) provides a first-order analysis of basin development. The components of the K1 megasequence represent the rift initiation and early syn-rift phases that span the late Berriasian–Turonian, whereas the K2 megasequence represents the rift climax incorporating basin enlargement and increased subsidence during the Coniacian–Maastrichtian. A higher resolution (second- to third-order) analysis of the component depositional packages highlights a sedimentary succession that is punctuated by episodes of uplift, erosion and contractional deformation. This pattern of coeval extension and compression is consistent with intra-plate strike-slip tectonic activity linked to the development of the NE Atlantic Rift Zone, and modulated by plate boundary processes, including Atlantic spreading and Alpine orogenic activity. There is no evidence for a substantive through-going marine connection in the Faroe–Shetland region until the Late Cretaceous.